| (B) the monitor shall initially and at a minimum quarterly thereafter be subjected to a cylinder gas audit per 40 CFR Part 60, Appendix B, Performance Specification 2, Section 16 to assess system bias and ensure accuracy; (C) the measured concentration shall be used in combination with flow rate determined in accordance with subparagraph (D) of this paragraph to determine the hourly HRVOC emission rate; (D) the following parameter monitoring requirements are used in lieu of the requirements of subsection (a)(1) or (2) of this section: (i) the owner or operator must install, calibrate, maintain, and operate according to manufacturer's recommendations, a continuous monitoring system on the vent or in the associated process systems sufficient to determine the volumetric flow; and (ii) if volumetric flow rate is not monitored directly, the owner or operator must determine through engineering calculations, manufacturer's information, or actual testing the correlation between the monitored parameter and the volumetric flow rate; and (E) the owner or operator complies with the requirements for a written monitoring plan specified in subsection (a)(4) of this section. (2) Process knowledge, including scientific calculations and other process monitoring data sufficient to demonstrate compliance status, may be used to determine maximum potential HRVOC hourly emission data. Types of vent gas streams for which process knowledge may be used in lieu of testing are: (A) analyzer vents; (B) steam system vents; (C) vent gas streams where there is no HRVOC present except during emissions events; or (D) degassing safety devices, as defined in §115.720 of this title (relating to Applicability and Definitions). (c) Affected pressure relief valves not controlled by a flare shall be monitored as follows. (1) Install, calibrate, maintain, and operate according to manufacturer's recommendations, a continuous monitoring system on the pressure relief valve or in the associated process systems sufficient to determine: (A) the time and duration of each pressure relief event; (B) the status of the pressure relief valve as either: (i) open or closed to the atmosphere; or (ii) the percentage the valve is open to the atmosphere; and (C) the volumetric flow rate during a pressure relief event. (i) If volumetric flow rate is not monitored directly, the owner or operator must determine through engineering calculations, manufacturer's information, or actual testing the correlation between the monitored parameter and the percentage the pressure relief valve is open to the atmosphere to the volumetric flow rate. (ii) If the monitoring system only indicates an open or closed status as specified in subparagraph (B)(i) of this paragraph, the owner or operator must assume the pressure relief valve is 100% open during a pressure relief event for purposes of calculating volumetric flow rate. (2) For purposes of determining compliance with the control requirement of §115.722(a) - (c) of this title during pressure relief events, the owner or operator may use process knowledge, including scientific calculations and other process monitoring data, to determine HRVOC emission rates. The volumetric flow rate determined in accordance with paragraph (1)(C) of this subsection shall be used in combination with the process knowledge to determine HRVOC emission rates. (3) The owner or operator shall develop, implement, and follow a written monitoring plan to satisfy the requirements of paragraphs (1) and (2) of this subsection. The monitoring plan must include: (A) specifications for all monitors used to satisfy the requirements of paragraphs (1) and (2) of this subsection; (B) all engineering calculations, manufacturer's information, or actual testing supporting the correlation of the monitored parameters to actual volumetric flow rate specified in paragraph (1)(C)(i) of this subsection; (C) supporting documentation of the actual testing or process knowledge used to determine HRVOC emissions as provided in paragraph (2) of this subsection; (D) at a minimum, quarterly inspections of all pressure relief valves and associated monitors to insure proper operation per the manufacturer's specifications; and (E) a list identifying all pressure relief valves in HRVOC service subject to the requirements of this subsection. (4) Upon written request by the executive director, the monitoring plan required under paragraph (3) of this subsection must be submitted within 30 days for review. The executive director may require additional or alternative monitoring requirements. (d) Except as specified in subsections (e) - (k) of this section, the owner or operator of an affected flare must conduct continuous monitoring, to demonstrate compliance with §115.722(a) - (d) of this title as follows: (1) install, calibrate, maintain, and operate a continuous flow monitoring system capable of measuring the flow rate over the full potential range of operation. The executive director may approve alternative means of determining the flare flow rate for a period of time not to exceed 1.0% of the annual operating time of the flare. The monitoring system must be capable of measuring the entire gas stream flow to the flare (i.e., all vent gas and supplemental fuel sources) and may consist of one or more flow measurements at one or more header locations. For correcting flow rate to standard conditions (defined as 68 degrees Fahrenheit and 760 millimeters of mercury (mm Hg)), temperature and pressure in the main flare header must be monitored continuously. The monitors must be calibrated to meet accuracy specifications as follows: (A) the temperature monitor must be calibrated annually to within ±2.0% at absolute temperature; (B) the pressure monitor must be calibrated annually to within ±5.0 mm Hg; and (C) the flow monitor, or velocity monitor used to determine flow rate, must be initially calibrated, prior to installation, to demonstrate accuracy to within 5.0% at flow rates equivalent to 30%, 60%, and 90% of monitor full scale. After installation, the flow monitor or velocity monitor must be calibrated annually according to manufacturer's specifications; (2) install, calibrate, maintain, and operate an on-line analyzer system capable of determining HRVOC at least once every 15 minutes. The on-line analyzer system must also be capable of measuring, at least once every 15 minutes, other potential constituents (e.g., hydrogen, nitrogen, methane, and carbon dioxide, and volatile organic compounds (VOC) other than HRVOCs) sufficient to determine the molecular weight and net heating value of the gas combusted in the flare to within 5.0%. Samples must be collected from a location on the main flare header such that the measured constituents, including any supplementary fuel, are representative of the combined gas combusted in the flare system. Net heating value of the gas combusted in the flare must be calculated according to the equation given in 40 CFR §60.18(f)(3) as amended through October 17, 2000 (65 FR 61744). The samples must be used to demonstrate continuous compliance with the requirements of §115.722(a) - (d) of this title. Pilot gas may not be included in the determination of the net heating value. (A) Calibration of the on-line analyzer shall be as follows: (i) for the HRVOC constituents, follow the procedures and requirements of Section 10.0 of 40 CFR Part 60, Appendix B, Performance Specification 9, as amended through October 17, 2000 (65 FR 61744), except that the multi-point calibration procedure in Section 10.1 of Performance Specification 9 must be performed at least once every calendar quarter instead of once every month, and the mid-level calibration check procedure in Section 10.2 of Performance Specification 9 must be performed at least once every calendar week instead of once every 24 hours. The calibration gases used for calibration procedures must be in accordance with Section 7.1 of Performance Specification 9; (ii) for the constituents monitored to determine net heating value and molecular weight, the owner or operator may elect to follow either the calibration procedures specified for HRVOC constituents in clause (i) of this subparagraph or the calibration procedures recommended by the analyzer manufacturer. If the owner or operator elects to follow manufacturer's recommended procedures: (I) those calibration procedures must include, at a minimum, single point calibration checks at least once every calendar week to meet the acceptance criteria specified in Section 10.2 of Performance Specification 9 with certified standards of the top two non-HRVOC constituents affecting molecular weight and net heating value; and Cont'd... |
