[Federal Register: January 13, 2003 (Volume 68, Number 8)]
[Proposed Rules]               
[Page 1659-1763]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr13ja03-31]                         
 


[[Page 1659]]


-----------------------------------------------------------------------


Part II










Environmental Protection Agency










-----------------------------------------------------------------------






40 CFR Part 63






National Emission Standards for Hazardous Air Pollutants for 
Industrial/Commercial/Institutional Boilers and Process Heaters; 
Proposed Rule




[[Page 1660]]




-----------------------------------------------------------------------


ENVIRONMENTAL PROTECTION AGENCY


40 CFR Part 63


[OAR-2002-0058; FRL-7418-9]
RIN 2060-AG69


 
National Emission Standards for Hazardous Air Pollutants for 
Industrial/Commercial/Institutional Boilers and Process Heaters


AGENCY: Environmental Protection Agency (EPA).


ACTION: Proposed rule.


-----------------------------------------------------------------------


SUMMARY: The EPA is proposing national emission standards for hazardous 
air pollutants (NESHAP) for industrial/ commercial/institutional 
boilers and process heaters. The EPA has identified industrial/
commercial/institutional boilers and process heaters as major sources 
of hazardous air pollutants (HAP) emissions. The proposed rule would 
implement section 112(d) of the Clean Air Act (CAA) by requiring all 
major sources to meet HAP emissions standards reflecting the 
application of the maximum achievable control technology (MACT). The 
proposed rule would reduce HAP emissions by 58,000 tons per year, 
hydrogen chloride--a substance that is not considered to be a 
carcinogen--accounts for 42,000 tons per year (72 percent) of total HAP 
emissions reductions. The proposed rule would protect air quality and 
promote the public health by reducing emissions of some of the HAP 
listed in section 112(b)(1) of the CAA.
    The HAP emitted by facilities in the boiler and process heater 
source category include arsenic, cadmium, chromium, hydrogen chloride 
(HCl), hydrogen fluoride, lead, manganese, mercury, and nickel. 
Exposure to these substances has been demonstrated to cause adverse 
health effects such as irritation to the lung, skin, and mucus 
membranes, effects on the central nervous system, kidney damage, and 
cancer. The adverse health effects associated with the exposure to 
these specific HAP are further described in this preamble. In general, 
these findings have only been shown with concentrations higher than 
those typically in the ambient air.


DATES: Comments. Submit comments on or before March 14, 2003.
    Public Hearing. If anyone contacts EPA requesting to speak at a 
public hearing by February 3, 2003, a public hearing will be held on 
February 12, 2003.


ADDRESSES: Comments. Comments may be submitted by mail (in duplicate, 
if possible) to EPA Docket Center (Air Docket), U.S. EPA West (MD-
6102T), Room B-108, 1200 Pennsylvania Avenue, NW, Washington, DC 20460, 
Attention Docket ID No. OAR-2002-0058. By hand delivery/courier, 
comments may be submitted (in duplicate, if possible) to EPA Docket 
Center, Room B-108, U.S. EPA West, 1301 Constitution Avenue, NW, 
Washington, DC 20460, Attention Docket ID No. OAR-2002-0058. Also, 
comments may be submitted electronically according to the detailed 
instructions as provided in the SUPPLEMENTARY INFORMATION section.
    Public Hearing. If a public hearing is held, it will be held at the 
new EPA facility complex in Research Triangle Park, North Carolina, or 
an alternate site nearby.
    Docket. Docket ID No. OAR-2002-0058 contains supporting information 
used in developing the proposed rule. The docket is located at the U.S. 
EPA, 1301 Constitution Avenue, NW, Washington, DC 20460 in room B108, 
and may be inspected from 8:30 a.m. to 4:30 p.m., Monday through 
Friday, excluding legal holidays.


FOR FURTHER INFORMATION CONTACT: Jim Eddinger, Combustion Group, 
Emission Standards Division (C439-01), U.S. EPA, Research Triangle 
Park, North Carolina 27711, telephone number (919) 541-5426, fax number 
(919) 541-5450, e-mail: eddinger.jim@epa.gov.


SUPPLEMENTARY INFORMATION: Regulated Entities. The promulgation of the 
proposed rule would affect the following North American Industrial 
Classification System (NAICS) and Standard Industrial Classification 
(SIC) codes.


----------------------------------------------------------------------------------------------------------------
                                                                                         Examples of potentially
               Category                            NAICS code                SIC code      regulated entities
----------------------------------------------------------------------------------------------------------------
Any industry using a boiler or         211...............................           13  Extractors of crude
 process heater as defined in the                                                        petroleum and natural
 proposed rule.                                                                          gas.
                                       321...............................           24  Manufacturers of lumber
                                                                                         and wood products.
                                       322...............................           26  Pulp and paper mills.
                                       325...............................           28  Chemical manufacturers.
                                       324...............................           29  Petroleum refineries,
                                                                                         and manufacturers of
                                                                                         coal products.
                                       316, 326, 339.....................           30  Manufacturers of rubber
                                                                                         and miscellaneous
                                                                                         plastic products.
                                       331...............................           33  Steel works, blast
                                                                                         furnaces.
                                       332...............................           34  Electroplating, plating,
                                                                                         polishing, anodizing,
                                                                                         and coloring.
                                       336...............................           37  Manufacturers of motor
                                                                                         vehicle parts and
                                                                                         accessories.
                                       221...............................           49  Electric, gas, and
                                                                                         sanitary services.
                                       622...............................           80  Health services.
                                       611...............................           82  Educational services.
----------------------------------------------------------------------------------------------------------------


    This table is not intended to be exhaustive, but rather provides a 
guide for readers regarding entities likely to be regulated by this 
action. This table lists examples of the types of entities EPA is now 
aware could potentially be regulated by this action. Other types of 
entities not listed could also be affected. To determine whether your 
facility, company, business, organization, etc., is regulated by this 
action, you should examine the applicability criteria in Sec.  63.7485 
of the proposed rule. If you have any questions regarding the 
applicability of this action to a particular entity, consult the person 
listed in the preceding FOR FURTHER INFORMATION CONTACT section.


How Can I Get Copies of This Document and Other Related Information?


    Docket. The EPA has established an official public docket for this 
action under Docket ID No. OAR-2002-0058. The official public docket 
consists of the documents specifically referenced in this action, any 
public comments


[[Page 1661]]


received, and other information related to this action. Although a part 
of the official docket, the public docket does not include Confidential 
Business Information (CBI) or other information whose disclosure is 
restricted by statute. The official public docket is the collection of 
materials that is available for public viewing at the Air and Radiation 
Docket in the EPA Docket Center, (EPA/DC) EPA West, Room B108, 1301 
Constitution Ave., NW., Washington, DC. The EPA Docket Center Public 
Reading Room is open from 8:30 a.m. to 4:30 p.m., Monday through 
Friday, excluding legal holidays. The telephone number for the Reading 
Room is (202) 566-1744, and the telephone number for the Air and 
Radiation Docket is (202) 566-1742. A reasonable fee may be charged for 
copying docket materials.
    Electronic Access. You may access this Federal Register document 
electronically through the EPA Internet under the ``Federal Register'' 
listings at http://www.epa.gov/fedrgstr/.
    An electronic version of the public docket is available through 
EPA's electronic public docket and comment system, EPA Dockets. You may 
use EPA Dockets at http://www.epa.gov/edocket/ to submit or view public 
comments, access the index listing of the contents of the official 
public docket, and to access those documents in the public docket that 
are available electronically. Once in the system, select ``search,'' 
then key in the appropriate docket identification number.
    Certain types of information will not be placed in the EPA Dockets. 
Information claimed as CBI and other information whose disclosure is 
restricted by statute, which is not included in the official public 
docket, will not be available for public viewing in EPA's electronic 
public docket. The EPA's policy is that copyrighted material will not 
be placed in EPA's electronic public docket but will be available only 
in printed paper form in the official public docket. To the extent 
feasible, publicly available docket materials will be made available in 
EPA's electronic public docket. When a document is selected from the 
index list in EPA Dockets, the system will identify whether the 
document is available for viewing in EPA's electronic public docket. 
Although not all docket materials may be available electronically, you 
may still access any of the publicly available docket materials through 
the docket facility identified above. The EPA intends to work towards 
providing electronic access to all of the publicly available docket 
materials through EPA's electronic public docket.
    For public commenters, it is important to note that EPA's policy is 
that public comments, whether submitted electronically or on paper, 
will be made available for public viewing in EPA's electronic public 
docket as EPA receives them and without change, unless the comment 
contains copyrighted material, CBI, or other information whose 
disclosure is restricted by statute. When EPA identifies a comment 
containing copyrighted material, EPA will provide a reference to that 
material in the version of the comment that is placed in EPA's 
electronic public docket. The entire printed comment, including the 
copyrighted material, will be available in the public docket.
    Public comments submitted on computer disks that are mailed or 
delivered to the docket will be transferred to EPA's electronic public 
docket. Public comments that are mailed or delivered to the Docket will 
be scanned and placed in EPA's electronic public docket. Where 
practical, physical objects will be photographed, and the photograph 
will be placed in EPA's electronic public docket along with a brief 
description written by the docket staff.
    For additional information about EPA's electronic public docket, 
visit EPA Dockets online or see 67 FR 38102, May 31, 2002.
    You may submit comments electronically, by mail, or through hand 
delivery/courier. To ensure proper receipt by EPA, identify the 
appropriate docket identification number in the subject line on the 
first page of your comment. Please ensure that your comments are 
submitted within the specified comment period. Comments received after 
the close of the comment period will be marked ``late.'' The EPA is not 
required to consider these late comments. However, late comments may be 
considered if time permits.
    Electronically. If you submit an electronic comment as prescribed 
below, EPA recommends that you include your name, mailing address, and 
an e-mail address or other contact information in the body of your 
comment. Also include this contact information on the outside of any 
disk or CD ROM you submit, and in any cover letter accompanying the 
disk or CD ROM. This ensures that you can be identified as the 
submitter of the comment and allows EPA to contact you in case EPA 
cannot read your comment due to technical difficulties or needs further 
information on the substance of your comment. The EPA's policy is that 
EPA will not edit your comment, and any identifying or contact 
information provided in the body of a comment will be included as part 
of the comment that is placed in the official public docket and made 
available in EPA's electronic public docket. If EPA cannot read your 
comment due to technical difficulties and cannot contact you for 
clarification, EPA may not be able to consider your comment.
    Your use of EPA's electronic public docket to submit comments to 
EPA electronically is EPA's preferred method for receiving comments. Go 
directly to EPA Dockets at http://www.epa.gov/edocket, and follow the 
online instructions for submitting comments. To access EPA's electronic 
public docket from the EPA Internet Home Page, select ``Information 
Sources,'' ``Dockets,'' and ``EPA Dockets.'' Once in the system, select 
``search,'' and then key in Docket ID No. OAR-2002-0058. The system is 
an anonymous access system, which means EPA will not know your 
identity, e-mail address, or other contact information unless you 
provide it in the body of your comment.
    Comments may be sent by electronic mail (e-mail) to a-and-r-
docket@epa.gov, Attention Docket ID No. OAR-2002-0058. In contrast to 
EPA's electronic public docket, EPA's e-mail system is not an anonymous 
access system. If you send an e-mail comment directly to the Docket 
without going through EPA's electronic public docket, EPA's e-mail 
system automatically captures your e-mail address. E-mail addresses 
that are automatically captured by EPA's e-mail system are included as 
part of the comment that is placed in the official public docket and 
made available in EPA's electronic public docket.
    You may submit comments on a disk or CD ROM that you mail to the 
mailing address identified below. These electronic submissions will be 
accepted in WordPerfect or ASCII file format. Avoid the use of special 
characters and any form of encryption.
    By Mail. Send your comments (in duplicate if possible) to: Air and 
Radiation Docket and Information Center, U.S. EPA, Mailcode: 6102T, 
1200 Pennsylvania Ave., NW., Washington, DC 20460, Attention Docket ID 
No. OAR-2002-0058. The EPA requests a separate copy also be sent to the 
contact person listed above (see FOR FURTHER INFORMATION CONTACT).
    By Hand Delivery or Courier. Deliver your comments to: EPA Docket 
Center, Room B108, 1301 Constitution Ave., NW., Washington, DC, 
Attention Docket ID No. OAR-2002-0058. Such deliveries are only 
accepted during the Docket's


[[Page 1662]]


normal hours of operation as identified above.
    Do not submit information that you consider to be CBI 
electronically through EPA's electronic public docket or by e-mail. 
Send or deliver information identified as CBI only to the following 
address: Mr. Jim Eddinger, c/o OAQPS Document Control Officer (Room 
C404-2), U.S. EPA, Research Triangle Park, 27711, Attention Docket ID 
No. OAR-2002-0058. You may claim information that you submit to EPA as 
CBI by marking any part or all of that information as CBI (if you 
submit CBI on disk or CD ROM, mark the outside of the disk or CD ROM as 
CBI and then identify electronically within the disk or CD ROM the 
specific information that is CBI). Information so marked will not be 
disclosed except in accordance with procedures set forth in 40 CFR part 
2.
    In addition to one complete version of the comment that includes 
any information claimed as CBI, a copy of the comment that does not 
contain the information claimed as CBI must be submitted for inclusion 
in the public docket and EPA's electronic public docket. If you submit 
the copy that does not contain CBI on disk or CD ROM, mark the outside 
of the disk or CD ROM clearly that it does not contain CBI. Information 
not marked as CBI will be included in the public docket and EPA's 
electronic public docket without prior notice. If you have any 
questions about CBI or the procedures for claiming CBI, please consult 
the person identified in the FOR FURTHER INFORMATION CONTACT section.
    You may find the following suggestions helpful for preparing your 
comments:
    1. Explain your views as clearly as possible.
    2. Describe any assumptions that you used.
    3. Provide any technical information and/or data you used that 
support your views.
    4. If you estimate potential burden or costs, explain how you 
arrived at your estimate.
    5. Provide specific examples to illustrate your concerns.
    6. Offer alternatives.
    7. Make sure to submit your comments by the comment period deadline 
identified.
    8. To ensure proper receipt by EPA, identify the appropriate docket 
identification number in the subject line on the first page of your 
response. It would also be helpful if you provided the name, date, and 
Federal Register citation related to your comments.
    Public Hearing. Persons interested in presenting oral testimony or 
inquiring as to whether a hearing is to be held should contact Ms. 
Kelly Hayes, Combustion Group, Emission Standards Division (C439-01), 
U.S. EPA, Research Triangle Park, North Carolina 27711, telephone (919) 
541-5578 at least 2 days in advance of the public hearing. Persons 
interested in attending the public hearing must also call Ms. Kelly 
Hayes to verify the time, date, and location of the hearing.
    The public hearing will provide interested parties the opportunity 
to present data, views, or arguments concerning the proposed rule. If a 
public hearing is requested and held, EPA will ask clarifying questions 
during the oral presentation but will not respond to the presentations 
or comments. Written statements and supporting information will be 
considered with equivalent weight as any oral statement and supporting 
information presented at a public hearing, if held.
    Outline. The information presented in this preamble is organized as 
follows:


I. Background Information
    A. What criteria are used in the development of NESHAP?
    B. What is the regulatory development background of the source 
categories in the proposed rule?
    C. What is the statutory authority for the proposed rule?
    D. What is the relationship between the proposed rule and other 
combustion rules?
    E. What are the health effects of pollutants emitted from 
industrial/commercial/institutional boilers and process heaters?
II. Summary of the Proposed Rule
    A. What source categories and subcategories are affected by the 
proposed rule?
    B. What pollutants are emitted?
    C. What is the affected source?
    D. Does the proposed rule apply to me?
    E. What emission limitations and work practice standards must I 
meet?
    F. What are the testing and initial compliance requirements?
    G. What are the continuous compliance requirements?
    H. What are the notification, recordkeeping and reporting 
requirements?
III. Rationale of the Proposed Rule
    A. How did EPA determine which pollution sources would be 
regulated under the proposed rule?
    B. How did EPA select the format for the proposed rule?
    C. How did EPA determine the proposed emission limitations for 
existing units?
    D. How did EPA determine the MACT floor for existing units?
    E. How did EPA consider beyond-the-floor for existing units?
    F. Should EPA consider different subcategories for solid fuel 
boilers and process heaters?
    G. How did EPA determine the proposed emission limitations for 
new units?
    H. How did EPA determine the MACT floor for new units?
    I. How did EPA consider beyond-the-floor for new units?
    J. How did EPA determine testing and monitoring requirements for 
the proposed rule?
    K. How did EPA determine compliance times for the proposed rule?
    L. How did EPA determine the required records and reports for 
the proposed rule?
    M. How does the proposed rule affect permits?
    N. What alternative provisions are being considered?
IV. Impacts of the Proposed Rule
    A. What are the air impacts?
    B. What are the water and solid waste impacts?
    C. What are the energy impacts?
    D. What are the control costs?
    E. Can we achieve the goals of the proposed rule in a less 
costly manner?
    F. What are the economic impacts?
    G. What are the social costs and benefits of the proposed rule?
V. Public Participation and Requests for Comment
VI. Administrative Requirements
    A. Executive Order 12866, Regulatory Planning and Review
    B. Executive Order 13132, Federalism
    C. Executive Order 13175, Consultation and Coordination with 
Indian Tribal Governments
    D. Executive Order 13045, Protection of Children from 
Environmental Health Risks and Safety Risks
    E. Unfunded Mandates Reform Act of 1995
    F. Regulatory Flexibility Act as Amended by the Small Business 
Regulatory Enforcement Fairness Act of 1996 (SBREFA), 5 U.S.C. 601 
et seq.
    G. Paperwork Reduction Act
    H. National Technology Transfer and Advancement Act
    I. Executive Order 13211, Actions Concerning Regulations That 
Significantly Affect Energy Supply, Distribution, or Use


I. Background Information


A. What Criteria Are Used in the Development of NESHAP?


    Section 112 of the CAA requires EPA to promulgate regulations for 
the control of HAP emissions from each source category listed under 
section 112(c) of the CAA. The statute requires the regulations to 
reflect the maximum degree of reductions in emissions of HAP that is 
achievable taking into consideration the cost of achieving emissions 
reductions, any nonair quality health and environmental impacts, and 
energy requirements. This level of control is commonly referred to as 
MACT. The MACT based regulation can be based on the emissions 
reductions achievable through application of measures, processes, 
methods, systems, or techniques


[[Page 1663]]


including, but not limited to: (1) Reducing the volume of, or 
eliminating emissions of, such pollutants through process changes, 
substitutions of materials, or other modifications; (2) enclosing 
systems or processes to eliminate emissions; (3) collecting, capturing, 
or treating such pollutants when released from a process, stack, 
storage or fugitive emission point; (4) design, equipment, work 
practices, or operational standards as provided in subsection 112(h) of 
the CAA; or (5) a combination of the above.
    For new sources, MACT based standards cannot be less stringent than 
the emission control achieved in practice by the best-controlled 
similar source. The MACT based standards for existing sources can be 
less stringent than standards for new sources, but they cannot be less 
stringent than the average emission limitation achieved by the best 
performing 12 percent of existing sources for categories and 
subcategories with 30 or more sources, or the best performing 5 sources 
for categories or subcategories with fewer than 30 sources.
    In essence, these MACT based standards would ensure that all major 
sources of toxic air emissions achieve the level of control already 
being achieved by the better-controlled and lower-emitting sources in 
each category. This approach provides assurance to citizens that each 
major source of toxic air pollution will be required to effectively 
control its emissions. A major source of HAP emissions is any 
stationary source or group of stationary sources located within a 
contiguous area and under common control that emits or has the 
potential to emit any single HAP at a rate of 10 tons or more per year 
or any combination of HAP at a rate of 25 tons or more a year. At the 
same time, this approach provides a level economic playing field, 
ensuring that facilities that employ cleaner processes and good 
emission controls are not disadvantaged relative to competitors with 
poorer controls.


B. What Is the Regulatory Development Background of the Source 
Categories in the Proposed Rule?


    In September 1996, EPA chartered the Industrial Combustion 
Coordinated Rulemaking (ICCR) advisory committee under the Federal 
Advisory Committee Act (FACA). The committee's objective was to develop 
recommendations for regulations for several combustion source 
categories under sections 112 and 129 of the CAA. The ICCR advisory 
committee, known as the Coordinating Committee, formed Source Work 
Groups for the various combustion types covered under the ICCR. One of 
the work groups was formed to research issues related to boilers; 
another was formed to research issues related to process heaters. The 
Boiler and Process Heater Work Groups submitted recommendations, 
information, and data analysis results to the Coordinating Committee, 
which in turn considered them and submitted recommendations and 
information to EPA. The Committee's recommendations were considered by 
EPA in developing the proposed rule for boilers and process heaters. 
The Committee's 2-year charter expired in September 1998.
    Following the expiration of the ICCR FACA charter, EPA decided to 
combine boilers with units in the process heater source category 
covering indirect-fired units, and to regulate both under the proposed 
NESHAP. This was done because indirect-fired process heaters and 
boilers are similar devices, burn similar fuel, have similar emission 
characteristics, and emissions from each can be controlled using 
similar control devices or techniques.


C. What Is the Statutory Authority for the Proposed Rule?


    Section 112 of the CAA requires that EPA promulgate regulations 
requiring the control of HAP emissions from major sources and certain 
area sources. The control of HAP is achieved through promulgation of 
emission standards under sections 112(d) and (f) of the CAA and, in 
appropriate circumstances, work practice standards under section 112(h) 
of the CAA.
    An initial list of categories of major and area sources of HAP 
selected for regulation in accordance with section 112(c) of the CAA 
was published in the Federal Register on July 16, 1992 (57 FR 31576). 
Industrial boilers, commercial and institutional boilers, and process 
heaters are three of the listed 174 categories of sources. The listing 
was based on the Administrator's determination that they may reasonably 
be anticipated to emit several of the 188 listed HAP in quantities 
sufficient to designate them as major sources.


D. What Is the Relationship Between the Proposed Rule and Other 
Combustion Rules?


    The proposed rule regulates source categories covering industrial 
boilers, institutional and commercial boilers, and process heaters. 
These source categories potentially include combustion units that are 
already regulated by other MACT standards. Therefore, we are excluding 
from today's proposed rule any units that are already or will be 
subject to regulation under another MACT standard.
    The commercial and industrial solid waste incinerators (CISWI) 
standards (40 CFR 60, subparts CCCC and DDDD) regulate commercial and 
industrial nonhazardous solid waste incinerators. Sources subject to 
the CISWI rules are exempt from the requirements of the proposed rule.
    The utility HAP study Report to Congress provides information used 
to determine whether fossil fuel-fired utility boilers should be 
regulated in a future MACT standard. A fossil fuel-fired utility boiler 
is a fossil fuel-fired combustion unit with a heat input greater than 
25 megawatts that serves a generator producing electricity for sale. 
Fossil fuel-fired utility boilers are exempt from the proposed rule. 
Nonfossil fuel-fired utility boilers are covered by the proposed rule.
    The EPA's Office of Solid Waste is in the process of developing 
MACT based standards for hazardous waste boilers. Boilers burning 
hazardous waste are not included in the proposed rule.
    In 1986, EPA had codified new source performance standards (NSPS) 
for industrial boilers (40 CFR part 60, subparts Db and Dc) and revised 
portions of them in 1999. The NSPS regulates emissions of particulate 
matter (PM), sulfur dioxide, and nitrogen oxides from boilers 
constructed after June 19, 1984. Sources subject to the NSPS are still 
subject to the proposed rule because the proposed rule regulates 
sources of hazardous air pollutants while the NSPS does not. However, 
in developing the proposed rule for industrial/commercial/institutional 
boilers and process heaters, EPA minimized the monitoring requirements, 
testing requirements, and recordkeeping requirements to avoid 
duplicating requirements.
    Because of the broad applicability of the proposed rule due to the 
definition of a process heater, certain process heaters could appear to 
fit the applicability of another existing MACT rule. We have, 
therefore, included in the list of combustion units exempt from the 
proposed rule refining kettles subject to the secondary lead MACT rule 
(40 CFR 63, subpart X). This is one combustion unit meeting the 
definition of a process heater, that we are specifically aware of, that 
is covered by another MACT standard. Therefore, we are requesting 
comments on other process heaters that are already or will be subject 
to regulation under another MACT standard.


[[Page 1664]]


E. What Are the Health Effects of Pollutants Emitted From Industrial/
Commercial/Institutional Boilers and Process Heaters?


    Today's proposed rule protects air quality and promotes the public 
health by reducing emissions of some of the HAP listed in section 
112(b)(1) of the CAA. As noted above, emissions data collected during 
development of the proposed rule show that hydrogen chloride emissions 
represent the predominant HAP emitted by industrial boilers, accounting 
for 59 percent of the total HAP emissions. Industrial boilers and 
process heaters also emit lesser amounts of hydrogen fluoride, 
accounting for about 5 percent of total HAP emissions, and metals 
(arsenic, cadmium, chromium, mercury, manganese, nickel, and lead), 
accounting for about 4 percent of total HAP emissions. Exposure to 
these HAP is associated with a variety of adverse health effects. These 
adverse health effects include chronic health disorders (e.g., 
irritation of the lung, skin, and mucus membranes, effects on the 
central nervous system, and damage to the kidneys), and acute health 
disorders (e.g., lung irritation and congestion, alimentary effects 
such as nausea and vomiting, and effects on the kidney and central 
nervous system). We have classified two of the HAP as human carcinogens 
and three as probable human carcinogens. We do not know the extent to 
which the adverse health effects described above occur in the 
populations surrounding these facilities. However, to the extent the 
adverse effects do occur, today's proposed rule would reduce emissions 
and subsequent exposures.
1. Arsenic
    Acute (short-term) high-level inhalation exposure to arsenic dust 
or fumes has resulted in gastrointestinal effects (nausea, diarrhea, 
abdominal pain), and central and peripheral nervous system disorders. 
Chronic (long-term) inhalation exposure to inorganic arsenic in humans 
is associated with irritation of the skin and mucous membranes. Human 
data suggest a relationship between inhalation exposure of women 
working at or living near metal smelters and an increased risk of 
reproductive effects, such as spontaneous abortions. Inorganic arsenic 
exposure in humans by the inhalation route has been shown to be 
strongly associated with lung cancer, while ingestion of inorganic 
arsenic in humans has been linked to a form of skin cancer and also to 
bladder, liver, and lung cancer. The EPA has classified inorganic 
arsenic as a Group A, human carcinogen.
2. Cadmium
    The acute (short-term) effects of cadmium inhalation in humans 
consist mainly of effects on the lung, such as pulmonary irritation. 
Chronic (long-term) inhalation or oral exposure to cadmium leads to a 
build-up of cadmium in the kidneys that can cause kidney disease. 
Cadmium has been shown to be a developmental toxicant in animals, 
resulting in fetal malformations and other effects, but no conclusive 
evidence exists in humans. An association between cadmium exposure and 
an increased risk of lung cancer has been reported from human studies, 
but these studies are inconclusive due to confounding factors. Animal 
studies have demonstrated an increase in lung cancer from long-term 
inhalation exposure to cadmium. The EPA has classified cadmium as a 
Group B1, probable carcinogen.
3. Chromium
    Chromium may be emitted in two forms, trivalent chromium (chromium 
III) or hexavalent chromium (chromium VI). The respiratory tract is the 
major target organ for chromium VI toxicity, for acute (short-term) and 
chronic (long-term) inhalation exposures. Shortness of breath, 
coughing, and wheezing have been reported from acute exposure to 
chromium VI, while perforations and ulcerations of the septum, 
bronchitis, decreased pulmonary function, pneumonia, and other 
respiratory effects have been noted from chronic exposure. Limited 
human studies suggest that chromium VI inhalation exposure may be 
associated with complications during pregnancy and childbirth, while 
animal studies have not reported reproductive effects from inhalation 
exposure to chromium VI. Human and animal studies have clearly 
established that inhaled chromium VI is a carcinogen, resulting in an 
increased risk of lung cancer. The EPA has classified chromium VI as a 
Group A, human carcinogen.
    Chromium III is less toxic than chromium VI. The respiratory tract 
is also the major target organ for chromium III toxicity, similar to 
chromium VI. Chromium III is an essential element in humans, with a 
daily intake of 50 to 200 micrograms per day recommended for an adult. 
The body can detoxify some amount of chromium VI to chromium III. The 
EPA has not classified chromium III with respect to carcinogenicity.
4. Hydrogen Chloride
    Hydrogen chloride, also called hydrochloric acid, is corrosive to 
the eyes, skin, and mucous membranes. Acute (short-term) inhalation 
exposure may cause eye, nose, and respiratory tract irritation and 
inflammation and pulmonary edema in humans. Chronic (long-term) 
occupational exposure to hydrochloric acid has been reported to cause 
gastritis, bronchitis, and dermatitis in workers. Prolonged exposure to 
low concentrations may also cause dental discoloration and erosion. No 
information is available on the reproductive or developmental effects 
of hydrochloric acid in humans. In rats exposed to hydrochloric acid by 
inhalation, altered estrus cycles have been reported in females and 
increased fetal mortality and decreased fetal weight have been reported 
in offspring. The EPA has not classified hydrochloric acid for 
carcinogenicity.
5. Hydrogen Fluoride
    Acute (short-term) inhalation exposure to gaseous hydrogen fluoride 
can cause severe respiratory damage in humans, including severe 
irritation and pulmonary edema. Chronic (long-term) exposure to 
fluoride at low levels has a beneficial effect of dental cavity 
prevention and may also be useful for the treatment of osteoporosis. 
Exposure to higher levels of fluoride may cause dental fluorosis. One 
study reported menstrual irregularities in women occupationally exposed 
to fluoride. The EPA has not classified hydrogen fluoride for 
carcinogenicity.
6. Lead
    Lead is a very toxic element, causing a variety of effects at low 
dose levels. Brain damage, kidney damage, and gastrointestinal distress 
may occur from acute (short-term) exposure to high levels of lead in 
humans. Chronic (long-term) exposure to lead in humans results in 
effects on the blood, central nervous system (CNS), blood pressure, and 
kidneys. Children are particularly sensitive to the chronic effects of 
lead, with slowed cognitive development, reduced growth and other 
effects reported. Reproductive effects, such as decreased sperm count 
in men and spontaneous abortions in women, have been associated with 
lead exposure. The developing fetus is at particular risk from maternal 
lead exposure, with low birth weight and slowed postnatal 
neurobehavioral development noted. Human studies are inconclusive 
regarding lead exposure and cancer, while animal studies have reported 
an increase in kidney cancer from lead


[[Page 1665]]


exposure by the oral route. The EPA has classified lead as a Group B2, 
probable human carcinogen.
7. Manganese
    Health effects in humans have been associated with both 
deficiencies and excess intakes of manganese. Chronic (long-term) 
exposure to low levels of manganese in the diet is considered to be 
nutritionally essential in humans, with a recommended daily allowance 
of 2 to 5 milligrams per day. Chronic exposure to high levels of 
manganese by inhalation in humans results primarily in CNS effects. 
Visual reaction time, hand steadiness, and eye-hand coordination were 
affected in chronically-exposed workers. Manganism, characterized by 
feelings of weakness and lethargy, tremors, a mask-like face, and 
psychological disturbances, may result from chronic exposure to higher 
levels. Impotence and loss of libido have been noted in male workers 
afflicted with manganism attributed to inhalation exposures. The EPA 
has classified manganese in Group D, not classifiable as to 
carcinogenicity in humans.
8. Mercury
    Mercury exists in three forms: elemental mercury, inorganic mercury 
compounds (primarily mercuric chloride), and organic mercury compounds 
(primarily methyl mercury). Each form exhibits different health 
effects. Various major sources may release elemental or inorganic 
mercury; environmental methyl mercury is typically formed by biological 
processes after mercury has precipitated from the air.
    Acute (short-term) exposure to high levels of elemental mercury in 
humans results in CNS effects such as tremors, mood changes, and slowed 
sensory and motor nerve function. High inhalation exposures can also 
cause kidney damage and effects on the gastrointestinal tract and 
respiratory system. Chronic (long-term) exposure to elemental mercury 
in humans also affects the CNS, with effects such as increased 
excitability, irritability, excessive shyness, and tremors. The EPA has 
not classified elemental mercury with respect to cancer.
    Acute exposure to inorganic mercury by the oral route may result in 
effects such as nausea, vomiting, and severe abdominal pain. The major 
effect from chronic exposure to inorganic mercury is kidney damage. 
Reproductive and developmental animal studies have reported effects 
such as alterations in testicular tissue, increased embryo resorption 
rates, and abnormalities of development. Mercuric chloride (an 
inorganic mercury compound) exposure has been shown to result in 
forestomach, thyroid, and renal tumors in experimental animals. The EPA 
has classified mercuric chloride as a Group C, possible human 
carcinogen.
9. Nickel
    Nickel is an essential element in some animal species, and it has 
been suggested it may be essential for human nutrition. Nickel 
dermatitis, consisting of itching of the fingers, hand and forearms, is 
the most common effect in humans from chronic (long-term) skin contact 
with nickel.
    Respiratory effects have also been reported in humans from 
inhalation exposure to nickel. No information is available regarding 
the reproductive or developmental effects of nickel in humans, but 
animal studies have reported such effects. Human and animal studies 
have reported an increased risk of lung and nasal cancers from exposure 
to nickel refinery dusts and nickel subsulfide. Animal studies of 
soluble nickel compounds (i.e., nickel carbonyl) have reported lung 
tumors. The EPA has classified nickel refinery subsulfide as Group A, 
human carcinogens and nickel carbonyl as a Group B2, probable human 
carcinogen.


II. Summary of the Proposed Rule


A. What Source Categories and Subcategories Are Affected by the 
Proposed Rule?


    The proposed rule affects industrial boilers, institutional and 
commercial boilers, and process heaters. In the proposed rule process 
heaters are defined as units in which the combustion gases do not 
directly come into contact with process gases in the combustion chamber 
(e.g., indirect fired). Boiler means an enclosed device using 
controlled flame combustion and having the primary purpose of 
recovering thermal energy in the form of steam or hot water. Combustion 
units are not subject to the proposed rule simply by virtue of having a 
waste heat boiler. A waste heat boiler (or heat recovery steam 
generator) is a device that recovers normally unused energy and 
converts it to usable heat. Emissions from a combustion unit with a 
waste heat boiler are regulated by the applicable standards for the 
particular type of combustion unit. For example, emissions from a 
commercial or industrial solid waste incineration unit, or other 
incineration unit with a waste heat boiler are regulated by standards 
established under section 129 of the CAA.
    Hot water heaters also are not regulated under today's proposed 
rule. A hot water heater is a closed vessel in which water is heated by 
combustion of gaseous fuel and is withdrawn for use external to the 
vessel at pressures not exceeding 160 pounds per square inch gauge and 
water temperatures not exceeding 210 degree Fahrenheit.


B. What Pollutants Are Emitted?


    Boilers and process heaters emit PM, volatile organic compounds, 
and hazardous air pollutants, depending on the material burned. Solid 
and liquid fuel-fired units emit metals, halogenated compounds and 
organic compounds. Gas fuel-fired units emit mostly organic compounds.


C. What Is the Affected Source?


    The affected source is each individual industrial, commercial, or 
institutional boiler or process heater located at a major facility. The 
affected source does not include units that are municipal waste 
combustors (40 CFR part 60, subparts AAAA, BBBB, Eb or Cb), medical 
waste incinerators (40 CFR part 60, subpart Ce and Ec), fossil fuel-
fired electric utility steam generating units, commercial and 
industrial solid waste incineration units (40 CFR part 60, subparts 
CCCC or DDDD), recovery boilers or furnaces (40 CFR part 63, subpart 
MM), ethylene cracking furnaces (40 CRF part 63, subpart YY), or 
hazardous waste combustion units required to have a permit under 
section 3005 of the Solid Waste Disposal Act or are subject to 40 CFR 
part 63, subpart EEE.


D. Does the Proposed Rule Apply to Me?


    The proposed rule applies to you if you own or operate a boiler or 
process heater at a major source meeting the requirements discussed 
previously in this preamble. A major source of HAP emissions is any 
stationary source or group of stationary sources located within a 
contiguous area and under common control that emits or has the 
potential to emit any single HAP at a rate of 10 tons or more per year 
or any combination of HAP at a rate of 25 tons or more a year.


E. What Emission Limitations and Work Practice Standards Must I Meet?


    You must meet the emission limits and work practice standards for 
the subcategories in Table 1 of this preamble for each of the 
pollutants listed. Emission limits and work practice standards were 
developed for new and existing sources; and for large, small, and 
limited use solid, liquid, and gas fuel-fired units. Large units are 
those


[[Page 1666]]


watertube boilers and process heaters with heat input capacities 
greater than 10 million British thermal units per hour (MMBtu/hr). 
Small units are any firetube boilers or any boiler and process heater 
with heat input capacities less than or equal to 10 MMBtu/hr. Limited 
use units are those large units with capacity utilizations less than or 
equal to 10 percent as required in a federally enforceable permit.
    If your new or existing boiler or process heater is permitted to 
burn a solid fuel (either as a primary fuel or a backup fuel), or any 
combination of solid fuel with liquid or gaseous fuel, the unit is in 
one of the solid subcategories. If your new or existing boiler or 
process heater burns a liquid fuel, or a liquid fuel in combination 
with a gaseous fuel, the unit is in one of the liquid subcategories. If 
your new or existing boiler or process heater burns a gaseous fuel 
only, the unit is in the gas subcategory.


                                  Table 1.--Emission Limits and Work Practice Standards for Boilers and Process Heaters
                                                       [Pounds per million British thermal units]
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                                Total       Hydrogen
                 Source                           Subcategory           Particulate    or     selected      chloride    Mercury (Hg)    Carbon Monoxide
                                                                        matter (PM)            metals         (HCl)                   (CO)(ppm@3%oxygen)
--------------------------------------------------------------------------------------------------------------------------------------------------------
New Boiler, or Process Heater...........  Solid Fuel, Large Unit.....         0.026     or        0.0001        0.02        0.000003              400
                                          Solid Fuel, Small Unit.....         0.026     or        0.0001        0.02        0.000003  ..................
                                          Solid Fuel, Limited Use....         0.026     or        0.0001        0.02        0.000003              400
                                          Liquid Fuel, Large Unit....         0.03   .....  ............        0.0005  ............              400
                                          Liquid Fuel, Small Unit....         0.03   .....        0.0009  ............  ............
                                          Liquid Fuel, Limited Use...         0.03   .....  ............        0.0009  ............              400
                                          Gaseous Fuel Large Unit....  ............  .....  ............  ............  ............              400
                                          Gaseous Fuel Small Unit....  ............  .....  ............  ............
                                          Gaseous Fuel Limited Use...  ............  .....  ............  ............  ............              400
Existing Boiler or Process Heater.......  Solid Fuel, Large Unit.....         0.07      or        0.001         0.09        0.000007  ..................
                                          Solid Fuel, Small Unit.....  ............  .....  ............  ............  ............  ..................
                                          Solid Fuel, Limited Used...         0.2       or        0.001   ............  ............  ..................
                                          Liquid Fuel, Large Unit....  ............  .....  ............  ............  ............  ..................
                                          Liquid Fuel, Small Unit....  ............  .....  ............  ............  ............  ..................
                                          Liquid Fuel, Limited Use...  ............  .....  ............  ............  ............  ..................
                                          Gaseous Fuel...............  ............  .....  ............  ............  ............  ..................
--------------------------------------------------------------------------------------------------------------------------------------------------------


    For solid fuel-fired boilers or process heaters, we are proposing 
to allow sources to choose one of two emission limit options: (1) 
Existing and new affected sources may choose to limit PM emissions to 
the level listed in Table 1 of this preamble or (2) existing and new 
affected sources may choose to limit total selected metals emissions to 
the level listed in Table 1 of this preamble.
    If you do not use an add-on control or use an add-on control other 
than a wet scrubber, you must maintain opacity level to less than or 
equal to the level established during the compliance test for mercury 
and PM or total selected metals, and maintain the fuel chlorine content 
to less than or equal to the operating level established during the HCl 
compliance test.
    If you use a wet scrubber, you must maintain the minimum pH, 
pressure drop and liquid flow-rate above the operating levels 
established during the performance tests.
    If you use a dry scrubber, you must maintain opacity level and the 
minimum sorbent injection rate established during the performance test.
    If you use an electrostatic precipitator (ESP) in combination with 
a wet scrubber and cannot monitor the opacity, you must maintain the 
average secondary current and voltage or total power input established 
during the performance test.
    There is an alternative compliance procedure and operating limit 
for meeting the total selected metals emission limit option or the 
mercury emission limit option. If you have no control or do not want to 
take credit of metals reductions with your existing control device, and 
can show that total metals in the fuel would be less than the metals 
emission level, then you can monitor the metals fuel analysis to meet 
the metals emissions limitations. Similarly, if you do not have an 
emission control device or you otherwise would rather comply by 
limiting the mercury input at your facility, and can show that mercury 
in the fuel would be less than the mercury emission level, then you can 
monitor the mercury fuel analysis to meet the mercury emission 
limitations.
    If your unit is a new source in the large or limited use 
subcategories, it must meet a carbon monoxide (CO) emission limit of 
400 parts per million corrected to 3 percent oxygen. If your new or 
existing source is controlled with a fabric filter, then you must 
install a bag leak detection system such that the bag detection system 
alarm does not sound more than 5 percent of the operating time during a 
6-month period.


F. What Are the Testing and Initial Compliance Requirements?


    As the owner or operator of a new or existing boiler or process 
heater, you must conduct performance tests to demonstrate compliance 
with any applicable emission limits. The applicable emission limits 
and,


[[Page 1667]]


therefore, the required performance tests are different depending on 
the subcategory classification of the unit. Existing units in the small 
solid fuel subcategory and in any of the liquid or gaseous fuel 
subcategories do not have applicable emission limits and, therefore, 
are not required to conduct stack tests. Other units are required to 
conduct the following compliance tests where applicable:
    (1) Conduct initial and annual stack tests to determine compliance 
with the PM emission limits using EPA Method 5 or Method 17 in appendix 
A to part 60 of this chapter.
    (2) Affected sources in the solid fuel subcategories may choose to 
comply with an alternative total selected metals emission limit instead 
of PM. Sources would then conduct initial and annual stack tests to 
determine compliance with the total selected metals emission limit 
using EPA Method 29 in appendix A to part 60 of this chapter.
    (3) Conduct initial and annual stack tests to determine compliance 
with the mercury emission limits using EPA method 29 in appendix A to 
part 60 of this chapter (for boilers with rated heat input capacities 
of less than 250 MMBtu per hour) or the draft ASTM Z65907, ``Standard 
Method for Both Speciated and Elemental Mercury Determination,'' (for 
boilers with rated heat input capacities of greater than 250 MMBtu per 
hour).
    (4) Conduct initial and annual stack tests to determine compliance 
with the HCl emission limits using EPA Method 26 in appendix A to part 
60 of this chapter (for boilers without wet scrubbers) or EPA Method 
26A in appendix A to part 60 of this chapter (for boilers with wet 
scrubbers).
    (5) Use EPA Method 19 in appendix A to part 60 of this chapter to 
convert measured concentration values to pound per million British 
thermal units (Btu) values.
    (6) For new units in any of the liquid fuel subcategories that do 
not burn residual oil, instead of conducting an initial compliance test 
you may submit a signed statement in the Notification of Compliance 
Status report that indicates that you only burn liquid fossil fuels 
other than residual oil.
    As part of the initial compliance demonstration, you must monitor 
specified operating parameters during the initial performance tests 
that demonstrate compliance with the PM (or metals), mercury, and HCl 
emission limits. You must calculate the average parameter values 
measured during each 1-hour test run over the 3-hour performance test. 
The minimum or maximum of the three average values (depending on the 
parameter measured) for each applicable parameter is established as a 
site-specific operating limit. The applicable operating parameters for 
which operating limits must be established are based on the emissions 
limits applicable to your unit as well as the types of add-on controls 
on the unit. A summary of the operating limits that must be established 
for the various types of the following units:
    (1) For boilers and process heaters without wet scrubbers that must 
comply with the mercury emission limit and either a PM emission limit 
or a total selected metals emission limit, you must measure opacity 
during the performance test and calculate the 6-minute averages. The 
maximum 1-hour average measured establishes your site-specific opacity 
operating limit. Or, if the unit is controlled with a fabric filter, 
instead of setting an opacity operating limit, the fabric filter must 
be operated such that the required bag leak detection system alarm does 
not sound more than 5 percent of the operating time during any 6-month 
period.
    (2) For boilers and process heaters without wet or dry scrubbers 
that must comply with an HCl emission limit, you must measure the 
average chlorine content level in the input fuel(s) during the HCl 
performance test. This is your maximum chlorine input operating limit. 
If you plan to burn a new fuel, a fuel from a new mixture, or a fuel 
from a new supplier than what was burned during the initial performance 
test, then you must recalculate the maximum chlorine input anticipated 
from the new fuels based on supplier data or own fuel analysis. If the 
results of recalculating the chlorine input exceeds the average 
chlorine content level established during the initial test then you 
must conduct a new performance test to demonstrate compliance with the 
HCl emission limit.
    (3) For boilers and process heaters with wet scrubbers that must 
comply with a mercury, PM and/or an HCl emission limit, you must 
measure pressure drop and liquid flow-rate of the scrubber during the 
performance test, and calculate the average value for each test run. 
The minimum test run average establishes your site-specific pressure 
drop and liquid flow-rate operating levels. If different average 
parameter levels are measured during the mercury, PM (or metals) and 
HCl tests, the highest of the average values becomes your site-specific 
operating limit. If you are complying with an HCl emission limit, you 
must measure pH during the performance test for HCl and determine the 
average for each test run and the minimum value for the performance 
test. This establishes your minimum pH operating limit.
    (4) For boilers and process heaters with dry scrubbers that must 
comply with a PM or mercury emission limit, you must measure opacity 
during the PM performance test as described above. If you must also 
comply with an HCl emission limit, you must measure the sorbent 
injection rate during the performance test for HCl, and calculate the 
average for each test run. The minimum test run average established 
during the performance test is your site-specific minimum sorbent 
injection rate operating limit.
    (5) For boilers and process heaters with fabric filters in 
combination with wet scrubbers that must comply with a mercury emission 
limit, PM emission limit and/or an HCl emission limit, you must measure 
the pH, pressure drop, and liquid flow-rate of the wet scrubber during 
the performance test and calculate the average value for each test run. 
The minimum test run average establishes your site-specific pH, 
pressure drop, and liquid flow-rate operating limits for the wet 
scrubber. Furthermore, the fabric filter must be operated such that the 
bag leak detection system alarm does not sound more than 5 percent of 
the operating time during any 6-month period.
    (6) For boilers and process heaters with ESP in combination with 
wet scrubbers that must comply with a mercury, PM and/or an HCl 
emission limit, you must measure the pH, pressure drop, and liquid 
flow-rate of the wet scrubber during the HCl performance test and you 
must measure the voltage and current of the ESP collection plates 
during the mercury and PM (or metals) performance test. Calculate the 
average value of these parameters for each test run. The minimum test 
run averages establish your site-specific minimum pH, pressure drop, 
and liquid flow-rate operating limit for the wet scrubber and the 
minimum voltage and current operating limits for the ESP plates.
    (7) For boilers that choose to comply with the alternative total 
selected metals emission limit instead of PM and have either no add-on 
controls or add-on controls for which you do not want to take credit 
for any emission reduction of metals, you must measure the total 
selected metals content of the inlet fuel that was burned during the 
total selected metals performance test. This value is your maximum fuel 
inlet metals content operating limit. If you plan to burn a new fuel, a 
fuel from a new mixture, or a fuel from a new supplier than what was 
burned during the initial performance test, then you must


[[Page 1668]]


recalculate the maximum metals input anticipated from the new fuels 
based on supplier data or own fuel analysis. If the results of 
recalculating the metals input exceeds the average metals content level 
established during the initial test then you must conduct a new 
performance test to demonstrate compliance with the alternate total 
selected metals emission limit.
    (8) For boilers that choose to demonstrate compliance with the 
mercury emission limit on the basis of fuel analysis and have no add-on 
controls or add-on controls for which you do not want to take credit 
for any emission reduction of mercury, you must measure the mercury 
content of the inlet fuel that was burned during the mercury 
performance test. This value is your maximum fuel inlet mercury 
operating limit. If you plan to burn a new fuel, a fuel from a new 
mixture, or a fuel from a new supplier than what was burned during the 
initial performance test, then you must recalculate the maximum mercury 
input anticipated from the new fuels based on supplier data or own fuel 
analysis. If the results of recalculating the mercury input exceeds the 
average mercury content level established during the initial test then 
you must conduct a new performance test to demonstrate compliance with 
the mercury emission limit.
    (9) For new boilers and process heaters in any of the large or 
limited use subcategories, you must monitor CO during the performance 
tests for PM (or metals) and/or HCl to demonstrate that average CO 
emissions are at or below an exhaust concentration of 400 parts per 
million (ppm) by volume on a dry basis corrected to 3 percent oxygen.


G. What Are the Continuous Compliance Requirements?


    To demonstrate continuous compliance with the emission limitations, 
you must monitor and comply with the applicable site-specific operating 
limits established during the following performance tests:
    (1) For boilers and process heaters without wet scrubbers that must 
comply with a mercury emission limit and either a PM emission limit or 
a total selected metals emission limit, you must continuously monitor 
opacity and maintain the 3-hour block average at or below your site-
specific opacity operating limit. Or, if the unit is controlled with a 
fabric filter, instead of continuous monitoring opacity, the fabric 
filter must be continuously operated such that the bag leak detection 
system alarm does not sound more than 5 percent of the operating time 
during any 6-month period.
    (2) For boilers and process heaters without wet or dry scrubbers 
that must comply with an HCl emission limit, you must maintain daily 
records of fuel use that demonstrate that you have burned no new fuels 
such that you have maintained the fuel chlorine content level at or 
below your site-specific maximum chlorine input operating limit. If you 
plan to burn a new fuel, a fuel from a new mixture, or a fuel from a 
new supplier than what was burned during the initial performance test, 
then you must recalculate the maximum chlorine input anticipated from 
the new fuels based on supplier data or own fuel analysis. If the 
results of recalculating the chlorine input exceeds the average 
chlorine content level established during the initial test then you 
must conduct a new performance test to demonstrate continuous 
compliance with the HCl emission limit.
    (3) For boilers and process heaters with wet scrubbers that must 
comply with a mercury, PM and/or an HCl emission limit, you must 
monitor pressure drop and liquid flow-rate of the scrubber and maintain 
the 3-hour block averages at or above the operating limits established 
during the performance test. You must monitor the pH of the scrubber 
and maintain the 3-hour block average at or above the operating limit 
established during the performance test to demonstrate continuous 
compliance with the HCl emission limits.
    (4) For boilers and process heaters with dry scrubbers that must 
comply with a PM or mercury emission limit, you must monitor and 
maintain opacity levels as described above to demonstrate continuous 
compliance with the PM emission limits. If you must also comply with an 
HCl emission limit, you must continuously monitor the sorbent injection 
rate and maintain it at or above the operating limits established 
during the HCl performance test.
    (5) For boilers and process heaters with fabric filters in 
combination with wet scrubbers, you must monitor the pH, pressure drop, 
and liquid flow-rate of the wet scrubber and maintain the levels at or 
above the operating limits established during the HCl performance test. 
You must also maintain the operation of the fabric filter such that the 
bag leak detection system alarm does not sound more than 5 percent of 
the operating time during any 6-month period.
    (6) For boilers and process heaters with ESP in combination with 
wet scrubbers that must comply with a mercury, PM and/or an HCl 
emission limit, you must monitor the pH, pressure drop, and liquid 
flow-rate of the wet scrubber and maintain the 3-hour block averages at 
or above the operating limits established during the HCl performance 
test and you must monitor the voltage and current of the ESP collection 
plates and maintain the 3-hour block averages at or above the operating 
limits established during the mercury or PM (or metals) performance 
test.
    (7) For boilers that choose to comply with the alternative total 
selected metals limit instead of PM emission limit based on fuel 
analysis rather than on performance testing, you must maintain daily 
fuel records that demonstrate that you burned no new fuels or fuels 
from a new supplier such that the total selected metals content of the 
inlet fuel was maintained at or below your maximum fuel inlet metals 
content operating limit set during the metals performance test. If you 
plan to burn a new fuel, a fuel from a new mixture, or a fuel from a 
new supplier than what was burned during the initial performance test, 
then you must recalculate the maximum metals input anticipated from the 
new fuels based on supplier data or own fuel analysis. If the results 
of recalculating the metals input exceeds the average metals content 
level established during the initial test then you must conduct a new 
performance test to demonstrate continuous compliance with the 
alternate selected metals emission limit.
    (8) For boilers that choose to comply with the mercury emission 
limit based on fuel analysis rather than on performance testing, you 
must maintain daily fuel records that demonstrate that you burned no 
new fuels or fuels from a new supplier such that the total selected 
mercury content of the inlet fuel was maintained at or below your 
maximum fuel inlet metals content operating limit set during the 
mercury performance test. If you plan to burn a new fuel, a fuel from a 
new mixture, or a fuel from a new supplier than what was burned during 
the initial performance test, then you must recalculate the maximum 
mercury input anticipated from the new fuels based on supplier data or 
own fuel analysis. If the results of recalculating the mercury input 
exceeds the average mercury content level established during the 
initial test then you must conduct a new performance test to 
demonstrate continuous compliance with the mercury emission limit.
    (9) For new boilers and process heaters in any of the large or 
limited use subcategories, you must continuously monitor CO and 
maintain the average CO emissions at or below 400 ppm by


[[Page 1669]]


volume on a dry basis corrected to 3 percent oxygen to demonstrate 
compliance with the work practice standards. Upon detecting an 
excursion or exceedance, you must restore operation of the unit to its 
normal or usual manner of operation as expeditiously as practicable in 
accordance with good air pollution control practices for minimizing 
emissions. The response shall include minimizing the period of any 
startup, shutdown or malfunction and taking any necessary corrective 
actions to restore normal operation and prevent the likely recurrence 
of the cause of an excursion or exceedance. Such actions may include 
initial inspections and evaluation, recording that operations returned 
to normal without operator action, or any necessary follow-up actions 
to return operation to below the work practice standard.
    If a control device other than the ones specified in this section 
is used to comply with the proposed rule, you must establish site-
specific operating limits and establish appropriate continuous 
monitoring requirements, as approved by the Administrator.


H. What Are the Notification, Recordkeeping and Reporting Requirements?


    You must keep the following records:
    (1) All reports and notifications submitted to comply with the 
proposed rule.
    (2) Continuous monitoring data as required in the proposed rule.
    (3) Each instance in which you did not meet each emission limit and 
each operating limit, including periods of startup, shutdown, and 
malfunction (i.e., deviations from the proposed rule).
    (4) Daily hours of operation by each source.
    (5) Total fuel use by each affected source electing to comply with 
an emission limit based on fuel analysis for each 30-day period along 
with a description of the fuel, the total fuel usage amounts and units 
of measure, and information on the supplier and original source of the 
fuel.
    (6) Calculations and supporting information of chlorine fuel input, 
as required in the proposed rule.
    (7) Calculations and supporting information of total selected 
metals and mercury fuel input, as required in the proposed rule, if 
applicable.
    (8) A signed statement, as required in the proposed rule, 
indicating you burned no new fuels, no fuels from a new supplier, or no 
new fuel mixture or the recalculation of chlorine input to demonstrate 
that the new fuel, new mixture, new source still meets chlorine fuel 
input levels.
    (9) A signed statement, as required in the proposed rule, 
indicating you burned no new fuels, no fuels from a new supplier, or no 
new fuel mixture or the recalculation of total selected metals fuel 
input to demonstrate that the new fuel, new fuel mixture, or fuel from 
a new source still meets the total selected metals fuel input levels.
    (10) A signed statement, as required in the proposed rule, 
indicating you burned no new fuels, no fuels from a new supplier, or no 
new fuel mixture or the recalculation of mercury fuel input to 
demonstrate that the new fuel, new fuel mixture, or fuel from a new 
source still meets the mercury fuel input levels.
    (11) A copy of the results of all performance tests, fuel analysis, 
opacity observations, performance evaluations, or other compliance 
demonstrations conducted to demonstrate initial or continuous 
compliance with the proposed rule.
    (12) A copy of any Federally enforceable permit that limits the 
annual capacity factor of the source to less than or equal to 10 
percent.
    (13) A copy of your site-specific startup, shutdown, and 
malfunction plan.
    (14) A copy of your site-specific monitoring plan developed for the 
proposed rule, if applicable.
    You must submit the following reports and notifications:
    (1) Notifications required by the General Provisions.
    (2) Initial Notification no later than 120 calendar days after you 
become subject to this subpart.
    (3) Notification of Intent to conduct performance tests and/or 
compliance demonstration at least 60 calendar days before the 
performance test and/or compliance demonstration is scheduled.
    (4) Notification of Compliance Status 60 calendar days following 
completion of the performance test and/or compliance demonstration.
    (5) Compliance reports semi-annually.


III. Rationale of the Proposed Rule


A. How Did EPA Determine Which Pollution Sources Would Be Regulated 
Under the Proposed Rule?


    The proposed rule regulates source categories covering industrial 
boilers, institutional and commercial boilers, and process heaters. 
These source categories potentially include combustion units that are 
already regulated by other MACT standards. Therefore, we are excluding 
from today's proposed rule any units that are already or will be 
subject to regulation under another MACT standard. A list of combustion 
units excluded from the proposed rule is discussed previously in this 
preamble. The CAA specifically requires that fossil fuel-fired steam 
generating units of more than 25 megawatts that produce electricity for 
sale (i.e., utility boilers) be reviewed separately by EPA. 
Consequently, the proposed rule does not regulate fossil fuel-fired 
utility boilers greater than 25 megawatts, but does regulate fossil 
fuel-fired units less than 25 megawatts and all nonfossil fuel-fired 
utility boilers. The proposed rule also does not regulate emissions 
from combustion units with waste heat boilers, unless such units would 
otherwise be subject to the emission limitations in today's proposed 
rule. For example, emissions from any commercial or industrial solid 
waste incinerator (CISWI) or other incinerator unit that has a waste 
heat boiler will be covered by regulations promulgated under section 
129 of the CAA.
    During the ICCR FACA, the scope of the process heater source 
category was limited to regulate only indirect-fired units. Direct-
fired units are covered in other MACT standards or rulemakings 
pertaining to industrial process operations. For example, lime kilns 
are covered by the Pulp and Paper NESHAP (40 CFR part 63, subpart S). 
Indirect-fired process heaters are similar to boilers in fuel use, 
emissions, and applicable controls, and, therefore, it is appropriate 
for EPA to combine this category of units with industrial, commercial 
and institutional boilers for purposes of developing emission 
standards.
    Also during the ICCR FACA process, EPA received comments from 
stakeholders regarding the potential for the proposed rule to regulate 
small hot water heaters located at major source facilities. Many 
industrial facilities have office buildings located onsite which use 
hot water heaters. Such hot water heaters, by their design and 
operation, could be considered boilers. However, since hot water 
heaters generally are small and use natural gas as fuel, their 
emissions are negligible compared to the emissions from the industrial 
operations that make such facilities major sources, and compared to 
boilers that are used for industrial, commercial, or institutional 
purposes. Moreover, such hot water heaters are more appropriately 
described as residential-type boilers, not industrial, commercial or 
institutional boilers. Consequently, we are including a definition of 
hot water heaters that includes fuel, size, pressure and temperature 
limitations that we believe are appropriate to


[[Page 1670]]


distinguish between residential-type units and industrial, commercial 
or institutional units. Therefore, the proposed rule regulates 
industrial, commercial, and institutional boilers and process heaters 
located at major source facilities but excludes residential-type hot 
water heaters.
    The Clean Air Act allows EPA to divide source categories into 
subcategories when differences between given types of units lead to 
corresponding differences in the nature of emissions and the technical 
feasibility of applying emission control techniques. The design, 
operating, and emissions information that EPA has reviewed indicates 
the need to subcategorize boilers and process heaters based on the 
physical state of the fuel burned, i.e., solid, liquid, or gas. Data 
indicate that there are significant design and operational differences 
between units that burn solid, liquid and gaseous fuels.
    Boiler systems are designed for specific fuel types and will 
encounter problems if a fuel with characteristics other than those 
originally specified is fired. While many boilers in the population 
database are indicated to co-fire liquids or gases with solid fuels, in 
actuality most of these commonly use fuel oil or natural gas as a 
startup fuel only. Other co-fired units are specifically designed to 
fire combinations of solids, liquids, and gases. Changes to the fuel 
type (solid, liquid, or gas) would require extensive changes to the 
fuel handling and feeding system (e.g., a stoker using wood as fuel 
would need to be redesigned to handle fuel oil or gaseous fuel). 
Additionally, the burners and combustion chamber would need to be 
redesigned and modified to handle different fuel types and account for 
increases or decreases in the fuel volume and shape. In some cases, the 
changes may reduce the capacity and efficiency of the boiler or process 
heater. An additional effect of these changes would be extensive 
retrofit costs.
    Emissions from boilers and process heaters burning solids, liquids, 
and gaseous fuels will also differ. Boilers and process heaters emit a 
number of different types of HAP emissions. In general, their formation 
is dependent upon the composition of the fuel. The combustion quality 
and temperature may also play an important role. The fuel dependent HAP 
emissions from boilers and process heaters are metals, including 
mercury, and acid gases. These fuel dependent HAP emissions generally 
can be controlled by either changing the fuel property before 
combustion or by removing the HAP from the flue gas after combustion. 
Organic HAP, on the other hand, are formed from incomplete combustion 
and are much less influenced by the characteristics of the fuel being 
burned. The degree of combustion may be greatly influenced by three 
general factors: time, turbulence, and temperature. These factors are a 
function of the design of the boiler or process heater which is 
dependent in part on the type of fuel being burned.
    Solid fuel-fired units will emit larger amounts of PM and metals 
depending on the solid fuel burned. Liquid and gaseous fuel-fired units 
generally emit larger amounts of organic HAP. Because these different 
types of units have different emission characteristics which may 
influence the feasibility of effectiveness of emission control, they 
should be regulated separately (i.e., subcategorized). Thus, these 
categories appropriately identify distinctly different types of units 
subject to regulation.
    Accordingly, EPA decided to subcategorize boilers and process 
heaters into solid, liquid and gaseous fuel subcategories in order to 
account for these differences in emissions and applicable controls. The 
solid fuel subcategory includes boilers and process heaters burning any 
amount of solid fuel (including units burning a combination of solid 
fuel and liquid or gaseous fuel). The gaseous fuel subcategory includes 
units only burning gaseous fuel. The liquid fuel subcategory includes 
all remaining boilers and process heaters.
    Small boilers and process heaters were also identified as a 
subcategory. These small units typically are package units having 
capacities less than 10 MMBtu/hr heat input or use a combustor design 
(i.e., firetube or cast iron) which is not common in large units. Large 
boilers generally are field-erected using the watertube combustor 
design with capacities above 10 MMBtu/hr. As discussed above, the 
design of the boiler or process heater will influence the completeness 
of the combustion process which will influence the formation of organic 
HAP emissions. The vast majority of these small units use natural gas 
as fuel. Additionally, most existing State and Federal regulations for 
boilers and process heaters do not regulate units with a heat input 
capacity of less than 10 MMBtu/hr, due to their low emissions. 
Consequently, we decided to further subcategorize boilers and process 
heaters within each fuel category by creating subcategories for large 
units (watertube boilers and process heaters greater than 10 MMBtu/hr 
capacity) and small units (all firetube boilers and boilers and process 
heaters of any other type with less than or equal to 10 MMBtu/hr 
capacity).
    A review of the information gathered on boilers also shows that a 
number of units operate as backup, emergency, or peaking units that 
operate infrequently. Back-up or emergency units only operate if 
another boiler that is the regular source of energy or steam is not 
operating (for example due to a shutdown for maintenance and repair). 
Peaking units operate only during peak energy use periods, typically in 
the summer months. The boiler database indicates that these 
infrequently operated units typically operate 10 percent of the year or 
less. These limited use boilers, when called upon to operate, must 
respond without failure and without lengthy periods of startup. While 
these are potential sources of emissions, and it is appropriate for EPA 
to address them in the proposal, the Agency believes that their use and 
operation are different compared to typical industrial, commercial, and 
institutional boilers. Consequently, we decided that such limited use 
units should have their own subcategory. Therefore, the proposed rule 
has subcategories for boilers and process heaters having a capacity 
utilization of less than 10 percent.
    In summary, we have identified nine subcategories of boilers and 
process heaters located at major sources: (1) Large solid fuel-fired 
boilers and process heaters (sizes greater than 10 MMBtu/hr), (2) large 
liquid fuel-fired boilers and process heaters (sizes greater than 10 
MMBtu/hr), (3) large gaseous fuel-fired boilers and process heaters 
(sizes greater than 10 MMBtu/hr), (4) small solid fuel-fired boilers 
and process heaters (firetubes or any unit less than or equal to 10 
MMBtu/hr), (5) small liquid fuel-fired boilers and process heaters 
(sizes less than or equal to 10 MMBtu/hr), (6) small gaseous fuel-fired 
boilers and process heaters (sizes less than or equal to 10 MMBtu/hr), 
(7) limited use solid fuel-fired boilers and process heaters (large 
units with capacity utilization less than or equal to 10 percent), (8) 
limited use liquid fuel-fired boilers and process heaters (large units 
with capacity utilization less than or equal to 10 percent), and (9) 
limited use gaseous fuel-fired boilers and process heaters (large units 
with capacity utilization less than or equal to 10 percent).


B. How Did EPA Select the Format for the Proposed Rule?


    The proposed rule includes emission limits for PM, selected 
metallic HAP,


[[Page 1671]]


mercury, and HCl for six of the nine subcategories. The selection of 
emission limitations as the format for the proposed rule provides 
flexibility for the regulated community by allowing a regulated source 
to choose any control technology or technique to meet the emission 
limits, rather than requiring each unit to use a prescribed method that 
may not be appropriate in each case. This is particularly relevant for 
boilers and process heaters, because they can burn many different types 
of fuels with greatly varying emission profiles and owners need 
flexibility to use the control devices that are best for their 
particular emission characteristics.
    The EPA selected an outlet emission rate format because outlet data 
are available for boilers and process heaters that use the control 
techniques that provide the greatest reduction in HAP emissions. The 
individual limits reflect the achievable performance of boilers and 
process heaters using the appropriate controls for each type of 
emissions.
    The EPA is proposing numerical emission rate limits as a mass of 
pollutant emitted per heat energy input to the boiler or process 
heater. The most typical units for the limits are pounds of pollutant 
emitted per million Btu of heat input. The mass per heat input units 
are consistent with other Federal and many State boiler regulations and 
allows easy comparison between such requirements. Additionally, the 
proposed rule contains an option to monitor inlet chlorine, mercury, 
and metals content in the fuel to meet outlet emission rate limits. 
This option can only be done on a mass basis.
    The EPA considered percent reduction and outlet concentration as 
alternative formats for the pollutants regulated. However, an outlet 
concentration limit could not be accurately correlated to the chlorine 
content in the inlet fuel. An outlet concentration limit would also not 
be consistent with the format of other regulations. Affected units 
would already be complying with a mass per heat input limit, so EPA did 
not believe that a concentration limit would provide any additional 
benefits or flexibility. Additionally, data were insufficient to 
determine percent reductions that control devices achieve. Furthermore, 
a percent reduction requirement would limit the flexibility of the 
regulated community by requiring the use of a control device. 
Therefore, neither alternative was selected as the format for the 
proposed rule. The EPA requests comments on the appropriateness of 
percent reduction requirements and outlet concentration limit 
requirements, and any data upon which those requirements could be 
based.
    Boilers and process heaters can emit a wide variety of compounds, 
depending on the fuel burned. The boiler emissions test database lists 
over 100 possible HAP. Because of the large number of HAP potentially 
present and the disparity in the quantity and quality of the emissions 
information available, EPA grouped the HAP into four common categories: 
mercury, non-mercury metallic HAP, inorganic HAP, and organic HAP. In 
general, the pollutants within each group have similar characteristics 
and can be controlled with the same techniques. For example, non-
mercury metallic HAP can be controlled with PM controls. The EPA chose 
to look at mercury separately from other metallic HAP due to its 
different chemical characteristics and applicable controls.
    Next, EPA identified compounds that could be used as surrogates for 
all the compounds in each pollutant category. For the non-mercury 
metallic HAP, EPA chose to use PM as a surrogate. Most, if not all, 
non-mercury metallic HAP emitted from combustion sources will appear on 
the flue gas fly-ash. Therefore, the same control techniques that would 
be used to control the fly-ash PM will control non-mercury metallic 
HAP. Particulate matter was also chosen instead of specific metallic 
HAP because all fuels do not emit the same type and amount of metallic 
HAP but most generally emit PM that includes some amount and 
combination of metallic HAP. The use of PM as a surrogate will also 
eliminate the cost of performance testing to comply with numerous 
standards for individual metals.
    However, the Agency is sensitive to the fact that some sources that 
burn fuels containing very little metals, but would have sufficient PM 
emissions to require control under the PM provisions of the proposed 
rule. In such cases, PM would not be an appropriate surrogate for 
metallic HAP. Therefore, the Agency is also proposing an alternative 
metals emission limit. A source may choose to comply with the 
alternative metals emissions limit instead of the PM limit to meet the 
proposed rule. The metals emission limit is for the sum of emissions of 
eight selected metals: arsenic, beryllium, cadmium, chromium, lead, 
manganese, nickel, and selenium. The eight represent the most common 
and the largest emitted metallic HAP from boilers and process heaters.
    For inorganic HAP, EPA chose to use HCl as a surrogate. The 
emissions test information available to EPA indicate that the primary 
inorganic HAP emitted from boilers and process heaters are acid gases, 
with HCl present in the largest amounts. Other inorganic compounds 
emitted are found in much smaller quantities. Also, control 
technologies that would reduce HCl would also control other inorganic 
compounds that are acid gases. Thus, the best controls for HCl would 
also be the best controls for other inorganic HAP that are acid gases. 
Therefore, HCl is a good surrogate for inorganic HAP because 
controlling HCl will result in a corresponding control of other 
inorganic HAP emissions.
    For organic HAP, EPA chose to use CO as a surrogate to represent 
the variety of organic compounds, including dioxins, emitted from the 
various fuels burned in boilers and process heaters. Because CO is a 
good indicator of incomplete combustion, there is a direct correlation 
between CO emissions and the formation of organic HAP emissions. 
Monitoring equipment for CO is readily available, which is not the case 
for organic HAP. Also, it is significantly easier and less expensive to 
measure and monitor CO emissions than to measure and monitor emissions 
of each individual organic HAP. Therefore, using CO as a surrogate for 
organic HAP is a reasonable approach because minimizing CO emissions 
will result in minimizing organic HAP emissions.
    In addition to meeting emission limits, today's proposal would also 
require sources to establish control device operating parameter limits 
and continuously monitor control device operating parameters. Each 
source would establish site-specific values for the relevant parameters 
during performance tests, and use the parameter values to demonstrate 
compliance with the emission limits. We selected different operating 
parameters for each type of potential control device. The parameters 
were selected because they are good indicators of proper control device 
operation and performance, are consistent with other standards, and are 
feasible to monitor. The operating limits reasonably assure that the 
control devices continue to operate in a manner that will achieve the 
same level of control as during the performance test.


C. How Did EPA Determine the Proposed Emission Limitations for Existing 
Units?


    All standards established pursuant to section 112(d)(2) of the CAA 
must reflect MACT, the maximum degree of reduction in emissions of air 
pollutants that the Administrator, taking into consideration the cost 
of achieving such


[[Page 1672]]


emissions reductions, and any nonair quality health and environmental 
impacts and energy requirements, determined is achievable for each 
category. For existing sources, MACT cannot be less stringent than the 
average emission limitation achieved by the best performing 12 percent 
of existing sources for categories and subcategories with 30 or more 
sources. This requirement constitutes the MACT floor for existing 
boilers and process heaters. However, EPA may not consider costs or 
other impacts in determining the MACT floor. The EPA must consider 
cost, nonair quality health and environmental impacts, and energy 
requirements in connection with any standards that are more stringent 
than the MACT floor (beyond-the-floor controls).


D. How Did EPA Determine the MACT Floor for Existing Units?


    We considered several approaches to identifying MACT floor for 
existing industrial, commercial, and institutional boilers and process 
heaters. Based on recent court decisions, in most cases the most 
acceptable approach for determining the MACT floor is likely to involve 
primarily the consideration of available emissions test data. Using 
such an approach, EPA might calculate the MACT floor for a category of 
sources by ranking the emission test results from units within the 
category from lowest to highest, and then taking the numerical average 
of the test results from the best performing (lowest emitting) 12 
percent of sources.
    However, after review of the available HAP emission test data, we 
determined that it was inappropriate to use this MACT floor approach to 
establish emission limits for boilers and process heaters. The main 
problem with using only the HAP emissions data is that, based on the 
test data alone, uncontrolled units (or units with low efficiency add-
on controls) were frequently identified as being among the best 
performing 12 percent of sources in a subcategory, while many units 
with high efficiency controls were not. However, these uncontrolled or 
poorly controlled units are not truly among the best controlled units 
in the category. Rather, the emissions from these units are relatively 
low because of particular characteristics of the fuel that they burn, 
that cannot reasonably be replicated by other units in the category or 
subcategory. In fact, we expect just this kind of variability in 
emission rates given the variety of fuel types included within each 
subcategory of boilers and process heaters.
    A review of fuel analyses indicate that the concentration of HAP 
(metals, HCl, mercury) vary greatly, not only between fuel types, but 
also within each fuel type. Some fuels even have pollutant 
concentration levels below the detection limit of the applicable 
analytical test method. Therefore, a unit without any add-on controls, 
but burning a fuel containing lower amounts of HAP, can have emission 
levels that are lower than the emissions from a unit with the best 
available add-on controls. If only the available HAP emissions data are 
used, the resulting MACT floor levels would be unachievable for many 
existing units, even those that employ the most effective available 
emission control technology. For example, an uncontrolled boiler 
burning wood may have lower emissions of mercury than a well controlled 
boiler burning coal. In fact, coal burning boilers may never be able to 
achieve the mercury HAP level of the wood-fired unit, no matter what 
add-on controls are used. In this instance, establishing a MACT 
standard based on emission data alone would force the coal units to 
switch to different fuels to achieve the MACT limits. As discussed 
later in this section, fuel switching is not an appropriate or 
available control option for identifying the MACT floors for boilers 
and process heaters.
    Another problem with using only emissions data is that there is no 
HAP emissions information available to the Agency for some of the 
subcategories. This is consistent with the fact that units in these 
source categories have not historically been required to test for HAP 
emissions.
    We also considered using HAP emission limits contained in State 
regulations and permits as a surrogate for actual emission data in 
order to identify the emissions levels from the best performing units 
in the category for purposes of establishing MACT standards. However, 
we found no State regulations or State permits that specifically limit 
HAP emissions from these sources.
    Consequently, we concluded that the most appropriate approach for 
determining MACT floors for boilers and process heaters was to look at 
the control options used by the units within each subcategory in order 
to identify the best performing units. Information was available 
regarding the emission control options employed by the population of 
boilers identified by the EPA. We considered several possible control 
controls (i.e., factors that influence emissions), including fuel 
substitution, process changes and work practices, and add-on control 
technologies.
    We considered first whether fuel switching would be an appropriate 
control option for sources in each subcategory. We considered the 
feasibility of fuel switching to other fuels used in the subcategory 
and to fuels from other subcategories. This consideration included 
determining whether switching fuels would achieve lower HAP emissions. 
A second consideration was whether fuel switching could be technically 
achieved by boilers and process heaters in the subcategory considering 
the existing design of boilers and process heaters. We also considered 
the availability of various types of fuel.
    After considering these factors, we determined that fuel switching 
was not an appropriate control technology for purposes of determining 
the MACT floor level of control for any subcategory. This decision was 
based on the overall effect of fuel switching on HAP emissions, 
technical and design considerations discussed previously in this 
preamble, and concerns about fuel availability.
    Based on the data available in the emissions database, we 
determined that while fuel switching from solid fuels to gaseous or 
liquid fuels would decrease PM and some metals emissions, emissions of 
some organic HAP would increase, resulting in uncertain benefits. This 
determination is discussed in the memorandum ``Development of Fuel 
Switching Costs and Emission Reductions for Industrial, Commercial, and 
Institutional Boilers and Process Heaters National Emission Standards 
for Hazardous Air Pollutants'' located in the docket. We believe that 
it is inappropriate in a MACT rulemaking to consider as MACT a control 
option that potentially will decrease emissions of one HAP while 
increasing emissions of another HAP. In order to adopt such a strategy, 
EPA would need to assess the relative risk associated with each HAP 
emitted, and determine whether requiring the control in question would 
result in overall lower risk. Such an analysis is not appropriate at 
this stage in the regulatory process.
    A similar determination was made when considering fuel switching to 
cleaner fuels within a subcategory. For example, the term ``clean 
coal'' refers to coal that is lower in sulfur content and not 
necessarily lower in HAP content. Data gathered by EPA also indicates 
that within specific coal types HAP content can vary significantly. 
Switching to a low sulfur coal may actually increase emissions of some 
HAP. Therefore, it is not appropriate for EPA to include fuel switching 
to a low sulfur coal as part of the MACT standards for boilers and 
process heaters. Fuel switching from coal to biomass would result in 
similar


[[Page 1673]]


impacts on HAP emissions. While this would reduce metallic HAP 
emissions, it would likely increase emissions of organics based on 
information in the emissions database.
    Another factor considered was the availability of alternative fuel 
types. Natural gas pipelines are not available in all regions of the 
U.S., and natural gas is simply not available as a fuel for many 
industrial, commercial, and institutional boilers and process heaters. 
Moreover, even where pipelines provide access to natural gas, supplies 
of natural gas may not be adequate. For example, it is common practice 
in cities during winter months (or periods of peak demand) to 
prioritize natural gas usage for residential areas before industrial 
usage. Requiring EPA regulated combustion units to switch to natural 
gas would place an even greater strain on natural gas resources. 
Consequently, even where pipelines exist, some units would not be able 
to run at normal or full capacity during these times if shortages were 
to occur. Therefore, under any circumstances, there would be some units 
that could not comply with a requirement to switch to natural gas.
    Similar problems for fuel switching to biomass could arise. 
Existing sources burning biomass generally are combusting a recovered 
material from the manufacturing or agriculture process. Industrial, 
commercial, and institutional facilities that are not associated with 
the wood products industry or agriculture may not have access to a 
sufficient supply of biomass materials to replace their fossil fuel.
    As discussed previously in this preamble, there is a significant 
concern that switching fuels would be infeasible for sources designed 
and operated to burn specific fuel types. Changes in the type of fuel 
burned by a boiler or process heater (solid, liquid, or gas) may 
require extensive changes to the fuel handling and feeding system 
(e.g., a stoker using wood as fuel would need to be redesigned to 
handle fuel oil or gaseous fuel). Additionally, burners and combustion 
chamber designs are generally not capable of handling different fuel 
types, and generally cannot accommodate increases or decreases in the 
fuel volume and shape. Design changes to allow different fuel use, in 
some cases, may reduce the capacity and efficiency of the boiler or 
process heater. Reduced efficiency may result in less complete 
combustion and, thus, an increase in organic HAP emissions. For the 
reasons discussed above, we decided that fuel switching to cleaner 
solid fuels or to liquid or gaseous fuels is not an appropriate 
criteria for identifying the MACT floor level of control for units in 
the boilers and process heaters category.
    We also concluded that process changes or work practices were not 
appropriate criteria for identifying the MACT floor level of control 
for units in the boilers and process heaters category. The HAP 
emissions from boilers and process heaters are primarily dependent upon 
the composition of the fuel. Fuel dependent HAP are metals, including 
mercury, and acid gases. Fuel dependent HAP are typically controlled by 
removing them from the flue gas after combustion. Therefore, they are 
not affected by the operation of the boiler or process heater. 
Consequently, process changes would be ineffective in reducing these 
fuel-related HAP emissions.
    On the other hand, organic HAP can be formed from incomplete 
combustion of the fuel. Combustion is defined as the rapid chemical 
combination of oxygen with the combustible elements of a fuel. The 
objective of good combustion is to release all the energy in the fuel 
while minimizing losses from combustion imperfections and excess air. 
The combination of the fuel with the oxygen requires temperature (high 
enough to ignite the fuel constituents), mixing or turbulence (to 
provide intimate oxygen-fuel contact), and sufficient time (to complete 
the process), sometimes referred to the three Ts of combustion. Good 
combustion practice (GCP), in terms of boilers and process heaters, 
could be defined as the system design and work practices expected to 
minimize organic HAP emissions. The GCP control strategy could include 
a number of combustion conditions and work practices which are applied 
collectively to achieve this goal.
    While few sources in EPA's database specifically reported using 
good combustion practices, the data that we have suggests that boilers 
and process heaters within each subcategory might use any of a wide 
variety of different work practices, depending on the characteristics 
of the individual unit. The lack of information, and lack of a uniform 
approach to assuring combustion efficiency, is not surprising given the 
extreme diversity of boilers and process heaters, and given the fact 
that no applicable Federal standards, and most applicable State 
standards, do not include work practice requirements for boilers and 
process heaters. Even those States that do have such requirements do 
not require the same work practices. For example, CO emissions are 
generally a good indicator of incomplete combustion, and, therefore, 
low CO emissions might reflect good combustion practices. Therefore, we 
considered whether existing CO monitoring requirements and emission 
limits might be used to establish good combustion practice standards 
for boilers and process heaters. (As discussed previously in this 
preamble, CO is also a surrogate for organic HAP emissions in the 
proposed rule.) The population databases did not contain information 
regarding whether existing units monitored CO emissions. Therefore, we 
reviewed State regulations applicable to boilers and process heaters, 
and then for each subcategory we matched the applicability of State CO 
monitoring requirements or emission limits with information on the 
locations and characteristics of the boilers and process heaters in the 
population database. Ultimately, we found that very few units (less 
than 6 percent) in any subcategory were subject to CO monitoring 
requirements or emission limits. We concluded that this information did 
not allow EPA to identify a level of performance that was 
representative of good combustion across the various units in any 
subcategory.
    Consequently, EPA was unable to identify any uniform requirements 
or set of work practices that would meaningfully reflect the use of 
good combustion practices, or that could be meaningfully implemented 
across any subcategory of boilers and process heaters. Therefore, EPA 
is not establishing combustion practice requirements as a part of the 
MACT floor for existing units. However, we have considered the 
appropriateness of such requirements in the context of evaluation 
possible beyond-the-floor options.
    In general, boilers and process heaters are designed for good 
combustion. Facilities have an economic incentive to ensure that fuel 
is not wasted, and the combustion device operates properly and is 
appropriately maintained. In fact, existing boilers and process heaters 
are used typically as high efficiency control devices to control 
(reduce) emission streams containing organic compounds from various 
process operations. Therefore, EPA's inability to establish a 
combustion practice requirement as part of the MACT floor for existing 
sources in this category should not reduce the incentive for owners and 
operators to run their boilers and process heaters at top efficiency.
    We request comment, and emissions information, regarding whether 
there are any uniform GCP practices that would be appropriate for 
minimizing organic HAP emissions from any subcategory of


[[Page 1674]]


industrial, commercial, and institutional boilers and process heaters.
    As a result of the preceding evaluation of the feasibility of 
establishing emission limits based on control techniques such as fuel 
switching and good combustion practices, we concluded that add-on 
control technology should be the primary factor for purposes of 
identifying the best controlled units within each subcategory of 
boilers and process heaters. In order to determine the MACT floor based 
primarily on add-on control technologies, we first examined the 
population database of existing sources. Units not meeting the 
definition of an industrial, commercial, or institutional boiler or 
process heater, and units located at area sources were removed from the 
database. The remaining units were divided first into three 
subcategories based on fuel state: gaseous fuel-fired, liquid fuel-
fired, and solid fuel-fired units. Each of these three subcategories 
was then further divided into subcategories based on capacity: (1) 
Large units (watertube boilers and process heaters with heat inputs 
greater than 10 MMBtu/hr); (2) small units (firetube boilers and any 
boiler and process heater with a maximum rated heat input capacity of 
10 MMBtu/hr or less); and (3) limited use units with capacity 
utilization less than 10 percent.
    We identified the types of air pollution control techniques 
currently used by existing boilers and process heaters in each 
subcategory. We ranked those controls according to their effectiveness 
in removing the different categories of pollutants; including metallic 
HAP and PM, inorganic HAP such as acid gases, mercury, and organic HAP. 
The EPA ranked these existing control technologies by incorporating 
recommendations made by the ICCR, and by reviewing emissions test data, 
previous EPA studies, and other literature, as well as by using 
engineering judgement.
    Based upon the emissions reduction potential of existing air 
pollution control techniques, we listed all the boilers and process 
heaters in the population database in order of decreasing control 
device effectiveness within each subcategory for each pollutant type. 
Then we identified the top 12 percent of units within each category 
based on this ranking, and determined what kind of emission control 
technology, or combination of technologies, the units in the top 12 
percent employed. Finally, we looked at the emissions test data from 
boilers and process heaters that used the same control technology, or 
technologies, as the units in the top 12 percent to estimate the 
average emissions limitation achieved by these units.
    The last part in the process described above, involving the 
calculation of numerical emission limits, was a two-step analysis. The 
first step involved calculating a numerical average of an appropriate 
subset of the emission test data from units using the same technology, 
or technologies, as the units in the top 12 percent. Based on the 
initial ranking, we determined what proportion of the units using a 
particular technology were among the top 12 percent of units in the 
subcategory. Then we looked at a corresponding proportion of the 
emission test data from units using that type of control technology, 
and produced an overall average measured performance level. For 
example, in the large solid-fuel subcategory, approximately 14 percent 
of units used the best performing control technology for PM/metallic 
HAP (baghouses). In order to rank the units using the best technology 
for which we had emission test data, we generated unit by unit measured 
performance levels by averaging the multiple tests from each individual 
unit (if multiple tests were available). Then we looked at the best 12/
14 of the units for which we generated such individual averages, and 
averaged the unit by unit averages from all of these units. This 
resulted in an overall average measured emissions performance level for 
units representative of the top 12 percent of units in the subcategory.
    The second step in this part of the process involved generating and 
applying an appropriate variability factor to account for unavoidable 
variations in emissions due primarily to uncontrollable differences in 
fuel characteristics and ordinary operational variability. First, we 
identified all the units for which we had emission test data using the 
same technology, or technologies, as units in the top 12 percent. Then, 
for each such unit with multiple emission tests, we calculated the 
variability in the measured emissions from that unit by dividing the 
highest three-run test result by the lowest three-run test result. 
Finally, we calculated the overall variability in the measured 
emissions from these units by averaging all the individual unit 
variability factors, and we applied this overall variability factor to 
the overall average measured emissions performance level (as described 
above) to derive a emission limit representative of the average 
emission limitation achieved by the top 12 percent of units.
    This approach reasonably ensures that the emission limit selected 
as the MACT floor adequately represents the average level of control 
actually achieved by units in the top 12 percent, considering ordinary 
operational variability. Both the analysis of the measured emissions 
from units representative of the top 12 percent, and the variability 
analysis, are reasonably designed to provide a meaningful estimate of 
the average performance, or central tendency, of the best controlled 12 
percent of units in a given subcategory. Using such an approach, 
including a variability factor, is reasonable because the estimated 
performance of the best controlled units must account for variability 
in the performance of the units over time and under different 
operational conditions. Absent comprehensive emission data, there is no 
reason to believe that any individual unit could consistently achieve 
the emission performance demonstrated by a limited set of emission 
tests. Because, each emission test is but a snapshot of actual and 
ongoing performance, taken at one moment in time, evaluating the 
snapshots collectively is the best way to estimate the unavoidable 
variation in emissions expected to occur and recur over time at 
similarly controlled units in the category (or subcategory). As a 
result, the most reasonable methodology for determining the variability 
among the best controlled units is to evaluate the overall variability 
in the performance of the particular control technology that those 
units use, by examining the variability among the emission test results 
(the performance snapshots) for all similarly controlled units 
(excluding any emission values from tests that did not represent a 
proper functioning system). Accordingly, we have used the available 
emissions data to reasonably estimate the variability of the top 
performing units in each subcategory.
    The EPA's review of emissions data indicates that some boilers and 
process heaters within each subcategory may be able to meet the floor 
emission levels without using the air pollution control technology that 
is used by the top 12 percent of units in the subcategory. This is to 
be expected given the variety of fuel types, fuel input rates, and 
boiler designs included within each subcategory and the resulting 
variability in emission rates. Thus, for instance, boilers or process 
heaters within the large unit solid fuel subcategory that burn lower 
percentages of solid fuels may be able to achieve the emission levels 
for the large unit solid fuel subcategory without the need for 
additional control devices.
    Furthermore, solid fuels, especially coal, are very heterogeneous 
and can


[[Page 1675]]


vary in composition by location. Coal analysis data obtained from the 
electric utility industry in another rulemaking contained information 
on the mercury, chlorine, and ash content of various coals. A 
preliminary review of this data indicate that the composition can vary 
greatly from location to location, and also within a particular 
location. Based on the range of variation of mercury, chlorine, and ash 
content in coal, it is possible for a unit with a lower performing 
control system to have emission levels lower than a unit considered to 
be included in the best performing 12 percent of the units.
    This situation is reflected in the emissions information used to 
set the MACT floor emission limits. In some instances there are boilers 
with ESP or other controls that achieve similar, or lower, outlet 
emission levels of non-mercury metallic HAP, PM, or mercury than fabric 
filters. In most cases, this is due to concentrations entering these 
other control devices being lower, even though the percent reduction 
achieved is lower than fabric filters.
    Additionally, the design of some control devices may have a 
substantial effect on their emissions reductions capability. For 
example, fabric filters are largely insensitive to the physical 
characteristics of the inlet gas stream. Thus, their design does not 
vary widely, and emissions reductions are expected to be similar (e.g. 
99 percent reduction of PM). However, ESP design can vary 
significantly. Some ESP are two fields, others may have three or four. 
The more fields the larger the emissions reductions for PM. Similarly, 
other devices can be designed to achieve higher emissions reductions. 
This level of detail was not available for the information used to 
develop the MACT floor emission limits.
    Consequently, since fuel substitution has been determined not to be 
an appropriate MACT floor control technology, EPA still considers the 
fabric filter to be the best performing control for non-mercury 
metallic HAP, PM, and mercury and only emissions information for fabric 
filters was used to develop emission limits.
    For existing unit subcategories where less than 12 percent of units 
in the subcategory use any type of control technology, we could not use 
the same approach to identify the average level of control achieved by 
the top 12 percent. Therefore, we looked to see if we could estimate 
the central tendency of the best controlled units by looking at the 
median unit of the top 12 percent (the unit at the 94th percentile). 
Under such circumstances, if the median unit of the top 12 percent is 
using some control technology, we might use the measured emission 
performance of that individual unit as the basis for estimating an 
appropriate average level of control of the top 12 percent. For 
subcategories where even the median unit is using no control 
technology, the average control of the top 12 percent of units is no 
emissions reductions.
    A detailed discussion of the MACT floor methodology is presented in 
the memorandum ``MACT Floor Analysis for the Industrial, Commercial, 
and Institutional Boilers and Process Heaters National Emission 
Standards for Hazardous Air Pollutants'' in the docket.
1. Existing Solid Fuel Boilers and Process Heaters
    a. Large Units--Heat Inputs Greater than 10 MMBtu/hr. The most 
effective control technologies identified for removing non-mercury 
metallic HAP and PM are fabric filters. About 14 percent of solid fuel-
fired boilers and process heaters use fabric filters. Because greater 
than 12 percent of units in the category use this technology, and 
because there are no options reasonably available for reducing HAP 
emissions other than add-on control, we consider sources with fabric 
filters to be the best controlled sources in this subcategory for 
purposes of metallic HAP and PM emissions. Thus, it is appropriate to 
use the measured performance of sources with fabric filters as the 
basis for establishing the MACT floor for non-mercury metallic HAP and 
PM for existing boilers and process heaters in this subcategory.
    As described earlier, a PM level is set as a surrogate for non-
mercury metallic HAP. The MACT floor emission level based on PM test 
data from the solid fuel units with fabric filters representing the top 
12 percent, and incorporating operational variability (using results 
from multiple tests on best performing units), is 0.07 lb PM/MMBtu. We 
are also providing an alternative metals limit of 0.001 lb metals/MMBtu 
which can be used to show compliance in cases where metal HAP emissions 
are low in proportion to PM emissions. This is because, according to 
the emissions database, some biomass units have low metals content but 
high PM emissions. The emission level for metals was selected from 
metals test data associated with PM emission tests from fabric filters 
that met the MACT floor PM emission level.
    The most effective control technologies identified for removing 
inorganic HAP that are acid gases, such as HCl, are wet scrubbers and 
packed bed scrubbers. These technologies are used by about 13 percent 
of the boilers and process heaters in the large solid fuel subcategory. 
About 12 percent of solid fuel-fired boilers and process heaters use 
wet or dry scrubbers, and approximately 1 percent use packed bed 
scrubbers.
    Because greater than 12 percent of units in the category use this 
technology, and because there are no options reasonably available for 
reducing HAP emission other than add-on control, we consider sources 
with wet or dry scrubbers and packed bed scrubbers to be the best 
controlled sources in this subcategory for purposes of inorganic HAP 
emissions. Thus, it is appropriate to use the measured performance of 
sources with wet or dry scrubbers and packed bed scrubbers as the basis 
for establishing the MACT floor for inorganic HAP for existing boilers 
and process heaters in this subcategory. The MACT floor emission level 
based on HCl emissions test data from units using wet or dry scrubbers 
and packed bed scrubbers representing the top 12 percent, and 
incorporating operational variability, is 0.09 lb HCl/MMBtu.
    Based on test information on utility boilers, we have concluded 
that fabric filters are the most effective technology for controlling 
mercury emissions. As discussed previously, approximately 14 percent of 
sources in the subcategory use fabric filters. The MACT floor emission 
level for mercury, based on the measured performance of units with 
fabric filters representing the top 12 percent, and incorporating 
operational variability, is 0.000007 lb mercury/MMBtu.
    Although EPA used information from utility boilers to conclude that 
fabric filters are the most effective control technology for 
controlling mercury emissions, this same information suggests that 
different fuel characteristics (e.g. mercury and chlorine content of 
the fuel burned) can lead to both different outlet mercury (Hg) 
concentrations and different control efficiencies for equivalent 
control devices.\1\ We have emissions test results for mercury 
emissions from seven industrial boilers and process heaters equipped 
with fabric filters. The Agency has information about the general type 
of fuel being burned during


[[Page 1676]]


the emission tests, such as coal, wood, or some mixture of fuel types. 
However, we have no detailed information about the specific 
characteristics (such as mercury or chlorine content) of the fuel being 
burned during those emissions tests. Nonetheless, we believe that the 
use of variability factors adequately accounts for potential variations 
in fuel mercury and chloride content.
---------------------------------------------------------------------------


    \1\ The speciation of mercury in the flue gas is believed to 
affect the amount of mercury captured by control devices. Mercury 
can be present in both vapor form (as insoluble elemental mercury 
and as soluble oxidized mercury (such as, mercury chloride)) and in 
particulate form. The capture of elemental mercury is reportedly 
more difficult than the capture of oxidized mercury or mercury in 
particulate form.
---------------------------------------------------------------------------


    However, because we have very limited data on actual emissions from 
industrial boilers and process heaters, the Agency is soliciting 
comment on whether the variability analysis in the current proposal 
adequately addresses the impact that fuel characteristics (such as 
mercury and chlorine content) can have on mercury emissions from a 
source equipped with fabric filters. As discussed earlier, the Agency 
is not currently considering fuel switching as a control option in 
setting the MACT floor. Therefore, the Agency requests specific 
information regarding both the mercury and chlorine content 
characteristics of the fuel used in, and the mercury emissions from, 
industrial boilers and process heaters equipped with well designed and 
operated fabric filters.
    Comments on this issue should include specific data regarding both 
the characteristics of the fuel burned (including mercury and chlorine 
content along with any other pertinent characteristics) and current 
mercury emissions of these industrial boilers and process heaters.
    For organic HAP, we attempted to determine the level of control 
being achieved by the top 12 percent of units within the subcategory, 
however, less than 6 percent of the units in this subcategory use any 
type of organic HAP control (by limiting CO emissions). Thus, while a 
small proportion of units in the subcategory monitor and control their 
CO emissions (and, therefore, limit emissions of organic HAP), the 
majority of units in the subcategory (and in the top 12 percent) do not 
control these emissions. Because so few units control emissions of 
organic HAP, we could not calculate an average limitation achieved by 
the top 12 percent as we did for metallic HAP/PM, inorganic HAP/HCl, 
and mercury. We looked then at whether the median unit of the top 12 
percent might provide some indication of the central tendency of the 
top 12 percent. However, because fewer than 6 percent of units are 
controlled, the median unit reflects no emissions reductions for 
organic HAP. Therefore, we concluded that the MACT floor for existing 
sources in this subcategory is no emissions reductions for organic HAP.
    Consequently, EPA determined that, in general, the combination of 
fabric filter and wet scrubber control technologies forms the basis for 
the MACT floor level of control for existing large solid fuel boilers 
or process heaters. We recognize that some boilers and process heaters 
that use technologies other than those used as the basis of the MACT 
floor can achieve the MACT floor emission levels. For example, emission 
test data show that many boilers with well designed and operated ESP 
can meet the MACT floor emission levels for non-mercury metallic HAP 
and PM, even though the floor emission level for these pollutants is 
based on units using a fabric filters (however, we would not expect 
that all units using ESP would be able to meet the emission limits in 
the proposed rule).
    b. Small Units--Heat Inputs Less than or Equal to 10 MMBtu/hr. For 
each pollutant group (non-mercury metallic HAP and PM, mercury, 
inorganic HAP/HCl, and organic HAP), less than 6 percent of the units 
in this subcategory used control techniques that limit emissions. 
Because so few units in the subcategory control emissions of HAP, we 
could not calculate an average limitation achieved by the top 12 
percent for any HAP grouping. We looked then at whether the median unit 
of the top 12 percent might provide some indication of the central 
tendency of the top 12 percent for any HAP grouping. However, because 
fewer than 6 percent of units in each HAP grouping used controls or 
limited emissions, the median unit for each HAP grouping reflects no 
emissions reduction.
    Therefore, we determined that the MACT floor emission level for 
existing units for each of the pollutant categories in this subcategory 
is no emissions reductions.
    c. Limited Use Units--Capacity Utilizations Less than or Equal to 
10 Percent. The most effective control technologies identified for 
removing non-mercury metallic HAP and PM are ESP and fabric filters. 
Less than 2 percent of limited use solid fuel-fired boilers and process 
heaters use fabric filters, and 14 percent use ESP. Therefore, we used 
the measured performance of units using ESP and fabric filters as the 
basis for the MACT floor for non-mercury metallic HAP and PM. We 
established a PM level as a surrogate for non-mercury metallic HAP 
control, reflecting the emission test data from units using ESP and 
fabric filters that were representative of the top 12 percent of units 
in the subcategory.
    The emissions test database did not contain test data for limited 
use boilers and process heaters. In order to develop emission levels 
for this subcategory, we decided to use information from units in the 
large solid fuel subcategory. We considered this to be an appropriate 
methodology because although the units in this subcategory are 
different enough to warrant their own subcategory (i.e., different 
purposes and operation), emissions of the specific types of HAP for 
which limits are being proposed (HCl and non-mercury metals) are 
expected to be related more to the type of fuel burned and the type of 
control used, than to unit operation. Consequently, we determined that 
emissions information from the large solid fuel subcategory could be 
used to establish MACT floor levels for this subcategory because the 
fuels and controls are similar. The MACT floor emission level based on 
this test data, considering operational variability, is 0.02 lb PM/
MMBtu. We are also providing an alternative metals limit of 0.001 lb 
metals/MMBtu which can be used to show compliance in cases where metal 
HAP emissions are low in proportion to PM emissions. The emissions 
database indicates that some biomass units have low metals content but 
high PM emissions. The emission level for metals was selected from 
metals test data associated with PM emission tests from fabric filters 
that met the MACT floor PM emission level.
    Similar control technology analyses were done for the boilers and 
process heaters in this subcategory for the other pollutant groups of 
interest, including inorganic HAP, organic HAP and mercury. For each of 
these pollutant groups, less than 6 percent of the units in this 
subcategory used control techniques that limit emissions. Because so 
few units in the subcategory control emissions of these HAP, we could 
not calculate an average limitation achieved by the top 12 percent for 
inorganic HAP, organic HAP and mercury. We looked then at whether the 
median unit of the top 12 percent might provide some indication of the 
central tendency of the top 12 percent for any of these HAP groupings. 
However, because fewer than 6 percent of units in each HAP grouping 
used controls or limited emissions, the median unit for each HAP 
grouping reflects no emission reductions. Therefore, we concluded that 
the MACT floor for inorganic HAP, organic HAP and mercury in this 
subcategory is no emissions reductions. Consequently, we determined 
that ESP and fabric filters, which achieve non-mercury metallic HAP and 
PM control, form the basis for the MACT floor level of control for


[[Page 1677]]


existing solid fuel boilers and process heaters in this subcategory.
2. Existing Liquid Fuel Boilers and Process Heaters
    Emission data for liquid subcategories were inadequate to identify 
the best performing sources for reasons described previously in this 
preamble. We also found no State regulations or permits which 
specifically limit HAP emissions from these sources. Therefore, we 
examined control technology information to identify a MACT floor. We 
found that less than 6 percent of the units in each of the liquid 
subcategories used control techniques that would reduce non-mercury 
metallic HAP and PM, mercury, organic HAP, or acid gases, (such as 
HCl). Therefore, we concluded, for each subcategory of liquid fueled 
boilers and process heaters, that the MACT floor is no emission 
reductions for non-mercury metallic HAP, mercury, inorganic HAP, and 
organic HAP.
3. Existing Gaseous Fuel Boilers and Process Heaters
    Emission data for gas subcategories were inadequate to identify the 
best performing sources for reasons described in section III.D of this 
preamble. We also found no State regulations or permits that 
specifically limit HAP emissions from these sources. Therefore, we 
examined control technology information to identify a MACT floor. We 
found that no existing units in the gaseous fuel-fired subcategories 
were using control technologies that achieve consistently lower 
emission rates than uncontrolled sources for any of the pollutant 
groups of interest. Therefore, we are unable to identify the best 
performing 12 percent of units in the subcategories. Consequently, EPA 
determined that no existing source MACT floor based on control 
technologies could be identified for gaseous fuel-fired units. 
Therefore, we concluded the MACT floor for existing sources in this 
subcategory is no emissions reductions for non-mercury metallic HAP, 
mercury, inorganic HAP, and organic HAP.


E. How Did EPA Consider Beyond-the-Floor Options for Existing Units?


    Once the MACT floor determinations were done for each subcategory, 
EPA considered various regulatory options more stringent than the MACT 
floor level of control (i.e., technologies or other work practices that 
could result in lower emissions) for the different subcategories.
    Maintaining and monitoring CO levels was identified as a possible 
control for organic HAP. In addition to looking at whether CO limits 
should be a part of the MACT floor, we looked at this option as a 
beyond-the-floor option. However, information was not available to 
estimate the HAP emissions reductions that would be associated with CO 
monitoring and emission limits. This option would also require a high 
cost to install and operate CO monitors. Given the cost and the 
uncertain emissions reductions that might be achieved, we chose to not 
require CO monitoring and emission limits as MACT.
    The following sections discuss the beyond-the-floor options 
analyzed to control emissions of metallic HAP, mercury, and inorganic 
HAP. Based on the analysis in these sections, EPA decided to not go 
beyond the MACT floor level of control for the proposed rule for any of 
the subcategories of existing sources. A detailed description of the 
beyond-the-floor consideration is in the memorandum ``Methodology for 
Estimating Cost and Emissions Impacts for Industrial, Commercial, 
Institutional Boilers and Process Heaters National Emission Standards 
for Hazardous Air Pollutants'' in the docket.
1. Existing Solid Fuel Units
    a. Large Units--Heat Inputs Greater than 10 MMBtu/hr. Besides fuel 
switching, we identified a better designed and operated fabric filter 
(the MACT floor for new units) as a control technology that could 
achieve greater emissions reductions of metallic HAP and PM emissions 
than the MACT floor level of control. Consequently, EPA analyzed the 
emissions reductions and additional cost of adopting an emission limit 
representative of the performance of a unit with a better designed and 
operated fabric filter. The additional annualized cost to comply with 
this emission limit was estimated to be approximately 500 million 
dollars with an additional emission reduction of approximately 100 tons 
of metallic HAP. The results indicated that while additional emissions 
reductions would be realized, the costs would be too high to consider 
it a feasible beyond-the-floor option. Nonair quality health, 
environmental impacts, and energy effects were not significant factors, 
because there would be little difference in the nonair quality health 
and environmental impacts of replacing existing fabric filters with 
improved performance fabric filters. Therefore, we did not select these 
controls as MACT. Fuel switching was not considered a feasible beyond-
the-floor option for the same reasons described previously in this 
preamble.
    We identified packed bed scrubbers as a control technology that 
could achieve greater emissions reductions of inorganic HAP, like HCl, 
than the MACT floor level of control. Consequently, EPA analyzed the 
emissions reductions and additional cost of adopting an emission limit 
representative of the performance of a unit with a packed bed scrubber. 
The additional annualized cost to comply with this emission limit 
(using a packed bed scrubber) was estimated to be approximately 900 
million dollars with an additional emission reduction of approximately 
20,000 tons of HCl. The results indicated that while additional 
emissions reductions would be realized, the costs would be too high to 
consider it a feasible beyond-the-floor option. Nonair quality health, 
environmental impacts, and energy effects were not significant factors, 
because there would be little difference in the nonair quality health 
and environmental impacts between packed bed scrubbers and the 
technology that is likely to be used to meet the MACT floor level of 
control. Therefore, we did not select these controls as MACT.
    In reviewing potential regulatory options for existing sources, EPA 
identified one existing industrial boiler that was using a technology, 
carbon injection, used in other industries to achieve greater control 
of mercury emissions than the MACT floor level of control. However, 
emission data indicated that this unit was not achieving mercury 
emission reduction. The EPA does not have information that would show 
carbon injection is effective for reducing mercury emissions from 
industrial, commercial, and institutional boilers and process heaters. 
Therefore, carbon injection was not evaluated as a regulatory options.
    However, EPA requests comments on whether carbon injection should 
be considered as a beyond-the-floor option and whether existing 
industrial, commercial, or institutional boilers and process heaters 
could use carbon injection technology, or other control techniques to 
consistently achieve mercury emission levels that are lower than levels 
from similar sources with the MACT floor level of control. Comments 
should include information on emissions, current demonstrated 
applications, and costs, including retrofit costs. The EPA is aware 
that research continues on ways to improve mercury capture by PM 
controls, sorbent injection, and the development of novel techniques. 
The EPA requests comment and information on the effectiveness of such 
control


[[Page 1678]]


technologies in reducing mercury emissions.
    b. Small Units--Heat Inputs Less than or Equal to 10 MMBtu/hr. The 
MACT floor for this subcategory is no emission reductions. To control 
non-mercury metallic HAP and mercury, we analyzed the beyond-the-floor 
option of a fabric filter which was identified, generally, as the most 
effective control device for non-mercury metallic HAP and mercury. To 
control inorganic HAP such as HCl, we analyzed the beyond-the-floor 
option of a wet scrubber since it was identified as the least cost 
option.
    The total annualized cost of complying with the fabric filter 
option was estimated to be 10 million dollars, with an estimated 
emission reduction of 1.9 tons per year of non-mercury metallic HAP and 
0.003 tons of mercury. The annualized cost of complying with the wet 
scrubber option was estimated to be 11 million dollars, with an 
emission reduction of 48 tons per year of HCl. The results of this 
analysis indicated that while additional emissions reductions could be 
realized, the costs would be too high to consider them feasible 
options. Therefore, we did not select these controls as MACT. Nonair 
quality health, environmental impacts, and energy effects were not 
significant factors.
    c. Limited Use Units--Capacity Utilizations Less than or Equal to 
10 Percent. The MACT floor level for this subcategory for non-mercury 
metallic HAP control is 0.2 lb PM/MMBtu (this level of control can 
generally be achieved by using an ESP or fabric filter). Although 
fabric filters were identified as being more effective, many ESP can 
achieve similar levels. Any additional emission reduction from using a 
fabric filter would be minimal and costly considering retrofit costs 
for existing units that already have ESP. Therefore, a beyond-the-floor 
option for metallic HAP was not analyzed in detail. However, a beyond-
the-floor option based on the level of performance of a fabric filter 
was analyzed for mercury control. The total annualized costs of the 
fabric filter option was estimated to be an additional 21 million 
dollars, with an estimated emission reduction of 0.04 tons of mercury.
    The MACT floor for inorganic HAP in this subcategory was no 
emission reductions. For beyond-the-floor control of inorganic HAP, we 
analyzed the level of performance generally achievable by a wet 
scrubber since it was identified as the least cost option. The total 
annualized costs of the wet scrubber option was estimated to be 49 
million dollars, with an estimated emission reduction of 463 tons per 
year of HCl.
    The results of the beyond-the-floor analyses indicated that while 
additional emissions reductions could be realized, the costs would be 
too high to consider them feasible options. Therefore, we did not 
select these controls as MACT. Nonair quality health, environmental 
impacts, and energy effects were not significant factors.
2. Existing Liquid Fuel Units
    The MACT floor for each liquid fuel subcategory is no emission 
reductions. For beyond-the-floor options for the liquid subcategory, 
EPA identified several PM controls (e.g., fabric filters, ESP, and 
venturi scrubbers) that would reduce non-mercury metallic HAP 
emissions. For the beyond-the-floor analysis, we analyzed the cost and 
emission reduction of applying a high efficiency PM control device, 
such as a fabric filter, since these would be more likely to be 
installed for units firing liquid fuel. We identified wet scrubbers as 
a technology beyond-the-floor option for reduction of inorganic HAP, 
such as HCl. We identified fabric filters as a beyond-the-floor 
technology option for reduction of mercury. Consequently, EPA analyzed 
the emissions reductions and additional cost of applying high 
efficiency PM controls and wet scrubbers on liquid fuel-fired units. 
The additional total annualized cost of a high efficiency PM control 
device (such as a fabric filter) was estimated to be 460 million 
dollars, with an additional estimated emission reduction of 1,500 tons 
per year for non-mercury metallic HAP and 3 tons per year for mercury. 
The annualized cost of a wet scrubbers was estimated to be an 
additional 480 million dollars, with an additional HCl reduction of 30 
tons per year. The results indicated that while additional emissions 
reductions would be realized, the costs would be too high to consider 
them feasible options. Nonair quality health, environmental impacts, 
and energy effects were not significant factors. Therefore, EPA chose 
to not select these controls as MACT for existing liquid units.
3. Existing Gas-Fired Units
    The MACT floor for each gaseous fuel subcategory is no emission 
reductions. The great majority, if not all, of the emissions from gas-
fired units are organic HAP. As discussed previously in this preamble, 
CO monitoring and emission limits were considered as a beyond-the-floor 
option, but were not selected as MACT given the costs and uncertain HAP 
reductions achieved. Therefore, no beyond-the-floor control technique 
was analyzed for organic HAP, and MACT is no emission reduction of non-
mercury metallic HAP, mercury, inorganic HAP, and organic HAP.
4. Fuel Switching as a Beyond-the-Floor Option
    For the solid fuel and liquid fuel subcategories, fuel switching to 
natural gas is a regulatory option more stringent than the MACT floor 
level of control that would reduce mercury, metallic HAP, and inorganic 
HAP emissions. We determined that fuel switching was not an appropriate 
beyond-the-floor option for the reasons discussed previously in this 
preamble. For example, natural gas supplies are not available in some 
areas, and supplies to industrial customers can be limited during 
periods when natural gas demand exceeds supply. Furthermore, in some 
cases, organic HAP would be increased by fuel switching. Additionally, 
the estimated emissions reductions that would be achieved if solid and 
liquid fuel units switched to natural gas were compared with the 
estimated cost of converting existing solid fuel and liquid fuel units 
to fire natural gas. The annualized cost of fuel switching was 
estimated to be $12 billion. The additional emission reduction 
associated with fuel switching was estimated to be 1,500 tons per year 
for metallic HAP, 11 tons per year for mercury, and 13,000 tons per 
year for inorganic HAP. Additional detail on the calculation procedures 
is provided in the memorandum ``Development of Fuel Switching Costs and 
Emissions Reductions for Industrial, Commercial, and Institutional 
Boilers and Process Heaters National Emission Standards for Hazardous 
Air Pollutants'' in the docket.


F. Should EPA Consider Different Subcategories for Solid Fuel Boilers 
and Process Heaters?


    The boilers and process heaters source category is tremendously 
heterogeneous. The EPA has attempted to identify subcategories that 
provide the most reasonable basis for grouping and estimating the 
performance of generally similar units using the available data. We 
believe that the subcategories we selected are appropriate, given the 
variety and combination of fuels that sources in the category burn and 
the fact that any individual unit may use a different combination of 
fuels over time.
    However, among the solid fuel units, the available emission test 
data could suggest that units burning only wood might perform 
sufficiently similar to each other, and sufficiently differently


[[Page 1679]]


from other (fossil fuel burning) solid fuel units, to warrant 
additional subcategorization. Nonetheless, we believe, for purposes of 
today's proposal, that it is appropriate to treat wood burning and non-
wood burning solid fuel units as a single category. We believe, given 
the available data, that this approach most reasonably accounts for 
variations in emissions that can occur as a result of different fuels 
and/or fuel combinations, and changes in fuel use over time, and that 
it provides a reasonable basis for establishing an appropriate 
standard.
    However, if we were to create a separate subcategory for wood 
burning units, we would establish MACT in a manner consistent with the 
approach taken for other solid fuel units. We would identify the types 
of emission control used by the best controlled source (and the top 12 
percent of units in the subcategory), and we would estimate the 
performance of the best controlled units by looking at representative 
emission test data and applying an appropriate variability factor. A 
preliminary review of the wood burning units in the database suggests 
that the MACT floors for such units would probably be related to the 
performance of ESP and/or scrubbers.
    The EPA requests comments on whether additional or different 
subcategories should be considered. Comments should include detailed 
information regarding why a new or different subcategory is appropriate 
(based on the available data or adequate data submitted with the 
comment), how EPA should define any additional/different subcategories, 
how EPA should account for varied or changing fuel mixtures, and how 
EPA should use the available data to determine the MACT floor for any 
new or different categories.


G. How Did EPA Determine the Proposed Emission Limitations for New 
Units?


    All standards established pursuant to section 112 of the CAA must 
reflect MACT, the maximum degree of reduction in emissions of air 
pollutants that the Administrator, taking into consideration the cost 
of achieving such emissions reductions, and any nonair quality health 
and environmental impacts and energy requirements, determines is 
achievable for each category. The CAA specifies that MACT for new 
boilers and process heaters shall not be less stringent than the 
emission control that is achieved in practice by the best-controlled 
similar source--this minimum level of stringency is the MACT floor for 
new units. However, EPA may not consider costs or other impacts in 
determining the MACT floor. The EPA must consider cost, nonair quality 
health and environmental impacts, and energy requirements in connection 
with any standards that are more stringent than the MACT floor (beyond-
the-floor controls).


H. How Did EPA Determine the MACT Floor for New Units?


    Similar to the MACT floor process used for existing units, we 
considered several approaches to identifying MACT floors for new 
industrial, commercial, and institutional boilers and process heaters. 
First, we considered using only the emission test data from boilers and 
process heaters to set the MACT floor. However, as discussed previously 
in this preamble, we determined that it was inappropriate in the 
proposed rulemaking to develop MACT floor emission limits based on HAP 
emissions test information alone.
    We then considered using HAP emission limits contained in State 
regulations and permits as a surrogate to actual emission data in order 
to identify the emissions levels from the best performing units in the 
category for purposes of establishing MACT standards. However, we found 
no State regulations or State permits which specifically limit HAP 
emissions from these sources.
    Consequently, we concluded that the most appropriate approach for 
identifying the top performing units in each subcategory of boilers and 
process heaters is to look at the control technologies used by the 
units within each subcategory. Information was available on the add-on 
control technologies employed by the population of boilers identified 
by the EPA. We considered several possible control options (i.e., 
factors that influence emissions), including fuel substitution, process 
changes and work practices, and add-on control technologies.
    We considered first whether fuel switching would be an appropriate 
control option for sources in each subcategory. We considered the 
feasibility of both fuel switching to other fuels used in the 
subcategory and to fuels from other subcategories. This consideration 
included determining whether switching fuels would achieve lower HAP 
emissions. A second consideration was whether fuel switching could be 
technically achieved by boilers and process heaters in the subcategory 
based on design considerations. We also considered the availability of 
various types of fuel.
    As discussed previously in this preamble, we determined that fuel 
switching was not an appropriate control technology for purposes of 
determining the MACT floor level of control for any subcategory. This 
decision was based on the overall effect of fuel switching on HAP 
emissions, technical and design considerations discussed previously in 
this preamble, and concerns about fuel availability. Additional 
discussion of fuel switching is presented previously in this preamble 
and in the memorandum ``Development of Fuel Switching Costs and 
Emission Reductions for Industrial, Commercial, and Institutional 
Boilers and Process Heaters National Emission Standards for Hazardous 
Air Pollutants'' located in the docket.
    Based on the data available in the emissions database, we 
determined that while fuel switching would decrease some HAP, emissions 
of some organic HAP would increase, resulting in uncertain benefits. We 
believe that it is inappropriate in a MACT rulemaking to consider as 
MACT a control option that potentially will decrease emissions of one 
HAP while increasing emissions of another HAP. A detailed discussion of 
the consideration of fuel switching is discussed previously in this 
preamble.
    We also concluded that process changes or work practices were not 
appropriate criteria for identifying the MACT floor level of control 
for units in the boilers and process heaters category. The HAP 
emissions from boilers and process heaters are primarily dependent upon 
the composition of the fuel. Fuel dependent HAP are metals, including 
mercury, and acid gases. Fuel dependent HAP are typically controlled by 
removing them from the flue gas after combustion. Therefore, they are 
not affected by the operation of the boiler or process heater. 
Consequently, process changes would be ineffective in reducing these 
fuel-related emissions.
    On the other hand, organic HAP can be formed from incomplete 
combustion of the fuel. Combustion is defined as the rapid chemical 
combination of oxygen with the combustible elements of a fuel. The 
objective of good combustion is to release all the energy in the fuel 
while minimizing losses from combustion imperfections and excess air. 
The combination of the fuel with the oxygen requires temperature (high 
enough to ignite the fuel constituents), mixing or turbulence (to 
provide intimate oxygen-fuel contact), and sufficient time (to complete 
the process), sometimes referred to the three Ts of combustion. Good 
combustion practice, in terms of boilers and process heaters, could be 
defined as the system design and work practices expected to minimize 
organic HAP emissions. The GCP control


[[Page 1680]]


strategy could include a number of combustion conditions and work 
practices which are applied collectively to achieve this goal.
    While few sources in EPA's database specifically reported using 
good combustion practices, the data that we have suggests that boilers 
and process heaters within each subcategory might use any of a wide 
variety of different work practices, depending on the characteristics 
of the individual unit. The lack of information, and lack of a uniform 
approach to assuring combustion efficiency, is not surprising given the 
extreme diversity of boilers and process heaters, and given the fact 
that no applicable Federal standards, and most applicable State 
standards, do not include work practice requirements for boilers and 
process heaters. Even those States that do have such requirements do 
not require the same work practices.
    Consequently, EPA was unable to identify any uniform requirements 
or set of work practices that would meaningfully reflect the use of 
good combustion practices, or that could be meaningfully implemented 
across any subcategory of boilers and process heaters. Therefore, EPA 
is not establishing combustion practice requirements as a part of the 
MACT floor for new units. However, we have considered the 
appropriateness of such requirements in the context of evaluating 
possible above the floor options.
    In general, boilers and process heaters are designed for good 
combustion. Facilities have an economic incentive to ensure that fuel 
is not wasted, and the combustion device operates properly and is 
appropriately maintained. In fact, existing boilers and process heaters 
are used as high efficiency control devices to control (reduce) 
emission streams containing organic compounds from various process 
operations. Therefore, EPA's inability to establish a combustion 
practice requirements as a part of the MACT floor for new sources in 
this category should not reduce the incentive for owners and operators 
to run their boilers and process heaters at top efficiency.
    Nonetheless, we consider monitoring and maintaining CO emission 
levels to be associated with minimizing emissions of organic HAP. 
Carbon monoxide is generally an indicator of incomplete combustion 
because CO will burn to carbon dioxide if adequate oxygen is available. 
Therefore, controlling CO emissions can be a mechanism for ensuring 
combustion efficiency and may be viewed as a kind of GCP. As discussed 
previously in this preamble, CO is considered a surrogate for organic 
HAP emissions in the proposed rule.
    To determine if CO monitoring would be the basis of the new source 
MACT floor for organic emissions control, we examined available 
information. The population databases did not contain information on 
existing units monitoring CO emissions. We reviewed State regulations 
applicable to boilers and process heaters that required the use of CO 
monitoring to maintain a specific CO limit. We then matched the 
applicability of each of the State regulations with information on the 
locations and characteristics of the boilers and process heaters in the 
population database for each subcategory to determine if each 
subcategory would have at least one unit that would be required to meet 
the CO requirements. The analysis of the State regulations indicated 
that at least one of the boilers and process heaters in the large and 
limited use subcategories for solid fuel, liquid fuel, and gaseous fuel 
were required to monitor CO emissions and meet a CO limit of 400 parts 
per million. Therefore, the new source MACT floor level of control 
includes a CO work practice standard of 400 parts per million for large 
and limited use units, reflecting the MACT floor level of control for 
emissions of organic HAP.
    We concluded for new units that, except for CO monitoring for 
organic HAP, add-on control technology is the only factor that 
significantly controls emissions. To determine the MACT floor for new 
sources, EPA reviewed the population database of existing major 
sources. Data for units not meeting the definition of an industrial, 
commercial, or institutional boiler or process heater were removed from 
the database. Also, boilers and process heaters that would not be 
covered by the proposed rule, including units located at area source 
facilities, were not included in the analyses. As with the existing 
source analysis, the remaining units in the population database were 
first divided into three subcategories: gaseous fuel-fired units, 
liquid fuel-fired units, and solid fuel-fired units. They were further 
divided into normal use units (units with greater than 10 percent 
capacity utilization) and limited use units (units with less than or 
equal to 10 percent capacity utilization) based on hours of operation 
and additional descriptions provided in the population database. Units 
were further divided into large units (greater than 10 MMBtu/hr heat 
input) and small units (less than or equal to 10 MMBtu/hr heat input).
    Based upon the emission reduction potential of existing air 
pollution control devices, EPA listed all the boilers and process 
heaters in the population database in order of decreasing control 
device effectiveness for each subcategory and each type of pollutant. 
Once the ranking of all existing boilers and process heaters was 
completed for each subcategory and type of pollutant, EPA identified, 
for each grouping, the control technology used by the best controlled 
unit. Then, for each pollutant type in each subcategory, we used the 
available emission test data from units using the best control 
technology to identify the single unit with the best average measured 
performance. We then calculated an emission limit, based on the 
measured performance of this single unit, by applying an appropriate 
variability factor to account for unavoidable variations in emissions 
due to uncontrollable variations in fuel characteristics.
    The approach that we use to calculate the MACT floors for new 
sources is somewhat different from the approach that we use to 
calculate the MACT floors for existing sources. While the MACT floors 
for existing units are intended to reflect the average performance 
achieved by a representative group of sources, the MACT floors for new 
units are meant to reflect the emission control that is achieved in 
practice by the best controlled source. Thus, for existing units, we 
are concerned about estimating the central tendency of a set of 
multiple units, while for new units, we are concerned about estimating 
the level of control that is representative of that achieved by a 
single best controlled source. As with the analysis for existing 
sources the new unit analysis must account for variability. To 
accomplish this for new sources, for the fuel dependent HAP emissions, 
we attempt to determine what the best controlled source can achieve in 
light of the inherent and unavoidable variations in the HAP content of 
the fuel that such unit might potentially use. For non-fuel dependent 
HAP emissions, on the other hand, we look at the inherent variability 
of the control technology used by sources in the category. These 
approaches, respectively, represent the most reasonable way to estimate 
performance for purposes of establishing MACT floors for new units, 
given the data available.
    Thus, for new units, after identifying the best control technology 
for each pollutant group within each subcategory (based on the control 
technology rankings), EPA examined the emissions


[[Page 1681]]


data available for boilers and process heaters controlled by these 
technologies to determine achievable emission levels for PM (as a 
surrogate for non-mercury metallic HAP), total selected non-mercury 
metallic HAP, mercury, HCl (as a surrogate for inorganic HAP), and CO 
(as a surrogate for organic HAP). First, we identified the units using 
the best control technology for which we had emissions data. We then 
averaged the emission data for any unit with multiple test results, and 
rank these units based on the unit by unit average measured emissions 
performance. Then, we identified the unit with the best average 
measured emissions performance. Finally, to estimate the emission 
control achievable by this unit, we applied a variability factor to the 
average measured emissions performance of the best unit. For fuel 
dependent HAP emissions (mercury and HCl), we calculated the 
variability factor by looking at data on HAP variability in coal from 
an analysis of coal properties obtained through a utility-related 
information collection request. We derived the fuel dependent 
variability factor by dividing the highest observed HAP concentration 
by the lowest observed HAP concentration from the utility coal 
analysis. There is no reason to expect that utilities use significantly 
different coal than is available to industrial boilers and process 
heaters, and coal is the solid fuel that is routinely used in such 
units that has generally the greatest degree of HAP variability. Once 
we calculated the fuel dependent variability factors, we applied these 
factors to the average measured emissions performance of the unit with 
the best data to derive the MACT floor level of control. This approach 
reasonably estimates the best source's level of control, adjusted for 
unavoidable variation in fuel characteristics which have a direct 
impact on emissions.
    For non-fuel dependent HAP emissions (PM/metallic HAP), we 
calculated the appropriate variability factor in the same general 
manner as we did for existing units. We calculated a variability factor 
for each unit using the same control technology as the unit with the 
best emissions data, and then calculated the overall variability in the 
measured emissions from units using this technology by averaging all 
the individual unit variability factors. Finally, we applied this 
overall variability factor to the average measured emissions 
performance of the unit with the best emissions data.
    For new unit subcategories where no units in the subcategory 
employed any type of control technology, we could not identify data to 
represent the level of control of the best controlled similar unit. 
Accordingly, the MACT floor level of control for such subcategories is 
no emissions reductions.
    A detailed description of the MACT floor determination is in the 
memorandum ``MACT Floor Analysis for Industrial, Commercial, and 
Institutional Boilers and Process Heaters National Emission Standards 
for Hazardous Air Pollutants'' in the docket.
1. New Solid Fuel-Fired Units
    a. Large Units--Heat Inputs Greater than 10 MMBtu/hr. The most 
effective control technology identified for removing non-mercury 
metallic HAP and PM is fabric filters. Therefore, because there are no 
options reasonably available for reducing non-mercury metallic HAP 
emissions other than add-on control, we consider a source with a fabric 
filter to be the best controlled similar unit in this subcategory for 
purposes of non-mercury metallic HAP and PM emissions. Thus, it is 
appropriate to use the measured performance of the best controlled 
source with a fabric filter as the basis for establishing the MACT 
floor for non-mercury metallic HAP and PM for new boilers and process 
heaters in this subcategory.
    As described earlier, a PM level is set as a surrogate for non-
mercury metallic HAP. The MACT floor emission level based on PM test 
data from the solid fuel unit with a fabric filter representing the 
best controlled similar unit, and incorporating operational 
variability, is 0.026 lb PM/MMBtu. We are also providing an alternative 
metals limit of 0.0001 lb metals/MMBtu which can be used to show 
compliance in cases where metals HAP emissions are low in proportion to 
PM emissions. This is because, according to the emissions database, 
some biomass units have low metals content but high PM emissions. The 
emission level for metals was selected from metals test data associated 
with PM emission tests from fabric filters that met the MACT floor PM 
emission level.
    The most effective control technologies identified for removing 
inorganic HAP including acid gases, such as HCl, are wet or dry 
scrubbers. Wet scrubbers is a generic term that is most often used to 
describe venturi scrubbers, but can include packed bed scrubbers, 
impingement scrubbers, etc. One percent of boilers and process heaters 
in this subcategory reported using a packed bed scrubber. Emission test 
data from other industries suggests that packed bed scrubbers achieve 
consistently lower emission levels than other types of wet scrubbers. 
Because there are no options reasonably available for reducing HCl 
emissions other than add-on control, we consider a source with a packed 
bed scrubber to be the best controlled similar source in this 
subcategory for purpose of HCl emissions. The MACT floor emission level 
based on HCl test data from the solid fuel unit with a wet scrubber 
representing the best controlled similar unit, and incorporating 
operational variability, is 0.02 lb HCl/MMBtu.
    For mercury control, one technology, carbon injection, that has 
demonstrated mercury reductions in other source categories (i.e., 
municipal waste combustors), was identified as being used on one 
existing industrial boiler. However, test data on this carbon injection 
system indicated that this unit was not achieving mercury emissions 
reductions. Therefore, we did not consider carbon injection to be a 
MACT floor control technology for industrial, commercial, and 
institutional boilers and process heaters. Data from electric utility 
boilers indicate that fabric filters are the most effective technology 
for controlling mercury emissions. Therefore, we consider a source with 
a fabric filter to be the best controlled similar source in this 
subcategory for purpose of mercury emissions. The MACT floor emission 
level based on mercury test data from the solid fuel unit with a fabric 
filter representing the best controlled similar unit, and incorporating 
operational variability, is 0.000003 lb mercury/MMBtu.
    Although EPA used information from utility boilers to conclude that 
fabric filters are the most effective control technology for 
controlling mercury emissions, this same information suggests that 
different fuel characteristics (e.g. mercury and chlorine content of 
the fuel burned) can lead to different outlet Hg concentrations and 
different control efficiencies for equivalent control devices. We have 
information about the general type of fuel being burned during the 
emission tests. However, we have no detailed information about the 
specific characteristics (such as mercury or chlorine content) of the 
fuel being burned during the emissions tests for the best controlled 
source. Nonetheless, EPA believes that the use of variability factors 
adequately accounts for potential variations in fuel mercury and 
chloride content.
    However, because we have very limited data on actual emissions from 
industrial boilers and process heaters, the Agency is soliciting 
comment on whether the variability analysis in the


[[Page 1682]]


current proposal adequately addresses the impact that fuel 
characteristics (such as mercury and chlorine content) can have on 
mercury emissions from sources equipped with fabric filters. As 
discussed earlier, the Agency is not currently considering fuel 
switching as a control option in setting the MACT floor. Therefore, the 
Agency requests specific information regarding both the mercury and 
chlorine content characteristics of the fuel used in, and the mercury 
emissions from, industrial boilers and process heaters equipped with 
well designed and operated fabric filters.
    Comments on this issue should include specific data regarding both 
the characteristics of the fuel burned (including mercury and chlorine 
content along with any other pertinent characteristics) and current 
mercury emissions of these industrial boilers and process heaters.
    Similar control technology analysis was done for the boilers and 
process heaters in this subcategory for organic HAP. One control 
technique, controlling inlet temperature to the PM control device, that 
has demonstrated controlling downstream formation of dioxins in other 
source categories (e.g., municipal waste combustors) was analyzed for 
industrial boilers. Inlet and outlet dioxins test data were available 
on four boilers controlled with PM control devices. In all cases, no 
increase in dioxins emissions were indicated across the PM control 
device even at high inlet temperatures. However, we are requesting 
comment on controls that would achieve reductions of organic HAP, 
including any additional data that might be available. The EPA did find 
that CO monitoring can reduce organic HAP emissions, and has included 
it in the new source MACT floors as described previously in this 
preamble.
    In light of this analysis, EPA determined that, in general, the 
combination of a fabric filter, a packed bed scrubber, and CO 
monitoring forms the basis for the MACT floor level of control for new 
solid fuel boilers and process heaters in this subcategory.
    b. Small Units--Heat Inputs Less than or Equal to 10 MMBtu/hr. The 
most effective control technology identified for removing non-mercury 
metallic HAP and PM is fabric filters. Because there are no options 
reasonably available for reducing non-mercury metallic HAP emissions 
other than add-on control, we consider a source with a fabric filter to 
be the best controlled similar unit in this subcategory for purposes of 
non-mercury metallic HAP and PM emissions. The most effective control 
technology identified for units in this subcategory for removing acid 
gases, such as HCl, is wet scrubbers. The most effective control 
technology identified for removing mercury is fabric filters.
    The EPA identified no control technology being used in the existing 
population of boilers and process heaters that consistently achieved 
lower emission rates than uncontrolled levels, such that a best 
controlled similar source for organic HAP could be identified. 
Therefore, we concluded that the MACT floor for new sources in this 
subcategory is no emissions reductions for organic HAP. Furthermore, CO 
monitoring is not required for small boilers and process heaters by any 
State rules.
    Consequently, EPA determined that the combination of a fabric 
filter and a wet scrubber forms the basis for the MACT floor level of 
control for new solid fuel boilers and process heaters in this 
subcategory.
    The emissions database did not contain test data for boilers and 
process heaters less than 10 MMBtu/hr heat input. In order to develop 
emission levels for this subcategory, we decided to use test data from 
units in the large solid subcategory. We considered this to be an 
appropriate methodology because although the units in this subcategory 
are different enough to warrant their own subcategory (i.e., different 
designs and emissions), emissions of the specific HAP for which limits 
are being proposed (HCl, mercury, PM and metals) are expected to be 
related more to the type of fuel burned and the type of control used 
than to the unit design. Consequently, we determined that emissions 
test data from units greater than 10 MMBtu/hr heat input could be used 
to establish the MACT floor levels for this subcategory for HCl, PM, 
non-mercury metallic HAP (using PM as a surrogate), and mercury because 
the fuels and controls are similar.
    The MACT floor emission levels based on emissions data from the 
unit representing the best controlled similar source, and incorporating 
operational variability, are 0.026 lb PM/MMBtu or 0.0001 lb selected 
non-mercury metals/MMBtu, 0.000003 lb mercury/MMBtu, and 0.02 lb HCl/
MMBtu. We are requesting comment on using emission data from another 
subcategory to develop emission levels for this subcategory. We are 
also requesting any available emissions information for this 
subcategory.
    c. Limited Use Units--Capacity Utilizations Less than or Equal to 
10 Percent. The most effective control technology identified for 
removing non-mercury metallic HAP, PM, and mercury is fabric filters. 
Therefore, we consider a source with a fabric filter to be the best 
controlled similar unit in this subcategory for purposes of non-mercury 
metallic HAP, PM, and mercury emissions. The most effective control 
technology identified for units in this subcategory for removing acid 
gases, such as HCl, is wet scrubbers.
    The EPA did find that monitoring CO is used by at least one unit 
and can minimize organic HAP emissions, and has included it in the new 
source MACT floor for this subcategory as described previously in this 
preamble.
    Therefore, based on this analysis, EPA determined that the 
combination of a fabric filter, a wet scrubber, and CO monitoring forms 
the basis for the MACT floor level of control for new solid fuel 
boilers and process heaters in this subcategory.
    The emissions test database did not contain test data for limited 
use boilers and process heaters. In order to develop emission levels 
for this subcategory, we decided to use test data from units in the 
large solid fuel subcategory. We considered this to be an appropriate 
methodology because although the units in this subcategory are 
different enough to warrant their own subcategory (i.e., different 
purposes and operation), emissions of the specific types of HAP for 
which limits are being proposed (HCl, mercury, and metals) are expected 
to be related more to the type of fuel burned and the type of control 
used, than to unit operation. Consequently, we determined that 
emissions information from the large solid fuel subcategory could be 
used to establish MACT floor levels for this subcategory because the 
fuels and controls are similar. The MACT floor emission levels based on 
test data from unit representing the best controlled similar source, 
and incorporating operational variability, are 0.026 lb PM/MMBtu or 
0.0001 lb metals/MMBtu, 0.000003 lb mercury/MMBtu, and 0.02 lb HCl/
MMBtu. We are requesting comment on using emission data from another 
subcategory to develop emission levels for this subcategory. We are 
also requesting any available emissions information for this 
subcategory.
2. New Liquid Fuel-Fired Units
    a. Large Units--Heat Inputs Greater than 10 MMBtu/hr. The most 
effective control technology identified for removing non-mercury 
metallic HAP and PM is ESP. Therefore, because there are no options 
reasonably available for reducing non-mercury metallic HAP emissions 
other than add-on control, we consider a source with an ESP to be the 
best controlled similar unit in this subcategory for purposes of non-


[[Page 1683]]


mercury metallic HAP and PM emissions.
    As discussed earlier, a PM level is set as a surrogate for non-
mercury metallic HAP. The emissions database did not contain test data 
for boilers and process heaters with ESP. In order to develop a PM 
emission level for this subcategory, we decided to use test data from 
oil-fired utility boilers controlled with ESP. We considered this to be 
an appropriate methodology because although the units in this 
subcategory are generally smaller than utility boilers, emissions of 
the specific HAP for which limits are being proposed (PM as a surrogate 
for metals) are expected to be related more to the type of fuel burned 
and the type of control used than to the size of the unit. 
Consequently, we determined that emissions test data from oil-fired 
utility boilers could be used to establish the MACT floor levels for 
this subcategory for non-mercury metallic HAP (using PM as a surrogate) 
because the fuels and controls are similar.
    The MACT floor emission level based on PM emissions data from the 
unit representing the best controlled similar source, and incorporating 
operational variability, is 0.03 lb PM/MMBtu. Unlike for solid fuel 
subcategories, we are not aware of any liquid fuels that are low in 
metals but would have high PM emissions. Therefore, we are not 
proposing an alternative metals standard for the liquid subcategories.
    The most effective control technology identified for removing 
inorganic HAP that are acid gases, such as HCl, are packed bed 
scrubbers. Because there are no options reasonably available for 
reducing HCl emissions other than add-on control, we consider a source 
with a packed bed scrubber to be the best controlled similar source in 
this subcategory for purpose of HCl emissions. The emissions database 
did not contain HCl test data for liquid fuel boilers and process 
heaters. In order to develop a HCl emission level for this subcategory, 
we decided to use available fuel analysis data from oil-fired units and 
emission reduction performance of well designed and operated packed bed 
scrubbers. We considered this to be an appropriate methodology because 
this approach reasonably estimates the best source's level of control, 
adjusted for unavoidable variation in fuel characteristics which have a 
direct impact on emissions. The MACT floor emission level based on the 
estimated performance from a liquid fuel unit with a packed scrubber 
representing the best controlled similar unit, and incorporating 
operational variability, is 0.0005 lb HCl/MMBtu.
    Similar control technology analyses were done for the boilers and 
process heaters in this subcategory for mercury and organic HAP.
    Information in the emissions database or from other source 
categories does not show that control technologies, such as fabric 
filters, ESP, or wet scrubbers, achieve reductions in mercury emissions 
from liquid fuel-fired industrial, commercial, and institutional 
boilers and process heaters. Therefore, EPA identified no control 
technology being used in the existing population of boilers and process 
heaters in these subcategories that consistently achieved lower 
emission rates than uncontrolled levels, such that a best controlled 
similar source for organic HAP could be identified. However, we did 
find that monitoring CO is a good combustion practice that can reduce 
organic HAP emissions, and have included it in the new source MACT 
floor as described previously in this preamble. We concluded the MACT 
floor for new sources in this subcategory is no emissions reductions 
for mercury.
    In light of this analysis, the EPA determined that, in general, the 
combination of an ESP, a packed bed scrubber, and CO monitoring forms 
the basis for the MACT floor level of control for new liquid fuel 
boilers and process heaters in this subcategory.
    b. Small Units--Heat Inputs Less than or Equal to 10 MMBtu/hr. The 
most effective control technology identified for removing non-mercury 
metallic HAP used by units in this subcategory is ESP. Therefore, 
because there are no options reasonably available for reducing non-
mercury metallic HAP emissions other than add-on control, we consider a 
source with an ESP to be the best controlled similar unit in this 
subcategory for purposes of non-mercury metallic HAP and PM emissions. 
The most effective control technology identified for units in this 
subcategory for removing acid gases, such as HCl, is wet scrubbers.
    Information in the emissions database or from other source 
categories does not show that control technologies, such as fabric 
filters, ESP, or wet scrubbers, achieve reductions in mercury emissions 
from liquid fuel-fired industrial, commercial, and institutional 
boilers and process heaters. Therefore, EPA could not identify a 
control technology being used in the existing population of boilers and 
process heaters that consistently achieved lower emission rates than 
uncontrolled levels, such that a best controlled similar source for 
mercury or organic HAP could be identified. We concluded the MACT floor 
for new sources in this subcategory is no emissions reductions for 
mercury or organic HAP.
    Thus, EPA determined that the combination of a fabric filter and a 
wet scrubber forms the basis for the MACT floor level of control for 
new liquid fuel boilers and process heaters in this subcategory.
    The emissions test database did not contain test data for liquid 
fuel boilers and process heaters less than 10 MMBtu/hr heat input 
capacity. In order to develop emission levels for this subcategory, we 
decided to use information from units in the large liquid fuel 
subcategory. We considered this to be an appropriate methodology 
because although the units in this subcategory are different enough to 
warrant their own subcategory (i.e., different designs and emissions), 
emissions of the specific types of HAP for which limits are being 
proposed (HCl and metals) are expected to be more related to the type 
of fuel burned and the type of control than to unit design. 
Consequently, we determined that emissions information from units 
greater than 10 MMBtu/hr heat input capacity could be used to establish 
MACT floor levels for this subcategory because the fuels and controls 
are similar. The MACT floor emission level based on PM test data from a 
liquid fuel unit with an ESP representing the best controlled similar 
unit, and incorporating operational variability, is 0.03 lb PM/MMBtu. 
The MACT floor emission level based on a liquid fuel unit with a wet 
scrubber representing the best controlled similar unit, and 
incorporating operational variability, is 0.0009 lb HCl/MMBtu. We are 
requesting comment on using emission data from another subcategory to 
develop emission levels for this subcategory. We are also requesting 
any available emissions information for this subcategory.
    c. Limited Use Units--Capacity Utilizations Less than or Equal to 
10 Percent. The most effective control technology identified for 
removing non-mercury metallic HAP used by units in this subcategory is 
ESP. Therefore, because there are no options reasonably available for 
reducing non-mercury metallic HAP emissions other than add-on control, 
we consider a source with an ESP to be the best controlled similar unit 
in this subcategory for purposes of non-mercury metallic HAP and PM 
emissions. The most effective control technology identified for units 
in this subcategory for removing acid gases, such as HCl, is wet 
scrubbers.
    Information in the emissions database or from other source 
categories does not show that other control technologies,


[[Page 1684]]


such as fabric filters, ESP, or wet scrubbers, achieve reductions in 
mercury emissions from liquid fuel-fired industrial, commercial, and 
institutional boilers and process heaters. The EPA identified no 
control technology being used in the existing population of boilers and 
process heaters that consistently achieved lower emission rates than 
uncontrolled levels, such that a best controlled similar source for 
mercury could be identified. We concluded the MACT floor for new 
sources in this subcategory is no emissions reductions for mercury.
    We did find that monitoring CO can reduce organic HAP emissions and 
is used by at least one unit in this subcategory, and have included it 
in the new source MACT floor as described previously in this preamble.
    Therefore, based on this analysis, EPA determined that the 
combination of a fabric filter, a wet scrubber, and CO monitoring forms 
the basis for the MACT floor level of control for new liquid fuel 
boilers and process heaters in this subcategory.
    The emissions test database did not contain test data for limited 
use liquid fuel boilers and process heaters. In order to develop 
emission levels for this subcategory, we decided to use information 
from units in the large liquid fuel subcategory. We considered this to 
be an appropriate methodology because although the units in this 
subcategory are different enough to warrant their own subcategory 
(i.e., different purposes and operation), emissions of the specific HAP 
for which limits are being proposed (HCl and metals) are more related 
to the type of fuel burned and the type of control used than to unit 
operation. Consequently, we determined that emissions information from 
units greater than 10 MMBtu/hr heat input capacity could be used to 
establish MACT floor levels for this subcategory because the fuels and 
controls are similar. The MACT floor emission level based on PM test 
data from a liquid fuel unit with an ESP representing the best 
controlled similar unit, and incorporating operational variability, is 
0.03 lb PM/MMBtu. The MACT floor emission level based on a liquid fuel 
unit with a wet scrubber representing the best controlled similar unit, 
and incorporating operational variability, is 0.0009 lb HCl/MMBtu. We 
are requesting comment on using emission data from another subcategory 
to develop emission levels for this subcategory. We are also requesting 
any available emissions information for this subcategory.
3. Gaseous Fuel Subcategories
    No existing units were using control technologies that achieve 
consistently lower emission rates than uncontrolled sources for any of 
the pollutant groups of interest, except organic HAP. At least one unit 
in the population database in the large and limited use gaseous fuel 
subcategories is required to monitor CO. Therefore, the MACT floor for 
gaseous fuel-fired units includes a CO monitoring requirement and 
emission limit, as described previously in this preamble, but it does 
not include any emission limits for PM, metallic HAP, mercury, or 
inorganic HAP based on the utilization of add-on control technology.


I. How Did EPA Consider Beyond-the-Floor for New Units?


    The MACT floor level of control for new units is based on the 
emission control that is achieved in practice by the best controlled 
similar source within each of the subcategories. No technologies were 
identified that would achieve non-mercury metals reduction greater than 
the new source floors for the liquid and solid subcategories or CO 
monitoring for the solid, liquid, and gaseous subcategories. For 
inorganic HAP control, we determined that packed bed scrubbers achieve 
higher emissions reductions than MACT floors consisting of a wet 
scrubber. Packed bed scrubbers are the technology basis of the MACT 
floor for the large unit subcategory, but wet scrubbers were the 
technology basis of the floors for the small unit and limited unit 
subcategories. Therefore, we examined the cost and emission reduction 
benefits of applying a packed bed scrubber as a beyond-the-floor option 
for new solid and liquid units within the small and limited use 
subcategories. The results of this analysis indicated that annualized 
costs would be an additional 2 million dollars per year for additional 
reductions of approximately three tons of HCl per year. We determined 
that costs were excessive for the limited emissions reductions that 
would be achieved. Nonair quality health, environmental impacts, and 
energy effects were not significant factors, because there would be 
little difference in the nonair quality health and environmental 
impacts between packed bed scrubbers and wet scrubbers. Therefore, EPA 
did not select this beyond-the-floor option, and the proposed new 
source MACT level of control for PM, metallic HAP, and inorganic HAP 
(HCl) is the same as the MACT floor level of control for all of the 
subcategories.
    In reviewing potential regulatory options beyond the new source 
MACT floor level of control, EPA identified one existing solid fuel-
fired industrial boiler that was using carbon injection technology for 
mercury control. However, emission data obtained from this unit 
indicated that it was not achieving mercury emission reduction from the 
uncontrolled levels. Moreover, we do not have information to otherwise 
show that carbon injection is effective for reducing mercury emissions 
from industrial, commercial, and institutional boilers and process 
heaters. Information in the emissions database or from other source 
categories does not show that other control technologies, such as 
fabric filters, ESP, or wet scrubbers, achieve reductions in mercury 
emissions from liquid fuel-fired industrial, commercial, and 
institutional boilers and process heaters. Therefore, carbon injection, 
for solid fuel units, and other control techniques, for liquid fuel 
units, were not evaluated as regulatory options. However, EPA requests 
comments on whether carbon injection and/or other control techniques 
should be considered as beyond-the-floor options and whether new 
industrial, commercial, or institutional boilers and process heaters 
could use carbon injection technology, or other control techniques to 
consistently achieve mercury emission levels that are lower than levels 
from similar sources without such controls. Comments should include 
information on emissions, current demonstrated applications, and costs.
    For the solid fuel and liquid fuel subcategories, fuel switching to 
natural gas is a potential regulatory option beyond the new source 
floor level of control that would reduce mercury and metallic HAP 
emissions. However, based on current trends within the industry, EPA 
projects that the majority of new boilers and process heaters will be 
built to fire natural gas as opposed to solid and liquid fuels such 
that the overall emissions reductions associated with this option would 
be minimal while the total cost of fuel switching would be 
approximately 600 million dollars. The additional emissions reductions 
would be 30 tons per year of HCl, 90 tons per year of inorganic HAP and 
120 tons per year of total non-mercury metallic HAP. Section III.D of 
this preamble provides additional rationale for not going beyond the 
floor to require fuel switching. For example, natural gas supplies are 
not available in some areas, and supplies to industrial customers can 
be limited during periods when natural gas demand exceeds


[[Page 1685]]


supply. Thus, this potential control option may be unavailable to many 
sources in practice. Furthermore, organic HAP may be increased by fuel 
switching. Limited emissions reductions in combination with the high 
cost of fuel switching and considerations about the availability and 
technical feasibility of fuel switching makes this an unreasonable 
regulatory option that was not considered further. Nonair quality 
health, environmental impacts, and energy effects were not significant 
factors. No beyond-the-floor options for gas-fired boilers were 
identified.
    Based on the analysis discussed above, EPA decided to not go beyond 
the MACT floor level of control for new sources for MACT in the 
proposed rule. A detailed description of the beyond-the-floor 
consideration is in the memorandum ``Methodology for Estimating Cost 
and Emissions Impacts for Industrial, Commercial, Institutional Boilers 
and Process Heaters National Emission Standards for Hazardous Air 
Pollutants'' in the docket.


J. How Did EPA Determine Testing and Monitoring Requirements for the 
Proposed Rule?


    The CAA requires us to develop regulations that include monitoring 
and testing requirements. The purpose of these requirements is to allow 
us to determine whether an affected source is operating in compliance 
with the proposed rule. The proposed monitoring and testing 
requirements are discussed below.
1. Testing
    The proposed rule requires you to perform an initial performance 
test for PM (or total selected metals), mercury, and HCl if you are 
required to meet an emission limit. Additionally, the proposed rule 
requires annual performance tests to ensure on an ongoing basis that 
the air pollution control device is operating properly and its 
performance has not deteriorated. The majority of emissions tests upon 
which the proposed emission limits are based were conducted using 
approved EPA test methods.
    If you conduct a performance test, you would also determine 
parameter operating limits during the tests. The majority of test 
methods that the proposed rule would require for the performance tests 
have been required under many other EPA standards. No applicable 
voluntary consensus standards were identified.
    If you are required to meet an HCl emission limit and do not have a 
scrubber or elect to take no credit for the scrubber emissions 
reductions, you must record the average chlorine content level in the 
input fuel as an operating limit. However, if you plan to burn a new 
fuel, a fuel from a new mixture, or a fuel from a new supply than what 
was burned during the initial performance test, then you must 
recalculate the chlorine input. If the results of recalculating the 
chlorine input exceeds the average chlorine level established during 
the initial performance test, you must conduct a new performance test 
to demonstrate compliance with the emission level.
    We are also allowing you to record the mercury in the input fuels 
as an operating limit if you elect to take no credit for the control 
device emission reduction. However, if you plan to burn a new fuel, a 
fuel from a new mixture, or a fuel from a new supply than what was 
burned during the initial performance test, then you must recalculate 
the mercury input. If the results of the recalculation exceed the 
average level established during the initial performance test, you must 
conduct a new performance test to demonstrate compliance with the 
mercury emission level.
    We are also allowing you to record the total selected metals in the 
input fuels as an operating limit if you choose to comply with the 
metals emission limit instead of the PM limit. However, if you plan to 
burn a new fuel, a fuel from a new mixture, or a fuel from a new supply 
than what was burned during the initial performance test, then you must 
recalculate the total selected metals input. If the results of the 
recalculation exceed the average level established during the initial 
performance test, you must conduct a new performance test to 
demonstrate compliance with the metals emission level.
2. Continuous Monitoring
    The most direct means of ensuring compliance with emission limits 
is the use of continuous emission monitoring systems (CEMS). We 
consider other options when CEMS are not available or when the impacts 
of including such requirements are considered unreasonable. When 
monitoring options other than CEMS are considered, it is often 
necessary for us to balance more reasonable costs against the quality 
or accuracy of the actual emissions monitoring data. Although 
monitoring of operating parameters cannot provide a direct measurement 
of emissions, it is often a suitable substitute for CEMS. The 
information provided can be used to ensure that air pollution control 
equipment is operating properly. Because the parameter requirements are 
calibrated during the initial and annual stack tests, they provide a 
reasonable surrogate for direct monitoring of emissions. This 
information reasonably assures the public that the reductions 
envisioned by the proposed rule are being achieved.
    The EPA evaluated the cost of applying HCl CEMS to boilers and 
process heaters. For HCl CEM monitoring, capital costs were estimated 
to be $88,000 per unit and annualized costs were estimated to be 
$33,000 per unit. We determined the costs would make them an 
unreasonable monitoring option. In addition, toxic metals are not 
directly measurable with CEMS, and CEMS for PM have not been 
demonstrated in the United States for the purpose of determining 
compliance.
    To ensure continuous compliance with the proposed emission limits 
and/or operating limits, the proposed rule would require continuous 
parameter monitoring of control devices and recordkeeping. We selected 
the following requirements based on reasonable cost, ease of execution, 
and usefulness of the resulting data to both the owners or operators 
and EPA for ensuring continuous compliance with the emission limits 
and/or operating limits.
    We are proposing that certain parameters be continuously monitored 
for the types of control devices commonly used in the industry. These 
parameters include opacity monitoring except for wet scrubbers; pH, 
pressure drop and liquid flow-rate for wet scrubbers; and sorbent 
injection rate for dry scrubbers. You must also install a bag leak 
detection system for fabric filters. If you cannot monitor opacity for 
control systems with an ESP then you must monitor the secondary current 
and voltage or total power input for the ESP. These monitoring 
parameters have been used in other standards for similar industries. 
The values of these parameters are established during the initial or 
most recent performance test that demonstrates compliance. These values 
are your operating limits for the control device.
    You would be required to set parameters based on 1-hour block 
averages during the compliance test, and demonstrate continuous 
compliance by monitoring 3-hour block average values for most 
parameters. We selected this averaging period to reflect operating 
conditions during the performance test to ensure the control system is 
continuously operating at the same or better level as during a 
performance test demonstrating compliance with the emission limits.


[[Page 1686]]


    To demonstrate continuous compliance with the emission and 
operating limits, you would also need daily records of the quantity, 
type, and origin of each fuel burned and hours of operation of the 
affected source. If you are complying with the chlorine or total 
selected metals fuel input option, you must keep records of the 
calculations supporting your determination of the chlorine and total 
selected metals content in the fuel.


K. How Did EPA Determine Compliance Times for the Proposed Rule?


    Section 112 of the CAA specifies the dates by which affected 
sources must comply with the emission standards. New or reconstructed 
units must be in compliance with the proposed rule immediately upon 
startup or [DATE THE FINAL RULE IS PUBLISHED IN THE FEDERAL REGISTER], 
whichever is later. Existing sources are allowed 3 years to comply with 
the final rule. This is the maximum period allowed by the CAA. We 
believe that 3 years for compliance is necessary to allow adequate time 
to design, install and test control systems that will be retrofitted 
onto existing boilers, as well as obtain permits for the use of add-on 
controls.


L. How Did EPA Determine the Required Records and Reports for the 
Proposed Rule?


    You would be required to comply with the applicable requirements in 
the NESHAP General Provisions, subpart A of 40 CFR part 63, as 
described in Table 10 of the proposed subpart DDDDD. We evaluated the 
General Provisions requirements and included those we determined to be 
the minimum notification, recordkeeping, and reporting necessary to 
ensure compliance with, and effective enforcement of, the proposed 
rule.
    We are also requiring that you keep daily records of the total fuel 
use by each affected source, subject to an emission limit or work 
practice standard, along with a description of the fuel, the total fuel 
usage amounts and units of measure, and information on the supplier and 
original source of the fuel. This information is necessary to ensure 
that the affected source is complying with the emission limits from the 
correct subcategory.
    We are requiring additional recordkeeping if you choose to comply 
with the chlorine, mercury or total selected metals fuel input option. 
You will need to keep records of the calculations and supporting 
information used to develop the chlorine, mercury, or total selected 
metals fuel input operating limit.


M. How Does the Proposed Rule Affect Permits?


    The CAA requires that sources subject to the proposed rule be 
operated pursuant to a permit issued under EPA-approved State operating 
permit program. The operating permit programs are developed under title 
V of the CAA and the implementing regulations under 40 CFR parts 70 and 
71. If you are operating in the first 3 years of your operating permit, 
you will need to obtain a revised permit to incorporate the proposed 
rule. If you are in the last 2 years of your operating permit, you will 
need to incorporate the proposed rule into the next renewal of your 
permit.


N. What Alternative Provisions Are Being Considered?


    The EPA is considering a bubbling compliance alternative for 
determining compliance with the non-mercury metallic HAP, HCl, mercury, 
and PM standards for existing sources. The bubbling compliance 
alternative would allow owners and operators to set non-mercury metals, 
mercury, HCl, and PM emissions limits for each existing boiler or 
process heater in the same subcategory such that if these limits are 
met, the total emissions from all existing boilers or process heaters 
in the subcategory are less than or equal to a subcategory specific 
bubble limit. The subcategory specific bubble limit would be the 
proposed emissions limits for non-mercury metallic HAP, mercury, HCl, 
and PM.
    The bubbling compliance alternative would not be applicable to new 
sources and could only be used between boilers and process heaters in 
the same subcategory. For example, bubbling between a solid fuel-fired 
boiler greater than 10 million Btu/hour could only be conducted with 
other solid fuel-fired boilers or process heaters with heat input 
capacities greater than 10 million Btu/hour. Also, owners or owners of 
existing sources subject to the Industrial Boiler New Source 
Performance Standards (NSPS) (40 CFR part 60, subparts Db and Dc) would 
be required to continue to meet the PM emission standard of that NSPS 
regardless of whether they are complying with the bubbling alternative 
or not (because the NSPS is a separate regulatory requirement which 
remains in place).
    Owners or operators that would choose to comply with the HAP 
metals, mercury, HCl, or PM standards using the bubbling compliance 
alternative would be required to submit HAP metals, mercury, HCl, and/
or PM emissions limits to the Administrator for approval for each 
existing source included in the bubbling compliance alternative. Before 
emissions limits would be approved, the owner or operator would need to 
submit documentation demonstrating that if the emissions limits for 
each source (e.g., each boiler or heater) are met, the entire group of 
sources within the bubbling compliance alternative would be in 
compliance with the subcategory-wide allowable non-mercury metallic 
HAP, mercury, HCl, and PM emission levels. Once approved by the 
Administrator, the non-mercury metallic HAP, mercury, HCl, and PM 
emissions levels would be incorporated into the operating permit for 
the source. Thereafter, the owner and operator of the facility would 
demonstrate compliance with the standards by demonstrating that each 
boiler or process heater included in the bubbling compliance 
alternative emits less than or equal to the approved non-mercury 
metallic HAP, mercury, HCl, and PM emissions limits for that source.
    The EPA is considering this bubbling compliance alternative as part 
of the EPA's general policy of encouraging the use of flexible 
compliance approaches where they can be properly monitored and 
enforced. Emissions averaging can provide sources the flexibility to 
comply in the least costly manner while still maintaining regulation 
that is workable and enforceable. However, to implement this 
alternative, the final rule will need to define the affected source 
more broadly to include all the existing boilers and process heaters 
for each subcategory located at the same facility. Therefore, EPA is 
soliciting comments on the bubbling compliance alternative, whether EPA 
should specify this bubbling compliance alternative in the final rule, 
and whether new units added to an existing affected source should be 
included as part of, and applicable to, the existing source bubble 
limit. Comments should include information on the potential cost 
savings a facility could expect from implementation of the bubbling 
compliance provision, along with supporting documentation for this 
estimated cost saving.


IV. Impacts of the Proposed Rule


A. What Are the Air Impacts?


    Table 2 of this preamble illustrates, for each subcategory, the 
emissions reductions achieved by the proposed rule (i.e., the 
difference in emissions between a boiler or process heater controlled 
to the floor level of control and boilers or process heaters at the 
current baseline) for new and existing sources. Nationwide emissions of


[[Page 1687]]


selected HAP (i.e., HCl, hydrogen fluoride, lead, and nickel) will be 
reduced by 58,500 tons per year for existing units and 73 tons per year 
for new units. Emissions of HCl will be reduced by 42,000 tons per year 
for existing units and 72 tons per year for new units. Emissions of 
mercury will be reduced by 1.9 tons per year for existing units and 
0.006 tons per year for new units. Emissions of PM will be reduced by 
565,000 tons per year for existing units and 480 tons per year for new 
units. Emissions of total selected non-mercury metals (i.e., arsenic, 
beryllium, cadmium, chromium, lead, manganese, nickel, and selenium) 
will be reduced by 1,100 tons per year for existing units and will be 
reduced by 1.4 tons per year for new units. In addition, emissions of 
sulfur dioxide are established to be reduced by 113,000 tons per year 
for existing sources and 110 tons per year for new sources. A 
discussion of the methodology used to estimate emissions and emissions 
reductions is presented in ``Estimation of Baseline Emissions and 
Emissions Reductions for Industrial, Commercial, and Institutional 
Boilers and Process Heaters'' in the docket.


                     Table 2.--Summary of Emissions Reductions for Existing and New Sources
                                                    [Tons/yr]
----------------------------------------------------------------------------------------------------------------
                                                                                       Non mercury
              Source                     Subcategory            HCl           PM        metals a       Mercury
----------------------------------------------------------------------------------------------------------------
Existing Units....................  Large solid units....      42,100        560,000      1,100          2
                                    Small solid units....           0              0          0          0
                                    Limited use solid               0          2,800          8          0.002
                                     units.
                                    Liquid units.........           0              0          0          0
                                    Gaseous units........           0              0          0          0
New Units.........................  Large solid units....          70             31          0.01       0.006
                                    Small solid units....           2.4          440          1.4        0.0006
                                    Limited use solid               0.2           11          0.02       0.00002
                                     units.
                                    Liquid units.........           0              0          0          0
                                    Gaseous units........           0              0          0         0
----------------------------------------------------------------------------------------------------------------
a Includes arsenic, beryllium, cadmium, chromium, lead, manganese, nickel, and selenium.


B. What Are the Water and Solid Waste Impacts?


    The EPA estimated the additional water usage that would result from 
the MACT floor level of control to be 110 million gallons per year for 
existing sources and 0.6 million gallons per year for new sources. In 
addition to the increased water usage, an additional 3.7 million 
gallons per year of wastewater would be produced for existing sources 
and 0.6 million gallons per year for new sources. The costs of treating 
the additional wastewater are $18,000 for existing sources and $2,300 
for new sources. These costs are accounted for in the control costs 
estimates.
    The EPA estimated the additional solid waste that would result from 
the MACT floor level of control to be 102,000 tons per year for 
existing sources and 1 ton per year for new sources. The costs of 
handling the additional solid waste generated are $1.5 million for 
existing sources and $17,000 for new sources. These costs are also 
accounted for in the control costs estimates.
    A discussion of the methodology used to estimate impacts is 
presented in ``Estimation of Impacts for Industrial, Commercial, and 
Institutional Boilers and Process Heaters NESHAP'' in the Docket.


C. What Are the Energy Impacts?


    The EPA expects an increase of approximately 1,130 million kilowatt 
hours (kWh) in national annual energy usage as a result of the proposed 
rule. Of this amount, 1,120 million kWh would be from existing sources 
and 13 million kWh are estimated from new sources. The increase results 
from the electricity required to operate control devices installed to 
meet the proposed rule, such as wet scrubbers and fabric filters.


D. What Are the Control Costs?


    To estimate the national cost impacts of the proposed rule for 
existing sources, EPA developed several model boilers and process 
heaters and determined the cost of control equipment for these model 
boilers. The EPA assigned a model boiler or heater to each existing 
unit in the database based on the fuel, size, design, and current 
controls. The analysis considered all air pollution control equipment 
currently in operation at existing boilers and process heaters. Model 
costs were then assigned to all existing units that could not otherwise 
meet the proposed emission limits. The resulting total national cost 
impact of the proposed rule is 1,790 million dollars in capital 
expenditures and 860 million dollars per year in total annual costs. 
The total capital and annual costs include costs for testing, 
monitoring, and recordkeeping and reporting. Table 3 of this preamble 
shows the capital and annual cost impacts for each subcategory. Costs 
include testing and monitoring costs, but not recordkeeping and 
reporting costs.


                   Table 3.--Summary of Capital and Annual Costs for New and Existing Sources
----------------------------------------------------------------------------------------------------------------
                                                                            Estimated/
                                                                            projected    Annualized    Capital
                  Source                             Subcategory            number of       cost        costs
                                                                             affected    (10\6\ $/    (10\6\ $)
                                                                              units         yr)
----------------------------------------------------------------------------------------------------------------
Existing Units............................  Large solid units............        3,481          814        1,605
                                            Small solid units............          327            0            0
                                            Limited use solid units......          249           23          105
                                            Liquid units.................        7,251            0            0
                                            Gaseous units................       46,892            0            0


[[Page 1688]]




New Units.................................  Large solid units............          211           10           21
                                            Small solid units............           25            3            3
                                            Limited use solid units......           11            1            1
                                            Large liquid units...........           90            1            3
                                            Small liquid units...........          164            0            0
                                            Limited use liquid units.....           51          0.3            2
                                            Gaseous units................        3,463           11           51
----------------------------------------------------------------------------------------------------------------


    Using Department of Energy projections on fuel expenditures, the 
number of additional boilers that could be potentially constructed was 
estimated. The resulting total national cost impact of the proposed 
rule in the 5th year is 58 million dollars in capital expenditures and 
18.6 million dollars per year in total annual costs. Costs are mainly 
for testing and monitoring.
    A discussion of the methodology used to estimate cost impacts is 
presented in ``Methodology and Results of Estimating the Cost of 
Complying with the Industrial, Commercial, and Institutional Boiler and 
Process Heater NESHAP'' in the Docket.


E. Can We Achieve the Goals of the Proposed Rule in a Less Costly 
Manner?


    We have made every effort in developing this proposal to minimize 
the cost to the regulated community and allow maximum flexibility in 
compliance options consistent with our statutory obligations. We 
recognize, however, that the proposal may still require some facilities 
to take costly steps to further control emissions even though those 
emissions may not result in exposures which could pose an excess 
individual lifetime cancer risk greater than one in one million or 
which exceed thresholds determined to provide an ample margin of safety 
for protecting public health and the environment from the effects of 
hazardous air pollutants. We are, therefore, specifically soliciting 
comment on whether there are further ways to structure the proposed 
rule to focus on the facilities which pose significant risks and avoid 
the imposition of high costs on facilities that pose little risk to 
public health and the environment.
    Representatives of the plywood and composite wood products industry 
provided EPA with descriptions of three mechanisms that they believed 
could be used to implement more cost-effective reductions in risk. The 
docket for today's proposed rule contains white papers prepared by 
industry that outline their proposed approaches. These approaches could 
be effective in focusing regulatory controls on facilities that pose 
significant risks and avoiding the imposition of high costs on 
facilities that pose little risk to public health or the environment, 
and we are seeking public comment on the utility of each of these 
approaches with respect to this rule.
    One of the approaches, an applicability cutoff for threshold 
pollutants, would be implemented under the authority of CAA section 
112(d)(4); the second approach, subcategorization and delisting, would 
be implemented under the authority of CAA sections 112(c)(1) and 
112(c)(9); and, the third approach, would involve the use of a 
concentration-based applicability threshold. We are seeking comment on 
whether these approaches are legally justified and, if so, we ask for 
information that could be used to support such approaches.
    The maximum achievable control technology, or MACT, program 
outlined in CAA section 112(d) is intended to reduce emissions of HAP 
through the application of MACT to major sources of toxic air 
pollutants. Section 112(c)(9) of the CAA is intended to allow EPA to 
avoid setting MACT standards for categories or subcategories of sources 
that pose less than a specified level of risk to public health and the 
environment. The EPA requests comment on whether the proposals 
described here appropriately rely on these provisions of CAA section 
112. While both approaches focus on assessing the inhalation exposures 
of HAP emitted by a source, EPA specifically requests comment on the 
appropriateness and necessity of extending these approaches to account 
for non-inhalation exposures or to account for adverse environmental 
impacts. In addition to the specific requests for comment noted in this 
section, we are also interested in any information or comment 
concerning technical limitations, environmental and cost impacts, 
compliance assurance, legal rationale, and implementation relevant to 
the identified approaches. We also request comment on appropriate 
practicable and verifiable methods to ensure that sources' emissions 
remain below levels that protect public health and the environment. We 
will evaluate all comments before determining whether either of the 
three approaches will be included in the final rule.
1. Industry Emissions and Potential Health Effects
    To estimate the potential baseline risks posed by the Industrial 
Boiler and Process Heater source category, EPA performed a crude risk 
analysis of the source category that focused only on cancer risks. The 
results of the analysis are based on approaches for estimating cancer 
incidence that carry significant assumptions, uncertainties, and 
limitations. Based on the assessment, if the proposed rule is 
implemented at all facilities in the source category, cancer incidence 
in the U.S. may be reduced by as many as tens of cases per year. Due to 
the uncertainties associated with the analysis, this analysis should be 
regarded as one perspective on the estimate of annual cancer incidence 
reduction; the true risk reductions are unknown. (Details of this 
assessment are available in two memoranda in the docket: Memorandum on 
``Method for Approximate (``Top Down'') Estimates of Aggregate Cancer 
Risk Associated with Two Maximum Achievable Control Technology (MACT) 
Source Categories: Reciprocating Internal Combustion Engines (RICE) and 
Industrial/Commercial/Institutional Boilers'' and Memorandum on 
``Additional Perspectives on (``Top Down'') Estimates of Aggregate 
Cancer Risk Associated with Industrial/Commercial/Institutional 
Boilers''.)


[[Page 1689]]


2. Applicability Cutoffs for Threshold Pollutants Under Section 
112(d)(4) of the CAA
    The first approach is an applicability cutoff for threshold 
pollutants that is based on EPA's authority under CAA section 112(d)(4) 
to establish standards for HAP which are threshold pollutants. A 
threshold pollutant is one for which there is a concentration or dose 
below which adverse effects are not expected to occur over a lifetime 
of exposure. For such pollutants, CAA section 112(d)(4) allows EPA to 
consider the threshold level, with an ample margin of safety, when 
establishing emission standards. Specifically, CAA section 112(d)(4) 
allows EPA to establish emission standards that are not based upon the 
maximum achievable control technology specified under CAA section 
112(d)(2) for pollutants for which a health threshold has been 
established. Such standards may be less stringent than MACT. 
Historically, EPA has interpreted CAA section 112(d)(4) to allow 
categories of sources that emit only threshold pollutants to avoid 
further regulation if those emissions result in ambient levels that do 
not exceed the threshold, with an ample margin of safety.\2\
---------------------------------------------------------------------------


    \2\ See 63 FR 18754, 18765-66 (April 15, 1998) (Pulp and Paper 
Combustion Sources Proposal NESHAP).
---------------------------------------------------------------------------


    A different interpretation would allow us to exempt individual 
facilities within a source category that meet the CAA section 112(d)(4) 
requirements. There are three potential scenarios under this 
interpretation of the CAA section 112(d)(4) provision. One scenario 
would allow an exemption for individual facilities that emit only 
threshold pollutants and can demonstrate that their emissions of 
threshold pollutants would not result in air concentrations above the 
threshold levels, with an ample margin of safety, even if the category 
is otherwise subject to MACT. A second scenario would allow the CAA 
section 112(d)(4) provision to be applied to both threshold and 
nonthreshold pollutants, using the one in a million cancer risk level 
for decision making for nonthreshold pollutants.
    A third scenario would allow a CAA section 112(d)(4) exemption at a 
facility that emits both threshold and nonthreshold pollutants. For 
those emission points where only threshold pollutants are emitted and 
where emissions of the threshold pollutants would not result in air 
concentrations above the threshold levels, with an ample margin of 
safety, those emission points could be exempt from the MACT standard. 
The MACT standard would still apply to nonthreshold emissions from 
other emission points at the source. For this third scenario, emission 
points that emit a combination of threshold and nonthreshold pollutants 
that are co-controlled by MACT would still be subject to the MACT level 
of control. However, any threshold HAP eligible for exemption under CAA 
section 112(d)(4) that are controlled by control devices different from 
those controlling non-threshold HAP would be able to use the exemption, 
and the facility would still be subject to the parts of the standard 
that control nonthreshold pollutants or that control both threshold and 
nonthreshold pollutants.
    a. Estimation of hazard quotients and hazard indices. Under the CAA 
section 112(d)(4) approach, EPA would have to determine that emissions 
of each of the threshold pollutants emitted by industrial boiler and 
process heater sources at the facility do not result in exposures which 
exceed the threshold levels, with an ample margin of safety. The common 
approach for evaluating the potential hazard of a threshold air 
pollutant is to calculate a hazard quotient by dividing the pollutant's 
inhalation exposure concentration (often assumed to be equivalent to 
its estimated concentration in air at a location where people could be 
exposed) by the pollutant's inhalation Reference Concentration (RfC). 
An RfC is defined as an estimate (with uncertainty spanning perhaps an 
order of magnitude) of a continuous inhalation exposure that, over a 
lifetime, likely would not result in the occurrence of adverse health 
effects in humans, including sensitive individuals. The EPA typically 
establishes an RfC by applying uncertainty factors to the critical 
toxic effect derived from the lowest- or no-observed-adverse-effect 
level of a pollutant.\3\ A hazard quotient less than one means that the 
exposure concentration of the pollutant is less than the RfC, and, 
therefore, presumed to be without appreciable risk of adverse health 
effects. A hazard quotient greater than one means that the exposure 
concentration of the pollutant is greater than the RfC. Further, EPA 
guidance for assessing exposures to mixtures of threshold pollutants 
recommends calculating a hazard index (HI) by summing the individual 
hazard quotients for those pollutants in the mixture that affect the 
same target organ or system by the same mechanism.\4\ Hazard index 
values would be interpreted similarly to hazard quotients; values below 
one would generally be considered to be without appreciable risk of 
adverse health effects, and values above one would generally be cause 
for concern.
---------------------------------------------------------------------------


    \3\ ``Methods for Derivation of Inhalation Reference 
Concentrations and Applications of Inhalation Dosimetry.'' EPA-600/
8-90-066F, Office of Research and Development, USEPA, October 1994.
    \4\ ``Supplementary Guidance for Conducting Health Risk 
Assessment of Chemical Mixtures. Risk Assessment Forum Technical 
Panel,'' EPA/630/R-00/002. USEPA, August 2000. http://www.epa.gov/nceawww1/pdfs/chem
 mix/chem mix 08 2001.pdf.
---------------------------------------------------------------------------


    For the determinations discussed herein, EPA would generally plan 
to use RfC values contained in EPA's toxicology database, the 
Integrated Risk Information System (IRIS). When a pollutant does not 
have an approved RfC in IRIS, or when a pollutant is a carcinogen, EPA 
would have to determine whether a threshold exists based upon the 
availability of specific data on the pollutant's mode or mechanism of 
action, potentially using a health threshold value from an alternative 
source, such as the Agency for Toxic Substances and Disease Registry 
(ATSDR) or the California Environmental Protection Agency (CalEPA). 
Table 4 of this preamble provides RfC, as well as unit risk estimates, 
for the HAP emitted by facilities in the industrial boiler and process 
heater source category. A unit risk estimate is defined as the upper-
bound excess lifetime cancer risk estimated to result from continuous 
exposure to an agent at a concentration of 1 microgram per cubic meter 
([mu]g/m3) in air.


[[Page 1690]]






 Table 4.--Dose-Response Assessment Values for HAP Reported Emitted by the Industrial Boiler and Process Heater
                                                 Source Category
----------------------------------------------------------------------------------------------------------------
                                                    Reference concentration \a\     Unit risk estimate \b\  (1/
          Chemical name               CAS No.                (mg/m\3\)                    ([mu]g/m \3\))
----------------------------------------------------------------------------------------------------------------
Acetaldehyde....................         75-07-0  9.0E-IRIS 03                    2.2E-06 IRIS
Acrolein........................        107-02-8  2.0E-IRIS 05
Arsenic compounds...............       7440-38-2  3.0E-CAL 05                     4.3E-03 IRIS
Benzene.........................         71-43-2  6.0E-CAL 02                     7.8E-06 IRIS
Beryllium compounds.............       7440-41-7  2.0E-IRIS 05                    2.4E-03 IRIS
Cadmium compounds...............       7440-43-9  2.0E-CAL 05                     1.8E-03 IRIS
Chromium (VI) compounds.........      18540-29-9  1.0E-IRIS 04                    1.2E-02 IRIS
Dibenzofuran....................        132-64-9
Dibutylphthalate................         84-74-2
p-Dichlorobenzene...............        106-46-7  8.0E-IRIS 01                    1.1E-05 CAL
Ethyl benzene...................        100-41-4  1.0E+0 IRIS 0
Formaldehyde....................         50-00-0  9.8E-ATSDR 03                   1.3E-05 IRIS
Hydrochloric acid...............       7647-01-0  2.0E-IRIS 02
Hydrogen fluoride...............       7664-39-3  3.0E-P-CAL 02
Lead compounds..................       7439-92-1  1.5E-EPA 03 ORD                 1.2E-05 CAL
Manganese compounds.............       7439-96-5  5.0E-IRIS 05
Mercury compounds...............       HG--CMPDS  9.0E-CAL 05
Methyl chloroform...............         71-55-6  1.0E+0 CAL 0
Methyl ethyl ketone.............         78-93-3  1.0E+0 IRIS 0
Methylene chloride..............         75-09-2  1.0E+0 ATSDR 0                  4.7E-07 IRIS
Nickel compounds................       7440-02-0  2.0E-ATSDR 04
Nickel subsulfide...............      12035-72-2  ..............................  4.8E-04 IRIS
PAHs (shown below as 7-PAH)
Benzo (a) anthracene............         56-55-3  ..............................  1.1E-04 CAL
Benzo (b) fluoranthene..........        205-99-2  ..............................  1.1E-04 CAL
Benzo (k) fluoranthene..........        207-08-9  ..............................  1.1E-04 CAL
Benzo (a) pyrene................         50-32-8  ..............................  1.1E-03 CAL
Chrysene........................        218-01-9  ..............................  1.1E-05 CAL
Dibenz (a,h) anthracene.........         53-70-3  ..............................  1.2E-03 CAL
Indeno (1,2,3-cd) pyrene........        193-39-5  ..............................  1.4E-04 CAL
Phosphorus \c\
2,3,7,8-Tetrachlorodibenzo-p-          1746-01-6  4.0E-CAL 08                     3.3E+01 EPA ORD
 dioxin.
Toluene.........................        108-88-3  4.0E-IRIS 01
m-Xylene \c\....................        108-38-3
o-Xylene \c\....................         95-47-6
Xylenes (mixed).................       1330-20-7  4.3E-ATSDR 01
----------------------------------------------------------------------------------------------------------------
\a\ Reference Concentration: An estimate (with uncertainty spanning perhaps an order of magnitude) of a
  continuous inhalation exposure to the human population (including sensitive subgroups which include children,
  asthmatics and the elderly) that is likely to be without an appreciable risk of deleterious effects during a
  lifetime. It can be derived from various types of human or animal data, with uncertainty factors generally
  applied to reflect limitations of the data used.
\b\ Unit Risk Estimate: The upper-bound excess lifetime cancer risk estimated to result from continuous exposure
  to an agent at a concentration of 1 [mu]g/m \3\ in air. The interpretation of the Unit Risk Estimate would be
  as follows: if the Unit Risk Estimate = 1.5 x 10-6 per [mu]g/m \3\, 1.5 excess tumors are expected to develop
  per 1,000,000 people if exposed daily for a lifetime to 1 [mu]g of the chemical in 1 cubic meter of air. Unit
  Risk Estimates are considered upper bound estimates, meaning they represent a plausible upper limit to the
  true value. (Note that this is usually not a true statistical confidence limit.) The true risk is likely to be
  less, but could be greater.
\c\ No dose-response assessment is available.
Sources:
IRIS = EPA Integrated Risk Information System (http://www.epa.gov/iris/subst/index.html).
ATSDR = U.S. Agency for Toxic Substances and Disease Registry (http://www.atsdr.cdc.gov/mrls.html).
CAL = California Office of Environmental Health Hazard Assessment (http://www.oehha.ca.gov/air/hot_spots/
  index.html).


    To establish an applicability cutoff under CAA section 112(d)(4), 
EPA would need to define ambient air exposure concentration limits for 
any threshold pollutants involved. There are several factors to 
consider when establishing such concentrations. First, we would need to 
ensure that the concentrations that would be established would protect 
public health with an ample margin of safety. As discussed above, the 
approach EPA commonly uses when evaluating the potential hazard of a 
threshold air pollutant is to calculate the pollutant's hazard 
quotient, which is the exposure concentration divided by the RfC.
    EPA's ``Supplementary Guidance for Conducting Health Risk 
Assessment of Chemical Mixtures'' suggests that the noncancer health 
effects associated with a mixture of pollutants ideally are assessed by 
considering the pollutants' common mechanisms of toxicity. The guidance 
also suggests, however, that when exposures to mixtures of pollutants 
are being evaluated, the risk assessor may calculate a HI. The 
recommended method is to calculate multiple hazard indices for each 
exposure route of interest, and for a single specific toxic effect or 
toxicity to a single target organ. The default approach recommended by 
the guidance is to sum the hazard quotients for those pollutants that 
induce the same toxic effect or affect the same target organ. A mixture 
is then assessed by several HI, each representing one toxic effect or 
target organ. The guidance notes that the pollutants included in the HI 
calculation are any pollutants that show the effect being assessed, 
regardless of the critical effect upon which the RfC is based. The 
guidance cautions that if the


[[Page 1691]]


target organ or toxic effect for which the HI is calculated is 
different from the RfC's critical effect, then the RfC for that 
chemical will be an overestimate, that is, the resultant HI potentially 
may be overprotective. Conversely, since the calculation of an HI does 
not account for the fact that the potency of a mixture of HAP can be 
more potent than the sum of the individual HAP potencies, an HI may 
potentially be underprotective in some situations.
    b. Options for establishing a hazard index limit. One consideration 
in establishing a hazard index limit is whether the analysis considers 
the total ambient air concentrations of all the emitted HAP to which 
the public is exposed.\5\ There are at least several options for 
establishing a hazard index limit for the CAA section 112(d)(4) 
analysis that reflect, to varying degrees, public exposure.
---------------------------------------------------------------------------


    \5\ Senate Debate on Conference Report (October 27, 1990), 
reprinted in ``A Legislative History of the Clean Air Act Amendments 
of 1990,'' Comm. Print S. Prt. 103-38 (1993) (``Legis. Hist.'') at 
868.
---------------------------------------------------------------------------


    One option is to allow the hazard index posed by all threshold HAP 
emitted from sources at the facility to be no greater than one. This 
approach is protective if no additional threshold HAP exposures would 
be anticipated from other sources in the vicinity of the facility or 
through other routes of exposure (e.g., through ingestion).
    A second option is to adopt a default percentage approach, whereby 
the hazard index limit of the HAP emitted by the facility is set at 
some percentage of one (e.g., 20 percent or 0.2). This approach 
recognizes the fact that the facility in question is only one of many 
sources of threshold HAP to which people are typically exposed every 
day. Because noncancer risk assessment is predicated on total exposure 
or dose, and because risk assessments focus only on an individual 
source, establishing a hazard index limit of 0.2 would account for an 
assumption that 20 percent of an individual's total exposure is from 
that individual source. For the purposes of this discussion, we will 
call all sources of HAP, other than the facility in question, 
background sources. If the facility is allowed to emit HAP such that 
its own impacts could result in HI values of one, total exposures to 
threshold HAP in the vicinity of the facility could be substantially 
greater than one due to background sources, and this would not be 
protective of public health, since only HI values below one are 
considered to be without appreciable risk of adverse health effects. 
Thus, setting the hazard index limit for the facility at some default 
percentage of one will provide a buffer which would help to ensure that 
total exposures to threshold HAP near the facility (i.e., in 
combination with exposures due to background sources) will generally 
not exceed one, and can generally be considered to be without 
appreciable risk of adverse health effects.
    The EPA requests comment on using the default percentage approach 
and on setting the default hazard index limit at 0.2. The EPA is also 
requesting comment on whether an alternative HI limit, in some multiple 
of one would be a more appropriate applicability cutoff.
    A third option is to use available data (from scientific literature 
or EPA studies, for example) to determine background concentrations of 
HAP, possibly on a national or regional basis. These data would be used 
to estimate the exposures to HAP from non-industrial boiler and process 
heater sources in the vicinity of an individual facility. For example, 
the EPA's National-scale Air Toxics Assessment (NATA) \6\ and ATSDR's 
Toxicological Profiles \7\ contain information about background 
concentrations of some HAP in the atmosphere and other media. The 
combined exposures from these sources and from other sources (as 
determined from the literature or studies) would then not be allowed to 
exceed a hazard index limit of one. The EPA requests comment on the 
appropriateness of setting the hazard index limit at one for such an 
analysis.
---------------------------------------------------------------------------


    \6\ See http://www.epa.gov/ttn/atw/nata.
    \7\ See http://www.atsdr.cdc.gov/toxpro2.html.
---------------------------------------------------------------------------


    A fourth option is to allow facilities to estimate or measure their 
own facility-specific background HAP concentrations for use in their 
analysis. With regard to the third and fourth options, the EPA requests 
comment on how these analyses could be structured. Specifically, EPA 
requests comment on how the analyses should take into account 
background exposure levels from air, water, food and soil encountered 
by the individuals exposed to emissions from industrial boilers and 
process heaters. In addition, we request comment on how such analyses 
should account for potential increases in exposures due to the use of 
new HAP or the increased use of a previously emitted HAP, or the effect 
of other nearby sources that release HAP.
    EPA requests comment on the feasibility and scientific validity of 
each of these or other approaches. Finally, EPA requests comment on how 
we should implement the CAA section 112(d)(4) applicability cutoffs, 
including appropriate mechanisms for applying cutoffs to individual 
facilities. For example, would the title V permit process provide an 
appropriate mechanism?
    c. Tiered analytical approach for predicting exposure. Establishing 
that a facility meets the cutoffs established under CAA section 
112(d)(4) will necessarily involve combining estimates of pollutant 
emissions with air dispersion modeling to predict exposures. The EPA 
envisions that we would promote a tiered analytical approach for these 
determinations. A tiered analysis involves making successive 
refinements in modeling methodologies and input data to derive 
successively less conservative, more realistic estimates of pollutant 
concentrations in air and estimates of risk.
    As a first tier of analysis, EPA could develop a series of simple 
look-up tables based on the results of air dispersion modeling 
conducted using conservative input assumptions. By specifying a limited 
number of input parameters, such as stack height, distance to property 
line, and emission rate, a facility could use these look-up tables to 
determine easily whether the emissions from their sources might cause a 
hazard index limit to be exceeded.
    A facility that does not pass this initial conservative screening 
analysis could implement increasingly more site-specific but more 
resource-intensive tiers of analysis using EPA-approved modeling 
procedures, in an attempt to demonstrate that exposure to emissions 
from the facility does not exceed the hazard index limit. The EPA's 
guidance could provide the basis for conducting such a tiered 
analysis.\8\
---------------------------------------------------------------------------


    \8\ ``A Tiered Modeling Approach for Assessing the Risks due to 
Sources of Hazardous Air Pollutants.'' EPA-450/4-92-001. David E. 
Guinnup, Office of Air Quality Planning and Standards, USEPA, March 
1992.
---------------------------------------------------------------------------


    The EPA requests comment on methods for constructing and 
implementing a tiered analytical approach for determining applicability 
of the CAA section 112(d)(4) criterion to specific industrial boiler 
and process heater sources. It is also possible that ambient monitoring 
data could be used to supplement or supplant the tiered modeling 
approach described above. It is envisioned that the appropriate 
monitoring to support such a determination could be extensive. The EPA 
requests comment on the appropriate use of monitoring in the 
determinations described above.
    d. Accounting for dose-response relationships. In the past, EPA 
routinely treated carcinogens as nonthreshold pollutants. The EPA 
recognizes that


[[Page 1692]]


advances in risk assessment science and policy may affect the way EPA 
differentiates between threshold and nonthreshold HAP. The EPA's draft 
Guidelines for Carcinogen Risk Assessment \9\ suggest that carcinogens 
be assigned non-linear dose-response relationships where data warrant. 
Moreover, it is possible that dose-response curves for some pollutants 
may reach zero risk at a dose greater than zero, creating a threshold 
for carcinogenic effects. It is possible that future evaluations of the 
carcinogens emitted by this source category would determine that one or 
more of the carcinogens in the category is a threshold carcinogen or is 
a carcinogen that exhibits a non-linear dose-response relationship but 
does not have a threshold.
---------------------------------------------------------------------------


    \9\ ``Draft Revised Guidelines for Carcinogen Risk Assessment.'' 
NCEA-F-0644. USEPA, Risk Assessment Forum, July 1999. pp 3-9ff. 
http://www.epa.gov/ncea/raf/pdfs/cancer_gls.pdf.
---------------------------------------------------------------------------


    The dose-response assessments for formaldehyde and acetaldehyde are 
currently undergoing revision by the EPA. As part of this revision 
effort, EPA is evaluating formaldehyde and acetaldehyde as potential 
non-linear carcinogens. The revised dose-response assessments will be 
subject to review by the EPA Science Advisory Board, followed by full 
consensus review, before adoption into the EPA Integrated Risk 
Information System. At this time, EPA estimates that the consensus 
review will be completed by the end of 2003. The revision of the dose-
response assessments could affect the potency factors of these HAP, as 
well as their status as threshold or nonthreshold pollutants. At this 
time, the outcome is not known. In addition to the current reassessment 
by EPA, there have been several reassessments of the toxicity and 
carcinogenicity of formaldehyde in recent years, including work by the 
World Health Organization and the Canadian Ministry of Health.
    The EPA requests comment on how we should consider the state of the 
science as it relates to the treatment of threshold pollutants when 
making determinations under CAA section 112(d)(4). In addition, EPA 
requests comment on whether there is a level of emissions of a 
nonthreshold carcinogenic HAP (e.g., benzene, methylene chloride) at 
which it would be appropriate to allow a facility to use the approaches 
discussed in this section.
    If the CAA section 112(d)(4) approach were adopted, the proposed 
rulemaking would likely indicate that the requirements of the rule do 
not apply to any source that demonstrates, based on a tiered approach 
that includes EPA-approved modeling of the affected source's emissions, 
that the anticipated HAP exposures do not exceed the specified hazard 
index limit.
3. Applicability Cutoffs From Hydrogen Chloride Controls Under CAA 
Section 112(d)(4) of the CAA
    This approach is an applicability cutoff for the threshold 
pollutant hydrogen chloride that is based on EPA's authority under CAA 
section 112(d)(4). Industry's suggested approach interprets this 
provision to allow EPA to exempt, from the hydrogen chloride controls, 
individual facilities that can demonstrate that their emissions of 
hydrogen chloride will not result in air concentrations above the 
inhalation reference concentration for hydrogen chloride, even if the 
category is otherwise subject to MACT.
    If this approach were adopted, the proposed rulemaking would likely 
indicate that the requirements of the rule pertaining to hydrochloric 
acid do not apply to any source that demonstrates, based on EPA-
approved modeling of the affected source's emissions, that the 
anticipated hydrochloric acid exposures do not exceed the inhalation 
reference concentration for hydrochloric acid.
4. Subcategory Delisting Under Section 112(c)(9)(B) of the CAA
    The EPA is authorized to establish categories and subcategories of 
sources, as appropriate, pursuant to CAA section 112(c)(1), in order to 
facilitate the development of MACT standards consistent with section 
112 of the CAA. Further, CAA section 112(c)(9)(B) allows EPA to delete 
a category (or subcategory) from the list of major sources for which 
MACT standards are to be developed when the following can be 
demonstrated: (1) In the case of carcinogenic pollutants, that ``no 
source in the category * * * emits (carcinogenic) air pollutants in 
quantities which may cause a lifetime risk of cancer greater than one 
in one million to the individual in the population who is most exposed 
to emissions of such pollutants from the source''; (2) in the case of 
pollutants that cause adverse noncancer health effects, that 
``emissions from no source in the category or subcategory * * * exceed 
a level which is adequate to protect public health with an ample margin 
of safety''; and (3) in the case of pollutants that cause adverse 
environmental effects, that ``no adverse environmental effect will 
result from emissions from any source.''
    Given these authorities and the suggestions from the white paper 
prepared by industry representatives (see docket number OAR-2002-0058), 
EPA is considering whether it would be possible to establish a 
subcategory of facilities within the larger industrial boiler and 
process heater source category that would meet the risk-based criteria 
for delisting. Such criteria would likely include the same requirements 
as described previously for the second scenario under the CAA section 
112(d)(4) approach, whereby a facility would be in the low-risk 
subcategory if its emissions of threshold pollutants do not result in 
exposures which exceed the HI limits and if its emissions of 
nonthreshold pollutants do not result in exposures which exceed a 
cancer risk level of 10-6. The EPA requests comment on what 
an appropriate HI limit would be for a determination that a facility be 
included in the low-risk subcategory.
    Since each facility in such a subcategory would be a low-risk 
facility (i.e., if each met these criteria), the subcategory could be 
delisted in accordance with CAA section 112(c)(9), thereby limiting the 
costs and impacts of the proposed rule to only those facilities that do 
not qualify for subcategorization and delisting.
    Facilities seeking to be included in the delisted subcategory would 
be responsible for providing all data required to determine whether 
they are eligible for inclusion. Facilities that could not demonstrate 
that they are eligible to be included in the low-risk subcategory would 
be subject to MACT and possible future residual risk standards. The EPA 
solicits comment on implementing a risk-based approach for establishing 
subcategories of industrial boiler and process heater facilities.
    Establishing that a facility qualifies for the low-risk subcategory 
under CAA section 112(c)(9) will necessarily involve combining 
estimates of pollutant emissions with air dispersion modeling to 
predict exposures. The EPA envisions that we would employ the same 
tiered analytical approach described earlier in the CAA section 
112(d)(4) discussion for these determinations.
    One concern that EPA has with respect to this CAA section 112(c)(9) 
approach is the effect that it could have on the MACT floors. If many 
of the facilities in the low-risk subcategory are well-controlled, that 
could make the MACT floor less stringent for the remaining facilities. 
One approach that has been suggested to mitigate this effect would be 
to establish the MACT floor now based on controls in place for the


[[Page 1693]]


entire category and to allow facilities to become part of the low-risk 
subcategory in the future, after the MACT based standards are 
established. This would allow low risk facilities to use the CAA 
section 112(c)(9) exemption without affecting the MACT floor 
calculation. The EPA requests comment on this suggested approach.
    Another approach under CAA section 112(c)(9) would be to define a 
subcategory of facilities within the industrial boiler and process 
heater source category based upon technological differences, such as 
differences in production rate, emission vent flow-rates, overall 
facility size, emissions characteristics, processes, or air pollution 
control device viability. The EPA requests comment on how we might 
establish industrial boiler and process heater subcategories based on 
these, or other, source characteristics. If it could then be determined 
that each source in this technologically-defined subcategory presents a 
low risk to the surrounding community, the subcategory could then be 
delisted in accordance with CAA section 112(c)(9). The EPA requests 
comment on the concept of identifying technologically-based 
subcategories that may include only low-risk facilities within this 
source category.
    If this CAA section 112(c)(9) approach were adopted, the rulemaking 
would likely indicate that the rule does not apply to any source that 
demonstrates that it belongs in a subcategory which has been delisted 
under CAA section 112(c)(9).


F. What Are the Economic Impacts?


    The economic impact analysis shows that the expected price increase 
for output in the 40 affected industries would be no more than 0.04 
percent as a result of the proposed rule for industrial boilers and 
process heaters. The expected change in production of affected output 
is a reduction of only 0.03 percent or less in the same industries. In 
addition, impacts to affected energy markets show that prices of 
petroleum, natural gas, electricity and coal should increase by no more 
than 0.05 percent as a result of implementation of the proposed rule, 
and output of these types of energy should decrease by no more than 
0.01 percent. Therefore, it is likely that there is no adverse impact 
expected to occur for those industries that produce output affected by 
the proposed rule, such as lumber and wood products, chemical 
manufacturers, petroleum refining, and furniture manufacturing.


G. What Are the Social Costs and Benefits of the Proposed Rule?


    Our assessment of costs and benefits of the proposed rule is 
detailed in the ``Regulatory Impact Analysis for the Proposed 
Industrial, Commercial, and Institutional Boilers and Process Heaters 
MACT.'' The Regulatory Impact Analysis (RIA) is located in the Docket.
    It is estimated that 3 years after implementation of the proposed 
requirements, HAP would be reduced by 58,500 tons/yr (53,200 megagrams 
per year (Mg/yr)) due to reductions in hydrochloric acid, arsenic, 
mercury, hydrofluoric acid, and several other HAP from existing 
affected emission sources. Of these reductions, 42,000 tons/yr (38,200 
Mg/yr) are of hydrochloric acid. In addition to these reductions, there 
are 73 tons/yr (66 Mg/yr) of HAP reductions expected from new sources. 
Of these reductions, virtually all of them are of hydrochloric acid. 
The health effects associated with these HAP are discussed earlier in 
this preamble. While it is beneficial to society to reduce these HAP, 
we are unable to quantify and provide a monetized estimate of the 
benefits at this time.
    Despite our inability to quantify and provide monetized benefit 
estimates from HAP reductions, it is possible to derive rough estimates 
for one of the more important benefit categories, i.e., the potential 
number of cancer cases avoided and cancer risk reduced as a result of 
the imposition of the MACT level of control on this source category. 
Our analysis suggests that imposition of the MACT level of control 
would reduce cancer cases by possibly tens of cases per year, on 
average, starting some years after implementation of the standard. This 
risk reduction estimate is uncertain and should be regarded as an 
extremely rough estimate, and should be viewed in the context of the 
full spectrum of unquantified noncancer effects associated with the HAP 
reductions. Noncancer effects associated with the HAP are presented 
earlier in this preamble.
    The control technologies used to reduce the level of HAP emitted 
from affected sources are also expected to reduce emissions of PM 
(PM10, PM2.5), and sulfur dioxide 
(SO2). It is estimated that PM10 emissions 
reductions total approximately 562,000 tons/yr (510,000 Mg/yr), 
PM2.5 emissions reductions total approximately 159,000 tons/
yr (145,000 Mg/yr), and SO2 emissions reductions total 
approximately 102,670 Mg/yr (113,000 tons/yr). These estimated 
reductions occur from existing sources in operation 3 years after the 
implementation of the requirements of the proposed rule and are 
expected to continue throughout the life of the sources.
    Human health effects associated with exposure to PM10 
and PM2.5 include premature mortality (short-term exposure 
to PM10 and long-term exposure to PM2.5), chronic 
bronchitis, additional hospital admissions from respiratory and 
cardiovascular causes, acute respiratory symptoms, and other effects. 
Welfare effects associated with PM10 and PM2.5 
emissions include impaired recreational and residential visibility, 
household soiling, and materials damage. As SO2 emissions 
transform into PM, they can lead to the same health and welfare effects 
listed above.
    For PM10 and PM2.5, we did provide a monetary 
estimate for the benefits associated with the reduction of the 
emissions, and we have conducted several analyses recently that 
estimate the monetized benefits of PM reductions, including: the RIA of 
the PM/Ozone national ambient air quality standards (NAAQS) (1997), the 
Nitrogen Oxide (NOX) State Implementation Plan (SIP) Call 
(1998), the CAA section 126 RIA (1999), a study conducted for section 
812(b) of the CAA (1999), the Tier 2/Gasoline Sulfur Standards (1999), 
and the Heavy Duty Engine/Diesel Fuel Standards (2000).
    On September 26, 2002, the National Academy of Sciences (NAS) 
released a report on its review of the Agency's methodology for 
analyzing the health benefits of measures taken to reduce air 
pollution. The report focused on EPA's approach for estimating the 
health benefits of regulations designed to reduce concentrations of 
airborne particulate matter (PM).
    In its report, the NAS said that EPA has generally used a 
reasonable framework for analyzing the health benefits of PM-control 
measures. It recommended, however, that the Agency take a number of 
steps to improve its benefits analysis. In particular, the NAS stated 
that the Agency should:


--Include benefits estimates for a range of regulatory options;
--Estimate benefits for intervals, such as every 5 years, rather than a 
single year;
--Clearly state the projected baseline statistics used in estimating 
health benefits, including those for air emissions, air quality, and 
health outcomes;
--Examine whether implementation of proposed regulations might cause 
unintended impacts on human health or the environment;


[[Page 1694]]


--When appropriate, use data from non-U.S. studies to broaden age 
ranges to which current estimates apply and to include more types of 
relevant health outcomes; and
--Begin to move the assessment of uncertainties from its ancillary 
analyses into its primary analyses by conducting probabilistic, 
multiple-source uncertainty analyses. This assessment should be based 
on available data and expert judgment.


    Although the NAS made a number of recommendations for improvement 
in EPA's approach, it found that the studies selected by EPA for use in 
its benefits analysis were generally reasonable choices. In particular, 
the NAS agreed with EPA's decision to use cohort studies to derive 
benefits estimates. It also concluded that the Agency's selection of 
the American Cancer Society (ACS) study for the evaluation of PM-
related premature mortality was reasonable, although it noted the 
publication of new cohort studies that should be evaluated by the 
Agency.
    Several of the NAS recommendations addressed the issue of 
uncertainty and how the Agency can better analyze and communicate the 
uncertainties associated with its benefits assessments. In particular, 
the Committee expressed concern about the Agency's reliance on a single 
value from its analysis and suggested that EPA develop a probabilistic 
approach for analyzing the health benefits of proposed regulatory 
actions. The Agency agrees with this suggestion and is working to 
develop such an approach for use in future rulemakings.
    In this benefits analysis for the proposed rule, the Agency has 
used an interim approach that shows the impact of several important 
alternative assumptions about the estimation and valuation of 
reductions in premature mortality and chronic bronchitis. This 
approach, which was developed in the context of the Agency's Clear 
Skies analysis, provides an alternative estimate of health benefits 
using the time series studies in place of cohort studies, as well as 
alternative valuation methods for mortality and chronic bronchitis risk 
reductions.
    For the proposed rule, we conducted an air quality assessment to 
determine the change in ambient concentrations of PM10 and 
PM2.5 that result from reductions of PM and SO2 
at existing affected facilities. Our air quality analysis was conducted 
using the source-receptor (S-R) matrix model, a model that provides 
changes in PM10 and PM2.5 concentrations based on 
changes in PM and/or PM precursor emissions. Unfortunately, our data is 
not able to define the exact location of the reductions for every 
affected boiler and process heater. The air quality analysis was 
conducted for emissions reductions from those emissions sources that 
have a known link to a specific control device, which represents 
approximately 50 percent of the total emissions reductions mentioned 
above. Using this subset of information, we utilized the S-R matrix to 
determined the air quality change nationwide. The results of the air 
quality assessment served as input to a model that estimates the total 
monetary value of benefits of the health effects listed above. Total 
benefits associated with this portion of the analysis are $8.2 billion 
in the year 2005 (presented in 1999 dollars).
    For those emissions reductions from affected sources that do not 
have a known link to a specific control device, the results of the air 
quality analysis serve as a reasonable approximation of air quality 
changes to transfer to the remaining emissions reductions of the 
proposed rule. Because there is not a reasonable way to apportion the 
total benefits of the combined impact of the PM and SO2 
reductions from the air quality and benefit analyses completed above, 
we performed two additional S-R matrix analyses. One analysis was 
performed to evaluate the impact on air quality of the PM reductions 
alone (holding SO2 unchanged), and one to evaluate the 
impact on air quality from the SO2 reductions alone (holding 
PM unchanged). With independent PM and SO2 air quality 
assessments, we can determine the total benefit associated with each 
component of total pollutant reductions. The total benefit associated 
with the PM and SO2 reductions with unspecified location are 
$7.9 billion.
    Every benefit-cost analysis examining the potential effects of a 
change in environmental protection requirements is limited to some 
extent by data gaps, limitations in model capabilities (such as 
geographic coverage), and uncertainties in the underlying scientific 
and economic studies used to configure the benefit and cost models. 
Deficiencies in the scientific literature often result in the inability 
to estimate changes in health and environmental effects, such as 
potential increases in premature mortality associated with increased 
exposure to carbon monoxide. Deficiencies in the economics literature 
often result in the inability to assign economic values even to those 
health and environmental outcomes which can be quantified. While these 
general uncertainties in the underlying scientific and economics 
literatures are discussed in detail in the RIA and its supporting 
documents and references, the key uncertainties which have a bearing on 
the results of the benefit-cost analysis of today's action are the 
following:
    1. The exclusion of potentially significant benefit categories 
(e.g., health and ecological benefits of reduction in hazardous air 
pollutants emissions);
    2. Errors in measurement and projection for variables such as 
population growth;
    3. Uncertainties in the estimation of future year emissions 
inventories and air quality;
    4. Uncertainties associated with the extrapolation of air quality 
monitoring data to some unmonitored areas required to better capture 
the effects of the standards on the affected population;
    5. Variability in the estimated relationships of health and welfare 
effects to changes in pollutant concentrations; and
    6. Uncertainties associated with the benefit transfer approach.
    Despite these uncertainties, we believe the benefit-cost analysis 
provides a reasonable indication of the expected economic benefits of 
the industrial boilers and process heaters MACT under two different 
sets of assumptions.
    We have used two approaches (base and alternative estimates) to 
provide benefits in health effects and in monetary terms. They differ 
in the method used to estimate and value reduced incidences of 
mortality and chronic bronchitis, which is explained in detail in the 
RIA. While there is a substantial difference in the specific estimates, 
both approaches show that the industrial boilers and process heaters 
MACT may provide benefits to public health, whether expressed as health 
improvements or as economic benefits. These include prolonging lives, 
reducing cases of chronic bronchitis and hospital admissions, and 
reducing thousands of cases in other indicators of adverse health 
effects, such as work loss days, restricted activity days, and days 
with asthma attacks. In addition, there are a number of health and 
environmental effects which we were unable to quantify or monetize. 
These effects, denoted by ``B'' are additive to the both the base and 
alternative estimates of benefits. Results also reflect the use of two 
different discount rates for the valuation of reduced incidences of 
mortality; a 3 percent rate which is recommended by EPA's Guidelines 
for Preparing Economic Analyses (U.S.


[[Page 1695]]


EPA, 2000a), and 7 percent which is recommended by OMB Circular A-94 
(OMB, 1992).
    More specifically, the base estimate of benefits reflects the use 
of peer-reviewed methodologies developed for earlier risk and benefit-
cost assessments related to the Clean Air Act, such as the regulatory 
assessments of the Heavy Duty Diesel and Tier II rules and the section 
812 Report to Congress. The alternative estimate explores important 
aspects of the key elements underlying estimates of the benefits of 
reducing PM and SO2 emissions, specifically focusing on 
estimation and valuation of mortality risk reduction and valuation of 
chronic bronchitis. The alternative estimate of mortality reduction 
relies on recent scientific studies finding an association between 
increased mortality and short-term exposure to particulate matter over 
days to weeks, while the base estimate relies on a recent reanalysis of 
earlier studies that associate long-term exposure to fine particles 
with increased mortality. The alternative estimate differs in the 
following ways: it explicitly omits any impact of long-term exposure on 
premature mortality, it uses different data on valuation and makes 
adjustments relating to the health status and potential longevity of 
the populations most likely affected by PM, it also uses a cost-of-
illness method to value reductions in cases of chronic bronchitis while 
the base estimate is based on individual's willingness to pay (WTP) to 
avoid a case of chronic bronchitis. In addition, one key area of 
uncertainty is the value of a statistical life (VSL) for risk 
reductions in mortality, which is also the category of benefits that 
accounts for a large portion of the total benefit estimate. The 
adoption of a value for the projected reduction in the risk of 
premature mortality is the subject of continuing discussion within the 
economic and public policy analysis community. There is general 
agreement that the value to an individual of a reduction in mortality 
risk can vary based on several factors, including the age of the 
individual, the type of risk, the level of control the individual has 
over the risk, the individual's attitude toward risk, and the health 
status of the individual.
    The Environmental Economics Advisory Committee (EEAC) of the EPA 
Science Advisory Board (SAB) recently issued an advisory report which 
states that ``the theoretically appropriate method is to calculate 
willingness to pay for individuals whose ages correspond to those of 
the affected population, and that it is preferable to base these 
calculations on empirical estimates of WTP by age.'' (EPA-SAB-EEAC-00-
013). In developing our base estimate of the benefits of premature 
mortality reductions, we have appropriately discounted over the lag 
period between exposure and premature mortality. However, the empirical 
basis for adjusting the current $6 million VSL for other factors does 
not yet justify including these in our base estimate. A discussion of 
these factors is contained in the RIA and supporting documents. The EPA 
recognizes the need for additional research by the scientific community 
to develop additional empirical support for adjustments to VSL for the 
factors mentioned above. Furthermore, EPA prefers not to draw 
distinctions in the monetary value assigned to the lives saved even if 
they differ in age, health status, socioeconomic status, gender or 
other characteristic of the adult population.
    Given the advice from the SAB, we employed the suggested approach 
for the benefit analysis of the Heavy Duty Engine/Diesel Fuel standards 
conducted in 2000 to the Industrial, Commercial, and Institutional 
Boiler and Process Heater MACT discussed in this preamble. A full 
discussion of considerations made in our presentation of benefits is 
summarized in the preamble of the Final Heavy Duty Diesel Program 
issued in December 2000, and in all supporting documentation and 
analyses of the Heavy Duty Diesel Program, and in the RIA for the 
proposed rulemaking.
    In addition to the presentation of mortality valuation, our 
estimate also includes a ``B'' to represent those additional health and 
environmental benefits which could not be expressed in quantitative 
incidence and/or economic value terms. A full listing of the benefit 
categories that could not be quantified or monetized in our estimate 
are provided in the RIA for the proposed rule. A full appreciation of 
the overall economic consequences of the proposed industrial boiler and 
process heater standards requires consideration of all benefits and 
costs expected to result from today's proposed rule, not just those 
benefits and costs which could be expressed here in dollar terms. A 
full listing of the benefit categories that could not be quantified or 
monetized in our estimate are provided in Table 5 of this preamble.


                Table 5.--Unquantified Benefit Categories
------------------------------------------------------------------------
                                                           Unquantified
                                 Unquantified benefit        benefit
                                categories associated       categories
                                       with HAP          associated with
                                                                PM
------------------------------------------------------------------------
Health Categories...........  Airway responsiveness      Changes in
                              Pulmonary inflammation      pulmonary
                              Increased susceptibility    function.
                               to respiratory infection  Morphological
                              Acute inflammation and      changes.
                               respiratory cell damage    Altered host
                              Chronic respiratory         defense
                               damage/Premature aging     mechanisms.
                               of lungs                  Cancer.
                              Emergency room visits for  Other chronic
                               asthma                     respiratory
                                                          disease.
                                                         Emergency room
                                                          visits for
                                                          asthma.
                                                         Emergency room
                                                          visits for non-
                                                          asthma
                                                          respiratory
                                                          and
                                                          cardiovascular
                                                          causes.
                                                         Lower and upper
                                                          respiratory
                                                          symptoms.
                                                         Acute
                                                          bronchitis.
                                                         Shortness of
                                                          breath.
                                                         Increased
                                                          school absence
                                                          rates.
Welfare Categories..........  Ecosystem and vegetation   Materials
                               effects                    damage.
                              Damage to urban            Damage to
                               ornamentals (e.g.,         ecosystems
                               grass, flowers, shrubs,    (e.g., acid
                               and trees in urban         sulfate
                               areas)                     deposition).
                              Commercial field crops     Nitrates in
                              Fruit and vegetable crops   drinking
                              Reduced yields of tree      water.
                               seedlings, commercial     Visibility in
                               and non- commercial        recreational
                               forests                    and
                              Damage to ecosystems        residential
                              Materials damage            areas.
------------------------------------------------------------------------




[[Page 1696]]


    In summary, the base estimate using the VSL approach yields a total 
monetized benefit estimate of $16.1 billion + B (1999 dollars) in 2005 
when using a 3 percent interest rate (or approximately $15.4 billion + 
B when using a 7 percent interest rate). The alternative estimate 
totals approximately $2.4 billion + B when using a 3 percent interest 
rate (or approximately $2.6 billion + B when using a 7 percent interest 
rate).
    Using the results of the benefit analysis, we can use benefit-cost 
comparison (or net benefits) as another tool to evaluate the 
reallocation of society's resources needed to address the pollution 
externality created by the operation of industrial boilers and process 
heaters. The additional costs of internalizing the pollution produced 
at major sources of emissions from industrial boilers and process 
heaters are compared to the improvement in society's well-being from a 
cleaner and healthier environment. Comparing benefits of the proposed 
rule to the costs imposed by alternative ways to control emissions 
optimally identifies a strategy that results in the highest net benefit 
to society. In the case of the proposed rule, we are proposing only one 
option, the minimal level of control mandated by the CAA, or the MACT 
floor. Other alternatives that lead to higher levels of control (or 
beyond-the-floor alternatives) lead to higher estimates of benefits net 
of costs, but also lead to additional economic impacts including more 
substantial impacts to small entities. For more details, please refer 
to the RIA for the proposed rule.
    Table 6 of this preamble presents a summary of costs, benefits, and 
net benefits (i.e., benefits minus costs). Based on estimated 
compliance costs associated with the proposed rule and the predicted 
change in prices and production in the affected industries, the 
estimated social costs of the proposed rule are $780 million (1999 
dollars). Social costs are different from compliance costs in that 
social costs take into account the interactions between affected 
producers and the consumers of affected products in response to the 
imposition of the compliance costs.
    Therefore, the Agency's base estimate of monetized benefits net of 
costs is $15.2 billion + B (1999 dollars) in 2005 when using a 3 
percent discount rate (or approximately $15 billion + B when using a 7 
percent discount rate). However, using the more conservative 
alternative estimate of benefits, net benefits are $1.5 billion + B 
(1999 dollars) under a 3 percent discount rate (or approximately $1.7 
billion + B when using a 7 percent discount rate).
    In both cases, net benefits would be greater if all the benefits of 
the HAP and other pollutant reductions could be quantified. Notable 
omissions to the net benefits include all benefits of HAP reductions, 
including reduced cancer incidences, toxic morbidity effects, and 
cardiovascular and CNS effects. It is also important to note that not 
all benefits of SO2 and PM reductions have been monetized.


   Table 6.--Annual Net Benefits of the Industrial Boilers and Process
                        Heaters NESHAP in 2005 A
------------------------------------------------------------------------
                                                       Beyond the MACT
                                     MACT floor        floor  (million
                                   (million 1999$)          1999$)
------------------------------------------------------------------------
Social Costs B.................  $837..............  $1,923
Social Benefits: B, C, D
    HAP-related health and       Not monetized.....  Not monetized.
     welfare benefits.
    PM-related welfare benefits  Not monetized.....  Not monetized.
SO2- and PM-related health
 benefits:
    Primary Estimate
    --Using 3% Discount Rate...  $16,300 + B.......   $17,230 + B.
    Using 7% Discount Rate.....  $15,430 + B.......  $16,310 + B.
    Alternative Estimate
    --Using 3% Discount Rate...  $2,350 + B........  $2,380 + B.
    --Using 7% Discount Rate...  $2,585 + B........  $2,620 + B.
Net Benefits (Benefits -Costs):
 C, D
    Primary Estimate
    --Using 3% Discount Rate...  $15,465...........  $15,305 + B.
    --Using 7% Discount Rate...  $14,595...........  $14,385 + B.
    Alternative Estimate
    --Using 3% Discount Rate...  $1,515............  $455 + B.
    --Using 7% Discount Rate...  $1,750............  $700 + B.
------------------------------------------------------------------------
A All costs and benefits are rounded to the nearest $5 million. Thus,
  figures presented in this table may not exactly equal benefit and cost
  numbers presented in earlier sections of the chapter.
B Note that costs are the total costs of reducing all pollutants,
  including HAP as well as SO2 and PM10. Benefits in this table are
  associated only with PM and SO2 reductions.
C Not all possible benefits or disbenefits are quantified and monetized
  in this analysis. Potential benefit categories that have not been
  quantified and monetized are listed in Table 8-13. B is the sum of all
  unquantified benefits and disbenefits.
D Monetized benefits are presented using two different discount rates.
  Results calculated using 3 percent discount rate are recommended by
  EPA's Guidelines for Preparing Economic Analyses (U.S. EPA, 2000a).
  Results calculated using 7 percent discount rate are recommended by
  OMB Circular A-94 (OMB, 1992).


V. Public Participation and Requests for Comment


    The ICCR Federal Advisory Committee (i.e., the Coordinating 
Committee), which is discussed previously in this preamble, was 
designed and created to foster active participation from stakeholders, 
including environmental groups, regulated industries, local 
governments, Federal agencies, and State and local regulatory agencies. 
The stakeholders were able to participate in the development of FACA 
committee recommendations on many regulatory issues.
    The ICCR Coordinating Committee also encouraged the public to 
provide


[[Page 1697]]


 input on its data and recommendations throughout the 2-year charter. 
To enhance the public's ability to participate, EPA maintained a 
bulletin board on the Technology Transfer Network to disseminate 
information on the ICCR Coordinating Committee and Work Group meeting 
schedules and minutes, works in progress, and final recommendations. 
The public could submit comments on any information posted on the 
bulletin board to members of the ICCR Coordinating Committee or Work 
Group. Individuals could also attend the ICCR Coordinating Committee 
and Work Group meetings and comment on the information being presented 
and discussed. After the FACA charter expired, individual stakeholders 
and members of the public were encourage to submit individual comments 
and information to EPA staff. On several occasions after the FACA 
charter expired, EPA met with individual stakeholder groups to discuss 
the status of the proposed rulemaking and to hear their concerns and 
comments regarding the proposed rulemaking.
    To continue participation of stakeholders in the rulemaking 
process, EPA is requesting comments and data to support the proposed 
rule. The EPA requests comments on all aspects of the proposed rule 
from all interested parties.


VI. Administrative Requirements


A. Executive Order 12866, Regulatory Planning and Review


    Under Executive Order 12866 (58 FR 51735, October 4, 1993), the 
Agency must determine whether a regulatory action is ``significant'' 
and, therefore, subject to review by the Office of Management and 
Budget (OMB) and the requirements of the Executive Order. The Executive 
Order defines ``significant regulatory action'' as one that is likely 
to result in a rule that may:
    (1) Have an annual effect on the economy of $100 million or more or 
adversely affect in a material way the economy, a sector of the 
economy, productivity, competition, jobs, the environment, public 
health or safety, or State, local, or tribal governments or 
communities;
    (2) Create a serious inconsistency or otherwise interfere with an 
action taken or planned by another agency;
    (3) Materially alter the budgetary impact of entitlements, grants, 
user fees, or loan programs, or the rights and obligation of recipients 
thereof; or
    (4) Raise novel legal or policy issues arising out of legal 
mandates, the President's priorities, or the principles set forth in 
the Executive Order.
    Pursuant to the terms of Executive Order 12866, the Agency has 
determined that the proposed rule is a ``significant regulatory 
action'' because it has an annual effect on the economy of over $100 
million. As such, this proposed action was submitted to OMB for review.


B. Executive Order 13132, Federalism


    Executive Order 13132 (64 FR 43255, August 10, 1999), requires EPA 
to develop an accountable process to ensure ``meaningful and timely 
input by State and local officials in the development of regulatory 
policies that have federalism implications.'' ``Policies that have 
federalism implications'' is defined in the Executive Order to include 
regulations that have ``substantial direct effects on the States, on 
the relationship between the national government and the States, or on 
the distribution of power and responsibilities among the various levels 
of government.
    The proposed rule does not have federalism implications. It will 
not have substantial direct effects on the States, on the relationship 
between the national government and the States, or on the distribution 
of power and responsibilities among the various levels of government, 
as specified in Executive Order 13132.
    The agency is required by section 112 of the CAA, to establish the 
standards in the proposed rule. The proposed rule primarily affects 
private industry, and does not impose significant economic costs on 
State or local governments. The proposed rule does not include an 
express provision preempting State or local regulations. Thus, the 
requirements of section 6 of the Executive Order do not apply to the 
proposed rule.
    Although section 6 of Executive Order 13132 does not apply to the 
proposed rule, we consulted with representatives of State and local 
governments to enable them to provide meaningful and timely input into 
the development of the proposed rule. This consultation took place 
during the ICCR FACA committee meetings where members representing 
State and local governments participated in developing recommendations 
for EPA's combustion-related rulemakings, including the proposed rule. 
The concerns raised by representatives of State and local governments 
were considered during the development of the proposed rule.
    In the spirit of Executive Order 13132, and consistent with EPA 
policy to promote communications between EPA and State and local 
governments, EPA specifically solicits comment on the proposed rule 
from State and local officials.


C. Executive Order 13175, Consultation and Coordination With Indian 
Tribal Governments


    Executive Order 13175 (65 FR 67249, November 9, 2000), requires EPA 
to develop an accountable process to ensure ``meaningful and timely 
input by tribal officials in the development of regulatory policies 
that have tribal implications.'' The proposed rule does not have tribal 
implications, as specified in Executive Order 13175.
    The proposed rule does not significantly or uniquely affect the 
communities of Indian tribal governments. We do not know of any 
industrial-commercial-institutional boilers or process heaters owned or 
operated by Indian tribal governments. However, if there are any, the 
effect of the proposed rule on communities of tribal governments would 
not be unique or disproportionate to the effect on other communities. 
Thus, Executive Order 13175 does not apply to the proposed rule. The 
EPA specifically solicits additional comment on the proposed rule from 
tribal officials.


D. Executive Order 13045, Protection of Children From Environmental 
Health Risks and Safety Risks


    Executive Order 13045 (62 FR 19885, April 23, 1997) applies to any 
rule that: (1) Is determined to be ``economically significant'' as 
defined under Executive Order 12866, and (2) concerns an environmental 
health or safety risk that we have reason to believe may have a 
disproportionate effect on children. If the regulatory action meets 
both criteria, the Agency must evaluate the environmental health or 
safety effects of the proposed rule on children, and explain why the 
proposed rule is preferable to other potentially effective and 
reasonably feasible alternatives.
    The EPA interprets Executive Order 13045 as applying only to those 
regulatory actions that are based on health or safety risks, such that 
the analysis required under section 5-501 of the Executive Order has 
the potential to influence the regulation. The proposed rule is not 
subject to Executive Order 13045 because it is based on technology 
performance and not on health or safety risks.


E. Unfunded Mandates Reform Act of 1995


    Title II of the Unfunded Mandates Reform Act of 1995 (UMRA), Pub. 
L.


[[Page 1698]]


104-4, establishes requirements for Federal agencies to assess the 
effects of their regulatory actions on State, local, and tribal 
governments and the private sector. Under section 202 of the UMRA, we 
generally must prepare a written statement, including a cost-benefit 
analysis, for proposed and final rules with ``Federal mandates'' that 
may result in expenditures to State, local, and tribal governments, in 
the aggregate, or to the private sector, of $100 million or more in any 
1 year. Before promulgating a rule for which a written statement is 
needed, section 205 of the UMRA generally requires us to identify and 
consider a reasonable number of regulatory alternatives and adopt the 
least costly, most cost-effective or least burdensome alternative that 
achieves the objectives of the rule. The provisions of section 205 do 
not apply when they are inconsistent with applicable law. Moreover, 
section 205 allows us to adopt an alternative other than the least 
costly, most cost-effective or least burdensome alternative if the 
Administrator publishes with the final rule an explanation why that 
alternative was not adopted. Before we establish any regulatory 
requirements that may significantly or uniquely affect small 
governments, including tribal governments, we must develop a small 
government agency plan under section 203 of the UMRA. The plan must 
provide for notifying potentially affected small governments, enabling 
officials of affected small governments to have meaningful and timely 
input in the development of regulatory proposals with significant 
Federal intergovernmental mandates, and informing, educating, and 
advising small governments on compliance with the regulatory 
requirements.
    We have determined that the proposed rule contains a Federal 
mandate that may result in expenditures of $100 million or more for 
State, local, and Tribal governments, in the aggregate, or the private 
sector in any 1 year. Accordingly, we have prepared a written statement 
entitled ``Unfunded Mandates Reform Act Analysis for the Proposed 
Industrial Boilers and Process Heaters NESHAP'' under section 202 of 
the UMRA which is summarized below.
1. Statutory Authority
    As discussed in section I of this preamble, the statutory authority 
for the proposed rulemaking is section 112 of the CAA. Title III of the 
CAA Amendments was enacted to reduce nationwide air toxic emissions. 
Section 112(b) of the CAA lists the 188 chemicals, compounds, or groups 
of chemicals deemed by Congress to be HAP. These toxic air pollutants 
are to be regulated by NESHAP.
    Section 112(d) of the CAA directs us to develop NESHAP which 
require existing and new major sources to control emissions of HAP 
using MACT based standards. This NESHAP applies to all industrial, 
commercial, and institutional boilers and process heaters located at 
major sources of HAP emissions.
    In compliance with section 205(a) of the UMRA, we identified and 
considered a reasonable number of regulatory alternatives. Additional 
information on the costs and environmental impacts of these regulatory 
alternatives is presented in the docket.
    The regulatory alternative upon which the proposed rule is based 
represents the MACT floor for industrial boilers and process heaters 
and, as a result, it is the least costly and least burdensome 
alternative.
2. Social Costs and Benefits
    The regulatory impact analysis prepared for the proposed rule 
including the Agency's assessment of costs and benefits, is detailed in 
the ``Regulatory Impact Analysis for the Proposed Industrial Boilers 
and Process Heaters MACT'' in the docket. Based on estimated compliance 
costs associated with the proposed rule and the predicted change in 
prices and production in the affected industries, the estimated social 
costs of the proposed rule are $780 million (1999 dollars).
    It is estimated that 5 years after implementation of the proposed 
rule, HAP will be reduced by 58,500 tons per year due to reductions in 
arsenic, beryllium, dioxin, hydrochloric acid, and several other HAP 
from industrial boilers and process heaters. Studies have determined a 
relationship between exposure to these HAP and the onset of cancer, 
however, there are some questions remaining on how cancers that may 
result from exposure to these HAP can be quantified in terms of 
dollars. Therefore, the Agency is unable to provide a monetized 
estimate of the benefits of the HAP reduced by the proposed rule at 
this time. However, there are significant reductions in PM and in 
SO2 that occur. Reductions of 560,000 tons of PM with a 
diameter of less than or equal to 10 micrometers (PM10), 
159,000 tons of PM with a diameter of less than or equal to 2.5 
micrometers (PM10), and 112,000 tons of SO2 are 
expected to occur. These reductions occur from existing sources in 
operation 5 years after the implementation of the regulation and are 
expected to continue throughout the life of the affected sources. The 
major health effect that results from these PM and SO2 
emissions reductions is a reduction in premature mortality. Other 
health effects that occur are reductions in chronic bronchitis, asthma 
attacks, and work-lost days (i.e., days when employees are unable to 
work).
    While we are unable to monetize the benefits associated with the 
HAP emissions reductions, we are able to monetize the benefits 
associated with the PM and SO2 emissions reductions. For 
SO2 and PM, we estimated the benefits associated with health 
effects of PM but were unable to quantify all categories of benefits 
(particularly those associated with ecosystem and environmental 
effects). Unquantified benefits are noted with ``B'' in the estimates 
presented below. Our base estimate of the monetized benefits in 2005 
associated with the implementation of the proposed alternative is $16.1 
billion (1999 dollars) when using a 3 percent discount rate (or 
approximately $15.4 billion + B when using a 7 percent discount rate). 
This estimate, at a 3 percent discount rate, is about $15 billion (1999 
dollars) higher than the estimated social costs shown earlier in this 
section. The alternative estimate of benefits is $2.4 billion (1999 
dollars) when using a 3 percent discount rate (or approximately $2.6 
billion + B when using a 7 percent discount rate). This estimate, at a 
3 percent discount rate, is about $1.5 billion higher than the 
estimated social costs. The general approach to value benefits is 
discussed in more detail earlier in this preamble. For more detailed 
information on the benefits estimated for the proposed rulemaking, 
refer to the RIA in the docket.
3. Future and Disproportionate Costs
    The Unfunded Mandates Act requires that we estimate, where accurate 
estimation is reasonably feasible, future compliance costs imposed by 
the proposed rule and any disproportionate budgetary effects. Our 
estimates of the future compliance costs of the proposed rule are 
discussed previously in this preamble.
    We do not believe that there will be any disproportionate budgetary 
effects of the proposed rule on any particular areas of the country, 
State or local governments, types of communities (e.g., urban, rural), 
or particular industry segments. This is true for the 257 facilities 
owned by 54 different government bodies and is borne out by the results 
of the ``Economic Impact Analysis of the Proposed Industrial Boilers 
and Process Heaters NESHAP,''


[[Page 1699]]


the results of which are discussed previously in this preamble.
4. Effects on the National Economy
    The Unfunded Mandates Act requires that we estimate the effect of 
the proposed rule on the national economy. To the extent feasible, we 
must estimate the effect on productivity, economic growth, full 
employment, creation of productive jobs, and international 
competitiveness of the U.S. goods and services, if we determine that 
accurate estimates are reasonably feasible and that such effect is 
relevant and material.
    The nationwide economic impact of the proposed rule is presented in 
the ``Economic Impact Analysis for the Industrial Boilers and Process 
Heaters MACT'' in the docket. This analysis provides estimates of the 
effect of the proposed rule on some of the categories mentioned above. 
The results of the economic impact analysis are summarized previously 
in this preamble. The results show that there will be little impact on 
prices and output from the affected industries, and little impact on 
communities that may be affected by the proposed rule. In addition, 
there should be little impact on energy markets (in this case, coal, 
natural gas, petroleum products, and electricity). Hence, the potential 
impacts on the categories mentioned above should be minimal.
5. Consultation with Government Officials
    The Unfunded Mandates Act requires that we describe the extent of 
the Agency's prior consultation with affected State, local, and tribal 
officials, summarize the officials' comments or concerns, and summarize 
our response to those comments or concerns. In addition, section 203 of 
the UMRA requires that we develop a plan for informing and advising 
small governments that may be significantly or uniquely impacted by a 
proposal. Although the proposed rule does not affect any State, local, 
or Tribal governments, we have consulted with State and local air 
pollution control officials. We also have held meetings on the proposed 
rule with many of the stakeholders from numerous individual companies, 
environmental groups, consultants and vendors, labor unions, and other 
interested parties. We have added materials to the Air Docket to 
document these meetings.
    In addition, we have determined that the proposed rule contains no 
regulatory requirements that might significantly or uniquely affect 
small governments. While some small governments may have some sources 
affected by the proposed rule, the impacts are not expected to be 
significant. Therefore, today's proposed rule is not subject to the 
requirements of section 203 of the UMRA.


F. Regulatory Flexibility Act (RFA), as Amended by the Small Business 
Regulatory Enforcement Fairness Act of 1996 (SBREFA), 5 U.S.C. 601 et 
seq.


    The RFA generally requires an agency to prepare a regulatory 
flexibility analysis of any rule subject to notice and comment 
rulemaking requirements under the Administrative Procedure Act or any 
other statute unless the agency certifies that the rule will not have a 
significant economic impact on a substantial number of small entities. 
Small entities include small businesses, small organizations, and small 
governmental jurisdictions.
    For purposes of assessing the impacts of today's proposed rule on 
small entities, small entity is defined as: (1) A small business 
according to Small Business Administration (SBA) size standards by the 
North American Industry Classification System category of the owning 
entity. The range of small business size standards for the 40 affected 
industries ranges from 500 to 1,000 employees, except for petroleum 
refining and electric utilities. In these latter two industries, the 
size standard is 1,500 employees and a mass throughput of 75,000 
barrels/day or less, and 4 million kilowatt-hours of production or 
less, respectively; (2) a small governmental jurisdiction that is a 
government of a city, county, town, school district or special district 
with a population of less than 50,000; and (3) a small organization 
that is any not-for-profit enterprise which is independently owned and 
operated and is not dominant in its field.
    After considering the economic impact of the proposed rule on small 
entities, EPA certifies that this action will not have a significant 
impact on a substantial number of small entities. Based on SBA size 
definitions for the affected industries and reported sales and 
employment data, the Agency identified 185 of the 576 companies, or 32 
percent, owning affected facilities as small businesses. Although small 
businesses represent 32 percent of the companies within the source 
category, they are expected to incur 4 percent of the total compliance 
costs of $862.7 million (1998 dollars). There are only ten small firms 
with compliance costs equal to or greater than 3 percent of their 
sales. In addition, there are 24 small firms with cost-to-sales ratios 
between 1 and 3 percent.
    An economic impact analysis was performed to estimate the changes 
in product price and production quantities for the proposed rule. As 
mentioned in the summary of economic impacts, the estimated changes in 
prices and output for affected firms is no more than 0.05 percent.
    This analysis indicates that the proposed rule should not generate 
a significant impact on a substantial number of small entities for 
following reasons. First, there are 34 small firms (or 18 percent of 
all affected small firms) with compliance costs equal to or greater 
than 1 percent of their sales. Of these, ten small firms (or 5 percent 
of all affected small firms) with compliance costs equal to or greater 
than 3 percent of their sales. Second, the results of the economic 
impact analysis show minimal impacts on prices and output from affected 
firms, including small entities, due to the implementation of the 
proposed rule. For more information, consult the docket for the 
proposed rule.
    The proposed rule will not have a significant economic impact on a 
substantial number of small entities as a result of several decisions 
EPA made regarding the development of the rule which resulted in 
limiting the impact of the rule on small entities. First, as mentioned 
earlier in this preamble, EPA identified small units (heat input of 10 
MMBtu/hr or less) and limited use boilers (operate less than 10 percent 
of the time) as separate subcategories different from large units. Many 
small and limited use units are located at small entities. As also 
discussed earlier, the results of the MACT floor analysis for these 
subcategories of existing sources was that no MACT floor could be 
identified except for the limited use solid fuel subcategory which is 
less stringent than the MACT floor for large units. Furthermore, the 
results of the beyond-the-floor analysis for these subcategories 
indicated that the costs would be too high to consider them feasible 
options. Consequently, the proposed rule contains no emission 
limitations for any of the existing small and limited use subcategories 
except the existing limited use solid fuel subcategory. In addition, 
the proposed alternative metals emission limit resulted in minimizing 
the impacts on small entities since some of the potential entities 
burning a fuel containing very little metals are small entities. We 
continue to be interested in the potential impacts of the proposed rule 
on small entities and welcome comments on issues related to such 
impacts.


[[Page 1700]]


G. Paperwork Reduction Act


    The information collection requirements in the proposed rule will 
be submitted for approval to the Office of Management and Budget under 
the Paperwork Reduction Act, 44 U.S.C. 3501 et seq. An Information 
Collection Request (ICR) document has been prepared by EPA (ICR No. 
2028.01) and a copy may be obtained from Susan Auby by mail at the 
Collection Strategies Division, U.S. Environmental Protection Agency 
(2822), 1200 Pennsylvania Avenue NW., Washington, DC 20460, by e-mail 
at auby.susan@epa.gov, or by calling (202) 566-1672. A copy may also be 
downloaded off the Internet at http://www.epa.gov/icr.
    The information requirements are based on notification, 
recordkeeping, and reporting requirements in the NESHAP General 
Provisions (40 CFR part 63, subpart A), which are mandatory for all 
operators subject to national emission standards. These recordkeeping 
and reporting requirements are specifically authorized by section 114 
of the CAA (42 U.S.C. 7414). All information submitted to EPA pursuant 
to the recordkeeping and reporting requirements for which a claim of 
confidentiality is made is safeguarded according to Agency policies set 
forth in 40 CFR part 2, subpart B.
    The proposed rule would require maintenance inspections of the 
control devices but would not require any notifications or reports 
beyond those required by the General Provisions. The recordkeeping 
requirements require only the specific information needed to determine 
compliance.
    The annual monitoring, reporting, and recordkeeping burden for this 
collection (averaged over the first 3 years after the effective date of 
the standards) is estimated to be $165 million. This includes 2.7 
million labor hours per year at a total labor cost of $142 million per 
year, and total non-labor capital costs of $24 million per year. This 
estimate includes a one-time performance test, semiannual excess 
emission reports, maintenance inspections, notifications, and 
recordkeeping. Monitoring costs were also included in the cost 
estimates presented in the control costs impacts estimates in section 
IV.D of this preamble. The total burden for the Federal government 
(averaged over the first 3 years after the effective date of the 
standard) is estimated to be 346,000 hours per year at a total labor 
cost of $14 million per year.
    Burden means the total time, effort, or financial resources 
expended by persons to generate, maintain, retain, or disclose or 
provide information to or for a Federal agency. This includes the time 
needed to review instructions; develop, acquire, install, and utilize 
technology and systems for the purposes of collecting, validating, and 
verifying information, processing and maintaining information, and 
disclosing and providing information; adjust the existing ways to 
comply with any previously applicable instructions and requirements; 
train personnel to be able to respond to a collection of information; 
search data sources; complete and review the collection of information; 
and transmit or otherwise disclose the information.
    An Agency may not conduct or sponsor, and a person is not required 
to respond to, a collection of information unless it displays a 
currently valid OMB control number. The OMB control numbers for our 
regulations are listed in 40 CFR part 9 and 48 CFR chapter 15.
    Comments are requested on the Agency's need for this information, 
the accuracy of the provided burden estimates, and any suggested 
methods for minimizing respondent burden, including through the use of 
automated collection techniques. Send comments on the ICR to the 
Director, Collection Strategies Division, U.S. Environmental Protection 
Agency (2822), 1200 Pennsylvania Ave., NW., Washington, DC 20460; and 
to the Office of Information and Regulatory Affairs, Office of 
Management and Budget, 725 17th St., NW., Washington, DC 20503, marked 
``Attention: Desk Officer for EPA.'' Include the ICR number in any 
correspondence.
    Since OMB is required to make a decision concerning the ICR between 
30 and 60 days after January 13, 2003, a comment to OMB is best assured 
of having its full effect if OMB receives it by February 12, 2003. The 
final rule will respond to any OMB or public comments on the 
information collection requirements contained in the proposed rule.


H. National Technology Transfer and Advancement Act


    Section 12(d) of the National Technology Transfer and Advancement 
Act (NTTAA) of 1995 (Public Law 104-113; 15 U.S.C. 272 note) directs 
the EPA to use voluntary consensus standards in their regulatory and 
procurement activities unless to do so would be inconsistent with 
applicable law or otherwise impractical. Voluntary consensus standards 
are technical standards (e.g., materials specifications, test methods, 
sampling procedures, business practices) developed or adopted by one or 
more voluntary consensus bodies. The NTTAA directs EPA to provide 
Congress, through annual reports to the Office of Management and 
Budget, with explanations when an agency does not use available and 
applicable voluntary consensus standards.
    This rulemaking involves technical standards. The EPA cites the 
following standards in the proposed rule: EPA Methods 1, 2, 2F, 2G, 3A, 
3B, 4, 5, 5D, 17, 19, 26, 26A, 29 of 40 CFR part 60. Consistent with 
the NTTAA, EPA conducted searches to identify voluntary consensus 
standards in addition to these EPA methods. No applicable voluntary 
consensus standards were identified for EPA Methods 2F, 2G, 5D, and 19. 
The search and review results have been documented and are placed in 
the docket for the proposed rule.
    The three voluntary consensus standards described below were 
identified as acceptable alternatives to EPA test methods for the 
purposes of the proposed rule.
    The voluntary consensus standard ASME PTC 19-10-1981--Part 10, 
``Flue and Exhaust Gas Analyses,'' is cited in the proposed rule for 
its manual method for measuring the oxygen, carbon dioxide, and carbon 
monoxide content of exhaust gas. This part of ASME PTC 19-10-1981--Part 
10 is an acceptable alternative to Method 3B.
    The voluntary consensus standard ASTM D6522-00, ``Standard Test 
Method for the Determination of Nitrogen Oxides, Carbon Monoxide, and 
Oxygen Concentrations in Emissions from Natural Gas-Fired Reciprocating 
Engines, Combustion Turbines, Boilers and Process Heaters Using 
Portable Analyzers'' is an acceptable alternative to EPA Method 3A for 
identifying carbon monoxide and oxygen concentrations for the proposed 
rule when the fuel is natural gas.
    The voluntary consensus standard ASTM Z65907, ``Standard Method for 
Both Speciated and Elemental Mercury Determination,'' is an acceptable 
alternative to EPA Method 29 (portion for mercury only) for the purpose 
of the proposed rule. This standard can be used in the proposed rule to 
determine the mercury concentration in stack gases for boilers with 
rated heat input capacities of greater than 250 MMBtu per hour.
    In addition to the voluntary consensus standards EPA uses in the 
proposed rule, the search for emissions measurement procedures 
identified 15 other voluntary consensus standards.


[[Page 1701]]


The EPA determined that 13 of these 15 standards identified for 
measuring emissions of the HAP or surrogates subject to emission 
standards in the proposed rule were impractical alternatives to EPA 
test methods for the purposes of the rule. Therefore, EPA does not 
intend to adopt these standards for this purpose. The reasons for this 
determination for the 13 methods are discussed below.
    The voluntary consensus standard ASTM D3154-00, ``Standard Method 
for Average Velocity in a Duct (Pitot Tube Method),'' is impractical as 
an alternative to EPA Methods 1, 2, 3B, and 4 for the purposes of the 
proposed rulemaking since the standard appears to lack in quality 
control and quality assurance requirements. Specifically, ASTM D3154-00 
does not include the following: (1) Proof that openings of standard 
pitot tube have not plugged during the test; (2) if differential 
pressure gauges other than inclined manometers (e.g., magnehelic 
gauges) are used, their calibration must be checked after each test 
series; and (3) the frequency and validity range for calibration of the 
temperature sensors.
    The voluntary consensus standard ASTM D3464-96 (2001), ``Standard 
Test Method Average Velocity in a Duct Using a Thermal Anemometer,'' is 
impractical as an alternative to EPA Method 2 for the purposes of the 
proposed rule primarily because applicability specifications are not 
clearly defined, e.g., range of gas composition, temperature limits. 
Also, the lack of supporting quality assurance data for the calibration 
procedures and specifications, and certain variability issues that are 
not adequately addressed by the standard limit EPA's ability to make a 
definitive comparison of the method in these areas.
    The voluntary consensus standard ISO 10780:1994, ``Stationary 
Source Emissions-Measurement of Velocity and Volume Flow-Rate of Gas 
Streams in Ducts,'' is impractical as an alternative to EPA Method 2 in 
the proposed rule. The standard recommends the use of an L-shaped 
pitot, which historically has not been recommended by EPA. The EPA 
specifies the S-type design which has large openings that are less 
likely to plug up with dust.
    The voluntary consensus standard, CAN/CSA Z223.2-M86 (1999), 
``Method for the Continuous Measurement of Oxygen, Carbon Dioxide, 
Carbon Monoxide, Sulphur Dioxide, and Oxides of Nitrogen in Enclosed 
Combustion Flue Gas Streams,'' is unacceptable as a substitute for EPA 
Method 3A since it does not include quantitative specifications for 
measurement system performance, most notably the calibration procedures 
and instrument performance characteristics. The instrument performance 
characteristics that are provided are nonmandatory and also do not 
provide the same level of quality assurance as the EPA methods. For 
example, the zero and span/calibration drift is only checked weekly, 
whereas the EPA methods requires drift checks after each run.
    Two very similar voluntary consensus standards, ASTM D5835-95 
(2001), ``Standard Practice for Sampling Stationary Source Emissions 
for Automated Determination of Gas Concentration,'' and ISO 10396:1993, 
``Stationary Source Emissions: Sampling for the Automated Determination 
of Gas Concentrations,'' are impractical alternatives to EPA Method 3A 
for the purposes of the proposed rule because they lack in detail and 
quality assurance/quality control requirements. Specifically, these two 
standards do not include the following: (1) Sensitivity of the method; 
(2) acceptable levels of analyzer calibration error; (3) acceptable 
levels of sampling system bias; (4) zero drift and calibration drift 
limits, time span, and required testing frequency; (5) a method to test 
the interference response of the analyzer; (6) procedures to determine 
the minimum sampling time per run and minimum measurement time; and (7) 
specifications for data recorders, in terms of resolution (all types) 
and recording intervals (digital and analog recorders, only).
    The voluntary consensus standard ISO 12039:2001, ``Stationary 
Source Emissions--Determination of Carbon Monoxide, Carbon Dioxide, and 
Oxygen--Automated Methods,'' is not acceptable as an alternative to EPA 
Method 3A. This ISO standard is similar to EPA Method 3A, but is 
missing some key features. In terms of sampling, the hardware required 
by ISO 12039:2001 does not include a 3-way calibration valve assembly 
or equivalent to block the sample gas flow while calibration gases are 
introduced. In its calibration procedures, ISO 12039:2001 only 
specifies a two-point calibration while EPA Method 3A specifies a 
three-point calibration. Also, ISO 12039:2001 does not specify 
performance criteria for calibration error, calibration drift, or 
sampling system bias tests as in the EPA method, although checks of 
these quality control features are required by the ISO standard.
    The voluntary consensus standard ASME PTC-38-80 R85 (1985), 
``Determination of the Concentration of Particulate Matter in Gas 
Streams,'' is not acceptable as an alternative for EPA Method 5 because 
ASTM PTC-38-80 is not specific about equipment requirements, and 
instead presents the options available and the pro's and con's of each 
option. The key specific differences between ASME PTC-38-80 and the EPA 
methods are that the ASME standard: (1) Allows in-stack filter 
placement as compared to the out-of-stack filter placement in EPA 
Methods 5 and 17; (2) allows many different types of nozzles, pitots, 
and filtering equipment; (3) does not specify a filter weighing 
protocol or a minimum allowable filter weight fluctuation as in the EPA 
methods; and (4) allows filter paper to be only 99 percent efficient, 
as compared to the 99.95 percent efficiency required by the EPA 
methods.
    The voluntary consensus standard ASTM D3685/D3685M-98, ``Test 
Methods for Sampling and Determination of Particulate Matter in Stack 
Gases,'' is similar to EPA Methods 5 and 17, but is lacking in the 
following areas that are needed to produce quality, representative 
particulate data:
    (1) Requirement that the filter holder temperature should be 
between 120[deg]C and 134[deg]C, and not just ``above the acid dew-
point;'' (2) detailed specifications for measuring and monitoring the 
filter holder temperature during sampling; (3) procedures similar to 
EPA Methods 1, 2, 3, and 4, that are required by EPA Method 5; (4) 
technical guidance for performing the Method 5 sampling procedures, 
e.g., maintaining and monitoring sampling train operating temperatures, 
specific leak check guidelines and procedures, and use of reagent 
blanks for determining and subtracting background contamination; and 
(5) detailed equipment and/or operational requirements, e.g., component 
exchange leak checks, use of glass cyclones for heavy particulate 
loading and/or water droplets, operating under a negative stack 
pressure, exchanging particulate loaded filters, sampling preparation 
and implementation guidance, sample recovery guidance, data reduction 
guidance, and particulate sample calculations input.
    The voluntary consensus standard ISO 9096:1992, ``Determination of 
Concentration and Mass Flow-Rate of Particulate Matter in Gas Carrying 
Ducts--Manual Gravimetric Method,'' is not acceptable as an alternative 
for EPA Method 5. Although sections of ISO 9096 incorporate EPA Methods 
1, 2, and 5 to some degree, this ISO standard is not equivalent to EPA 
Method 5 for collection of particulate matter. The standard ISO 9096 
does not provide applicable technical guidance for performing many of 
the integral


[[Page 1702]]


procedures specified in Methods 1, 2, and 5. Major performance and 
operational details are lacking or nonexistent, and detailed quality 
assurance/quality control guidance for the sampling operations required 
to produce quality, representative particulate data (e.g., guidance for 
maintaining and monitoring train operating temperatures, specific leak 
check guidelines and procedures, and sample preparation and recovery 
procedures) are not provided by the standard, as in EPA Method 5. Also, 
details of equipment and/or operational requirements, such as those 
specified in EPA Method 5, are not included in the ISO standard, e.g., 
stack gas moisture measurements, data reduction guidance, and 
particulate sample calculations.
    The voluntary consensus standard CAN/CSA Z223.1-M1977, ``Method for 
the Determination of Particulate Mass Flows in Enclosed Gas Streams,'' 
is not acceptable as an alternative for EPA Method 5. Detailed 
technical procedures and quality control measures that are required in 
EPA Methods 1, 2, 3, and 4 are not included in CAN/CSA Z223.1. Second, 
CAN/CSA Z223.1 does not include the EPA Method 5 filter weighing 
requirement to repeat weighing every 6 hours until a constant weight is 
achieved. Third, EPA Method 5 requires the filter weight to be reported 
to the nearest 0.1 mg, while CAN/CSA Z223.1 requires only to the 
nearest 0.5 mg. Also, CAN/CSA Z223.1 allows the use of a standard pitot 
for velocity measurement when plugging of the tube opening is not 
expected to be a problem. Whereas, EPA Method 5 requires an S-shaped 
pitot.
    The voluntary consensus standard EN 1911-1,2,3 (1998), ``Stationary 
Source Emissions--Manual Method of Determination of HCl--Part 1: 
Sampling of Gases Ratified European Text--Part 2: Gaseous Compounds 
Absorption Ratified European Text--Part 3: Adsorption Solutions 
Analysis and Calculation Ratified European Text,'' is impractical as an 
alternative to EPA Methods 26 and 26A. Part 3 of this standard cannot 
be considered equivalent to EPA Method 26 or 26A because the sample 
absorbing solution (water) would be expected to capture both HCl and 
chlorine gas, if present, without the ability to distinguish between 
the two. The EPA Methods 26 and 26A use an acidified absorbing solution 
to first separate HCl and chlorine gas so that they can be selectively 
absorbed, analyzed, and reported separately. In addition, in EN 1911 
the absorption efficiency for chlorine gas would be expected to vary as 
the pH of the water changed during sampling.
    The voluntary consensus standard EN 13211 (1998), is not acceptable 
as an alternative to the mercury portion of EPA Method 29 primarily 
because it is not validated for use with impingers, as in the EPA 
method, although the method describes procedures for the use of 
impingers. This European standard is validated for the use of fritted 
bubblers only and requires the use of a side (split) stream arrangement 
for isokinetic sampling because of the low sampling rate of the 
bubblers (up to 3 liters per minute, maximum). Also, only two bubblers 
(or impingers) are required by EN 13211, whereas EPA Method 29 require 
the use of six impingers. In addition, EN 13211 does not include many 
of the quality control procedures of EPA Method 29, especially for the 
use and calibration of temperature sensors and controllers, sampling 
train assembly and disassembly, and filter weighing.
    Two of the 15 voluntary consensus standards identified in this 
search were not available at the time the review was conducted for the 
purposes of the proposed rule because they are under development by a 
voluntary consensus body: ASME/BSR MFC 13M, ``Flow Measurement by 
Velocity Traverse,'' for EPA Method 2 (and possibly 1); and ASME/BSR 
MFC 12M, ``Flow in Closed Conduits Using Multiport Averaging Pitot 
Primary Flowmeters,'' for EPA Method 2.
    Section 63.7520 and Tables 4A through 4D to subpart DDDDD, 40 CFR 
part 63, list the EPA testing methods included in the proposed rule. 
Under Sec.  63.7(f) and Sec.  63.8(f) of subpart A of the General 
Provisions, a source may apply to EPA for permission to use alternative 
test methods or alternative monitoring requirements in place of any of 
the EPA testing methods, performance specifications, or procedures.


I. Executive Order 13211, Actions Concerning Regulations That 
Significantly Affect Energy Supply, Distribution, or Use


    Executive Order 13211, (66 FR 28355, May 22, 2001), provides that 
agencies shall prepare and submit to the Administrator of the Office of 
Information and Regulatory Affairs, Office of Management and Budget, a 
Statement of Energy Effects for certain actions identified as 
significant energy actions. Section 4(b) of Executive Order 13211 
defines ``significant energy actions'' as ``any action by an agency 
(normally published in the Federal Register) that promulgates or is 
expected to lead to the promulgation of a final rule or regulation, 
including notices of inquiry, advance notices of proposed rulemaking, 
and notices of proposed rulemaking: (1)(i) that is a significant 
regulatory action under Executive Order 12866 or any successor order, 
and (ii) is likely to have a significant adverse effect on the supply, 
distribution, or use of energy; or (2) that is designated by the 
Administrator of the Office of Information and Regulatory Affairs as a 
significant energy action.'' The proposed rule is not a ``significant 
regulatory action'' because it is not likely to have a significant 
adverse effect on the supply, distribution, or use of energy. The basis 
for the determination is as follows.
    The reduction in petroleum product output, which includes 
reductions in fuel production, is estimated at only 0.001 percent, or 
about 68 barrels per day based on 2000 U.S. fuel production nationwide. 
That is a minimal reduction in nationwide petroleum product output. The 
reduction in coal production is estimated at only 0.014 percent, or 
about 3.5 million tons per year (or less than 1,000 tons per day) based 
on 2000 U.S. coal production nationwide. The combination of the 
increase in electricity usage estimated in section IV. C of this 
preamble with the effect of the increased price of affected output 
yields an increase in electricity output estimated at only 0.012 
percent, or about 0.72 billion kilowatt-hours per year based on 2000 
U.S. electricity production nationwide. All energy price changes 
estimated show no increase in price more than 0.05 percent nationwide, 
and a similar result occurs for energy distribution costs. We also 
expect that there will be no discernable impact on the import of 
foreign energy supplies, and no other adverse outcomes are expected to 
occur with regards to energy supplies. All of the results presented 
above account for the pass through of costs to consumers, as well as 
the cost impact to producers. For more information on the estimated 
energy effects, please refer to the economic impact analysis for the 
proposed rule. The analysis is available in the public docket.
    Therefore, we conclude that the proposed rule when implemented is 
not likely to have a significant adverse effect on the supply, 
distribution, or use of energy.


List of Subjects in 40 CFR Part 63


    Environmental protection, Administrative practice and procedure, 
Air pollution control, Hazardous substances, Intergovernmental 
relations, Reporting and recordkeeping requirements.




[[Page 1703]]




    Dated: November 26, 2002.
Christine Todd Whitman,
Administrator.


    For the reasons stated in the preamble, title 40, chapter I, part 
63 of the Code of the Federal Regulations is proposed to be amended as 
follows:


PART 63--[AMENDED]


    1. The authority citation for part 63 continues to read as follows:


    Authority: 42 U.S.C. 7401, et seq.


    2. Part 63 is amended by adding subpart DDDDD to read as follows:
Subpart DDDDD--National Emission Standards for Hazardous Air Pollutants 
for Industrial, Commercial, and Institutional Boilers and Process 
Heaters


What This Subpart Covers


Sec.
63.7480 What is the purpose of this subpart?
63.7485 Am I subject to this subpart?
63.7490 What parts of my facility does this subpart cover?
63.7495 When do I have to comply with this subpart?


Emission Limitations and Work Practice Standards


63.7500 What emission limitations and work practice standards must I 
meet?


General Compliance Requirements


63.7505 What are my general requirements for complying with this 
subpart?


Testing and Initial Compliance Requirements


63.7510 By what date must I conduct performance tests or other 
initial compliance demonstrations?
63.7515 When must I conduct subsequent performance tests?
63.7520 What performance tests, design evaluations, and other 
procedures must I use?
63.7525 What are my monitoring, installation, operation, and 
maintenance requirements?
63.7530 How do I demonstrate initial compliance with the emission 
limitations and work practice standards?


Continuous Compliance Requirements


63.7535 How do I monitor and collect data to demonstrate continuous 
compliance?
63.7540 How do I demonstrate continuous compliance with the emission 
limitations and work practice standards?


Notifications, Reports, and Records


63.7545 What notifications must I submit and when?
63.7550 What reports must I submit and when?
63.7555 What records must I keep?
63.7560 In what form and how long must I keep my records?


Other Requirements and Information


63.7565 What parts of the General Provisions apply to me?
63.7570 Who implements and enforces this subpart?
63.7575 What definitions apply to this subpart?


Tables to Subpart DDDDD of Part 63


Table 1 to Subpart DDDDD of Part 63--Emission Limits
Table 2.A to Subpart DDDDD of Part 63--Operating Limits for Boilers 
and Process Heaters in the Large, Limited Use, or Small Solid Fuel 
Subcategories
Table 2.B to Subpart DDDDD of Part 63--Operating Limits for Boilers 
and Process Heaters in the Large, Limited Use, or Small Liquid Fuel 
Subcategories
Table 3 to Subpart DDDDD of Part 63--Work Practice Standards
Table 4.A to Subpart DDDDD of Part 63--Requirements for Performance 
Tests for Particulate Matter Emissions or Total Selected Metals 
Emissions from Boilers or Process Heaters in Large, Limited Use, or 
Small Solid Fuel Subcategories
Table 4.B to Subpart DDDDD of Part 63--Requirements for Performance 
Tests for Particulate Matter Emissions from Boilers or Process 
Heaters in Large, Limited Use, or Small Liquid Fuel Subcategories
Table 4.C to Subpart DDDDD of Part 63--Requirements for Performance 
Tests for Hydrogen Chloride Emissions from Boilers or Process 
Heaters in Large, Limited Use, or Small Solid Fuel Subcategories
Table 4.D to Subpart DDDDD of Part 63--Requirements for Performance 
Tests for Hydrogen Chloride Emissions from Boilers or Process 
Heaters in Large, Limited Use, or Small Liquid Fuel Subcategories
Table 4.E to Subpart DDDDD of Part 63--Requirements for Performance 
Tests for Mercury Emissions from Boilers or Process Heaters in 
Large, Limited Use, or Small Solid Fuel Subcategories
Table 5.A to Subpart DDDDD of Part 63--Initial Compliance With 
Emission Limitations for Particulate Matter or Total Selected Metals 
for Boilers or Process Heaters in Large, Limited Use, or Small Solid 
Fuel Subcategories
Table 5.B to Subpart DDDDD of Part 63--Initial Compliance With 
Emission Limitations for Particulate Matter for Boilers or Process 
Heaters in Large, Limited Use, or Small Liquid Fuel Subcategories
Table 5.C to Subpart DDDDD of Part 63--Initial Compliance With 
Emission Limitations for Hydrogen Chloride for Boilers or Process 
Heaters in Large, Limited Use, or Small Solid Fuel Subcategories
Table 5.D to Subpart DDDDD of Part 63--Initial Compliance With 
Emission Limitations for Hydrogen Chloride for Boilers or Process 
Heaters in Large, Limited Use, or Small Liquid Fuel Subcategories
Table 5.E to Subpart DDDDD of Part 63--Initial Compliance With 
Emission Limitations for Mercury for Boilers or Process Heaters in 
Large, Limited Use, or Small Solid Fuel, Subcategories
Table 6 to Subpart DDDDD of Part 63--Initial Compliance with Work 
Practice Standards
Table 7.A to Subpart DDDDD of Part 63--Continuous Compliance with 
Emission Limitations for Boilers or Process Heaters in Large, 
Limited Use, or Small Solid Fuel Subcategories
Table 7.B to Subpart DDDDD of Part 63--Continuous Compliance with 
Emission Limitations for Boilers or Process Heaters in Large, 
Limited Use, or Small Liquid Fuel Subcategories
Table 8 to Subpart DDDDD of Part 63--Continuous Compliance with Work 
Practice Standards
Table 9 to Subpart DDDDD of Part 63--Requirements for Reports
Table 10 to Subpart DDDDD of Part 63--Applicability of General 
Provisions to Subpart DDDDD


Subpart DDDDD--National Emission Standards for Hazardous Air 
Pollutants for Industrial, Commercial, and Institutional Boilers 
and Process Heaters


What This Subpart Covers




Sec.  63.7480  What is the purpose of this subpart?


    This subpart establishes national emission limitations and work 
practice standards for hazardous air pollutants emitted from 
industrial, commercial, and institutional boilers and process heaters. 
This subpart also establishes requirements to demonstrate initial and 
continuous compliance with the emission limitations and work practice 
standards.




Sec.  63.7485  Am I subject to this subpart?


    You are subject to this subpart if you own or operate an 
industrial, commercial, or institutional boiler or process heater that 
is located at, or is part of, a major source of hazardous air 
pollutants (HAP) emissions, except as specifically exempted in Sec.  
63.7490.
    (a) An industrial, commercial, or institutional boiler is an 
enclosed device using controlled flame combustion and having the 
primary purpose of recovering thermal energy in the form of steam or 
hot water. Waste heat boilers are excluded. A process heater is an 
enclosed device using controlled flame with the unit's primary purpose 
being to transfer heat indirectly to process streams (liquids, gases, 
or solids) instead of generating steam.
    (b) A major source of HAP emissions is any stationary source or 
group of stationary sources located within a contiguous area and under 
common control that emits or has the potential to emit any single HAP 
at a rate of 9.07 megagrams (10 tons) or more per year or any 
combination of HAP at a rate of


[[Page 1704]]


22.68 megagrams (25 tons) or more per year.




Sec.  63.7490  What parts of my facility does this subpart cover?


    (a) This subpart applies to each new, reconstructed, or existing 
affected source.
    (b) The affected source is each industrial, commercial, or 
institutional boiler or process heater, as defined in Sec.  63.7485 
that is not one of the types of combustion units listed in Sec.  
63.7490(b)(1) through (10).
    (1) A municipal waste combustor covered by 40 CFR part 60, subpart 
AAAA, subpart BBBB, subpart Eb or subpart Cb.
    (2) A hospital/medical/infectious waste incinerator covered by 40 
CFR part 60, subpart Ce or subpart Ec.
    (3) An electric utility steam generating unit that is a fossil 
fuel-fired combustion unit of more than 25 megawatts that serves a 
generator that produces electricity for sale. A unit that cogenerates 
steam and electricity and supplies more than one-third of its potential 
electric output capacity and more than 25 megawatts electrical output 
to any utility power distribution system for sale is considered an 
electric utility steam generating unit.
    (4) A boiler or process heater required to have a permit under 
section 3005 of the Solid Waste Disposal Act or covered by 40 CFR part 
63, subpart EEE (e.g., hazardous waste combustors).
    (5) A commercial and industrial solid waste incineration unit 
covered by 40 CFR part 60, subpart CCCC or subpart DDDD.
    (6) A recovery boiler or furnace covered by 40 CFR part 63, subpart 
MM.
    (7) A boiler or process heater that is used specifically for 
research and development. This does not include units that only provide 
steam to a process at a research and development facility.
    (8) A hot water heater as defined in this subpart.
    (9) A refining kettle covered by 40 CFR part 63, subpart X.
    (10) An ethylene cracking furnace covered by 40 CFR part 63, 
subpart YY.
    (c) An affected source is a new affected source if you commenced 
construction of the affected source after January 13, 2003 and you meet 
the applicability criteria at the time you commenced construction.
    (d) An affected source is reconstructed if you meet the criteria as 
defined in Sec.  63.2.
    (e) An affected source is existing if it is not new or 
reconstructed.




Sec.  63.7495  When do I have to comply with this subpart?


    (a) If you have a new or reconstructed affected source, you must 
comply with this subpart according to paragraph (a)(1) or (2) of this 
section.
    (1) If you start up your affected source before [DATE THE FINAL 
RULE IS PUBLISHED IN THE FEDERAL REGISTER], then you must comply with 
the emission limitations and work practice standards for new and 
reconstructed sources in this subpart no later than [DATE THE FINAL 
RULE IS PUBLISHED IN THE FEDERAL REGISTER].
    (2) If you startup your affected source after [DATE THE FINAL RULE 
IS PUBLISHED IN THE FEDERAL REGISTER], then you must comply with the 
emission limitations and work practice standards for new and 
reconstructed sources in this subpart upon startup of your affected 
source.
    (b) If you have an existing affected source, you must comply with 
the emission limitations for existing sources no later than 3 years 
after [DATE THE FINAL RULE IS PUBLISHED IN THE FEDERAL REGISTER].
    (c) If you have an area source that increases its emissions or its 
potential to emit such that it becomes a major source of HAP, 
paragraphs (c)(1) and (2) of this section apply to you.
    (1) Any new or reconstructed boiler or process heater at the 
existing facility must be in compliance with this subpart upon startup.
    (2) Any existing boiler or process heater at the existing facility 
must be in compliance with this subpart within 3 years after the 
facility becomes a major source.
    (d) You must meet the notification requirements in Sec.  63.7545 
according to the schedule in Sec.  63.7545 and in subpart A of this 
part. Some of the notifications must be submitted before you are 
required to comply with the emission limitations and work practice 
standards in this subpart.


Emission Limitations and Work Practice Standards




Sec.  63.7500  What emission limitations and work practice standards 
must I meet?


    (a) You must meet the requirements in paragraphs (a)(1) through (3) 
of this section.
    (1) You must meet each emission limit in Table 1 to this subpart 
that applies to you.
    (2) You must meet each operating limit in Tables 2.A and 2.B to 
this subpart that applies to you. If you use a control device or 
combination of control devices not covered in Tables 2.A or 2.B to this 
subpart, or you wish to establish and monitor an alternative operating 
limit and alternative monitoring parameters, you must apply to the 
Administrator for approval of alternative monitoring under Sec.  
63.8(f).
    (3) You must meet each work practice standard in Table 3 to this 
subpart that applies to you.
    (b) If your new or reconstructed boiler or process heater is in one 
of the liquid fuel subcategories (the large liquid fuel subcategory, 
the limited use liquid fuel subcategory, or the small liquid fuel 
subcategory) and burns only fossil fuels and other gases and does not 
burn any residual oil, you are subject to the emission limits in Table 
1 to this subpart, but you are not required to conduct a performance 
test to demonstrate compliance with the emission limits. However, you 
must meet all applicable requirements in Sec. Sec.  63.7530 and 
63.7535.
    (c) As provided in Sec.  63.6(g), the Environmental Protection 
Agency (EPA) may choose to grant you permission to use an alternative 
to the work practice standards in this section.


General Compliance Requirements




Sec.  63.7505  What are my general requirements for complying with this 
subpart?


    (a) You must be in compliance with the emission limitations 
(including operating limits) and the work practice standards in this 
subpart at all times, except during periods of startup, shutdown, and 
malfunction.
    (b) You must always operate and maintain your affected source, 
including air pollution control and monitoring equipment, according to 
the provisions in Sec.  63.6(e)(1)(i).
    (c) You must develop a site-specific monitoring plan according to 
the requirements in paragraphs (c)(1) through (4) of this section.
    (1) For each monitoring system required in this section, you must 
develop and submit for approval a site-specific monitoring plan that 
addresses paragraphs (c)(1)(i) through (iii) of this section.
    (i) Installation of the continuous monitoring system (CMS) sampling 
probe or other interface at a measurement location relative to each 
affected process unit such that the measurement is representative of 
control of the exhaust emissions (e.g., on or downstream of the last 
control device);
    (ii) Performance and equipment specifications for the sample 
interface, the pollutant concentration or parametric signal analyzer, 
and the data collection and reduction systems; and


[[Page 1705]]


    (iii) Performance evaluation procedures and acceptance criteria 
(e.g., calibrations).
    (2) In your site-specific monitoring plan, you must also address 
paragraphs (c)(2)(i) through (iii) of this section.
    (i) Ongoing operation and maintenance procedures in accordance with 
the general requirements of Sec.  63.8(c)(1), (c)(3), and (c)(4)(ii);
    (ii) Ongoing data quality assurance procedures in accordance with 
the general requirements of Sec.  63.8(d); and
    (iii) Ongoing recordkeeping and reporting procedures in accordance 
with the general requirements of Sec.  63.10(c), (e)(1) and (e)(2)(i).
    (3) You must conduct a performance evaluation of each CMS in 
accordance with your site-specific monitoring plan.
    (4) You must operate and maintain the CMS in continuous operation 
according to the site-specific monitoring plan.
    (d) You must develop and implement a written startup, shutdown, and 
malfunction plan (SSMP) according to the provisions in Sec.  
63.6(e)(3).


Testing and Initial Compliance Requirements




Sec.  63.7510  By what date must I conduct performance tests or other 
initial compliance demonstrations?


    (a) For each existing affected source, you must conduct performance 
tests, set operating limits, and conduct monitoring equipment 
performance evaluations by the compliance date that is specified for 
your source in Sec.  63.7495 and according to the applicable provisions 
in Sec.  63.7(a)(2) as cited in Table 10 to this subpart.
    (b) For each new or reconstructed affected source, you must conduct 
performance tests, set operating limits, and conduct monitoring 
equipment performance evaluations within 180 calendar days after the 
compliance date that is specified for your source in Sec.  63.7495 and 
according to the provisions in Sec.  63.7(a)(2) as cited in Table 10 to 
this subpart.




Sec.  63.7515  When must I conduct subsequent performance tests?


    (a) You must conduct all applicable performance tests according to 
the procedures in Sec.  63.7520 on an annual basis unless you follow 
the requirements listed in paragraphs (b) through (h) of this section. 
The first subsequent performance tests must be completed within 12 
months of the initial performance test but no earlier than 10 months 
after the initial performance test and every 12 months thereafter, 
unless you follow the requirements listed in paragraphs (b) through (h) 
of this section.
    (b) You can conduct performance tests less often for a given 
pollutant if you have test data for at least 3 years, and all stack 
tests for the pollutant (particulate matter, hydrogen chloride, 
mercury, or total selected metals) for over 3 consecutive years show 
that you comply with the emission limit. In this case, you do not have 
to conduct a stack test for that pollutant for the next 2 years. You 
must do a stack test during the third year and no more than 36 months 
following the previous stack test.
    (c) If your boiler or process heater continues to meet the emission 
limit for particulate matter, hydrogen chloride, mercury, or total 
selected metals, you may choose to conduct stack tests for these 
pollutants every third year, but each such test must be within 36 
months of the previous stack test.
    (d) If a stack test shows noncompliance with an emission limit for 
particulate matter, hydrogen chloride, mercury, or total selected 
metals, you must conduct annual stack tests for that pollutant until 
all stack tests over a 3-year period show compliance.
    (e) You are not required to conduct a performance test for total 
selected metals annually if you choose to comply with the alternative 
total selected metals emission limit instead of particulate matter, and 
your operating limit is the total selected metals fuel input. You must 
still meet all applicable continuous compliance requirements in Sec.  
63.7540.
    (f) You are not required to conduct a performance test for hydrogen 
chloride annually if your operating limit for hydrogen chloride is 
chlorine fuel input. You must still meet all applicable continuous 
compliance requirements in Sec.  63.7540.
    (g) You are not required to conduct a performance test for mercury 
annually if your operating limit for mercury is mercury fuel input. You 
must still meet all applicable continuous compliance requirements in 
Sec.  63.7540.
    (h) You must report the results of annual performance tests within 
60 days after the completion of the tests. This report should also 
verify that the operating limits for your affected source have not 
changed or provide documentation of revised operating parameters 
established as specified in Tables 4.A through 4.E to this subpart. The 
reports for all subsequent performance tests should include all 
applicable information required in Sec.  63.7550.




Sec.  63.7520  What performance tests, design evaluations, and other 
procedures must I use?


    (a) You must conduct all performance tests according to Sec.  
63.7(c), (d), (f), and (h). You must also develop a site-specific test 
plan according to the requirements in Sec.  63.7(c).
    (b) You must conduct each performance test in Tables 4.A through 
4.E to this subpart that applies to you.
    (c) For boilers or process heaters in one of the liquid fuel 
subcategories that burn only fossil fuels and other gases and do not 
burn any residual oil, you are not required to conduct a performance 
test to demonstrate compliance with the emission limits.
    (d) You must conduct each performance test under the specific 
conditions listed in Tables 4.A through 4.E to this subpart. You must 
conduct performance tests at the representative process operating 
conditions that are expected to result in the highest emissions of 
hydrogen chloride, particulate matter, and mercury, and you must 
demonstrate initial compliance and establish your operating limits 
based on this test. This requirement could result in the need to 
conduct more than one performance test. If you choose to comply with 
the alternative total selected metals emission limit instead of 
particulate matter, you must conduct all performance tests at the 
representative process operating conditions that are expected to result 
in the highest emissions of hydrogen chloride, total selected metals 
and mercury.
    (e) You may not conduct performance tests during periods of 
startup, shutdown, or malfunction.
    (f) You must conduct three separate test runs for each performance 
test required in this section, as specified in Sec.  63.7(e)(3). Each 
test run must last at least 1 hour.
    (g) To determine compliance with the emission limits, you must use 
the F-Factor methodology and equations in sections 12.2 and 12.3 of EPA 
Method 19 of appendix A of this part to convert the measured 
particulate matter concentrations, the measured hydrogen chloride 
concentrations, the measured total selected metals concentrations, and 
the measured mercury concentrations that result from the initial 
performance test to pound per million British thermal unit (MMBtu) heat 
input emission rates. Method 26A of appendix A of this part must be 
used for the hydrogen chloride performance test for those boilers and 
process heaters with wet scrubbers. All other boilers and process 
heaters must use Method 26 of


[[Page 1706]]


appendix A of this part for the hydrogen chloride performance test.
    (h) For performance tests using Method 5, Method 29, Method 26A and 
Method 17 of appendix A of this part, use Method 1 of appendix A of 
this part to select the sampling location and number of traverse 
points. For Method 26 of appendix A of this part, you must use a 
minimum of three traverse points.
    (i) If you use a control device or combination of control devices 
not covered in Tables 4.A through 4.E to this subpart, or you wish to 
establish and monitor an alternative operating limit, you must apply to 
the Administrator for approval of alternative monitoring under Sec.  
63.8(f).




Sec.  63.7525  What are my monitoring, installation, operation, and 
maintenance requirements?


    (a) Each continuous emissions monitoring system (CEMS) for carbon 
monoxide must be installed, operated, and maintained according to the 
procedures in paragraphs (a)(1) through (4) of this section by the 
compliance date.
    (1) Each CEMS must be installed, operated, and maintained according 
to Performance Specification (PS) 4A of 40 CFR part 60, appendix B, and 
according to the site-specific monitoring plan developed according to 
Sec.  63.7505(c).
    (2) You must conduct a performance evaluation of each CEMS 
according to the requirements in Sec.  63.8 and according to PS 4A of 
40 CFR part 60, appendix B.
    (3) Each CEMS must complete a minimum of one cycle of operation 
(sampling, analyzing, and data recording) for each successive 15-minute 
period.
    (4) The CEMS data must be reduced as specified in Sec.  63.8(g)(2).
    (b) Each continuous opacity monitoring system (COMS) must be 
installed, operated, certified and maintained according to the 
procedures in paragraphs (b)(1) through (7) of this section by the 
compliance date.
    (1) Each COMS must be installed, operated, and maintained according 
to PS 1 of 40 CFR part 60, appendix B.
    (2) You must conduct a performance evaluation of each COMS 
according to the requirements in Sec.  63.8 and according to PS 1 of 40 
CFR part 60, appendix B.
    (3) As specified in Sec.  63.8(c)(4)(i), each COMS must complete a 
minimum of one cycle of sampling and analyzing for each successive 10-
second period and one cycle of data recording for each successive 6-
minute period.
    (4) The COMS data must be reduced as specified in Sec.  63.8(g)(2).
    (5) You must include in your site-specific monitoring plan 
procedures and acceptance criteria for operating and maintaining each 
COMS according to the requirements in Sec.  63.8(d). At a minimum, the 
monitoring plan must include a daily calibration drift assessment, a 
quarterly performance audit, and an annual zero alignment audit of each 
COMS.
    (6) You must operate and maintain each COMS according to the 
requirements in the monitoring plan and the requirements of Sec.  
63.8(e). Identify periods the COMS is out-of-control including any 
periods that the COMS fails to pass a daily calibration drift 
assessment, a quarterly performance audit, or an annual zero alignment 
audit.
    (7) You must determine and record all the 6-minute averages and 3-
hour block averages collected for periods during which the COMS is not 
out-of-control.
    (c) You must install, operate, and maintain each continuous 
parameter monitoring system (CPMS) according to the requirements in 
Sec.  63.8 and the procedures in paragraphs (c)(1) through (5) of this 
section by the compliance date specified in Sec.  63.7495.
    (1) The CPMS must complete a minimum of one cycle of operation for 
each successive 15-minute period. You must have a minimum of four 
successive cycles of operation to have a valid hour of data.
    (2) Except for, monitoring malfunctions, associated repairs and 
required quality assurance or control activities (including, as 
applicable, calibration checks and required zero and span adjustments), 
you must conduct all monitoring in continuous operation at all times 
that the unit is operating. A monitoring malfunction is any sudden, 
infrequent, not reasonably preventable failure of the monitoring system 
to provide valid data. Monitoring failures that are caused in part by 
poor maintenance or careless operation are not malfunctions.
    (3) For purposes of calculating data averages, you must not use 
data recorded during monitoring malfunctions, associated repairs, out-
of-control periods, or required quality assurance or control 
activities. You must use all the data collected during all other 
periods in assessing compliance. Any period for which the monitoring 
system is out-of-control and data are not available for required 
calculations constitutes a deviation from the monitoring requirements.
    (4) Determine the 3-hour block average of all recorded readings, 
except as provided in paragraph (c)(3) of this section.
    (5) Record the results of each inspection, calibration, and 
validation check.
    (d) For the equipment to monitor voltage and secondary current (or 
total power input) of the electrostatic precipitator (ESP), you must 
meet the requirements in paragraphs (c) and (d)(1) and (2) of this 
section.
    (1) Use the ESP manufacturer's installed voltage and secondary 
current monitoring equipment to measure voltage and secondary current 
to the ESP.
    (2) At least monthly, inspect all components of the CPMS for 
integrity and all electrical connections for continuity.
    (e) For the equipment to monitor sorbent injection rate (e.g., 
weigh belt, weigh hopper, or hopper flow measurement device), you must 
meet the requirements in paragraphs (c) and (e)(1) through (4) of this 
section.
    (1) Locate the device in a position(s) that provides a 
representative measurement of the total sorbent injection rate.
    (2) Install and calibrate the device in accordance with 
manufacturer's procedures and specifications.
    (3) At least monthly, inspect all components for integrity and all 
electrical connections for continuity.
    (4) At least annually, calibrate the device in accordance with the 
manufacturer's procedures and specifications.
    (f) If you use a fabric filter to comply with the requirements of 
this subpart, you must install, calibrate, maintain, and continuously 
operate a bag leak detection system as specified in paragraphs (f)(1) 
through (8) of this section.
    (1) You must install and operate a bag leak detection system for 
each exhaust stack of the fabric filter.
    (2) Each bag leak detection system must be installed, operated, 
calibrated, and maintained in a manner consistent with the 
manufacturer's written specifications and recommendations and in 
accordance with the guidance provided in ``Fabric Filter Bag Leak 
Detection Guidance,'' EPA-454/R-98-015, September 1997.
    (3) The bag leak detection system must be certified by the 
manufacturer to be capable of detecting particulate matter emissions at 
concentrations of 10 milligrams per actual cubic meter or less.
    (4) The bag leak detection system sensor must provide output of 
relative or absolute particulate matter loadings.
    (5) The bag leak detection system must be equipped with a device to


[[Page 1707]]


continuously record the output signal from the sensor.
    (6) The bag leak detection system must be equipped with an alarm 
system that will sound automatically when an increase in relative 
particulate matter emissions over a preset level is detected. The alarm 
must be located where it is easily heard by plant operating personnel.
    (7) For positive pressure fabric filter systems, a bag leak 
detection system must be installed in each baghouse compartment or 
cell. For negative pressure or induced air fabric filters, the bag leak 
detector must be installed downstream of the fabric filter.
    (8) Where multiple detectors are required, the system's
    instrumentation and alarm may be shared among detectors.




Sec.  63.7530  How do I demonstrate initial compliance with the 
emission limitations and work practice standards?


    (a) You must demonstrate initial compliance with each emission 
limitation and work practice standard that applies to you according to 
Tables 5.A through 5.E and 6 to this subpart.
    (b) For new or reconstructed boilers or process heaters in one of 
the liquid fuel subcategories that burn only fossil fuels and other 
gases and do not burn any residual oil, you are not required to conduct 
a performance test to demonstrate compliance with the emission limits.
    (1) To demonstrate initial compliance, you must include a signed 
statement in the Notification of Compliance Status report required in 
Sec.  63.7545(e) that indicates you burn only liquid fossil fuels other 
than residual oils either alone or in combination with gaseous fuels.
    (2) You must also keep records, as required in Sec.  63.7555, that 
demonstrate that you burn only liquid fossil fuels other than residual 
oils either alone or in combination with gaseous fuels.
    (c) You must establish each site-specific operating limit in Tables 
2.A and 2.B to this subpart that applies to you according to the 
requirements in Sec.  63.7520, Tables 4.A through 4.E to this subpart, 
and paragraphs (c)(1) through (6) of this section, as applicable.
    (1) If you do not use a wet or dry scrubber, you must set your 
operating limit for hydrogen chloride emissions based on the chlorine 
fuel input established during the initial performance test according to 
the procedures in paragraphs (c)(1)(i) and (ii) of this section.
    (i) During the initial performance test for hydrogen chloride, you 
must measure the average hourly fuel input, average chlorine 
concentration, and average heat input of each fuel burned during the 3-
hour performance test.
    (ii) You must set your operating limit for hydrogen chloride using 
Equation 1 of this section:
[GRAPHIC] [TIFF OMITTED] TP13JA03.000


Where:


Clinput = Average amount of chlorine entering the boiler or 
process heater through fuels burned in units of pounds per Btu. This is 
the operating limit.
Ci = Average concentration of chlorine in fuel, i, during 
each of the three 1-hour test periods as measured using the test 
methods specified in Tables 4.C and 4.D to this subpart, in units of 
pound per pound for solid fuels, pounds per gallon for liquid fuels, or 
pound per dry standard cubic foot for gaseous fuels.
Qi = Average hourly input of fuel, i, during each of the 
three 1-hour test periods in units of pound per hour for solid fuels, 
gallons per hour for liquid fuels, or dry standard cubic feet per hour 
for gaseous fuels. If you do not burn multiple fuels during the 
performance test, it is not necessary to determine the value of this 
term. Insert a value of ``1'' for Qi.
Hv,i = Average heat input of fuel, i, during each of the 
three 1-hour test periods in units of Btu per hour as measured by the 
test methods indicated in Tables 4.C and 4.D to this subpart.
n = Number of different fuel types in the worst-case fuel input stream 
burned during each of the three 1-hour performance tests.


    (2) If you do not use a wet scrubber, you must establish an opacity 
operating limit during the initial performance test for particulate 
matter or total selected metals and mercury. This opacity level must 
not exceed 20 percent.
    (3) If you use a wet scrubber and you conduct separate performance 
tests for particulate matter, hydrogen chloride, and mercury emissions, 
you must establish one set of operating limits for pH, liquid flow-
rate, and pressure drop. The pH must be the level established during 
the hydrogen chloride performance test. The liquid flow-rate and 
pressure drop operating limits must be the highest of the values 
established during the performance tests.
    (4) If you do not use a control device or do not want to take 
credit for the control device and you choose to comply with the 
alternative total selected metals emission limit instead of particulate 
matter, you must set your operating limit for total selected metals 
emissions based on the metals fuel input established during the initial 
performance test according to the procedures in paragraphs (c)(4)(i) 
and (ii) of this section.
    (i) During the initial performance test for total selected metals, 
you must measure the average hourly fuel input if you burn a 
combination of multiple fuels, average total selected metals 
concentration of the fuel input, and average heat input of each fuel 
burned during the 3-hour performance test.
    (ii) You must set your operating limit for total selected metals 
using Equation 2 of this section:
[GRAPHIC] [TIFF OMITTED] TP13JA03.001


Where:


Metalsinput = Average amount of total selected metals 
entering the boiler or process heater through fuels burned in units of 
pounds per Btu. This is the operating limit.
Mi = Average concentration of total selected metals in fuel, 
i, during each of the three 1-hour test periods as measured using the 
test methods specified in Table 4.E to this subpart, in units of pound 
per pound for solid fuels, pound per gallon for liquid fuels, or pound 
per dry standard cubic foot for gaseous fuels.
Qi = Average hourly input of fuel, i, during each of the 
three 1-hour test periods in units of pounds per hour for solid fuels, 
gallons per hour for liquid fuels, or dry standard cubic feet per hour 
for gaseous fuels. If you do not burn multiple fuels during the 
performance test, it is


[[Page 1708]]


not necessary to determine the value of this term. Insert a value of 
``1'' for Qi.
Hv,i = Average heat input of fuel, i, during each of the 
three 1-hour test periods in units of Btu per hour as measured by the 
test methods indicated in Table 4.E to this subpart.
n = Number of different fuel types in the worst-case fuel input stream 
burned during the 3-hour performance test.


    (5) If you do not use a control device or do not want to take 
credit for the control device, you must set your operating limit for 
mercury emissions based on the mercury fuel input established during 
the initial performance test according to the procedures in paragraphs 
(c)(5)(i) and (ii) of this section.
    (i) During the initial performance test for mercury, you must 
measure the average hourly fuel input if you burn a combination of 
multiple fuels, average mercury concentration of the fuel input, and 
average heat input of each fuel burned during the 3-hour performance 
test.
    (ii) You must set your operating limit for mercury using Equation 3 
of this section:
[GRAPHIC] [TIFF OMITTED] TP13JA03.002


Where:


Mercuryinput = Average amount of mercury entering the boiler 
or process heater through fuels burned in units of pounds per Btu. This 
is the operating limit.
HGi = Average concentration of mercury in fuel, i, during 
each of the three 1-hour test periods as measured using the test 
methods specified in Table 4.E to this subpart, in units of pound per 
pound for solid fuels, pound per gallon for liquid fuels, or pound per 
dry standard cubic foot for gaseous fuels.
Qi = Average hourly input of fuel, i, during each of the 
three 1-hour test periods in units of pounds per hour for solid fuels, 
gallons per hour for liquid fuels, or dry standard cubic feet per hour 
for gaseous fuels. If you do not burn multiple fuels during the 
performance test, it is not necessary to determine the value of this 
term. Insert a value of ``1'' for Qi.
Hv,i = Average heat input of fuel, i, during each of the 
three 1-hour test periods in units of Btu per hour as measured by the 
test methods indicated in Table 4.E to this subpart.
n = Number of different fuel types in the worst-case fuel input stream 
burned during the 3-hour performance test.


    (6) You must establish parameter operating limits according to 
paragraphs (c)(6)(i) through (v) of this section.
    (i) To establish an opacity operating limit, you must set the 
maximum opacity operating limit equal to the maximum 1-hour average 
opacity value measured during the three-run performance test for 
particulate matter or total selected metals and mercury, or 20 percent, 
whichever is lower.
    (ii) To establish operating limits for a wet scrubber, you must set 
the minimum operating limits for pH, liquid flow-rate, and pressure 
drop equal to the minimum 1-hour average values measured during the 
three-run performance test.
    (iii) To establish operating limits for an electrostatic 
precipitator, you must set the minimum operating limits for voltage and 
secondary current (or total power input) equal to the minimum 1-hour 
average values measured during the three-run performance test.
    (iv) To establish operating limits for a dry scrubber, you must set 
the minimum sorbent injection rate operating limit equal to the minimum 
1-hour average value measured during the three-run performance test.
    (v) The operating limit for fabric filters requires that a bag leak 
detection system be installed according to the requirements in Sec.  
63.7525, and that each fabric filter must be operated such that the bag 
leak detection system alarm does not sound more than 5 percent of the 
operating time during a 6-month period.
    (d) You must submit the Notification of Compliance Status report 
containing the results of the initial compliance demonstration 
according to the requirements in Sec.  63.7545(e).


Continuous Compliance Requirements




Sec.  63.7535  How do I monitor and collect data to demonstrate 
continuous compliance?


    (a) You must monitor and collect data according to this section.
    (b) Except for monitor malfunctions, associated repairs, and 
required quality assurance or control activities (including, as 
applicable, calibration checks and required zero and span adjustments), 
you must monitor continuously (or collect data at all required 
intervals) at all times that the affected source is operating.
    (c) You may not use data recorded during monitoring malfunctions, 
associated repairs, or required quality assurance or control 
activities, in data averages and calculations used to report emission 
or operating levels. You must use all the data collected during all 
other periods in assessing the operation of the control device and 
associated control system.




Sec.  63.7540  How do I demonstrate continuous compliance with the 
emission limitations and work practice standards?


    (a) You must demonstrate continuous compliance with each emission 
limit, operating limit, and work practice standard in Tables 1 through 
3 to this subpart that applies to you according to the methods 
specified in Tables 7.A, 7.B, and 8 to this subpart and paragraphs 
(a)(1) through (9) of this section.
    (1) For affected sources electing to comply with an emission limit 
based on fuel analysis, you must keep records of all fuels burned in 
each boiler or process heater during the reporting period to 
demonstrate that all fuels used would result in lower emissions of 
particulate matter or total selected metals, lower emissions of 
hydrogen chloride, and lower emissions of mercury than the emissions 
from the worst-case fuel input that was burned during the initial 
performance test. You must also keep records that demonstrate that all 
fuels burned during the reporting period were obtained from the same 
suppliers as those fuels burned during the performance test.
    (2) For new or reconstructed boilers or process heaters in one of 
the liquid fuel subcategories that burn only fossil fuels and other 
gases and do not burn any residual oil, you are not required to set and 
maintain operating limits to demonstrate continuous compliance with the 
emission limits. To demonstrate continuous compliance with the emission 
limits, you must include a signed statement in each semiannual 
compliance report required in Sec.  63.7550 that indicates you burned




[[Continued on page 1709]]


From the Federal Register Online via GPO Access [wais.access.gpo.gov]
]                         
 
[[pp. 1709-1758]] National Emission Standards for Hazardous Air Pollutants for 
Industrial/Commercial/Institutional Boilers and Process Heaters


[[Continued from page 1708]]


[[Page 1709]]


only liquid fossil fuels other than residual oils, either alone or in 
combination with gaseous fuels, during the reporting period; and you 
must also keep records, as required in paragraph (a)(1) of this section 
and Sec.  63.7555, that demonstrate that you burn only liquid fossil 
fuels other than residual oils, either alone or in combination with 
gaseous fuels.
    (3) If you plan to burn a new type of fuel, a fuel from a new 
supplier, or a new mixture of fuels and your operating limit for 
hydrogen chloride is chlorine input, you must demonstrate continuous 
compliance by recalculating the chlorine input using Equation 1 of 
Sec.  63.7530 according to the procedures specified in paragraphs 
(a)(3)(i) through (iii) of this section.
    (i) Determine for any new fuel the heating value and the chlorine 
concentration, based on supplier data or own fuel analysis, according 
to the provisions in the site-specific test plan developed according to 
the requirements in Sec.  63.7520(a).
    (ii) Estimate the maximum hourly input at which each fuel will be 
burned.
    (iii) Recalculate the amount of chlorine that would be put into the 
boiler or process heater during an hour under these new conditions 
using Equation 1 of Sec.  63.7530.
    (4) If you plan to burn a new type of fuel, a fuel from a new 
supplier or a new mixture of fuels, your operating limit for hydrogen 
chloride is chlorine input, and the results of recalculating the 
chlorine input using Equation 1 of Sec.  63.7530 are higher than the 
chlorine input operating limit established during the initial 
performance test, then you must conduct a new performance test 
according to the procedures in Sec.  63.7520 to demonstrate that the 
hydrogen chloride emissions do not exceed the emission limitation. You 
must also establish a new operating limit based on this performance 
test according to the procedures in Sec.  63.7530(c).
    (5) If you plan to burn a new type of fuel, a fuel from a new 
supplier, or a new mixture of fuels and you choose to comply with the 
alternative total selected metals emission limit instead of particulate 
matter and your operating limit is the total selected metals fuel 
content, you must demonstrate continuous compliance with your operating 
limit by recalculating the total selected metals input using Equation 2 
of Sec.  63.7530 according to the procedures specified in paragraphs 
(a)(5)(i) through (iii) of this section.
    (i) Determine for any new fuel the heating value and the total 
selected metals concentration, based on supplier data or own fuel 
analysis, according to the provisions in the site-specific test plan 
developed according to the requirements in Sec.  63.7520(a).
    (ii) Estimate the maximum hourly input at which each fuel will be 
burned.
    (iii) Recalculate the amount of total selected metals that would be 
put into the boiler or process heater during an hour under these new 
conditions using Equation 2 of Sec.  63.7530.
    (6) If you plan to burn a new type of fuel, a fuel from a new 
supplier or a new mixture of fuels, you choose to comply with the 
alternative total selected metals emission limit instead of particulate 
matter, and the results of recalculating the total selected metals 
input using Equation 2 of Sec.  63.7530 are higher than the total 
selected metals operating limit established during the initial 
performance test, then you must conduct a new performance test 
according to the procedures in Sec.  63.7520 to demonstrate that the 
total selected metals emissions do not exceed the emission limit. You 
must also establish a new operating limit based on this performance 
test according to the procedures in Sec.  63.7530(c).
    (7) If you plan to burn a new type of fuel, a fuel from a new 
supplier, or a new mixture of fuels and your operating limit for 
mercury emissions is the mercury fuel content, you must demonstrate 
continuous compliance with your operating limit by recalculating the 
mercury input using Equation 3 of Sec.  63.7530 according to the 
procedures specified in paragraphs (a)(7)(i) through (iii) of this 
section.
    (i) Determine for any new fuel the heating value and the mercury 
concentration, based on supplier data or own fuel analysis, according 
to the provisions in the site-specific test plan developed according to 
the requirements in Sec.  63.7520(a).
    (ii) Estimate the maximum hourly input at which each fuel will be 
burned.
    (iii) Recalculate the amount of mercury that would be put into the 
boiler or process heater during an hour under these new conditions 
using Equation 3 of Sec.  63.7530.
    (8) If you plan to burn a new type of fuel, a fuel from a new 
supplier or a new mixture of fuels, and the results of recalculating 
the mercury input using Equation 3 of Sec.  63.7530 are higher than the 
mercury operating limit established during the initial performance 
test, then you must conduct a new performance test according to the 
procedures in Sec.  63.7520 to demonstrate that the mercury emissions 
do not exceed the emission limit. You must also establish a new 
operating limit based on this performance test according to the 
procedures in Sec.  63.7530(c).
    (9) If your unit is controlled with a fabric filter, you must 
demonstrate continuous compliance with the operating limits for fabric 
filters by operating each fabric filter system such that the bag leak 
detection system does not sound more than 5 percent of the operating 
time during a 6-month period and by keeping records of the date, time, 
and duration of each alarm, the time corrective action was initiated 
and completed, a brief description of the cause of the alarm and the 
corrective action taken. You must also record the percent of the 
operating time during each 6-month period that the alarm sounds. In 
calculating this operating time percentage, if inspection of the fabric 
filter demonstrates that no corrective action is required, no alarm 
time is counted. If corrective action is required, each alarm shall be 
counted as a minimum of 1 hour. If you take longer than 1 hour to 
initiate corrective action, the alarm time shall be counted as the 
actual amount of time taken to initiate corrective action.
    (b) You must report each instance in which you did not meet each 
emission limit and each operating limit in Tables 7.A and 7.B to this 
subpart that apply to you. This includes periods of startup, shutdown, 
and malfunction. You must also report each instance in which you did 
not meet the work practice requirements in Table 8 to this subpart that 
apply to you. These instances are deviations from the emission 
limitations and work practice standards in this subpart. These 
deviations must be reported according to the requirements in Sec.  
63.7550.
    (c) During periods of startup, shutdown, and malfunction, you must 
operate in accordance with the startup, shutdown, and malfunction plan 
as required in Sec.  63.7505(d).
    (d) Consistent with Sec. Sec.  63.6(e) and 63.7(e)(1), deviations 
that occur during a period of startup, shutdown, or malfunction are not 
violations if you demonstrate to the Administrator's satisfaction that 
you were operating in accordance with the startup, shutdown, and 
malfunction plan. The Administrator will determine whether deviations 
that occur during a period of startup, shutdown, or malfunction are 
violations, according to the provisions in Sec.  63.6(e).


Notifications, Reports, and Records




Sec.  63.7545  What notifications must I submit and when?


    (a) You must submit all of the notifications in Sec. Sec.  
63.6(h)(4) and (5), 63.7(b) and (c), 63.8 (e), 63.8(f)(4) and


[[Page 1710]]


(6), and 63.9 (b) through (h) that apply to you by the dates specified.
    (b) As specified in Sec.  63.9(b)(2), if you startup your affected 
source before [DATE OF PUBLICATION OF THE FINAL RULE IN THE FEDERAL 
REGISTER], you must submit an Initial Notification not later than 120 
calendar days after [DATE THE FINAL RULE IS PUBLISHED IN THE FEDERAL 
REGISTER]. The Initial Notification must include the information 
required in paragraphs (b)(1) and (2) of this section, as applicable.
    (1) If your affected source has an annual capacity factor of 
greater than 10 percent, your Initial Notification must include the 
information required by Sec.  63.9(b)(2).
    (2) If your affected source has a federally enforceable permit that 
limits the annual capacity factor to less than or equal to 10 percent 
such that the unit is in one of the limited use subcategories (the 
limited use solid fuel subcategory, the limited use liquid fuel 
subcategory, or the limited use gaseous fuel subcategory), your Initial 
Notification must include the information required by Sec.  63.9(b)(2) 
and also a signed statement indicating your affected source has a 
federally enforceable permit that limits the annual capacity factor to 
less than or equal to 10 percent.
    (c) As specified in Sec.  63.9(b)(3), if you startup your new or 
reconstructed affected source on or after [DATE THE FINAL RULE IS 
PUBLISHED IN THE FEDERAL REGISTER], you must submit an Initial 
Notification not later than 120 calendar days after you become subject 
to this subpart. The Initial Notification must include the information 
required in paragraphs (c)(1) and (2) of this section, as applicable.
    (1) If your affected source has an annual capacity factor of 
greater than 10 percent, your Initial Notification must include the 
information required by Sec.  63.9(b)(3).
    (2) If your affected source has a federally enforceable permit that 
limits the annual capacity factor to less than or equal to 10 percent 
such that the unit is in one of the limited use subcategories, your 
Initial Notification must include the information required by Sec.  
63.9(b)(3) and also a signed statement indicating your affected source 
has a federally enforceable permit that limits the annual capacity 
factor to less than or equal to 10 percent.
    (d) If you are required to conduct a performance test, you must 
submit a notification of intent to conduct a performance test at least 
60 calendar days before the performance test is scheduled to begin as 
required in Sec.  63.7(b)(1).
    (e) If you are required to conduct a performance test or other 
initial compliance demonstration as specified in Tables 4.A through 
4.E, 5.A through 5.E, or 6 to this subpart, you must submit a 
Notification of Compliance Status report according to Sec.  
63.9(h)(2)(ii) and the requirements specified in paragraphs (e)(1)(i) 
through (e)(1)(vii) of this section.
    (1) For each initial compliance demonstration, you must submit the 
Notification of Compliance Status report, including all performance 
test results, before the close of business on the 60th calendar day 
following the completion of the performance test and/or other initial 
compliance demonstrations according to Sec.  63.10(d)(2). The 
Notification of Compliance Status report must contain all the 
information specified in paragraphs (e)(l)(i) through (vii) of this 
section, as applicable.
    (i) A description of the affected source(s) including 
identification of which subcategory the source is in, the capacity of 
the source, a description of the add-on controls used on the source 
description of the fuel(s) burned, and justification for the worst-case 
fuel burned during the performance test.
    (ii) Summary of the results of all performance tests, fuel 
analyses, and calculations conducted to demonstrate initial compliance 
including all established operating limits.
    (iii) Identification of whether you are complying with the 
particulate matter emission limit or the alternative total selected 
metals emission limit.
    (iv) A signed certification that you have met all applicable 
emission limitations and work practice standards.
    (v) A summary of the carbon monoxide emissions monitoring data 
recorded during the performance test to show that you have met the work 
practice standard in Table 6 to this subpart, if applicable.
    (vi) If your new or reconstructed boiler or process heater is in 
one of the liquid fuel subcategories and burns only liquid fossil fuels 
other than residual oil either alone or in combination with gaseous 
fuels, you must submit a signed statement certifying this in your 
Notification of Compliance Status report.
    (vii) If you had a deviation from any emission limitation or work 
practice standard, you must also submit a description of the deviation, 
the duration of the deviation, and the corrective action taken in the 
Notification of Compliance Status report.




Sec.  63.7550  What reports must I submit and when?


    (a) You must submit each report in Table 9 to this subpart that 
applies to you.
    (b) Unless the Administrator has approved a different schedule for 
submission of reports under Sec.  63.10(a), you must submit each report 
by the date in Table 9 to this subpart and according to the 
requirements in paragraphs (b)(1) through (5) of this section.
    (1) The first compliance report must cover the period beginning on 
the compliance date that is specified for your affected source in Sec.  
63.7495 and ending on June 30 or December 31, whichever date is the 
first date following the end of the first calendar half after the 
compliance date that is specified for your source in Sec.  63.7495.
    (2) The first compliance report must be postmarked or delivered no 
later than July 31 or January 31, whichever date is the first date 
following the end of the first calendar half after the compliance date 
that is specified for your source in Sec.  63.7495.
    (3) Each subsequent compliance report must cover the semiannual 
reporting period from January 1 through June 30 or the semiannual 
reporting period from July 1 through December 31.
    (4) Each subsequent compliance report must be postmarked or 
delivered no later than July 31 or January 31, whichever date is the 
first date following the end of the semiannual reporting period.
    (5) For each affected source that is subject to permitting 
regulations pursuant to 40 CFR part 70 or 40 CFR part 71, and if the 
permitting authority has established dates for submitting semiannual 
reports pursuant to 40 CFR 70.6(a)(3)(iii)(A) or 40 CFR 
71.6(a)(3)(iii)(A), you may submit the first and subsequent compliance 
reports according to the dates the permitting authority has established 
instead of according to the dates in paragraphs (b) (1) through (4) of 
this section.
    (c) The compliance report must contain the information required in 
paragraphs (c) (1) through (11) of this section.
    (1) Company name and address.
    (2) Statement by a responsible official with that official's name, 
title, and signature, certifying the truth, accuracy, and completeness 
of the content of the report.
    (3) Date of report and beginning and ending dates of the reporting 
period.
    (4) The total fuel use by each affected source electing to comply 
with an emission limit based on fuel analysis for each calendar month 
within the


[[Page 1711]]


semiannual reporting period including, but not limited to, a 
description of the fuel, the total fuel usage amount with units of 
measure, and information on the supplier of the fuel and original 
source location of the fuel.
    (5) A summary of the results of the annual performance tests and 
documentation of any operating limits that were reestablished during 
this test, if applicable.
    (6) A signed statement indicating that you burned no new types of 
fuel, no fuels from a new supplier, or no new fuel mixture. Or, if you 
did burn a new type of fuel, a fuel from a new supplier, or a new fuel 
mixture and your operating limit for hydrogen chloride is fuel chlorine 
input, you must submit the calculation of chlorine input, using 
Equation 1 of Sec.  63.7530, that demonstrates that your source is 
still within its operating limit for hydrogen chloride emissions. If 
you burned a new type of fuel, fuel from a new supplier, or a new fuel 
mixture and your operating limit for the alternative total selected 
metals emission limit is fuel total selected metals input, you must 
submit the calculation of total selected metals input, using Equation 2 
of Sec.  63.7530, that demonstrates that your source is still within 
its operating limit for total selected metals emissions. If you burned 
a new type of fuel, fuel from a new supplier, or a new fuel mixture and 
your operating limit for mercury is fuel mercury input, you must submit 
the calculation of mercury input, using Equation 3 of Sec.  63.7530, 
that demonstrates that your source is still within its operating limit 
for mercury emissions.
    (7) If you wish to burn a new type of fuel, a fuel from a new 
supplier, or a new fuel mixture, and you cannot demonstrate compliance 
with the hydrogen chloride operating limit using Equation 1 of Sec.  
63.7530, the total selected metals operating limit using Equation 2 of 
Sec.  63.7530, or the mercury operating limit using Equation 3 of Sec.  
63.7530, you must include in the compliance report a statement 
indicating the intent to conduct a new performance test under the new 
worst-case conditions.
    (8) The average daily hours of operation by each source for each 
calendar month within the semiannual reporting period.
    (9) If you had a startup, shutdown, or malfunction during the 
reporting period and you took actions consistent with your startup, 
shutdown, and malfunction plan, the compliance report must include the 
information in Sec.  63.10(d)(5)(i).
    (10) If there are no deviations from any emission limitations 
(emission limits or operating limits) in this subpart that apply to you 
and there are no deviations from the requirements for work practice 
standards in Table 8 to this subpart, a statement that there were no 
deviations from the emission limitations or work practice standards 
during the reporting period.
    (11) If there were no periods during which the CMS, including CEMS, 
COMS, and CPMS, were out-of-control as specified in Sec.  63.8(c)(7), a 
statement that there were no periods during which the CMS were out-of-
control during the reporting period.
    (d) For each deviation from an emission limitation (emission limits 
or operating limits) in this subpart and for each deviation from the 
requirements for work practice standards in Table 8 to this subpart 
that occurs at an affected source where you are not using CMS to comply 
with that emission limitation or work practice standard, the compliance 
report must contain the information in paragraphs (c) (1) through (11) 
of this section and the information required in paragraphs (d) (1) 
through (4) of this section. This includes periods of startup, 
shutdown, and malfunction.
    (1) The total operating time of each affected source during the 
reporting period.
    (2) A description of the deviation and which limitation you 
deviated from.
    (3) Information on the number, duration, and cause of deviations 
(including unknown cause), as applicable, and the corrective action 
taken.
    (4) A copy of the test report if the annual performance test showed 
a deviation from the emission limit for particulate matter or the 
alternative total selected metals limit, a deviation from the hydrogen 
chloride emission limit, or a deviation from the mercury emission 
limit.
    (e) For each deviation from an emission limitation (emission 
limitation and operating limit) or work practice standard in this 
subpart occurring at an affected source where you are using a CMS to 
comply with that emission limitation or work practice standard, you 
must include the information in paragraphs (c) (1) through (11) of this 
section and the information required in paragraphs (e) (1) through (12) 
of this section. This includes periods of startup, shutdown, and 
malfunction and any deviations from your site-specific monitoring plan 
as required in Sec.  63.7505(c).
    (1) The date and time that each malfunction started and stopped and 
description of the nature of the deviation (i.e., what you deviated 
from).
    (2) The date and time that each CMS was inoperative, except for 
zero (low-level) and high-level checks.
    (3) The date, time, and duration that each CMS was out-of-control, 
including the information in Sec.  63.8(c)(8).
    (4) The date and time that each deviation started and stopped, and 
whether each deviation occurred during a period of startup, shutdown, 
or malfunction or during another period.
    (5) A summary of the total duration of the deviation during the 
reporting period and the total duration as a percent of the total 
source operating time during that reporting period.
    (6) A breakdown of the total duration of the deviations during the 
reporting period into those that are due to startup, shutdown, control 
equipment problems, process problems, other known causes, and other 
unknown causes.
    (7) A summary of the total duration of CMS downtime during the 
reporting period and the total duration of CMS downtime as a percent of 
the total source operating time during that reporting period.
    (8) An identification of each parameter that was monitored at the 
affected source for which there was a deviation, including opacity, 
carbon monoxide, and operating parameters for wet scrubbers and other 
control devices.
    (9) A brief description of the source for which there was a 
deviation.
    (10) A brief description of each CMS for which there was a 
deviation.
    (11) The date of the latest CMS certification or audit for the 
system for which there was a deviation.
    (12) A description of any changes in CMSs, processes, or controls 
since the last reporting period for the source for which there was a 
deviation.
    (f) Each affected source that has obtained a title V operating 
permit pursuant to 40 CFR part 70 or 40 CFR part 71 must report all 
deviations as defined in this subpart in the semiannual monitoring 
report required by 40 CFR 70.6(a)(3)(iii)(A) or 40 CFR 
71.6(a)(3)(iii)(A). If an affected source submits a compliance report 
pursuant to Table 9 to this subpart along with, or as part of, the 
semiannual monitoring report required by 40 CFR 70.6(a)(3)(iii)(A) or 
40 CFR 71.6(a)(3)(iii)(A), and the compliance report includes all 
required information concerning deviations from any emission limitation 
(including any operating limit), or work practice standard in this 
subpart, submission of the compliance report satisfies any obligation 
to report the same deviations in the semiannual monitoring report.


[[Page 1712]]


However, submission of a compliance report does not otherwise affect 
any obligation the affected source may have to report deviations from 
permit requirements to the permit authority.




Sec.  63.7555  What records must I keep?


    (a) You must keep records according to paragraphs (a) (1) through 
(3) of this section.
    (1) A copy of each notification and report that you submitted to 
comply with this subpart, including all documentation supporting any 
Initial Notification or Notification of Compliance Status or semiannual 
compliance report that you submitted, according to the requirements in 
Sec.  63.10(b)(2)(xiv).
    (2) The records in Sec.  63.6(e)(3)(iii) through (v) related to 
startup, shutdown, and malfunction.
    (3) Records of performance tests or other compliance 
demonstrations, performance evaluations, and opacity observations as 
required in Sec.  63.10(b)(2)(viii).
    (b) For each CEMS, CPMS, and COMS, you must keep records according 
to paragraphs (b) (1) through (5) of this section.
    (1) Records described in Sec.  63.10(b)(2) (vi) through (xi).
    (2) Monitoring data for COMS during a performance evaluation as 
required in Sec.  63.6(h)(7) (i) and (ii).
    (3) Previous (i.e., superseded) versions of the performance 
evaluation plan as required in Sec.  63.8(d)(3).
    (4) Request for alternatives to relative accuracy test for CEMS as 
required in Sec.  63.8(f)(6)(i).
    (5) Records of the date and time that each deviation started and 
stopped, and whether the deviation occurred during a period of startup, 
shutdown, or malfunction or during another period.
    (c) You must keep the records required in Tables 7.A, 7.B, and 8 to 
this subpart including records of all monitoring data and calculated 
averages for applicable operating limits such as opacity, pressure 
drop, carbon monoxide, and pH to show continuous compliance with each 
emission limitation, operating limit and work practice standard that 
applies to you.
    (d) You must also keep the records in paragraphs (d) (1) through 
(5) of this section.
    (1) You must keep records of daily fuel use by each source electing 
to comply with an emission limit based on fuel analysis, including the 
type(s) of fuel, amount(s) used, and the supplier(s) and original 
source location(s).
    (2) You must keep records of daily hours of operation by each 
source.
    (3) A copy of all calculations and supporting documentation of 
chlorine fuel input, using Equation 1 of Sec.  63.7530, that were done 
to demonstrate continuous compliance with the hydrogen chloride 
emission limitation. Supporting documentation should include results of 
any fuel analyses and basis for the estimates of maximum fuel input.
    (4) A copy of all calculations and supporting documentation of 
total selected metals fuel input, using Equation 2 of Sec.  63.7530, 
that were done to demonstrate continuous compliance with the total 
selected metals emission limitation. Supporting documentation should 
include results of any fuel analyses and basis for the estimates of 
maximum fuel input.
    (5) A copy of all calculations and supporting documentation of 
mercury fuel input, using Equation 3 of Sec.  63.7530, that were done 
to demonstrate continuous compliance with the mercury emission 
limitation. Supporting documentation should include results of any fuel 
analyses and basis for the estimates of maximum fuel input.
    (e) If your boiler or process heater has a federally enforceable 
permit that limits the annual capacity factor to less than or equal to 
10 percent such that the unit is in one of the limited use 
subcategories, you must keep the records in paragraphs (e) (1) and (2) 
of this section.
    (1) A copy of the federally enforceable permit that limits the 
annual capacity factor of the source to less than or equal to 10 
percent.
    (2) Fuel use records for the days the boiler or process heater was 
operating.




Sec.  63.7560  In what form and how long must I keep my records?


    (a) Your records must be in a form suitable and readily available 
for expeditious review, according to Sec.  63.10(b)(1).
    (b) As specified in Sec.  63.10(b)(1), you must keep each record 
for 5 years following the date of each occurrence, measurement, 
maintenance, corrective action, report, or record.
    (c) You must keep each record on site for at least 2 years after 
the date of each occurrence, measurement, maintenance, corrective 
action, report, or record, according to Sec.  63.10(b)(1). You can keep 
the records offsite for the remaining 3 years.


Other Requirements and Information




Sec.  63.7565  What parts of the General Provisions apply to me?


    Table 10 to this subpart shows which parts of the General 
Provisions in Sec. Sec.  63.1 through 63.15 apply to you.




Sec.  63.7570  Who implements and enforces this subpart?


    (a) This subpart can be implemented and enforced by the U.S. EPA, 
or a delegated authority such as your State, local, or tribal agency. 
If the Administrator has delegated authority to your State, local, or 
tribal agency, then that agency has the authority to implement and 
enforce this subpart. You should contact your EPA Regional Office to 
find out if this subpart is delegated to your State, local, or tribal 
agency.
    (b) In delegating implementation and enforcement authority to this 
subpart to a State, local, or tribal agency under 40 CFR part 63, 
subpart E, the authorities contained in paragraph (c) of this section 
are retained by the Administrator and are not transferred to the State, 
local, or tribal agency. The U.S. EPA retains oversight of this rule 
and can take enforcement actions, as appropriate.
    (c) The authorities that will not be delegated to State, local, or 
tribal agencies are listed in paragraphs (c)(1) through (5) of this 
section.
    (1) Approval of alternatives to the non-opacity emission limits and 
work practice standards in Sec.  63.7500(a) through (c) under Sec.  
63.6(g).
    (2) Approval of alternative opacity emission limits in Sec.  
63.7500(a) under Sec.  63.6(h)(9).
    (3) Approval of major alternatives to test methods under Sec.  
63.7(e)(2)(ii) and (f) and as defined in Sec.  63.90.
    (4) Approval of major alternatives to monitoring under Sec.  
63.8(f) and as defined in Sec.  63.90.
    (5) Approval of major alternatives to recordkeeping and reporting 
under Sec.  63.10(f) and as defined in Sec.  63.90.




Sec.  63.7575  What definitions apply to this subpart?


    Terms used in this subpart are defined in the Clean Air Act, in 
Sec.  63.2, and in this section as follows:
    Annual capacity factor means the ratio between the actual heat 
input to a boiler or process heater from the fuels burned during a 
calendar year and the potential heat input to the boiler or process 
heater had it been operated for 8,760 hours during a calendar year at 
the maximum steady state design heat input capacity.
    Bag leak detection system means an instrument that is capable of 
monitoring particulate matter loadings in the exhaust of a fabric 
filter (i.e., baghouse) in order to detect bag failures. A bag leak 
detection system includes, but is not limited to, an instrument that 
operates on electrodynamic, triboelectric, light scattering, light


[[Page 1713]]


transmittance, or other principle to monitor relative particulate 
matter loadings.
    Biomass fuel means wood, wood residue, and wood products (e.g., 
trees, tree stumps, tree limbs, bark, lumber, sawdust, sanderdust, 
chips, scraps, slabs, millings, and shavings); vegetative agricultural 
and silvicultural materials, such as logging residues (slash), nut and 
grain hulls and chaff (e.g., almond, walnut, peanut, rice, and wheat), 
bagasse, orchard prunings, corn stalks, coffee bean hulls and grounds.
    Boiler means an enclosed device using controlled flame combustion 
and having the primary purpose of recovering thermal energy in the form 
of steam or hot water. Waste heat boilers are excluded from this 
definition.
    Coal means all solid fuels classifiable as anthracite, bituminous, 
sub-bituminous, or lignite by the American Society for Testing and 
Materials in ASTM D388-77, ``Standard Specification for Classification 
of Coals by Rank,'' coal refuse, and petroleum coke. Synthetic fuels 
derived from coal for the purpose of creating useful heat including, 
but not limited to, solvent-refined coal, coal-oil mixtures, and coal-
water mixtures, are included in this definition for the purposes to 
this subpart.
    Coal refuse means any by-product of coal mining or coal cleaning 
operations with an ash content greater than 50 percent (by weight) and 
a heating value less than 13,900 kilojoules per kilogram (6,000 Btu per 
pound) on a dry basis.
    Commercial/Institutional boiler means a boiler used in commercial 
establishments or institutional establishments such as medical centers, 
research centers, institutions of higher education, hotels, and 
laundries to provide electricity, steam, and/or hot water.
    Deviation means any instance in which an affected source subject to 
this subpart, or an owner or operator of such a source:
    (1) Fails to meet any requirement or obligation established by this 
subpart including, but not limited to, any emission limitation 
(including any operating limit) or work practice standard;
    (2) Fails to meet any term or condition that is adopted to 
implement an applicable requirement in this subpart and that is 
included in the operating permit for any affected source required to 
obtain such a permit; or
    (3) Fails to meet any emission limitation (including any operating 
limit) or work practice standard in this subpart during startup, 
shutdown, or malfunction, regardless of whether or not such failure is 
permitted by this subpart.
    Distillate oil means fuel oils that contain 0.05 weight percent 
nitrogen or less and comply with the specifications for fuel oil 
numbers 1 and 2, as defined by the American Society for Testing and 
Materials in ASTM D396-78, ``Standard Specifications for Fuel Oils.''
    Dry scrubber means an add-on air pollution control system that 
injects dry alkaline sorbent (dry injection) or sprays an alkaline 
sorbent (spray dryer) to react with and neutralize acid gas in the 
exhaust stream forming a dry powder material.
    Electric utility steam generating unit means a fossil fuel-fired 
combustion unit of more than 25 megawatts that serves a generator that 
produces electricity for sale. A unit that cogenerates steam and 
electricity and supplies more than one-third of its potential electric 
output capacity and more than 25 megawatts electrical output to any 
utility power distribution system for sale is considered an electric 
utility steam generating unit.
    Electrostatic precipitator means an add-on air pollution control 
device used to capture particulate matter by charging the particles 
using an electrostatic field, collecting the particles using a grounded 
collecting surface, and transporting the particles into a hopper.
    Emission limitation means any emission limit or operating limit.
    Fabric filter means an add-on air pollution control device used to 
capture particulate matter by filtering gas streams through filter 
media, also known as a baghouse.
    Federally enforceable means all limitations and conditions that are 
enforceable by the Administrator, including the requirements of 40 CFR 
parts 60 and 61, requirements within any applicable State 
implementation plan, and any permit requirements established under 40 
CFR 52.21 or 51.18 and 51.24.
    Firetube boiler means a boiler in which hot gases of combustion 
pass through the tubes and water contacts the outside surfaces of the 
tubes.
    Fossil fuel means natural gas, petroleum, coal, and any form of 
solid, liquid, or gaseous fuel derived from such materials.
    Gaseous fuel includes, but is not limited to, natural gas, process 
gas, refinery gas and biogas.
    Heat input means heat derived from combustion of fuel in a boiler 
or process heater and does not include the heat input from preheated 
combustion air, recirculated flue gases, or exhaust gases from other 
sources such as gas turbines, internal combustion engines, kilns, etc.
    Hot water heater means a closed vessel in which water is heated by 
combustion of gaseous fuel and is withdrawn for use external to the 
vessel at pressures not exceeding 160 pounds per square inch gauge 
(psig), including the apparatus by which the heat is generated and all 
controls and devices necessary to prevent water temperatures from 
exceeding 210[deg]F (99[deg]C).
    Industrial boiler means a boiler used in manufacturing, processing, 
mining, and refining or any other industry to provide steam, hot water, 
and/or electricity.
    Large gaseous fuel subcategory means any boiler or process heater 
that burns only gaseous fuels not combined with any liquid or solid 
fuels, has a rated capacity of greater than 10 MMBtu per hour heat 
input, and has an annual capacity factor of greater than 10 percent.
    Large liquid fuel subcategory means any boiler or process heater 
that does not burn any solid fuel and burns any liquid fuel either 
alone or in combination with gaseous fuels, has a rated capacity of 
greater than 10 MMBtu per hour heat input, and has an annual capacity 
factor of greater than 10 percent.
    Large solid fuel subcategory means any watertube boiler or process 
heater that burns any amount of solid fuel either alone or in 
combination with liquid or gaseous fuels, has a rated capacity of 
greater than 10 MMBtu per hour heat input, and has an annual capacity 
factor of greater than 10 percent.
    Limited use gaseous fuel subcategory includes any boiler or process 
heater that burns only gaseous fuels not combined with any liquid or 
solid fuels, has a rated capacity of greater than 10 MMBtu per hour 
heat input, and has a federally enforceable annual average capacity 
factor of equal to or less than 10 percent.
    Limited use liquid fuel subcategory includes any boiler or process 
heater that does not burn any solid fuel and burns any liquid fuel 
either alone or in combination with gaseous fuels, has a rated capacity 
of greater than 10 MMBtu per hour heat input, and has a federally 
enforceable annual average capacity factor of equal to or less than 10 
percent.
    Limited use solid fuel subcategory includes any boiler or process 
heater that burns any amount of solid fuel either alone or in 
combination with liquid or gaseous fuels, has a rated capacity of 
greater than 10 MMBtu per hour heat input, and has a federally 
enforceable annual average capacity factor of equal to or less than 10 
percent.


[[Page 1714]]


    Liquid fossil fuel means petroleum, distillate oil, residual oil 
and any form of liquid fuel derived from such material.
    Liquid fuel includes, but is not limited to, distillate oil, 
residual oil, waste oil, and process liquids.
    Natural gas means:
    (1) A naturally occurring mixture of hydrocarbon and nonhydrocarbon 
gases found in geologic formations beneath the earth's surface, of 
which the principal constituent is methane; or
    (2) Liquid petroleum gas, as defined by the American Society for 
Testing and Materials in ASTM D1835-82, ``Standard Specification for 
Liquid Petroleum Gases.''
    Opacity means the degree to which emissions reduce the transmission 
of light and obscure the view of an object in the background.
    Particulate matter means any finely divided solid or liquid 
material, other than uncombined water, as measured by the test methods 
specified under this subpart, or an alternative method.
    Process heater means an enclosed device using controlled flame, and 
the unit's primary purpose is to transfer heat indirectly to a process 
stream (liquid, gas, or solid) or to a heat transfer material for use 
in a process unit instead of generating steam. Process heaters are 
devices in which the combustion gases do not directly come into contact 
with process materials.
    Residual oil means crude oil, fuel oil numbers 1 and 2 that have a 
nitrogen content greater than 0.05 weight percent, and all fuel oil 
numbers 4, 5 and 6, as defined by the American Society for Testing and 
Materials in ASTM D396-78, ``Standard Specifications for Fuel Oils.''
    Responsible official means responsible official as defined in Sec.  
70.2.
    Small gaseous fuel subcategory includes any boiler or process 
heater that burns only gaseous fuels not combined with any liquid or 
solid fuels, and has a rated capacity of less than or equal to 10 MMBtu 
per hour heat input.
    Small liquid fuel subcategory includes any boiler or process heater 
that does not burn any solid fuel, and burns any liquid fuel either 
alone or in combination with gaseous fuels, and has a rated capacity of 
less than or equal to 10 MMBtu per hour heat input.
    Small solid fuel subcategory includes any firetube boiler that 
burns any amount of solid fuel either alone or in combination with 
liquid or gaseous fuels, and any other boiler or process heater that 
burns any amount of solid fuel either alone or in combination with 
liquid or gaseous fuels, and has a rated capacity of less than or equal 
to 10 MMBtu per hour heat input.
    Solid fuel includes, but is not limited to, coal, wood, biomass, 
tires, plastics, and other nonfossil solid materials.
    Total selected metals means the combination of the following 
metallic hazardous air pollutants: arsenic, beryllium, cadmium, 
chromium, lead, manganese, nickel and selenium.
    Waste heat boiler means a device that recovers normally unused 
energy and converts it to usable heat. Waste heat boilers are also 
referred to as heat recovery steam generators.
    Watertube boiler means a boiler in which water passes through the 
tubes and hot gases of combustion pass over the outside surfaces of the 
tubes.
    Wet scrubber means any add-on air pollution control device that 
mixes an aqueous stream or slurry with the exhaust gases from a boiler 
or process heater to control emissions of particulate matter and/or to 
absorb and neutralize acid gases, such as hydrogen chloride.
    Work practice standard means any design, equipment, work practice, 
or operational standard, or combination thereof, that is promulgated 
pursuant to section 112(h) of the Clean Air Act.


Tables to Subpart DDDDD of Part 63


    As stated in Sec.  63.7500, you must comply with the following 
applicable emission limits:


          Table 1 to Subpart DDDDD of Part 63--Emission Limits
------------------------------------------------------------------------
                                           You must meet these emission
               For . . .                           limits . . .
------------------------------------------------------------------------
1. Each new or reconstructed             a. Emissions of particulate
 industrial, commercial, or               matter must not exceed 0.026
 institutional boiler or process heater   lb per MMBtu of heat input; or
 in the large solid fuel subcategory.    b. Emissions of total selected
                                          metals must not exceed 0.0001
                                          lb per MMBtu of heat input.
                                         c. Emissions of hydrogen
                                          chloride must not exceed 0.02
                                          lb per MMBtu of heat input.
                                         d. Emissions of mercury must
                                          not exceed 0.000003 lb per
                                          MMBtu of heat input.
----------------------------------------
2. Each new or reconstructed             a. Emissions of particulate
 industrial, commercial, institutional    matter must not exceed 0.03 lb
 boiler or process heater in the large    per MMBtu of heat input.
 liquid fuel subcategory.                b. emissions of hydrogen
                                          chloride must not exceed
                                          0.0005 lb per MMBtu of heat
                                          input.
----------------------------------------
3. Each new or reconstructed             a. Emissions of particulate
 industrial, commercial, or               matter must not exceed 0.026
 institutional boiler or process heater   lb per MMBtu of heat input; or
 in the limited use solid fuel           b. Emissions of total selected
 subcategory.                             metals must not exceed 0.0001
                                          lb per MMBtu of heat input
                                         c. Emissions of hydrogen
                                          chloride must not exceed 0.02
                                          lb per MMBtu of heat input.
                                         d. Emissions of mercury must
                                          not exceed 0.000003 lb per
                                          MMBtu of heat input.
----------------------------------------
4. Each new or reconstructed             a. Emissions of particulate
 industrial, commercial, or               matter must not exceed 0.03 lb
 institutional boiler or process heater   per MMBtu of heat input.
 in the limited use liquid fuel          b. Emissions of hydrogen
 subcategory.                             chloride must not exceed
                                          0.0009 lb per MMBtu of heat
                                          input.
----------------------------------------


[[Page 1715]]




5. Each new or reconstructed             a. Emissions of particulate
 industrial, commercial, or               matter must not exceed 0.026
 institutional boiler or process heater   lb per MMBtu of heat input; or
 in the small solid fuel subcategory.    b. Emissions of total selected
                                          metals must not exceed 0.0001
                                          lb per MMBtu of heat input.
                                         c. Emissions of hydrogen
                                          chloride must not exceed 0.02
                                          lb per MMBtu of heat input.
                                         d. Emissions of mercury must
                                          not exceed 0.000003 lb per
                                          MMBtu of heat input.
----------------------------------------
6. Each new or reconstructed             a. Emissions of particulate
 industrial, commercial, or               matter must not exceed 0.03 lb
 institutional boiler or process heater   per MMBtu of heat input.
 in the small liquid fuel subcategory.   b. emissions of hydrogen
                                          chloride must not exceed
                                          0.0009 lb per MMBtu of heat
                                          input.
----------------------------------------
7. Each existing industrial,             a. Emissions of particulate
 commercial, or institutional boiler or   matter must not exceed 0.07 lb
 process heater in the large solid fuel   per MMBtu of heat input; or
 subcategory..                           b. Emissions of total selected
                                          metals must not exceed 0.001
                                          lb per MMBtu of heat input.
                                         c. Emissions of hydrogen
                                          chloride must not exceed 0.09
                                          lb per MMBtu of heat input.
                                         d. Emissions of mercury must
                                          not exceed 0.000007 lb per
                                          MMBtu of heat input.
----------------------------------------
8. Each existing industrial,             a. Emissions of particulate
 commercial, or institutional boiler or   matter must not exceed 0.21 lb
 process heater in the limited use        per MMBtu of heat input; or
 solid fuel subcategory.                 b. Emissions of total selected
                                          metals must not exceed 0.001
                                          lb per MMBtu of heat input.
------------------------------------------------------------------------


    As stated in Sec.  63.7500, you must comply with the applicable 
operating limits:


 Table 2.A to Subpart DDDDD of Part 63--Operating Limits for Boilers and
     Process Heaters in the Large, Limited Use, or Small Solid Fuel
                              Subcategories
------------------------------------------------------------------------
                                                     You must meet these
          For . . .            That is controlled   operating limits . .
                                   with . . .                 .
------------------------------------------------------------------------
1. Each new or reconstructed  a. An add-on contol   i. Maintain opacity
 industrial, commercial, or    other than a wet      to less than or
 institutional boiler or       scrubber or a dry     equal to the
 process heater in the large   scrubber              operating level
 solid fuel subcategory, the                         established during
 limited use solid fuel                              the performance
 subcategory, or the small                           test according to
 solid fuel subcategory.                             the provisions in
                                                     Sec.   63.7530(c)
                                                     that demonstrated
                                                     compliance with the
                                                     emission limits for
                                                     particulate matter
                                                     and mercury or the
                                                     opacity level
                                                     established during
                                                     the performance
                                                     test according to
                                                     the provisions in
                                                     Sec.   63.7530(c)
                                                     that demonstrated
                                                     compliance with the
                                                     alternative
                                                     emission limitation
                                                     for total selected
                                                     metals and the
                                                     mercury emission
                                                     limit; and
                                                    ii. Maintain the
                                                     fuel chlorine
                                                     content to less
                                                     than or equal to
                                                     the operating level
                                                     established during
                                                     the performance
                                                     test according to
                                                     the provisions in
                                                     Sec.   63.7530(c)
                                                     that demonstrated
                                                     compliance with the
                                                     emission limit for
                                                     hydrogen chloride.
                              b. A fabric filter    i. Maintain the
                               either alone or in    fabric filter
                               combination with an   operation such that
                               add-on control        the operating limit
                               other than a wet      established for
                               scrubber or a dry     fabric filters in
                               scrubber.             Sec.
                                                     63.7530(c)(6)(v) is
                                                     maintained; and
                                                    ii. Maintain the
                                                     fuel chlorine
                                                     content to less
                                                     than or equal to
                                                     the operating level
                                                     established during
                                                     the performance
                                                     test according to
                                                     the provisions in
                                                     Sec.   63.7530(c)
                                                     that demonstrated
                                                     compliance with the
                                                     emission limit for
                                                     hydrogen chloride.


[[Page 1716]]




                              c. A wet scrubber...  Maintain the minimum
                                                     pH, pressure drop,
                                                     and liquid flow-
                                                     rate at or above
                                                     the operating
                                                     levels established
                                                     during the
                                                     performance test
                                                     according to
                                                     provisions in Sec.
                                                      63.7530(c) that
                                                     demonstrated
                                                     compliance with the
                                                     emission limits for
                                                     particulate matter,
                                                     mercury, and
                                                     hydrogen chloride
                                                     or the levels
                                                     established during
                                                     the performance
                                                     test according to
                                                     the provisions in
                                                     Sec.   63.7530(c)
                                                     that demonstrated
                                                     compliance with the
                                                     emission limits for
                                                     hydrogen chloride,
                                                     mercury, and the
                                                     alternative total
                                                     selected metals
                                                     emission limit.
                              d. A wet scrubber in  i. Maintain the
                               combination with a    minimum pH,
                               fabric filter.        pressure drop, and
                                                     liquid flow-rate of
                                                     the wet scrubber at
                                                     or above the
                                                     operating levels
                                                     established during
                                                     the performance
                                                     test according to
                                                     provisions in Sec.
                                                      63.7530(c) that
                                                     demonstrated
                                                     compliance with the
                                                     emission limits for
                                                     particulate matter,
                                                     hydrogen chloride,
                                                     and mercury or the
                                                     levels established
                                                     during the
                                                     performance test
                                                     according to the
                                                     provisions in Sec.
                                                      63.7530(c) that
                                                     demonstrated
                                                     compliance with the
                                                     emission limits for
                                                     hydrogen chloride,
                                                     mercury, and the
                                                     alternative total
                                                     selected metals
                                                     emission limit; and
                                                    ii. Maintain the
                                                     fabric filter
                                                     operation such that
                                                     the operating limit
                                                     established for
                                                     fabric filters in
                                                     Sec.
                                                     63.7530(c)(6)(v) is
                                                     maintained.
                              e. A wet scrubber in  Maintain the minimum
                               combination with an   pH, pressure drop,
                               electrostatic         and liquid flow-
                               precipitator.         rate of the wet
                                                     scrubber and the
                                                     minimum voltage and
                                                     secondary current
                                                     or total power
                                                     input of the
                                                     electrostatic
                                                     precipitator at or
                                                     above the operating
                                                     levels established
                                                     during the
                                                     performance test
                                                     according to the
                                                     provisions in Sec.
                                                      63.7530(c) that
                                                     demonstrated
                                                     compliance with the
                                                     emission limits for
                                                     particulate matter,
                                                     hydrogen chloride,
                                                     and mercury or the
                                                     levels established
                                                     during the
                                                     performance test
                                                     according to the
                                                     provisions in Sec.
                                                      63.7530(c) that
                                                     demonstrated
                                                     compliance with the
                                                     emission limits for
                                                     hydrogen chloride,
                                                     mercury, and the
                                                     alternative total
                                                     selected metals
                                                     emission limit.
                              f. A dry scrubber...  i. Maintain the
                                                     minimum sorbent
                                                     injection rate of
                                                     the dry scrubber at
                                                     or above the
                                                     operating levels
                                                     established during
                                                     the performance
                                                     test according to
                                                     the provisions in
                                                     Sec.   63.7530(c)
                                                     that demonstrated
                                                     compliance with the
                                                     emission limit for
                                                     hydrogen chloride
                                                     emissions; and
                                                    ii. Maintain opacity
                                                     to less than or
                                                     equal to the
                                                     operating level
                                                     established during
                                                     the performance
                                                     test according to
                                                     the provisions in
                                                     Sec.   63.7530(c)
                                                     that demonstrated
                                                     compliance with the
                                                     emission limits for
                                                     particulate matter
                                                     and mercury
                                                     emissions or the
                                                     opacity level
                                                     established during
                                                     the performance
                                                     test according to
                                                     the provisions in
                                                     Sec.   63.7530(c)
                                                     that demonstrated
                                                     compliance with the
                                                     alternative
                                                     emission limits for
                                                     total selected
                                                     metals and the
                                                     mercury emission
                                                     limit.


[[Page 1717]]




                              g. A dry scrubber in  i. Maintain minimum
                               combination with a    sorbent injection
                               fabric filter.        rate of the dry
                                                     scrubber at or
                                                     above the operating
                                                     level established
                                                     during the
                                                     performance test
                                                     according to the
                                                     provisions in Sec.
                                                      63.7530(c) that
                                                     demonstrated
                                                     compliance with the
                                                     emission limit for
                                                     hydrogen chloride
                                                     emissions; and
                                                    ii. Maintain the
                                                     fabric filter
                                                     operation such that
                                                     the operating limit
                                                     established for
                                                     fabric filters in
                                                     Sec.
                                                     63.7530(c)(6)(v) is
                                                     maintained.
-----------------------------
2. Each new or reconstructed  a. Either no add-on   i. Maintain the fuel
 industrial, commercial, or    controls or add-on    total selected
 institutional boiler or       controls for which    metals content to
 process heater in the large   you do not wish to    less than or equal
 solid fuel subcategory, the   take credit for any   to the operating
 limited use solid fuel        emission reduction    level established
 subcategory, or the small     of total selected     during the
 solid fuel subcategory that   metals or mercury.    performance test
 is complying with the                               according to the
 alternative total selected                          provisions in Sec.
 metals emission limit                                63.7530(c) that
 instead of the particulate                          demonstrated
 matter emission limit (this                         compliance with the
 is an option for those                              emission limit for
 units that can demonstrate                          total selected
 compliance on the basis of                          metals; and
 fuel analysis without                              ii. Maintain the
 controls).                                          fuel chlorine
                                                     content to less
                                                     than or equal to
                                                     the operating level
                                                     established during
                                                     the performance
                                                     test according to
                                                     the provisions in
                                                     Sec.   63.7530(c)
                                                     that demonstrated
                                                     compliance with the
                                                     emission limit for
                                                     hydrogen chloride;
                                                     and
                                                    iii. Maintain the
                                                     fuel mercury
                                                     content to less
                                                     than or equal to
                                                     the operating level
                                                     established during
                                                     the performance
                                                     test according to
                                                     the provisions in
                                                     Sec.   63.7530(c)
                                                     that demonstrated
                                                     compliance with the
                                                     emission limit for
                                                     mercury.
-----------------------------
3. Each existing industrial,  a. An add-on control  i. Maintain opacity
 commercial, or                other than a wet      to less than or
 institutional boiler or       scrubber or a dry     equal to the
 process heater in the large   scrubber.             operating level
 solid fuel subcategory.                             established during
                                                     the performance
                                                     test according to
                                                     the provisions in
                                                     Sec.   63.7530(c)
                                                     that demonstrated
                                                     compliance with the
                                                     emission limits for
                                                     particulate matter
                                                     and mercury or the
                                                     opacity level
                                                     established during
                                                     the performance
                                                     test according to
                                                     the provisions in
                                                     Sec.   63.7530(c)
                                                     that demonstrated
                                                     compliance with the
                                                     alternative
                                                     emission limit for
                                                     total selected
                                                     metals and the
                                                     mercury emission
                                                     limit; and
                                                    ii. Maintain the
                                                     fuel chlorine
                                                     content to less
                                                     than or equal to
                                                     the operating level
                                                     established during
                                                     the performance
                                                     test according to
                                                     the provisions in
                                                     Sec.   63.7530(c)
                                                     that demonstrated
                                                     compliance with the
                                                     emission limit for
                                                     hydrogen chloride.
                              b. A fabric filter    i. Maintain the
                               either alone or in    fabric filter
                               combination with an   operation such that
                               add-on control        the operating limit
                               other than a wet      established for
                               scrubber or a dry     fabric filters in
                               scrubber.             Sec.
                                                     63.7530(c)(6)(v) is
                                                     maintained; and
                                                    ii. Maintain the
                                                     fuel chlorine
                                                     content to less
                                                     than or equal to
                                                     the operating level
                                                     established during
                                                     the performance
                                                     test according to
                                                     the provisions in
                                                     Sec.   63.7530(c)
                                                     that demonstrated
                                                     compliance with the
                                                     emission limit for
                                                     hydrogen chloride.
                              c. A wet scrubber...  Maintain the minimum
                                                     pH, pressure drop,
                                                     and liquid flow-
                                                     rate at or above
                                                     the operating
                                                     levels established
                                                     during the
                                                     performance test
                                                     according to
                                                     provisions in Sec.
                                                      63.7530(c) that
                                                     demonstrated
                                                     compliance with the
                                                     emission limits for
                                                     particulate matter,
                                                     hydrogen chloride,
                                                     and mercury
                                                     emissions or the
                                                     levels established
                                                     during the
                                                     performance test
                                                     according to the
                                                     provisions in Sec.
                                                      63.7530(c) that
                                                     demonstrated
                                                     compliance with the
                                                     emission limits for
                                                     hydrogen chloride,
                                                     mercury, and the
                                                     alternative total
                                                     selected metals
                                                     emission limit.


[[Page 1718]]




                              d. A wet scrubber in  i. Maintain the
                               combination with a    minimum pH,
                               fabric filter.        pressure drop, and
                                                     liquid flow-rate of
                                                     the wet scrubber at
                                                     or above the
                                                     operating levels
                                                     established during
                                                     the performance
                                                     test according to
                                                     provisions in Sec.
                                                      63.7530(c) that
                                                     demonstrated
                                                     compliance with the
                                                     emission limits for
                                                     particulate matter,
                                                     hydrogen chloride,
                                                     and mercury
                                                     emissions or the
                                                     levels established
                                                     during the
                                                     performance test
                                                     according to the
                                                     provisions in Sec.
                                                      63.7530(c) that
                                                     demonstrated
                                                     compliance with the
                                                     emission limits for
                                                     hydrogen chloride,
                                                     mercury, and the
                                                     alternative total
                                                     selected metals
                                                     emission limit; and
                                                    ii. Maintain the
                                                     fabric filter
                                                     operation such that
                                                     the operating limit
                                                     established for
                                                     fabric filters in
                                                     Sec.
                                                     63.7530(c)(6)(v) is
                                                     maintained.
                              e. A wet scrubber in  Maintain the minimum
                               combination with an   pH, pressure drop,
                               electrostatic         and liquid flow-
                               precipitator.         rate of the wet
                                                     scrubber and the
                                                     minimum voltage and
                                                     secondary current
                                                     or total power
                                                     input of the
                                                     electrostatic
                                                     precipitator at or
                                                     above the operating
                                                     levels established
                                                     during the
                                                     performance test
                                                     according to the
                                                     provisions in Sec.
                                                      63.7530(c) that
                                                     demonstrated
                                                     compliance with the
                                                     emission limits for
                                                     particulate matter,
                                                     hydrogen chloride,
                                                     and mercury
                                                     emissions or the
                                                     levels established
                                                     during the
                                                     performance test
                                                     according to the
                                                     provisions in Sec.
                                                      63.7530(c) that
                                                     demonstrated
                                                     compliance with the
                                                     emission limits for
                                                     hydrogen chloride,
                                                     mercury, and the
                                                     alternative total
                                                     selected metals
                                                     emission limit.
                              f. A dry scrubber...  i. Maintain the
                                                     minimum sorbent
                                                     injection rate of
                                                     the dry scrubber at
                                                     or above the
                                                     operating levels
                                                     established during
                                                     the performance
                                                     test according to
                                                     the provisions in
                                                     Sec.   63.7530(c)
                                                     that demonstrated
                                                     compliance with the
                                                     emission limit for
                                                     hydrogen chloride
                                                     emissions; and
                                                    ii. Maintain opacity
                                                     to less than or
                                                     equal to the
                                                     operating level
                                                     established during
                                                     the performance
                                                     test according to
                                                     the provisions in
                                                     Sec.   63.7530(c)
                                                     that demonstrated
                                                     compliance with the
                                                     emission limits for
                                                     particulate matter
                                                     and mercury or the
                                                     opacity level
                                                     established during
                                                     the performance
                                                     test according to
                                                     the provisions in
                                                     Sec.   63.7530(c)
                                                     that demonstrated
                                                     compliance with the
                                                     alternative
                                                     emission limit for
                                                     total selected
                                                     metals and the
                                                     mercury emission
                                                     limit.
                              g. A dry scrubber in  i. Maintain minimum
                               combination with a    sorbent injection
                               fabric filter.        rate of the dry
                                                     scrubber at or
                                                     above the operating
                                                     level established
                                                     during the
                                                     performance test
                                                     according to the
                                                     provisions in Sec.
                                                      63.7530(c) that
                                                     demonstrated
                                                     compliance with the
                                                     emission limit for
                                                     hydrogen chloride
                                                     emissions; and
                                                    ii. Maintain the
                                                     fabric filter
                                                     operation such that
                                                     the operating limit
                                                     established for
                                                     fabric filters in
                                                     Sec.
                                                     63.7530(c)(6)(v) is
                                                     maintained.
-----------------------------


[[Page 1719]]




4. Each existing industrial,  a. Either no add-on   i. Maintain the fuel
 commercial, or                controls or add-on    total selected
 institutional boiler or       controls for which    metals content to
 process heater in the large   you do not wish to    less than or equal
 solid fuel subcategory that   take credit for any   to the operating
 is complying with the         emission reduction    level established
 alternative total selected    of total selected     during the
 metals emission limit         metals or mercury.    performance test
 instead of the particulate                          according to the
 matter emission limit (this                         provisions in Sec.
 is an option for those                               63.7530(c) that
 units that can demonstrate                          demonstrated
 compliance on the basis of                          compliance with the
 fuel analysis without                               emission limit for
 controls).                                          total selected
                                                     metals; and
                                                    ii. Maintain the
                                                     fuel chlorine
                                                     content to less
                                                     than or equal to
                                                     the operating level
                                                     established during
                                                     the performance
                                                     test according to
                                                     the provisions in
                                                     Sec.   63.7530(c)
                                                     that demonstrated
                                                     compliance with the
                                                     emission limit for
                                                     hydrogen chloride;
                                                     and
                                                    iii. Maintain the
                                                     fuel mercury
                                                     content to less
                                                     than or equal to
                                                     the operating level
                                                     established during
                                                     the performance
                                                     test according to
                                                     the provisions in
                                                     Sec.   63.7530(c)
                                                     that demonstrated
                                                     compliance with the
                                                     emission limit for
                                                     mercury.
-----------------------------
5. Each existing industrial,  a. An add-on control  Maintain opacity to
 commercial, or                other than a wet      less than or equal
 institutional boiler or       scrubber.             to the operating
 process heater in the                               level established
 limited use solid fuel                              during the
 subcategory.                                        performance test
                                                     according to the
                                                     provisions in Sec.
                                                      63.7530(c) that
                                                     demonstrated
                                                     compliance with the
                                                     emission limit for
                                                     particulate matter
                                                     or the operating
                                                     level established
                                                     during the
                                                     performance test
                                                     that demonstrated
                                                     compliance with the
                                                     alternative
                                                     emission limit for
                                                     total selected
                                                     metals.
                              b. A fabric filter    i. Maintain opacity
                               either alone or in    to less than or
                               combination with an   equal to the
                               add-on control        operating level
                               other than a wet      established during
                               scrubber.             the performance
                                                     test according to
                                                     the provisions in
                                                     Sec.   63.7530(c)
                                                     that demonstrated
                                                     compliance with the
                                                     emission limit for
                                                     particulate matter
                                                     or the operating
                                                     level established
                                                     during the
                                                     performance test
                                                     that demonstrated
                                                     compliance with the
                                                     alternative
                                                     emission limit for
                                                     total selected
                                                     metals; and
                                                    ii. Maintain the
                                                     fabric filter
                                                     operation such that
                                                     the operating limit
                                                     established for
                                                     fabric filters in
                                                     Sec.
                                                     63.7530(c)(6)(v) is
                                                     maintained.
                              c. A wet scrubber...  Maintain the minimum
                                                     pressure drop and
                                                     liquid flow-rate at
                                                     or above the
                                                     operating levels
                                                     established during
                                                     the performance
                                                     test according to
                                                     the provisions in
                                                     Sec.   63.7530(c)
                                                     that demonstrated
                                                     compliance with the
                                                     emission limit for
                                                     particulate matter
                                                     emissions or the
                                                     levels established
                                                     during the
                                                     performance test
                                                     according to the
                                                     provisions in Sec.
                                                      63.7530(c) that
                                                     demonstrated
                                                     compliance with the
                                                     alternative total
                                                     selected metals
                                                     emission limit.
                              d. A wet scrubber in  i. Maintain the
                               combination with a    minimum pressure
                               fabric filter.        drop and liquid
                                                     flow-rate at or
                                                     above the operating
                                                     levels established
                                                     during the
                                                     performance test
                                                     according to the
                                                     provisions in Sec.
                                                      63.7530(c) that
                                                     demonstrated
                                                     compliance with the
                                                     emission limit for
                                                     particulate matter
                                                     emissions or the
                                                     levels established
                                                     during the
                                                     performance test
                                                     according to the
                                                     provisions in Sec.
                                                      63.7530(c) that
                                                     demonstrated
                                                     compliance with the
                                                     alternative total
                                                     selected metals
                                                     emission limit; and
                                                    ii. Maintain the
                                                     fabric filter
                                                     operation such that
                                                     the operating limit
                                                     established for
                                                     fabric filters in
                                                     Sec.
                                                     63.7530(c)(6)(v) is
                                                     maintained.


[[Page 1720]]




                              e. A wet scrubber in  Maintain the minimum
                               combination with an   pressure drop and
                               electrostatic c       liquid flow-rate of
                               precipitator.         the wet scrubber
                                                     and the minimum
                                                     voltage and
                                                     secondary current
                                                     of the
                                                     electrostatic
                                                     precipitator at or
                                                     above the operating
                                                     levels established
                                                     during the
                                                     performance test
                                                     according to the
                                                     provisions in Sec.
                                                      63.7530(c) that
                                                     demonstrated
                                                     compliance with the
                                                     emission limit for
                                                     particulate matter
                                                     emissions or the
                                                     levels established
                                                     during the
                                                     performance test
                                                     according to the
                                                     provisions in Sec.
                                                      63.7530(c) that
                                                     demonstrated
                                                     compliance with the
                                                     alternative total
                                                     selected metals
                                                     emission limit.
-----------------------------
6. Each existing industrial,  Either no add-on      Maintain the fuel
 commercial, or                controls for which    total selected
 institutional boiler or       you do not wish to    metals content to
 process heater in the         take credit for any   less than or equal
 limited use solid fuel        emission reduction    to the operating
 subcategory that is           of total selected     level established
 complying with the            metals.               during the
 alternative total selected                          performance test
 metals emission limit                               according to the
 instead of the particulate                          provisions in Sec.
 matter emission limit (this                          63.7530(c) that
 is an option for those                              demonstrated
 units that can demonstrate                          compliance with the
 compliance on the basis of                          emission limit for
 fuel analysis without                               total selected
 controls).                                          metals.
------------------------------------------------------------------------


    As stated in Sec.  63.7500, you must comply with the following 
applicable operating limits:


 Table 2.B to Subpart DDDDD of Part 63--Operating Limits for Boilers and
     Process Heaters in the Large, Limited Use, or Small Liquid Fuel
                              Subcategories
------------------------------------------------------------------------
                                                     You must meet these
          For . . .            That is controlled   operating limits . .
                                   with . . .                 .
------------------------------------------------------------------------
1. Each new or reconstructed  a. An add-on control  i. Maintain opacity
 industrial, commercial,       other than a wet      to less than or
 institutional boiler or       scrubber or a dry     equal to the
 process heater in the large   scrubber.             operating level
 liquid fuel subcategory,                            established during
 the limited use liquid fuel                         the performance
 subcategory, or the small                           test according to
 liquid fuel subcategory                             the provisions in
 (boilers or process heaters                         Sec.   63.7530(c)
 in one of the liquid fuel                           that demonstrated
 subcategories that burn                             compliance with the
 only fossil fuels and gases                         emission limit for
 and do not burn any                                 particulate matter;
 residual oil are excluded                           and
 from this operating limit).                        ii. Maintain the
                                                     fuel chlorine
                                                     content to less
                                                     than or equal to
                                                     the operating level
                                                     established during
                                                     the performance
                                                     test according to
                                                     the provisions in
                                                     Sec.   63.7530(c)
                                                     that demonstrated
                                                     compliance with the
                                                     emission limit for
                                                     hydrogen chloride.
                              b. A fabric filter    i. Maintain the
                               either alone or in    fabric filter
                               combination with an   operation such that
                               add-on control        the operating limit
                               other than a wet      established for
                               scrubber or a dry     fabric filters in
                               scrubber.             Sec.
                                                     63.7530(c)(6)(v) is
                                                     maintained; and
                                                    ii. Maintain the
                                                     fuel chlorine
                                                     content to less
                                                     than or equal to
                                                     the operating level
                                                     established during
                                                     the performance
                                                     test according to
                                                     the provisions in
                                                     Sec.   63.7530(c)
                                                     that demonstrated
                                                     compliance with the
                                                     emission limit for
                                                     hydrogen chloride.
                              c. A wet scrubber...  Maintain the minimum
                                                     pH, pressure drop,
                                                     and liquid flow-
                                                     rate at or above
                                                     the operating
                                                     levels established
                                                     during the
                                                     performance test
                                                     according to
                                                     provisions in Sec.
                                                      63.7530(c) that
                                                     demonstrated
                                                     compliance with the
                                                     emission limits for
                                                     particulate matter
                                                     emissions and
                                                     hydrogen chloride
                                                     emissions.
                              d. A wet scrubber in  i. Maintain the
                               combination with a    minimum pH,
                               fabric filter.        pressure drop, and
                                                     liquid flow-rate of
                                                     the wet scrubber at
                                                     or above the
                                                     operating levels
                                                     established during
                                                     the performance
                                                     test according to
                                                     provisions in Sec.
                                                      63.7530(c) that
                                                     demonstrated
                                                     compliance with the
                                                     emission limits for
                                                     particulate matter
                                                     emissions and
                                                     hydrogen chloride
                                                     emissions; and
                                                    ii. Maintain the
                                                     fabric filter
                                                     operation such that
                                                     the operating limit
                                                     established for
                                                     fabric filters in
                                                     Sec.
                                                     63.7530(c)(6)(v) is
                                                     maintained.


[[Page 1721]]




                              e. A wet scrubber in  Maintain the minimum
                               combination with an   pH, pressure drop,
                               electrostatic         and liquid flow-
                               precipitator.         rate of the wet
                                                     scrubber and the
                                                     minimum voltage and
                                                     secondary current
                                                     or total power
                                                     input of the
                                                     electrostatic
                                                     precipitator at or
                                                     above the operating
                                                     levels established
                                                     during the
                                                     performance test
                                                     according to the
                                                     provisions in Sec.
                                                      63.7530(c) that
                                                     demonstrated
                                                     compliance with the
                                                     emission limits for
                                                     particulate matter
                                                     emissions and
                                                     hydrogen chloride
                                                     emissions.
                              f. A dry scrubber...  i. Maintain the
                                                     minimum sorbent
                                                     injection rate of
                                                     the dry scrubber at
                                                     or above the
                                                     operating level
                                                     established during
                                                     the performance
                                                     test according to
                                                     the provisions in
                                                     Sec.   63.7530(c)
                                                     that demonstrated
                                                     compliance with the
                                                     emission limits for
                                                     hydrogen chloride
                                                     emissions; and
                                                    ii. maintain opacity
                                                     to less than or
                                                     equal to the
                                                     operating level
                                                     established during
                                                     the performance
                                                     test according to
                                                     the provisions in
                                                     Sec.   63.7530(c)
                                                     that demonstrated
                                                     compliance with the
                                                     emission limit for
                                                     particulate matter
                                                     emissions.
                              g. A dry scrubber in  i. Maintain the
                               combination with a    minimum sorbent
                               fabric filter.        injection rate of
                                                     the dry scrubber at
                                                     or above the
                                                     operating level
                                                     established during
                                                     the performance
                                                     test according to
                                                     the provisions in
                                                     Sec.   63.7530(c)
                                                     that demonstrated
                                                     compliance with the
                                                     emission limit for
                                                     hydrogen chloride
                                                     emissions; and
                                                    ii. Maintain the
                                                     fabric filter
                                                     operation such that
                                                     the operating limit
                                                     established for
                                                     fabric filters in
                                                     Sec.
                                                     63.7530(c)(6)(v) is
                                                     maintained.
------------------------------------------------------------------------


    As stated in Sec.  63.7500, you must comply with the following 
applicable work practice standards:


      Table 3 to Subpart DDDDD of Part 63--Work Practice Standards
------------------------------------------------------------------------
             For each . . .                       You must . . .
------------------------------------------------------------------------
1. New or reconstructed industrial,      Continuously monitor carbon
 commercial, or institutional boiler or   monoxide emissions according
 process heater in the large solid fuel   to the procedures in Sec.
 subcategory, the large liquid fuel       63.7525(a) to maintain carbon
 subcategory, or the large gaseous fuel   monoxide emissions at or below
 subcategory.                             an exhaust concentration of
                                          400 ppm by volume on a dry
                                          basis corrected to 3 percent
                                          oxygen. The averaging time
                                          shall be 1 calendar day.
----------------------------------------
2. New or reconstructed industrial,      Continuously monitor carbon
 commercial, or institutional boiler or   monoxide emissions according
 process heater in the limited use        to the procedures in Sec.
 solid fuel subcategory, the limited      63.7525(a) to maintain carbon
 use liquid fuel subcategory, or the      monoxide emissions at or below
 limited use gaseous fuel subcategory.    an exhaust concentration of
                                          400 ppm by volume on a dry
                                          basis corrected to 3 percent
                                          oxygen. The averaging time
                                          shall be 1 calendar day.
------------------------------------------------------------------------


    As stated in Sec.  63.7520, you must comply with the following 
requirements for performance test for existing, new or reconstructed 
affected sources:


  Table 4.A to Subpart DDDDD of Part 63--Requirements for Performance Tests for Particulate Matter Emissions or
   Total Selected Metals Emissions From Boilers or Process Heaters in Large, Limited Use, or Small Solid Fuel
                                                  Subcategories
----------------------------------------------------------------------------------------------------------------
                                                                                               According to the
            For . . .             That is controlled    You must . . .        Using . . .          following
                                      with . . .                                              requirements . . .
----------------------------------------------------------------------------------------------------------------
 1. Each new reconstructed, or    a. Any type of      1. Select sampling  Method 1 of 40 CFR
 existing industrial,              device.             ports location      part 60, appendix
 commercial, or institutional                          and the number of   A.
 boiler or process heater in the                       traverse points.
 large solid fuel subcategory,
 the limited use solid fuel
 subcategory, or the small solid
 fuel subcategory.


[[Page 1722]]




                                                      ii. Determine       Either Method 2 in
                                                       velocity and        appendix A to
                                                       volumetric flow-    part 60 of this
                                                       rate of the stack   chapter, Method
                                                       gas.                2F in appendix A
                                                                           to part 60 of
                                                                           this chapter, or
                                                                           Method 2G of
                                                                           appendix A to
                                                                           part 60 of this
                                                                           chapter..
                                                      iii. Determine      Method 3A or 3B in
                                                       oxygen and carbon   appendix A to
                                                       dioxide             part 60 of this
                                                       concentrations of   chapter.
                                                       the stack gas.
                                                      iv. Measure         Method 4 in
                                                       moisture content    appendix A to
                                                       of the stack gas.   part 60 of this
                                                                           chapter.
                                  b. Any type of      Measure the         Method 5 in
                                   device except       particulate         appendix A to
                                   positive pressure   matter emission     part 60 of this
                                   fabric filters.     concentrations.     chapter or Method
                                                                           17 in appendix A
                                                                           to part 60 of
                                                                           this chapter.
                                  c. Positive         Measure the         Method 5D in
                                   pressure fabric     particulate         appendix A to
                                   filters.            matter emission     part 60 of this
                                                       concentrations.     chapter
                                  d. Any type of      Convert emissions   The F-factor
                                   device.             concentrations to   methodology in
                                                       lb per MMBtu        Method 19 in
                                                       emission rates.     appendix A to
                                                                           part 60 of this
                                                                           chapter.
---------------------------------
 2. Each new reconstructed, or    Any type of device  Measure the total   Method 29 in
 existing industrial,                                  selected metals     appendix A to
 commercial, or institutional                          emissions           part 60 of this
 boiler or process heater in the                       concentrations.     chapter.
 large solid fuel subcategory,
 limited use solid fuel
 subcategory, or the small solid
 fuel subcategory that is
 complying with the alternative
 total selected metals emission
 limit instead of particulate
 matter.
---------------------------------
 3. Each new or reconstructed     a. Either no add-   i. Establish a      (1) Data from the   (a) You must
 industrial, commercial, or        on controls or an   site-specific       continuous          collect opacity
 institutional boiler or process   add-on control      maximum opacity     opacity             monitoring data
 heater in the large solid fuel    other than a wet    level according     monitoring system   every 10 seconds
 subcategory, the limited use      scrubber.           to provisions in    and the PM or       during the entire
 solid fuel subcategory, or the                        Sec.   63.7530(c).  total selected      period of the
 small solid fuel subcategory.                                             metals              three-run PM or
                                                                           performance test.   total selected
                                                                                               metals
                                                                                               performance test;
                                                                                               and
                                                                                              (b) Determine the
                                                                                               maximum opacity
                                                                                               level of all the
                                                                                               1-hour averages
                                                                                               taken during the
                                                                                               three-run
                                                                                               performance test.
                                  b. A wet scrubber.  i. Establish a      (1) Data from the   (a) You must
                                                       site-specific       pressure drop and   collect pressure
                                                       minimum pressure    liquid flow-rate    drop and liquid
                                                       drop and minimum    monitors and the    flow-rate data
                                                       liquid flow-rate    PM or total         every 15 minutes
                                                       operating limit     selected metals     during the entire
                                                       for the wet         performance test.   period of the
                                                       scrubber                                three-run PM or
                                                       according to the                        total selected
                                                       provisions in                           metals
                                                       Sec.                                    performance test;
                                                       63.7530(c)(3).                          and
                                                                                              (b) determine the
                                                                                               average pressure
                                                                                               drop and liquid
                                                                                               flow-rate for
                                                                                               each individual
                                                                                               test run in the
                                                                                               three-run
                                                                                               performance test
                                                                                               by computing the
                                                                                               average of all
                                                                                               the 15-minute
                                                                                               readings taken
                                                                                               during the test
                                                                                               run.
                                  c. A wet scrubber   i. Establish a      (1) Data from the   (a) You must
                                   in combination      site-specific       pressure drop and   collect pressure
                                   with a fabric       minimum pressure    liquid flow-rate    drop and liquid
                                   filter.             drop and liquid     monitors and the    flow-rate data
                                                       flow-rate           PM or total         for the wet
                                                       operating limit     selected metals     scrubber every 15
                                                       for the wet         performance test.   minutes during
                                                       scrubber                                the entire period
                                                       according to the                        of the three-run
                                                       provisions in                           PM or total
                                                       Sec.                                    selected metals
                                                       63.7530(c)(3).                          performance test;
                                                                                               and
                                                                                              (b) Determine the
                                                                                               average pressure
                                                                                               drop and liquid
                                                                                               flow-rate for
                                                                                               each individual
                                                                                               test run in the
                                                                                               three-run
                                                                                               performance test
                                                                                               by computing the
                                                                                               average of all
                                                                                               the 15-minute
                                                                                               readings taken
                                                                                               during the test
                                                                                               run.


[[Page 1723]]




                                  d. A wet scrubber   i. Establish a      (1) Data from the   (a) You must
                                   in combination      site-specific       pressure drop and   collect pressure
                                   with an             minimum pressure    liquid flow-rate    drop and liquid
                                   electrostatic       drop and liquid     monitors for the    flow-rate data
                                   precipitator.       flow-rate for the   wet scrubber and    for the wet
                                                       wet scrubber and    from total          scrubber and
                                                       minimum voltage     current and         secondary current
                                                       and secondary       voltage monitors    and voltage or
                                                       current or total    for the             total power input
                                                       power input of      electrostatic       for the
                                                       the electrostatic   precipitator or     electrostatic
                                                       precipitator        and the PM or       precipitator
                                                       according to the    total selected      every 15 minutes
                                                       provisions in       metals              during the entire
                                                       Sec.                performance test.   period of the
                                                       63.7530(c)(3).                          three-run PM or
                                                                                               total selected
                                                                                               metals
                                                                                               performance test;
                                                                                               and
                                                                                              (b) Determine the
                                                                                               average for each
                                                                                               by computing the
                                                                                               average of all 15-
                                                                                               minute readings
                                                                                               taken during the
                                                                                               test run.
---------------------------------
4. Each new or reconstructed      a. Either no add-   i. Establish a      (1) The fuel total  (a) You must
 industrial, commercial,           on controls or an   site-specific       selected metals     collect one
 institutional boiler or process   add-on control      maximum inlet       content analysis    sample of the
 heater in the large solid fuel    for which you do    fuel total          results and the     worst-case fuel
 subcategory, the limited use      not wish to take    selected metals     calculations done   stream entering
 solid fuel subcategory, or the    credit for          content operating   according to the    the boiler or
 small solid fuel subcategory      reductions in       limit according     provisions in       process heater
 that is complying with the        total selected      to the provisions   Sec.   63.7530(c).  for each test run
 alternative total selected        metals.             in Sec.                                 during the three-
 metals emission limit instead                         63.7530(c).                             run performance
 of the particulate matter                                                                     test; and
 emission limit (this is an                                                                   (b) Determine the
 option for those units that can                                                               total selected
 demonstrate compliance on the                                                                 metals content
 basis of fuel analysis without                                                                and heating value
 controls).                                                                                    of the sample
                                                                                               according to your
                                                                                               site-specific
                                                                                               test plan as
                                                                                               required in Sec.
                                                                                                63.7520(a); and
                                                                                              (c) Determine the
                                                                                               maximum total
                                                                                               selected metals
                                                                                               content operating
                                                                                               limit according
                                                                                               to the procedures
                                                                                               in Sec.
                                                                                               63.7530(c).
---------------------------------
5. Each existing industrial,      a. Either no add-   i. Establish a      (1) Data from the   (a) You must
 commercial, or institutional      on controls or an   site-specific       continuous          collect opacity
 boiler or process heater in the   add-on control      maximum opacity     opacity             monitoring data
 large solid fuel subcategory or   other than a wet    level according     monitoring system   every 10 seconds
 the limited use solid fuel        scrubber.           to provisions in    and the PM or       during the entire
 subcategory.                                          Sec.   63.7530(c).  total selected      period of the
                                                                           metals              three-run PM or
                                                                           performance test.   total selected
                                                                                               metals
                                                                                               performance test;
                                                                                               and
                                                                                              (b) Determine the
                                                                                               maximum opacity
                                                                                               level for all the
                                                                                               1-hour averages
                                                                                               taken during the
                                                                                               three-run
                                                                                               performance test.
                                  b. A wet scrubber.  i. Establish a      (1) Data from the   (a) You must
                                                       site-specific       pressure drop and   collect pressure
                                                       minimum pressure    liquid flow-rate    drop and liquid
                                                       drop and minimum    monitors and the    flow-rate data
                                                       liquid flow-rate    PM or total         every 15 minutes
                                                       operating limit     selected metals     during the entire
                                                       for the wet         performance test.   period of the
                                                       scrubber                                three-run PM or
                                                       according to the                        total selected
                                                       provisions in                           metals
                                                       Sec.                                    performance test;
                                                       63.7530(c)(3).                          and
                                                                                              (b) Determine the
                                                                                               average pressure
                                                                                               drop and liquid
                                                                                               flow-rate for
                                                                                               each individual
                                                                                               test run in the
                                                                                               three-run
                                                                                               performance test
                                                                                               by computing the
                                                                                               average of all
                                                                                               the 15-minute
                                                                                               readings taken
                                                                                               during the test
                                                                                               run.
                                  c. A wet scrubber   i. Establish a      (1) Data from the   (a) You must
                                   in combination      site-specific       pressure drop       collect pressure
                                   with a fabric       minimum pressure    liquid flow-rate    drop and liquid
                                   filter.             drop and liquid     monitors and the    flow-rate data
                                                       flow-rate           PM or total         for the wet
                                                       operating limit     selected metals     scrubber every 15
                                                       for the wet         performance test.   minutes during
                                                       scrubber                                the entire period
                                                       according to the                        of the three-run
                                                       provisions in                           PM or total
                                                       Sec.                                    selected metals
                                                       63.7530(c)(3).                          performance test;
                                                                                               and
                                                                                              (b) Determine the
                                                                                               average pressure
                                                                                               drop and liquid
                                                                                               flow-rate for
                                                                                               each individual
                                                                                               test run in the
                                                                                               three-run
                                                                                               performance test
                                                                                               by computing the
                                                                                               average of all
                                                                                               the 15-minute
                                                                                               readings taken
                                                                                               during the test
                                                                                               run.


[[Page 1724]]




                                  d. A wet scrubber   i. Establish a      (1) Data from the   (a) You must
                                   in combination      site-specific       pressure drop and   collect pressure
                                   with an electro-    minimum pressure    liquid flow-rate    drop and liquid
                                   static              drop and liquid     monitors for the    flow-rate data
                                   precipitator.       flow-rate for the   wet scrubber and    for the wet
                                                       wet scrubber and    from the current    scrubber and
                                                       minimum voltage     and voltage         secondary current
                                                       and secondary       monitors for the    and voltage or
                                                       current or total    electrostatic       total power input
                                                       power input of      precipitator and    for the
                                                       the electrostatic   the PM or total     electrostatic
                                                       precipitator        selected metals     precipitator
                                                       according to the    performance test.   every 15 minutes
                                                       provisions in                           during the entire
                                                       Sec.                                    period of the
                                                       63.7530(c)(3).                          three-run PM or
                                                                                               total selected
                                                                                               metals
                                                                                               performance test;
                                                                                               and
                                                                                              b. Determine the
                                                                                               average for each
                                                                                               by computing the
                                                                                               average of all 15-
                                                                                               minute readings
                                                                                               taken during each
                                                                                               test run.
---------------------------------
6. Each existing industrial,      a. Either no add-   i. Establish a      (1) The fuel total  (a) You must
 commercial or institutional       on controls or an   site-specific       selected metals     collect one
 boiler or process heater in the   add-on control      maximum inlet       content analysis    sample of the
 large solid fuel subcategory or   for which you do    fuel total          results and the     worst-case fuel
 the limited use solid fuel        not wish to take    selected metals     calculations done   stream entering
 subcategory that is complying     credit for          content operating   according to the    the boiler or
 with the alternative total        reductions in       limit according     provisions in       process heater
 selected metals emission limit    total selected      to the provisions   Sec.   63.7530(c).  for each test run
 instead of the particulate        metals.             in Sec.                                 during the three-
 matter emission limit (this is                        63.7530(c).                             run performance
 an option for those units that                                                                test; and
 can demonstrate compliance on                                                                (b) Determine the
 the basis of fuel analysis                                                                    total selected
 without controls).                                                                            metals content
                                                                                               and heating value
                                                                                               of the sample
                                                                                               according to your
                                                                                               site-specific
                                                                                               test plan as
                                                                                               required in Sec.
                                                                                                63.7520(a); and
                                                                                              (c) Determine the
                                                                                               maximum total
                                                                                               selected metals
                                                                                               content operating
                                                                                               limit according
                                                                                               to the procedures