(a) The owner or operator shall install, calibrate, and maintain a continuous emissions monitoring system (CEMS) to continuously monitor the exhaust sulfur dioxide (SO2) emissions from Waste Heat Boiler - CDS Stack (EPN E-6BN) in accordance with the requirements of 40 Code of Federal Regulations (CFR) §60.13, 40 CFR Part 60, Appendix B, Performance Specification 2 and 6, for SO2, and 40 CFR Part 60, Appendix F, quality assurance procedures.
(b) For days when EPN CFL (Combined Flare) is used to combust tail gas, the owner or operator shall monitor the sulfur content of the carbon black oil feedstock and produced carbon black, as well as the production rate of the carbon black, as follows:
  (1) measure twice per day at least four hours apart the sulfur content by weight of the carbon black oil in the feed to each production unit according to the requirements of §112.225 of this title (relating to Approved Test Methods);
  (2) unless the sulfur content of the carbon black produced is assumed to be zero in the calculation of SO2 emissions from the flare, for each grade of carbon black produced, measure daily the sulfur content by weight of the carbon black produced by each carbon black production unit according to the requirements of §112.225 of this title; and
  (3) determine hourly the amount of each grade of carbon black produced by each carbon black production unit.
(c) The owner or operator shall install, calibrate, maintain, and operate one or more totalizing fuel flow meters, with an accuracy of ±5%, to continuously measure the feed rate of carbon black oil feedstock supplied to each carbon black production unit.
(d) The owner or operator shall install, calibrate, maintain, and operate totalizing tail gas flow meters, with an accuracy of ±5%, to continuously measure the volumetric flow rate of tail gas to EPN CFL (Combined Flare).
(e) Continuous monitoring data collected in accordance with requirements in this subsection must undergo an appropriate quality assurance and quality control process and be validated for at least 95% of the time that the monitored emission point has emissions; an owner or operator must utilize an appropriate data substitution process based on the most accurate methodology available, which is at least equivalent to engineering judgement, to obtain all missing or invalidated monitoring data for the remaining period the monitored emission point has emissions.
(f) The owner or operator shall calculate SO2 emissions from EPN CFL (Combined Flare) from all production units using the equation below to demonstrate compliance with the emission requirements of §112.222 of this title (relating to Control Requirements).
Attached Graphic
(g) Emissions of SO2 from each EPN specified under §112.222 of this title during any block one-hour period must be calculated on a block one-hour average.
(h) The owner or operator shall calculate SO2 emissions generated by each production unit using the following equation.
Attached Graphic
(i) Minor modifications to monitoring methods may be approved by the executive director. Monitoring methods other than those specified in this section may be used if approved by the executive director and validated by 40 CFR Part 63, Appendix A, Test Method 301. For the purposes of this subsection, substitute "executive director" in each place that Test Method 301 references "administrator." These validation procedures may be waived by the executive director or a different protocol may be granted for site-specific applications. Minor modifications that may be approved under this subsection include increases in the frequency of monitoring and the replacement of parametric monitoring with direct emissions monitoring with a CEMS provided appropriate quality assurance control, accuracy specifications, and data validation requirements are specified and no less stringent than monitoring requirements for a comparable EPN in this division.

Source Note: The provisions of this §112.223 adopted to be effective October 27, 2022, 47 TexReg 6985