[Code of Federal Regulations]

[Title 40, Volume 28]

[Revised as of July 1, 2006]

From the U.S. Government Printing Office via GPO Access

[CITE: 40CFR403.6]



[Page 15-20]

 

                   TITLE 40--PROTECTION OF ENVIRONMENT

 

         CHAPTER I--ENVIRONMENTAL PROTECTION AGENCY (CONTINUED)

 

PART 403_GENERAL PRETREATMENT REGULATIONS FOR EXISTING AND NEW SOURCES OF 

POLLUTION--Table of Contents

 

Sec.  403.6  National pretreatment standards: Categorical standards.



    National pretreatment standards specifying quantities or 

concentrations of pollutants or pollutant properties which may be 

discharged to a POTW by existing or new industrial users in specific 

industrial subcategories will be established as separate regulations 

under the appropriate subpart of 40 CFR chapter I, subchapter N. These 

standards, unless specifically noted otherwise, shall be in addition to 

all applicable pretreatment standards and requirements set forth in this 

part.

    (a) Category Determination Request--(1) Application Deadline. Within 

60 days after the effective date of a Pretreatment Standard for a 

subcategory under which an Industrial User may be included, the 

Industrial User or POTW may request that the Water Management Division 

Director or Director, as appropriate, provide written certification on 

whether the Industrial User falls within that particular subcategory. If 

an existing Industrial User adds or changes a process or operation which 

may be included in a subcategory, the existing Industrial User must 

request this certification prior to commencing discharge from the added 

or changed processes or operation. A New Source must request this 

certification prior to commencing discharge. Where a request for 

certification is submitted by a POTW, the POTW shall notify any affected 

Industrial User of such submission. The Industrial User may provide 

written comments on the POTW submission to the Water Management Division 

Director or Director, as appropriate, within 30 days of notification.

    (2) Contents of Application. Each request shall contain a statement:

    (i) Describing which subcategories might be applicable; and

    (ii) Citing evidence and reasons why a particular subcategory is 

applicable and why others are not applicable. Any person signing the 

application statement submitted pursuant to this section shall make the 

following certification:



    I certify under penalty of law that this document and all 

attachments were prepared under my direction or supervision in 

accordance with a system designed to assure that qualified personnel 

properly gather and evaluate the information submitted. Based on my 

inquiry of the person or persons who manage the system, or those persons 

directly responsible for gathering the information, the information 

submitted is, to the best of my knowledge and belief, true, accurate, 

and complete. I am aware that there are significant penalties for 

submitting false information, including the possibility of fine and 

imprisonment for knowing violations.



    (3) Deficient requests. The Water Management Division Director or 

Director will only act on written requests for determinations that 

contain all of the information required. Persons who have made 

incomplete submissions will be notified by the Water Management Division 

Director or Director that their requests are deficient and, unless the 

time period is extended, will be given 30 days to correct the 

deficiency. If the deficiency is not corrected within 30 days or within 

an extended period allowed by the Water Management Division Director or 

the Director, the request for a determination shall be denied.

    (4) Final decision. (i) When the Water Management Division Director 

or Director receives a submittal he or she will, after determining that 

it contains all of the information required by paragraph (2) of this 

section, consider the submission, any additional evidence that may have 

been requested, and any other available information relevant to the 

request. The Water Management Division Director or Director will then



[[Page 16]]



make a written determination of the applicable subcategory and state the 

reasons for the determination.

    (ii) Where the request is submitted to the Director, the Director 

shall forward the determination described in this paragraph to the Water 

Management Division Director who may make a final determination. The 

Water Management Division Director may waive receipt of these 

determinations. If the Water Management Division Director does not 

modify the Director's decision within 60 days after receipt thereof, or 

if the Water Management Division Director waives receipt of the 

determination, the Director's decision is final.

    (iii) Where the request is submitted by the Industrial User or POTW 

to the Water Management Division Director or where the Water Management 

Division Director elects to modify the Director's decision, the Water 

Management Division Director's decision will be final.

    (iv) The Water Management Division Director or Director, as 

appropriate, shall send a copy of the determination to the affected 

Industrial User and the POTW. Where the final determination is made by 

the Water Management Division Director, he or she shall send a copy of 

the determination to the Director.

    (5) Requests for hearing and/or legal decision. Within 30 days 

following the date of receipt of notice of the final determination as 

provided for by paragraph (a)(4)(iv) of this section, the Requester may 

submit a petition to reconsider or contest the decision to the Regional 

Administrator who shall act on such petition expeditiously and state the 

reasons for his or her determination in writing.

    (b) Deadline for compliance with categorical standards. Compliance 

by existing sources with categorical Pretreatment Standards shall be 

within 3 years of the date the Standard is effective unless a shorter 

compliance time is specified in the appropriate subpart of 40 CFR 

chapter I, subchapter N. Direct dischargers with NPDES Permits modified 

or reissued to provide a variance pursuant to section 301(i)(2) of the 

Act shall be required to meet compliance dates set in any applicable 

categorical Pretreatment Standard. Existing sources which become 

Industrial Users subsequent to promulgation of an applicable categorical 

Pretreatment Standard shall be considered existing Industrial Users 

except where such sources meet the definition of a New Source as defined 

in Sec.  403.3(m). New Sources shall install and have in operating 

condition, and shall ``start-up'' all pollution control equipment 

required to meet applicable Pretreatment Standards before beginning to 

Discharge. Within the shortest feasible time (not to exceed 90 days), 

New Sources must meet all applicable Pretreatment Standards.

    (c)(1) Concentration and mass limits. Pollutant discharge limits in 

categorical Pretreatment Standards will be expressed either as 

concentration or mass limits. Wherever possible, where concentration 

limits are specified in standards, equivalent mass limits will be 

provided so that local, State or Federal authorities responsible for 

enforcement may use either concentration or mass limits. Limits in 

categorical Pretreatment Standards shall apply to the effluent of the 

process regulated by the Standard, or as otherwise specified by the 

standard.

    (2) When the limits in a categorical Pretreatment Standard are 

expressed only in terms of mass of pollutant per unit of production, the 

Control Authority may convert the limits to equivalent limitations 

expressed either as mass of pollutant discharged per day or effluent 

concentration for purposes of calculating effluent limitations 

applicable to individual Industrial Users.

    (3) A Control Authority calculating equivalent mass-per-day 

limitations under paragraph (c)(2) of this section shall calculate such 

limitations by multiplying the limits in the Standard by the Industrial 

User's average rate of production. This average rate of production shall 

be based not upon the designed production capacity but rather upon a 

reasonable measure of the Industrial User's actual long-term daily 

production, such as the average daily production during a representative 

year. For new sources, actual production shall be estimated using 

projected production.

    (4) A Control Authority calculating equivalent concentration 

limitations



[[Page 17]]



under paragraph (c)(2) of this section shall calculate such limitations 

by dividing the mass limitations derived under paragraph (c)(3) of this 

section by the average daily flow rate of the Industrial User's 

regulated process wastewater. This average daily flow rate shall be 

based upon a reasonable measure of the Industrial User's actual long-

term average flow rate, such as the average daily flow rate during the 

representative year.

    (5) When the limits in a categorical Pretreatment Standard are 

expressed only in terms of pollutant concentrations, an Industrial User 

may request that the Control Authority convert the limits to equivalent 

mass limits. The determination to convert concentration limits to mass 

limits is within the discretion of the Control Authority. The Control 

Authority may establish equivalent mass limits only if the Industrial 

User meets all the following conditions in paragraph (c)(5)(i)(A) 

through (c)(5)(i)(E) of this section.

    (i) To be eligible for equivalent mass limits, the Industrial User 

must:

    (A) Employ, or demonstrate that it will employ, water conservation 

methods and technologies that substantially reduce water use during the 

term of its control mechanism;

    (B) Currently use control and treatment technologies adequate to 

achieve compliance with the applicable categorical Pretreatment 

Standard, and not have used dilution as a substitute for treatment;

    (C) Provide sufficient information to establish the facility's 

actual average daily flow rate for all wastestreams, based on data from 

a continuous effluent flow monitoring device, as well as the facility's 

long-term average production rate. Both the actual average daily flow 

rate and long-term average production rate must be representative of 

current operating conditions;

    (D) Not have daily flow rates, production levels, or pollutant 

levels that vary so significantly that equivalent mass limits are not 

appropriate to control the Discharge; and

    (E) Have consistently complied with all applicable categorical 

Pretreatment Standards during the period prior to the Industrial User's 

request for equivalent mass limits.

    (ii) An Industrial User subject to equivalent mass limits must:

    (A) Maintain and effectively operate control and treatment 

technologies adequate to achieve compliance with the equivalent mass 

limits;

    (B) Continue to record the facility's flow rates through the use of 

a continuous effluent flow monitoring device;

    (C) Continue to record the facility's production rates and notify 

the Control Authority whenever production rates are expected to vary by 

more than 20 percent from its baseline production rates determined in 

paragraph (c)(5)(i)(C) of this section. Upon notification of a revised 

production rate, the Control Authority must reassess the equivalent mass 

limit and revise the limit as necessary to reflect changed conditions at 

the facility; and

    (D) Continue to employ the same or comparable water conservation 

methods and technologies as those implemented pursuant to paragraph 

(c)(5)(i)(A) of this section so long as it discharges under an 

equivalent mass limit.

    (iii) A Control Authority which chooses to establish equivalent mass 

limits:

    (A) Must calculate the equivalent mass limit by multiplying the 

actual average daily flow rate of the regulated process(es) of the 

Industrial User by the concentration-based daily maximum and monthly 

average Standard for the applicable categorical Pretreatment Standard 

and the appropriate unit conversion factor;

    (B) Upon notification of a revised production rate, must reassess 

the equivalent mass limit and recalculate the limit as necessary to 

reflect changed conditions at the facility; and

    (C) May retain the same equivalent mass limit in subsequent control 

mechanism terms if the Industrial User's actual average daily flow rate 

was reduced solely as a result of the implementation of water 

conservation methods and technologies, and the actual average daily flow 

rates used in the original calculation of the equivalent mass limit were 

not based on the use of dilution as a substitute for treatment pursuant 

to paragraph (d) of this section. The Industrial User must also be



[[Page 18]]



in compliance with Sec.  403.17 (regarding the prohibition of bypass).

    (iv) The Control Authority may not express limits in terms of mass 

for pollutants such as pH, temperature, radiation, or other pollutants 

which cannot appropriately be expressed as mass.

    (6) The Control Authority may convert the mass limits of the 

categorical Pretreatment Standards at 40 CFR parts 414, 419, and 455 to 

concentration limits for purposes of calculating limitations applicable 

to individual Industrial Users under the following conditions. When 

converting such limits to concentration limits, the Control Authority 

must use the concentrations listed in the applicable subparts of 40 CFR 

parts 414, 419, and 455 and document that dilution is not being 

substituted for treatment as prohibited by paragraph (d) of this 

section.

    (7) Equivalent limitations calculated in accordance with paragraphs 

(c)(3), (c)(4), (c)(5) and (c)(6) of this section are deemed 

Pretreatment Standards for the purposes of section 307(d) of the Act and 

this part. The Control Authority must document how the equivalent limits 

were derived and make this information publicly available. Once 

incorporated into its control mechanism, the Industrial User must comply 

with the equivalent limitations in lieu of the promulgated categorical 

standards from which the equivalent limitations were derived.

    (8) Many categorical Pretreatment Standards specify one limit for 

calculating maximum daily discharge limitations and a second limit for 

calculating maximum monthly average, or 4-day average, limitations. 

Where such Standards are being applied, the same production or flow 

figure shall be used in calculating both the average and the maximum 

equivalent limitation.

    (9) Any Industrial User operating under a control mechanism 

incorporating equivalent mass or concentration limits calculated from a 

production based standard shall notify the Control Authority within two 

(2) business days after the User has a reasonable basis to know that the 

production level will significantly change within the next calendar 

month. Any User not notifying the Control Authority of such anticipated 

change will be required to meet the mass or concentration limits in its 

control mechanism that were based on the original estimate of the long 

term average production rate.

    (d) Dilution prohibited as substitute for treatment. Except where 

expressly authorized to do so by an applicable Pretreatment Standard or 

Requirement, no Industrial User shall ever increase the use of process 

water, or in any other way attempt to dilute a Discharge as a partial or 

complete substitute for adequate treatment to achieve compliance with a 

Pretreatment Standard or Requirement. The Control Authority may impose 

mass limitations on Industrial Users which are using dilution to meet 

applicable Pretreatment Standards or Requirements, or in other cases 

where the imposition of mass limitations is appropriate.

    (e) Combined wastestream formula. Where process effluent is mixed 

prior to treatment with wastewaters other than those generated by the 

regulated process, fixed alternative discharge limits may be derived by 

the Control Authority or by the Industrial User with the written 

concurrence of the Control Authority. These alternative limits shall be 

applied to the mixed effluent. When deriving alternative categorical 

limits, the Control Authority or Industrial User shall calculate both an 

alternative daily maximum value using the daily maximum value(s) 

specified in the appropriate categorical Pretreatment Standard(s) and an 

alternative consecutive sampling day average value using the monthly 

average value(s) specified in the appropriate categorical Pretreatment 

Standard(s). The Industrial User shall comply with the alternative daily 

maximum and monthly average limits fixed by the Control Authority until 

the Control Authority modifies the limits or approves an Industrial User 

modification request. Modification is authorized whenever there is a 

material or significant change in the values used in the calculation to 

fix alternative limits for the regulated pollutant. An Industrial User 

must immediately report any such material or significant change to



[[Page 19]]



the Control Authority. Where appropriate new alternative categorical 

limits shall be calculated within 30 days.

    (1) Alternative limit calculation. For purposes of these formulas, 

the ``average daily flow'' means a reasonable measure of the average 

daily flow for a 30-day period. For new sources, flows shall be 

estimated using projected values. The alternative limit for a specified 

pollutant will be derived by the use of either of the following 

formulas:

    (i) Alternative concentration limit.

    [GRAPHIC] [TIFF OMITTED] TC15NO91.012

    

where



CT=the alternative concentration limit for the combined 

wastestream.

Ci=the categorical Pretreatment Standard concentration limit 

for a pollutant in the regulated stream i.

Fi=the average daily flow (at least a 30-day average) of 

stream i to the extent that it is regulated for such pollutant.

FD=the average daily flow (at least a 30-day average) from: 

(a) Boiler blowdown streams, non-contact cooling streams, stormwater 

streams, and demineralizer backwash streams; provided, however, that 

where such streams contain a significant amount of a pollutant, and the 

combination of such streams, prior to treatment, with an Industrial 

User's regulated process wastestream(s) will result in a substantial 

reduction of that pollutant, the Control Authority, upon application of 

the Industrial User, may exercise its discretion to determine whether 

such stream(s) should be classified as diluted or unregulated. In its 

application to the Control Authority, the Industrial User must provide 

engineering, production, sampling and analysis and such other 

information so that the Control Authority can make its determination; or 

(b) sanitary wastestreams where such streams are not regulated by a 

Categorical Pretreatment Standard; or (c) from any process wastestreams 

which were or could have been entirely exempted from categorical 

Pretreatment Standards pursuant to paragraph 8 of the NRDC v. Costle 

Consent Decree (12 ERC 1833) for one or more of the following reasons 

(see appendix D of this part):

    (1) The pollutants of concern are not detectable in the effluent 

from the Industrial User (paragraph (8)(a)(iii));

    (2) The pollutants of concern are present only in trace amounts and 

are neither causing nor likely to cause toxic effects (paragraph 

(8)(a)(iii));

    (3) The pollutants of concern are present in amounts too small to be 

effectively reduced by technologies known to the Administrator 

(paragraph (8)(a)(iii)); or

    (4) The wastestream contains only pollutants which are compatible 

with the POTW (paragraph (8)(b)(i)).

FT=The average daily flow (at least a 30-day average) through 

the combined treatment facility (includes Fi, FD 

and unregulated streams).

N=The total number of regulated streams.



    (ii) Alternative mass limit.

    [GRAPHIC] [TIFF OMITTED] TC15NO91.013

    

where



MT=the alternative mass limit for a pollutant in the combined 

wastestream.

Mi=the categorical Pretreatment Standard mass limit for a 

pollutant in the regulated stream i (the categorical pretreatment mass 

limit multiplied by the appropriate measure of production).

Fi=the average flow (at least a 30-day average) of stream i 

to the extent that it is regulated for such pollutant.

FD=the average daily flow (at least a 30-day average) from: 

(a) Boiler blowdown streams, non-contact cooling streams, stormwater 

streams, and demineralizer backwash streams; provided, however, that 

where such streams contain a significant amount of a pollutant, and the 

combination of such streams, prior to treatment, with an Industrial 

User's regulated process wastestream(s) will result in a substantial 

reduction of that pollutant, the Control Authority, upon application of 

the Industrial User, may exercise its discretion to determine whether 

such stream(s) should be classified as diluted or unregulated. In its 

application to the Control Authority, the Industrial User must provide 

engineering, production, sampling and analysis and such other 

information so that the Control Authority can make its determination; or 

(b) sanitary wastestreams where such streams are not regulated by a 

categorical Pretreatment Standard; or (c) from any process wastestreams 

which were or could have been entirely exempted from categorical 

Pretreatment Standards pursuant to paragraph 8 of the NRDC v. Costle 

Consent Decree (12 ERC 1833) for one or more of the



[[Page 20]]



following reasons (see appendix D of this part):

    (1) The pollutants of concern are not detectable in the effluent 

from the Industrial User (paragraph (8)(a)(iii));

    (2) The pollutants of concern are present only in trace amounts and 

are neither causing nor likely to cause toxic effects (paragraph 

(8)(a)(iii));

    (3) The pollutants of concern are present in amounts too small to be 

effectively reduced by technologies known to the Administrator 

(paragraph (8)(a)(iii)); or

    (4) The wastestream contains only pollutants which are compatible 

with the POTW (paragraph (8)(b)(i)).

FT=The average flow (at least a 30-day average) through the 

combined treatment facility (includes Fi, FD and 

unregulated streams).

N=The total number of regulated streams.



    (2) Alternate limits below detection limit. An alternative 

pretreatment limit may not be used if the alternative limit is below the 

analytical detection limit for any of the regulated pollutants.

    (3) Self-monitoring. Self-monitoring required to insure compliance 

with the alternative categorical limit shall be conducted in accordance 

with the requirements of Sec.  403.12(g).

    (4) Choice of monitoring location. Where a treated regulated process 

wastestream is combined prior to treatment with wastewaters other than 

those generated by the regulated process, the Industrial User may 

monitor either the segregated process wastestream or the combined 

wastestream for the purpose of determining compliance with applicable 

Pretreatment Standards. If the Industrial User chooses to monitor the 

segregated process wastestream, it shall apply the applicable 

categorical Pretreatment Standard. If the User chooses to monitor the 

combined wastestream, it shall apply an alternative discharge limit 

calculated using the combined wastestream formula as provided in this 

section. The Industrial User may change monitoring points only after 

receiving approval from the Control Authority. The Control Authority 

shall ensure that any change in an Industrial User's monitoring point(s) 

will not allow the User to substitute dilution for adequate treatment to 

achieve compliance with applicable Standards.



[46 FR 9439, Jan. 28, 1981, as amended at 49 FR 21037, May 17, 1984; 49 

FR 31224, Aug. 3, 1984; 51 FR 20430, June 4, 1986; 51 FR 23760, July 1, 

1986; 53 FR 40610, Oct. 17, 1988; 55 FR 30129, July 24, 1990; 58 FR 

18017, Apr. 7, 1993; 70 FR 60192, Oct. 14, 2005]