[Code of Federal Regulations]
[Title 40, Volume 14]
[Revised as of July 1, 2003]
From the U.S. Government Printing Office via GPO Access
[CITE: 40CFR75.31]
[Page 261-263]
TITLE 40--PROTECTION OF ENVIRONMENT
CHAPTER I--ENVIRONMENTAL PROTECTION AGENCY (CONTINUED)
PART 75--CONTINUOUS EMISSION MONITORING--Table of Contents
Subpart D--Missing Data Substitution Procedures
Sec. 75.31 Initial missing data procedures.
(a) During the first 720 quality-assured monitor operating hours
following initial certification of the required SO2,
CO2, O2 or moisture monitoring system(s) at a
particular unit or stack location (i.e., the date and time at which
quality-assured data begins to be recorded by CEMS(s) installed at that
location), and during the first 2,160 quality-assured monitor operating
hours following initial certification of the required NOX-
diluent, NOX concentration, or flow monitoring system(s) at
the unit or stack location, the owner or operator shall provide
substitute data required under this subpart according to the procedures
in paragraphs (b) and (c) of this section. The owner or operator of a
unit shall use these procedures for no longer than three years (26,280
clock hours) following initial certification.
(b) SO2, CO2, or O2 concentration
data and moisture data. For each hour of missing SO2 or
CO2 pollutant concentration data (including CO2
data
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converted from O2 data using the procedures in appendix F of
this part), or missing O2 or CO2 diluent
concentration data used to calculate heat input, or missing moisture
data, the owner or operator shall calculate the substitute data as
follows:
(1) Whenever prior quality-assured data exist, the owner or operator
shall substitute, by means of the data acquisition and handling system,
for each hour of missing data, the average of the hourly SO2,
CO2 or O2 concentrations or moisture percentages
recorded by a certified monitor for the unit operating hour immediately
before and the unit operating hour immediately after the missing data
period.
(2) Whenever no prior quality-assured SO2, CO2
or O2 concentration data or moisture data exist, the owner or
operator shall substitute, as applicable, for each hour of missing data,
the maximum potential SO2 concentration or the maximum
potential CO2 concentration or the minimum potential
O2 concentration or (unless Equation 19-3, 19-4 or 19-8 in
Method 19 in appendix A to part 60 of this chapter is used to determine
NOX emission rate) the minimum potential moisture percentage,
as specified, respectively, in sections 2.1.1.1, 2.1.3.1, 2.1.3.2 and
2.1.5 of appendix A to this part. If Equation 19-3, 19-4 or 19-8 in
Method 19 in appendix A to part 60 of this chapter is used to determine
NOX emission rate, substitute the maximum potential moisture
percentage, as specified in section 2.1.6 of appendix A to this part.
(c) Volumetric flow and NOX emission rate or NOX
concentration data (load ranges or operational bins used). The
procedures in this paragraph apply to affected units for which load-
based ranges or non-load-based operational bins, as defined,
respectively, in sections 2 and 3 of appendix C to this part are used to
provide substitute NOX and flow rate data. For each hour of
missing volumetric flow rate data, NOX emission rate data, or
NOX concentration data used to determine NOX mass
emissions:
(1) Whenever prior quality-assured data exist in the load range (or
operational bin) corresponding to the operating load (or operating
conditions) at the time of the missing data period, the owner or
operator shall substitute, by means of the automated data acquisition
and handling system, for each hour of missing data, the arithmetic
average of all of the prior quality-assured hourly flow rates,
NOX emission rates, or NOX concentrations in the
corresponding load range (or operational bin) as determined using the
procedure in appendix C to this part. When non-load-based operational
bins are used, if essential operating or parametric data are unavailable
for any hour in the missing data period, such that the operational bin
cannot be determined, the owner or operator shall, for that hour,
substitute (as applicable) the maximum potential flow rate as specified
in section 2.1.4.1 of appendix A to this part or the maximum potential
NOX emission rate or the maximum potential NOX
concentration as specified in section 2.1.2.1 of appendix A to this
part.
(2) This paragraph (c)(2) does not apply to non-load-based units
using operational bins. Whenever no prior quality-assured flow or
NOX emission rate or NOX concentration data exist
for the corresponding load range, the owner or operator shall
substitute, for each hour of missing data, the average hourly flow rate
or the average hourly NOX emission rate or NOX
concentration at the next higher level load range for which quality-
assured data are available.
(3) Whenever no prior quality-assured flow rate or NOX
emission rate or NOX concentration data exist for the
corresponding load range, or any higher load range (or for non-load-
based units using operational bins, when no prior quality-assured data
exist in the corresponding operational bin), the owner or operator
shall, as applicable, substitute, for each hour of missing data, the
maximum potential flow rate as specified in section 2.1.4.1 of appendix
A to this part or shall substitute the maximum potential NOX
emission rate or the maximum potential NOX concentration, as
specified in section 2.1.2.1 of appendix A to this part.
(d) Non-load-based volumetric flow and NOX emission rate
or NOX concentration data (operational bins not used). The
procedures in this paragraph, (d), apply only to affected units that do
not
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produce electrical output (in megawatts) or thermal output (in klb/hr of
steam) and for which operational bins are not used. For each hour of
missing volumetric flow rate data, NOX emission rate data, or
NOX concentration data used to determine NOX mass
emissions:
(1) Whenever prior quality-assured data exist at the time of the
missing data period, the owner or operator shall substitute, by means of
the automated data acquisition and handling system, for each hour of
missing data, the arithmetic average of all of the prior quality-assured
hourly average flow rates or NOX emission rates or
NOX concentrations.
(2) Whenever no prior quality-assured flow rate, NOX
emission rate, or NOX concentration data exist, the owner or
operator shall, as applicable, substitute for each hour of missing data,
the maximum potential flow rate as specified in section 2.1.4.1 of
appendix A to this part or the maximum potential NOX emission
rate or the maximum potential NOX concentration as specified
in section 2.1.2.1 of appendix A to this part.
[64 FR 28601, May 26, 1999, as amended at 67 FR 40433, June 12, 2002]