The U.S. Environmental Appeals Board on July 14 ordered further briefs to be filed in a case where private citizens are appealing an air permit for a gas-fired power project in Massachusetts of Footprint Power Salem Harbor Development LP.
Four individuals have jointly petitioned the board for review of the Prevention of Significant Deterioration (PSD) permit issued by the Massachusetts Department of Environmental Protection (MassDEP) to Footprint Power Salem Harbor for the construction of a generating facility in Salem, Mass., at the site of shut oil- and coal-fired capacity. The PSD permit was issued on Jan. 30 to Footprint Salem Harbor to construct a 692-MW combined-cycle facility.
The project will use General Electric (GE) Model 107F Series 5 combustion turbines, steam turbine generators, heat recovery steam generators, and air-cooled condensers as well as a variety of pollution control equipment.
Both MassDEP and Footprint have filed responses to the petition. After examination of the petition and responses, the board has determined that supplemental briefing from the U.S. Environmental Protection Agency’s Office of Air and Radiation (OAR) and Office of General Counsel (OGC) on one issue in the case would be helpful. The issue concerns when best available control technology (BACT) must be applied to potential volatile organic compounds (VOCs) emissions from a new major stationary source.
Under the Clean Air Act regulations, a new major stationary source is required “to apply best available control technology for each regulated NSR [New Source Review] pollutant that it would have the potential to emit in significant amounts.” Two critical defined terms in this requirement are “regulated NSR pollutant” and “significant.”
“Regulated NSR pollutants” are defined as including pollutants “for which a national ambient air quality standard has been promulgated,” and designated precursors of such pollutants. Ozone is the subject of a national ambient air quality standard, and the U.S. EPA has designated VOCs and nitrogen oxide as ozone precursors in all attainment and unclassifiable areas. The potential to emit in “significant” amounts is defined for “ozone” as a rate that would equal or exceed “40 tpy [tons per year] of volatile organic compounds or nitrogen oxides.”
Petitioners claim that MassDEP erred by removing a proposed VOCs emission limit from the draft permit. They said the “plain language” of the applicable CAA regulations require that, if the aggregate weight of emissions of all ozone precursors (including VOCs) from a source exceed 40 tpy, then BACT must be applied to all ozone precursors whether or not they individually will exceed 40 tpy.
“There appears to be no dispute between the parties that the Salem facility has the potential to emit two ozone precursors – nitrogen oxide (144 tpy) and VOCs (28 tpy) – at an aggregate level that well exceeds 40 tpy,” the board noted. “However, MassDEP and Footprint argue that BACT requirements do not apply to the Salem project’s VOCs emissions because its VOCs emissions will not exceed the 40 tpy threshold.”
The board directed EPA’s OAR and OGC to submit a supplemental brief that addresses the following question: If a proposed new major stationary source has the potential to emit 40 tpy of either VOCs or nitrogen oxides but not both, what obligation does the permitting authority have, in applying BACT to ozone emissions, to apply BACT to the ozone precursor that does not exceed the 40 tpy standard?
EPA’s OAR and OGC must file their supplemental brief on or before July 25. Petitioners, MassDEP and Footprint may reply to U.S. EPA’s brief, if they choose, by Aug. 1. “Given the need for expeditious disposition of PSD permit appeals, the Board will grant no extensions of time to these deadlines absent a showing of extraordinary circumstances,” the July 14 ruling said.