§  75.34 Units with add-on emission controls.

(a) The owner or operator of an affected unit equipped with add-on SO2 and/or NOX emission controls shall use one of the following options for each hour in which quality-assured data from the outlet SO2 and/or NOX monitoring system(s) are not obtained:

(1) The owner or operator may use the missing data substitution procedures as specified for all affected units in §§  75.31 through 75.33 to substitute data for each hour in which the add-on emission controls are operating within the proper parametric ranges specified in the quality assurance/quality control program for the unit, required by section 1 in appendix B of this part. The designated representative shall document in the quality assurance/ quality control program the ranges of the add-on emission control operating parameters that indicate proper operation of the controls. The owner or operator shall, for each missing data period, record data to verify the proper operation of the SO2 or NOX add-on emission controls during each hour, as described in paragraph (d) of this section. In addition, under §  75.64(c), the designated representative shall submit a certified verification of the proper operation of the SO2 or NOX add-on emission control for each missing data period at the end of each quarter.

(2) The designated representative may petition the Administrator under §  75.66 to replace the maximum recorded value in the last 720 quality-assured monitor operating hours with a value corresponding to the maximum controlled emission rate (an emission rate recorded when the add-on emission controls were operating) recorded during the last 720 quality-assured monitor operating hours. For such a petition, the designated representative must demonstrate that the following conditions are met: the monitor data availability, calculated in accordance with §  75.32, for the affected unit is below 90.0 percent and parametric data establish that the add-on emission controls were operating properly (i.e., within the range of operating parameters provided in the quality assurance/ quality control program) during the time period under petition.

(3) The designated representative may petition the Administrator under §  75.66 for approval of site-specific parametric monitoring procedure(s) for calculating substitute data for missing SO2 pollutant concentration, NOX pollutant concentration, and NOX emission rate data in accordance with the requirements of paragraphs (b) and (c) of this section and appendix C to this part. The owner or operator shall record the data required in appendix C to this part, pursuant to §  75.55(b) or §  75.58(b), as applicable.

(b) For an affected unit equipped with add-on SO2 emission controls, the designated representative may petition the Administrator to approve a parametric monitoring procedure, as described in appendix C of this part, for calculating substitute SO2 concentration data for missing data periods. The owner or operator shall use the procedures in §§  75.31, 75.33, or 75.34(a) for providing substitute data for missing SO2 concentration data unless a parametric monitoring procedure has been approved by the Administrator.

(1) Where the monitor data availability is 90.0 percent or more for an outlet SO2 pollutant concentration monitor, the owner or operator may calculate substitute data using an approved parametric monitoring procedure.

(2) Where the monitor data availability for an outlet SO2 pollutant concentration monitor is less than 90.0 percent, the owner or operator shall calculate substitute data using the procedures in §  75.34(a) (1) or (2), even if the Administrator has approved a parametric monitoring procedure.

(c) For an affected unit with NOX add-on emission controls, the designated representative may petition the Administrator to approve a parametric monitoring procedure, as described in appendix C of this part, in order to calculate substitute NOX emission rate data for missing data periods. The owner or operator shall use the procedures in §  75.31 or 75.33 for providing substitute data for missing NOX2 emission rate data prior to receiving the Administrator's approval for a parametric monitoring procedure.

(1) Where monitor data availability for a NOX continuous emission monitoring system is 90.0 percent or more, the owner or operator may calculate substitute data using an approved parametric monitoring procedure.

(2) Where monitor data availability for a NOX continuous emission monitoring system is less than 90.0 percent, the owner or operator shall calculate substitute data using the procedure in §  75.34(a) (1) or (2), even if the Administrator has approved a parametric monitoring procedure.

(d) The owner or operator shall keep records of information as described in subpart F of this part to verify the proper operation of the SO2 or NOX emission controls during all periods of SO2 or NOX emission missing data. The owner or operator shall provide these records to the Administrator or to the EPA Regional Office upon request. Whenever such data are not provided or such data do not demonstrate that proper operation of the SO2 or NOX add-on emission controls has been maintained in accordance with the range of add-on emission control operating parameters reported in the quality assurance/quality control program for the unit, the owner or operator shall substitute the maximum potential NOX emission rate, as defined in §  72.2 of this chapter, to report the NOX emission rate, and either the maximum hourly SO2 concentration recorded by the inlet monitor during the previous 720 quality-assured monitor operating hours, if available, or the maximum potential concentration for SO2, as defined by section 2.1.1.1. of appendix A of this part, to report SO2 concentration for each hour of missing data until information demonstrating proper operation of the SO2 or NOX emission controls is available.

[60 FR 26567, May 17, 1995, as amended at 61 FR 59160, Nov. 20, 1996; 64 FR 28604, May 26, 1999]