Multiple parties in the offshore oil and gas (O&G) sector have asked the EPA to amend the national emissions standards for hazardous air pollutants (NESHAP) for stationary reciprocating internal combustion engines (RICE) so that such engines used on offshore facilities are held to using management practice air standards rather than numeric emissions limits.
June 2012 proposal
Stationary RICE engines generate electricity and power equipment at industrial, agricultural, O&G production, power generation, and other facilities. The EPA estimates that there are over 1 million of these engines in the country, many of which are subject to the NESHAP. On June 7, 2012, the Agency proposed amendments to the existing RICE NESHAP, including an alternative method to demonstrate compliance with the formaldehyde emissions limit, an exemption from emissions limits for emergency engines that operate for no more than 100 hours per year, and a management practice standard rather than a numeric emissions limit for certain engines in remote areas of Alaska.
The June 2012 proposal did not contain or contemplate regulation of RICE in offshore facilities. According to the EPA, the RICE NESHAP does not “on its face” apply to mobile sources, including marine vessels. However, the Agency’s Outer Continental Shelf (OCS) air regulations (40 CFR Part 55) specify that vessels are OCS sources when they are (1) permanently or temporarily attached to the seabed and erected thereon and used for the purpose of exploring, developing, or producing resources; or (2) physically attached to an OCS facility, in which case, only the stationary source aspects of the vessel are regulated.
Management practice standard
Based on the OCS regulations, the American Petroleum Institute, the Alaska Oil and Gas Association, and others requested that any marine vessel that becomes subject to the RICE NESHAP be held to maintenance-based management practices similar to those the EPA has proposed for engines in remote areas. Those management practices include changing the oil and filter, inspecting the air cleaner or spark plugs, and inspecting all hoses and belts within specified intervals. Facilities also have the option of using an oil analysis program to extend the oil change requirement.
Technological feasibility
Under the Clean Air Act, the EPA has the option to require that nonmajor (area) sources of hazardous air pollutants (HAPs) comply with generally available control technology (GACT) requirements that typically involve management practices rather than the maximum achievable control technology (MACT) standards that apply to major sources and typically involve numeric emissions limits for HAPs.
The EPA states that it is considering both the recommendation by the O&G sector and the technological feasibility of requiring that RICE on the OCS meet numeric emissions limits. The Agency has set a November 2, 2012, deadline for receipt of public comments on these issues.
EPA’s notice on the possible inclusion of offshore engines in the RICE NESHAP was published in the October 3, 2012, FR.