EPA Refinery MACT Residual Risk
January 13, 2009, EPA posted on its web site Final Amendments to the National Emission Standards for Hazardous Air Pollutants From Petroleum Refineries, codified in 40 CFR 63, Subpart CC. The U.S. EPA is required to review the developments in practices, processed, and control technologies every eight years and update national emissions standards to address the "residual risk" after implementation of the original standards. The residual risk amendments will become effective upon the date of publication of the final rules in the Federal Register.
New Requirements for Group 1 Storage Vessels:
- All Group 1 external floating roof (EFR) storage tanks will be required to meet the requirements of 40 CFR part 63, subpart W, including the inspection, recordkeeping, and reporting requirements. Subpart WW requires installation of controls for guide poles and other openings in EFR storage tanks. Interal floating roof (IFR) storage vessels are not required to install guide pole controls or other fitting controls.
New Requirements for Heat Exchange Systems:
- Heat exchange systems that are in organic HAP service at new and existing ources will be requires to conduct monthly sampling and analyses for VOC in the cooling water using the Texas Commission on Environmental Quality's (TCEQ) Modified El Paso method, Revision Number One, dated January 2003. The amendments to Refinery MACT I require the repair of leaks in heat exchangers in organic HAP service within 45 days of the sampling event in which the leak is detected, unless a delay in repair is allowed. Delay in repair of the leak is allowed until the next shutdown if the repair of the leak requires the process unit served by the leaking heat exchanger to be shut down and the total strippable VOC concentration is less than 62 ppmv and if critical parts or personnel are not available. The owner or operator is required to continue monitoring and to repair the heat exchanger within 30 days if sampling results show that the leak exceeds 62 ppmv total strippable VOC.
- For new sources, a leak is defined as 3.1 ppmv total strippable VOC collected via the Modified El Paso method.
- For existing sources, a leak is defined as 6.2 ppmv total strippable VOC collected via the Modified El Paso method.
All Group 1 storage vessels and heat exchange systems at existing refineries must be in compliance within 36 months after the Final Amendments are published in the Federal Register.
Several other importand revisions were made to clarify the original intent of the rule:
- Replacing "gasoline loading rack" with "Group 1 gasoline loading rack" in 63.650(a).
- Finalizing proposed amendments to cross-references to 40 CFR 63, Subparts R and Y, as well as Tables 4 and 5 of Refinery MACT I.
- Amending Table 6 of Refinery MACT I to reflect amendments that have been made to the General Provisions of Part 63.
- Deleting methyl ethyl ketone from Tables 1 and 7 since it has been delisted as a HAP.
- Clarifying rule applicability by listing the actual date of promulgation for the original rule.
- Clarifying compliance options for equipment leaks and storage vessels when other rules overlap with the requirements of Refinery MACT I.
- Also, the EPA opted not to promulgate changes to Refinery MACT I that would include performance standards and monitoring requirements for enhanced biological units to treat Group 1 wastewater streams.