EPA proposes national uniform emission standards for heat exchange systems

published in McAfee & Taft RegLINC | April 1, 2012

By Robert Joyce

On January 6, 2012, the EPA issued a Notice of Proposed Rulemaking (proposed rule) in which it proposed amendments to the NESHAP/NSPS standards applicable to hydrocarbon emissions from heat exchange systems for petroleum refineries. However, most significantly, the EPA’s notice includes a proposal to create national uniform standards for heat exchange systems that would apply to many facilities other than refineries. The EPA plans to “reference” these new uniform standards as it “revise[s] in the future NESHAP or source performance standards for individual source categories that have heat exchange systems.” As such, the uniform standards could affect many different types of manufacturers, including manufacturers of petrochemicals, chemicals, polymers, plastics and specialty chemicals – not just refineries.

In addition to creating the new uniform standards, the proposal provides refineries with an alternative option for complying with the standards for heat exchange systems, and would allow refineries to reduce monitoring frequency by meeting a more stringent definition for “leaks.”

The EPA first published its MACT (maximum achievable control technology) standards for petroleum refin-eries (40 CFR Part 63 Subpart CC) in 1995. 60 Fed. Reg. 43620 (8/18/1995). These standards were amended in 2009 with the adoption of the MACT standards for heat exchange systems at petroleum refineries. 74 Fed. Reg. 55670 (10/28/2009). The proposed rule would amend 40 CFR Part 63 Subpart CC, and create a new section – 40 CFR Part 65, subpart L – containing the uniform standards for heat exchange systems. As noted above, the EPA’s plan is to reference these uniform standards “as appropriate … [in] future NESHAP for major or area source categories” in 40 CFR Parts 60, 61, and 65.

The proposed rule was prompted by a December 29, 2009, request from the American Petroleum Institute (API) for the EPA to reconsider 10 sections of the 2009 MACT standards for heat exchange systems at petroleum refineries. Of the issues raised, the EPA only agreed to reconsider three: 1) 63.640(n) – overlap provisions for storage vessels, 2) 63.646 – deck fitting control requirements for vessels with internal floating roofs, and 3) reports for storage vessels also subject to 40 CFR Part 61, subpart Y.

As for other refinery-specific changes in the proposed rule, the EPA stated that it would continue to require monthly leak monitoring for heat exchange systems at existing sources, with an action level of 6.2 ppmv total strippable hydrocarbons in stripping gas collected via the TCEQ Modified El Paso Method, Revision 1 (El Paso Method); for new sources, the action level of 3.1 ppmv would also remain. However, the EPA proposed alternative leak action levels based on analysis of total strippable hydrocarbons in cooling water collected and analyzed according to certain SW-846/ASTM methods. The new alternative action levels are 80 ppbw for existing sources and 40 ppbw for new sources. The EPA also retained the “delay of repair” action level of 62 ppmv total strippable hydrocarbons collected via the El Paso Method, and proposed an 800 ppbw action level for total strippable hydrocarbons in the cooling water collected and analyzed by the SW-846/ASTM methods. In addition, the EPA proposed that refineries be allowed to monitor on a quarterly basis instead of monthly if they use the lower leak action levels of 3.1 ppmv via the El Paso Method or the 40 ppbw via the SW-846/ASTM methods.

As for the new uniform standards, the EPA proposed adding two new subparts to 40 CFR Part 65: Subpart H – National Uniform Emissions Standards General Provisions, and Subpart L – National Uniform Emissions Standards for Heat Exchange Systems. Subpart H contains provisions that would apply to all sources subject to current or newly promulgated uniform standards such as definitions and provisions for incorporation by reference, as well as determining whether a uniform standard applies to a particular regulated source. Subpart L of the proposed uniform standards is directed at heat exchange systems, and applies to “the control of air emissions from heat exchange systems for which another subpart references the use of this subpart for such air emission control.” A heat exchange system is defined as “a device or collection of devices used to transfer heat from process fluids to water without intentional direct contact to of the process fluids with the water. . . and to transport and/or cool the water in a closed loop recirculation system (cooling tower system) or a once through system (e.g. river or pond water).” The proposed subpart sets forth the required monitoring and repair requirements including monitoring locations, methods, frequency, and action levels. The new regulations also set forth the recordkeeping, notification and reporting requirements applicable to covered heat exchange systems.