Document ID: EPA-HQ-OAR-2002-0058-3961
Agency: epa
Document Type: Supporting & Related Material
Title: 
Posted Date: 2020-08-24T04:00Z

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

§ 63.7525  What are my monitoring, installation, operation, and maintenance requirements?
    (a) If your boiler or process heater is subject to a CO emission limit in Tables 1, 2, or 11 through 13 to this subpart, you must install, operate, and maintain an oxygen analyzer system, as defined in § 63.7575, or install, certify, operate and maintain continuous emission monitoring systems for CO and oxygen (O2) (or carbon dioxide (CO2)) according to the procedures in paragraphs (a)(1) through (6) of this section.
    (1) Install the CO CEMS including an O2 (or CO2) analyzer by the compliance date specified in § 63.7495. The CO and O2 (or CO2) levels shall be monitored at the same location at the outlet of the boiler or process heater. An owner or operator may  determine compliance with the CO emissions limit using a CO2 analyzer as the diluent monitor . If a CO2 analyzer is used as the diluent monitor, EPA Method 19 F-factors for the fuel type(s) being burned in the unit and EPA Method 19 equations must be used to calculate the emissions corrected to 3 percent O2 using the measured CO2 percentage, and must also take into account that the 3 percent oxygen correction is to be done on a dry basis. The  equations used to calculate the emissions,  must also account for any CO2 being added to, or removed from, the emissions gas stream as a result of limestone injection, scrubber media, etc.  The methodology used to calculate the CO emissions and the methodology used to account for any CO2 being added to, or removed from the emissions gas stream shall be detailed and approved in the site-specific monitoring plan developed according to § 63.7505(d).
    (2) To demonstrate compliance with the applicable alternative CO CEMS emission standard listed in Tables 1, 2, or 11 through 13 to this subpart, you must install, certify, operate, and maintain a CO CEMS and an oxygen analyzer according to the applicable procedures under Performance Specification 4, 4A, or 4B at 40 CFR part 60, appendix B; part 75 of this chapter (if an CO2 analyzer is used); the site-specific monitoring plan developed according to § 63.7505(d); and the requirements in § 63.7540(a)(8) and paragraph (a) of this section. Any boiler or process heater that has a CO CEMS that is compliant with Performance Specification 4, 4A, or 4B at 40 CFR part 60, appendix B, a site-specific monitoring plan developed according to § 63.7505(d), and the requirements in § 63.7540(a)(8) and paragraph (a) of this section must use the CO CEMS to comply with the applicable alternative CO CEMS emission standard listed in Tables 1, 2, or 11 through 13 to this subpart.
    (i) You must conduct a performance evaluation of each CO CEMS according to the requirements in § 63.8(e) and according to Performance Specification 4, 4A, or 4B at 40 CFR part 60, appendix B.
    (ii) During each relative accuracy test run of the CO CEMS, you must collect emission data for CO concurrently  using both the CO CEMS and Method 10, 10A, or 10B at 40 CFR part 60, appendix A-4. The relative accuracy testing must be conducted at representative operating conditions.
    (iii) You must follow the quality assurance procedures (e.g., quarterly accuracy determinations and daily calibration drift tests) of Procedure 1 of appendix F to part 60. The measurement span value of the CO CEMS must be two times the applicable CO emission limit, expressed as a concentration.
    (iv) Any CO CEMS that does not comply with § 63.7525(a) cannot be used to meet any requirement in this subpart to demonstrate compliance with a CO emission limit listed in Tables 1, 2, or 11 through 13 to this subpart. 
    (v) For a new unit, complete the initial performance evaluation no later than July 30, 2013, or 180 days after the date of initial startup, whichever is later. For an existing unit, complete the initial performance evaluation no later than July 29, 2016.
    (vi) When CO2 is used to correct CO emissions and CO2 is measured on a wet basis, if needed, correct for moisture as follows: Install, operate, maintain, and quality assure a continuous moisture monitoring system for measuring and recording the moisture content of the flue gases, in order to correct the measured hourly volumetric flow rates for moisture when calculating CO concentrations. The following continuous moisture monitoring systems are acceptable: a continuous moisture sensor; an oxygen analyzer (or analyzers) capable of measuring O2 both on a wet basis and on a dry basis; or a stack temperature sensor and a moisture look-up table, i.e., a psychrometric chart (for saturated gas streams following wet scrubbers or other demonstrably saturated gas streams, only). The moisture monitoring system shall include as a component the automated data acquisition and handling system (DAHS) for recording and reporting both the raw data (e.g., hourly average wet-and dry-basis O2 values) and the hourly average values of the stack gas moisture content derived from those data. When a moisture look-up table is used, the moisture monitoring system shall be represented as a single component, the certified DAHS, in the monitoring plan for the unit or common stack.

Tables to Subpart DDDDD of Part 63
1. Proposed revision to footnote "d" of Table 1 to read as follows:
Table 1 to Subpart DDDDD of Part 63 -- Emission Limits for New or Reconstructed Boilers and Process Heaters
    As stated in § 63.7500, you must comply with the following applicable emission limits:
      [Units with heat input capacity of 10 million Btu per hour or greater]
                               *  *  *  *  *  *  *	
d An owner or operator may determine compliance with the carbon monoxide emissions limit using carbon dioxide as a diluent correction in place of oxygen as described in §63.7525(a)(1). EPA Method 19 F-factors and EPA Method 19 equations must be used to generate the appropriate CO2 correction percentage for the fuel type burned in the unit, and must also take into account that the 3% oxygen correction is to be done on a dry basis. The methodology must account for any CO2 being added to, or removed from, the emissions gas stream as a result of limestone injection, scrubber media, etc. This methodology must be detailed in the site-specific monitoring plan developed according to § 63.7505(d).

2. Proposed revision to footnote "c" of Table 2 to read as follows:

Table 2 to Subpart DDDDD of Part 63 -- Emission Limits for Existing Boilers and Process Heaters
    As stated in § 63.7500, you must comply with the following applicable emission limits:
      [Units with heat input capacity of 10 million Btu per hour or greater]
                               *  *  *  *  *  *  *	
                                         
c An owner or operator may determine compliance with the carbon monoxide emissions limit using carbon dioxide as a diluent correction in place of oxygen as described in §63.7525(a)(1). EPA Method 19 F-factors and EPA Method 19 equations must be used to generate the appropriate CO2 correction percentage for the fuel type burned in the unit, and must also take into account that the 3% oxygen correction is to be done on a dry basis. The methodology must account for any CO2 being added to, or removed from, the emissions gas stream as a result of limestone injection, scrubber media, etc. This methodology must be detailed in the site-specific monitoring plan developed according to § 63.7505(d).

3. Proposed revision to footnote "c" of Table 11 to read as follows:

Table 11 to Subpart DDDDD of Part 63 -- Alternative Emission Limits for New or Reconstructed Boilers and Process Heaters that Commenced Construction or Reconstruction after June 4, 2010, and Before May 20, 2011
                               *  *  *  *  *  *  *	

c An owner or operator may determine compliance with the carbon monoxide emissions limit using carbon dioxide as a diluent correction in place of oxygen as described in §63.7525(a)(1). EPA Method 19 F-factors and EPA Method 19 equations must be used to generate the appropriate CO2 correction percentage for the fuel type burned in the unit, and must also take into account that the 3% oxygen correction is to be done on a dry basis. The methodology must account for any CO2 being added to, or removed from, the emissions gas stream as a result of limestone injection, scrubber media, etc. This methodology must be detailed in the site-specific monitoring plan developed according to § 63.7505(d).

4. Proposed revision to footnote "c" of Table 12 to read as follows:

Table 12 to Subpart DDDDD of Part 63 -- Alternative Emission Limits for New or Reconstructed Boilers and Process Heaters that Commenced Construction or Reconstruction after May 20, 2011, and Before December 23, 2011
                               *  *  *  *  *  *  *	

c An owner or operator may determine compliance with the carbon monoxide emissions limit using carbon dioxide as a diluent correction in place of oxygen as described in §63.7525(a)(1). EPA Method 19 F-factors and EPA Method 19 equations must be used to generate the appropriate CO2 correction percentage for the fuel type burned in the unit, and must also take into account that the 3% oxygen correction is to be done on a dry basis. The methodology must account for any CO2 being added to, or removed from, the emissions gas stream as a result of limestone injection, scrubber media, etc. This methodology must be detailed in the site-specific monitoring plan developed according to § 63.7505(d).

5. Proposed revision to footnote "c" of Table 13 to read as follows:

Table 13 to Subpart DDDDD of Part 63 -- Alternative Emission Limits for New or Reconstructed Boilers and Process Heaters That Commenced Construction or Reconstruction After December 23, 2011, and Before April 1, 2013
c An owner or operator may determine compliance with the carbon monoxide emissions limit using carbon dioxide as a diluent correction in place of oxygen as described in §63.7525(a)(1). EPA Method 19 F-factors and EPA Method 19 equations must be used to generate the appropriate CO2 correction percentage for the fuel type burned in the unit, and must also take into account that the 3% oxygen correction is to be done on a dry basis. The methodology must account for any CO2 being added to, or removed from, the emissions gas stream as a result of limestone injection, scrubber media, etc. This methodology must be detailed in the site-specific monitoring plan developed according to § 63.7505(d).