(a) Totalizing fuel flow meters. The owner or operator of units listed in this subsection shall install, calibrate, maintain, and operate a totalizing fuel flow meter, with an accuracy of ± 5%, to individually and continuously measure the gas and liquid fuel usage. A computer that collects, sums, and stores electronic data from continuous fuel flow meters is an acceptable totalizer. The owner or operator must continuously operate the totalizing fuel flow meter at least 95% of the time when the unit is operating during a calendar year. For the purpose of compliance with this subsection for units having pilot fuel supplied by a separate fuel system or from an unmonitored portion of the same fuel system, the fuel flow to pilots may be calculated using the manufacturer's design flow rates rather than measured with a fuel flow meter. The calculated pilot fuel flow rate must be added to the monitored fuel flow when fuel flow is totaled.
  (1) The units are the following units subject to §117.405 (relating to Emission Specifications for Reasonably Available Control Technology (RACT)) or §117.410 of this title (relating to Emission Specifications for Eight-Hour Attainment Demonstrations):
    (A) boilers (excluding wood-fired boilers that must comply by maintaining records of fuel usage as required in §117.445(f) of this title (relating to Notification, Recordkeeping, and Reporting Requirements) or monitoring in accordance with paragraph (2)(A) of this subsection);
    (B) process heaters;
    (C) duct burners used in turbine exhaust ducts;
    (D) stationary, reciprocating internal combustion engines;
    (E) stationary gas turbines;
    (F) lime kilns
    (G) brick and ceramic kilns;
    (H) heat treating furnaces;
    (I) reheat furnaces;
    (J) lead smelting blast (cupola) and reverberatory furnaces;
    (K) glass and fiberglass/mineral wool melting furnaces;
    (L) incinerators (excluding vapor streams resulting from vessel cleaning routed to an incinerator, provided that fuel usage is quantified using good engineering practices, including calculation methods in general use and accepted in new source review permitting in Texas. All other fuel and vapor streams must be monitored in accordance with this subsection);
    (M) gas-fired glass, fiberglass, and mineral wool curing ovens;
    (N) natural gas-fired ovens and heaters; and
    (O) natural gas-fired dryers used in organic solvent, printing ink, clay, brick, ceramic, and calcining and vitrifying processes.
  (2) The following are alternatives to the fuel flow monitoring requirements of paragraph (1) of this subsection.
    (A) Units operating with a nitrogen oxides (NOX ) and diluent continuous emissions monitoring system (CEMS) under subsection (f) of this section may monitor stack exhaust flow using the flow monitoring specifications of 40 Code of Federal Regulations (CFR) Part 60, Appendix B, Performance Specification 6 or 40 CFR Part 75, Appendix A.
    (B) Units that vent to a common stack with a NOX and diluent CEMS under subsection (f) of this section may use a single totalizing fuel flow meter.
    (C) Diesel engines operating with run time meters may meet the fuel flow monitoring requirements of this subsection through monthly fuel use records maintained for each engine.
    (D) Stationary reciprocating internal combustion engines and gas turbines equipped with a continuous monitoring system that continuously monitors horsepower and hours of operation are not required to install totalizing fuel flow meters. The continuous monitoring system must be installed, calibrated, maintained, and operated according to manufacturers' recommended procedures.
(b) Oxygen (O2 ) monitors.
  (1) The owner or operator shall install, calibrate, maintain, and operate an O2 monitor to measure exhaust O2 concentration on the following units operated with an annual heat input greater than 2.2(1011 ) British thermal units per year (Btu/yr):
    (A) boilers with a rated heat input greater than or equal to 100 million British thermal units per hour (MMBtu/hr); and
    (B) process heaters with a rated heat input greater than or equal to 100 MMBtu/hr, except:
      (i) as provided in subsection (g) of this section; and
      (ii) for process heaters operating with a carbon dioxide (CO2 ) CEMS for diluent monitoring under subsection (f) of this section.
  (2) The O2 monitors required by this subsection are for process monitoring (predictive monitoring inputs, boiler trim, or process control) and are only required to meet the location specifications and quality assurance procedures referenced in subsection (f) of this section if O2 is the monitored diluent under that subsection. However, if new O2 monitors are required as a result of this subsection, the criteria in subsection (f) of this section should be considered the appropriate guidance for the location and calibration of the monitors.
(c) NOX monitors.
  (1) The owner or operator of units listed in this paragraph shall install, calibrate, maintain, and operate a CEMS or predictive emissions monitoring system (PEMS) to monitor exhaust NOX . The units are:
    (A) units with a rated heat input greater than or equal to 100 MMBtu/hr that are subject to §117.405(a) or (b) or §117.410(a) of this title;
    (B) stationary gas turbines with a megawatt (MW) rating greater than or equal to 30 MW operated more than 850 hours per year;
    (C) units that use a chemical reagent for reduction of NOX;
    (D) units that the owner or operator elects to comply with the NOX emission specifications of §117.405(a) or (b) of this title or §117.410(a) of this title using a pound per MMBtu (lb/MMBtu) limit on a 30-day rolling average;
    (E) lime kilns; and
    (F) brick kilns and ceramic kilns.
  (2) The following units are not required to install CEMS or PEMS under this subsection;
    (A) units subject to the NOX CEMS requirements of 40 CFR Part 75; and
    (B) stationary diesel engines equipped with selective catalytic reduction (SCR) systems that meet the following criteria.
      (i) The SCR system must use a reductant other than the engine's fuel.
      (ii) The SCR system must operate with a diagnostic system that monitors reductant quality and tank levels.
      (iii) The diagnostic system must alert owners or operators to the need to refill the reductant tank before it is empty or to replace the reductant if the reductant does not meet applicable concentration specifications.
      (iv) If the SCR system uses input from an exhaust NOX sensor (or other sensor) to alert owners or operators when the reductant quality is inadequate, the reductant quality does not need to be monitored separately by the diagnostic system.
      (v) The reductant tank level must be monitored in accordance with the manufacturer's design to demonstrate compliance with this subparagraph.
      (vi) The method of alerting an owner or operator must be a visual or audible alarm.
  (3) The owner or operator shall use one of the following methods to provide substitute emissions compliance data during periods when the NOX monitor is off-line:
    (A) if the NOX monitor is a CEMS:
      (i) subject to 40 CFR Part 75, use the missing data procedures specified in 40 CFR Part 75, Subpart D (Missing Data Substitution Procedures); or
      (ii) subject to 40 CFR Part 75, Appendix E, use the missing data procedures specified in 40 CFR Part 75, Appendix E, §2.5 (Missing Data Procedures);
    (B) use 40 CFR Part 75, Appendix E monitoring in accordance with §117.1340(d) of this title (relating to Continuous Demonstration of Compliance);
    (C) if the NOX monitor is a PEMS:
      (i) use the methods specified in 40 CFR Part 75, Subpart D; or
      (ii) use calculations in accordance with §117.8110(b) of this title (relating to Emission Monitoring System Requirements for Utility Electric Generation Sources); or
    (D) the maximum block one-hour emission rate as measured during the initial demonstration of compliance required in §117.435(e) of this title (relating to Initial Demonstration of Compliance).
Cont'd...