Posted on July 29, 2014 by Carolyn Brown
In an Advanced Notice of Proposed Rulemaking (ANPRM) published in the July 17, 2014 Federal Register, EPA requests public input on reduction of emissions from existing municipal solid waste (MSW) landfills. “Landfill gas” (LFG) contains methane, carbon dioxide and nonmethane organic compounds (NMOC). NMOC includes various organic hazardous air pollutants and volatile organic compounds and was the focus of EPA’s initial landfill emission regulations in 1996. However, the current driver for EPA’s focus on this source category is the President’s Climate Action Plan and the March 2014 Strategy to Reduce Methane Emissions.
With respect to landfills, the Methane Strategy calls for EPA to update its rules to reduce emissions from new, modified, and reconstructed landfills; to explore options to reduce emissions from existing landfills; and to encourage energy recovery from LFG through voluntary programs. The ANPRM addresses the existing landfill component of the strategy. EPA notes that LFG is typically composed of roughly equal parts of methane and carbon dioxide and less than one percent of NMOC. Methane has a global warming potential 25 times greater than carbon dioxide and is also identified as a precursor to ground-level ozone.
MSW landfills are a source category for which EPA has issued new source performance standards (NSPS) under Section 111(b) and emission guidelines under Section 111(d) of the Clean Air Act. Both the NSPS and the emission guidelines were promulgated in 1996. The designated facilities to which the guidelines apply are existing MSW landfills for which construction, reconstruction or modification commenced before May 30, 1991. EPA required state plans to control MSW landfills of a certain size and NMOC emission rate if the landfill had accepted waste at any time since November 8, 1987, or had additional design capacity available for future waste deposition.
In the ANPRM, EPA states that it is not statutorily obligated to conduct review of emission guidelines but has the discretionary authority to do so when appropriate. Despite the focus on the methane strategy, the circumstances EPA identifies for making the review appropriate here are “changes in the landfills industry and changes in size, ownership, and age of landfills” since the emission guidelines were promulgated in 1996. The ANPRM states that any changes to the emission guidelines would apply to landfills that accepted waste after November 8, 1987, and that commenced construction, reconstruction or modification prior to the publication of proposed revisions to the landfill NSPS. Landfills currently subject to the 1996 NSPS would have to comply with those requirements as well as any more stringent requirements in the applicable revised state plan or federal plan implementing the revised Section 111(d) guidelines.
Among the topics on which EPA requests comment are the following: (1) extent to which reduction in methane emissions should be taken into account in revising the guidelines; (2) possible changes in the regulatory framework such as eliminating or reducing the design capacity threshold for applicability; (3) criteria and timing for capping or removing the landfill gas collection and control system (GCCS); (4) emission reduction techniques and GCCS best management practices; (5) alternative monitoring and reporting requirements; and (6) what constitutes sufficient LFG treatment, including use of LFG as fuel. Comments are due September 15, 2014.