On December 31, 2011 MassDEP issued its Final Regional Haze State Implementation Plan (SIP). The SIP, required under Section 169A of the federal Clean Air Act, includes measures for improving visibility conditions in certain national parks and wilderness areas that are designated as Class I areas. Regional haze is caused by fine particles, including aerosols that impair visibility over a large region by scattering or absorbing light. Although Massachusetts has no Class I areas, emissions from Massachusetts sources contribute to visibility degradation in Class I areas in several other states. These include Lye Brook Wilderness Area (Vermont), Great Gulf Wilderness Area (New Hampshire), Presidential Range-Dry River Wilderness Area (New Hampshire), Acadia National Park (Maine), Moosehorn Wildlife Refuge (Maine), and Roosevelt Campobello International Park (Maine/Canada). The regulatory procedure for installing pollution control or other means for reducing emissions of particles and aerosols is referred to as Best Available Retrofit Technology (BART).
In the SIP, Massachusetts agreed to reduce SO2 emissions from five specific power plants that were determined to contribute significantly to regional haze. SO2 emissions from these power plants are to be reduced by 90 percent from 2002 levels by 2018, or to pursue equivalent, alternative measures. These power plants have already reduced SO2 emissions due to Massachusetts air quality regulations.
Massachusetts also identified one municipal waste combustor and one industrial boiler whose emissions were determined to contribute significantly to regional haze. For the municipal waste combustor, Massachusetts has made a source-specific BART determination and will finalize a permit with that determination in early 2012. For the industrial boiler, no BART determination was needed since the facility accepted an emissions cap that sufficient reduced its emissions.
The regional haze studies completed to prepare the SIP concluded that significant broad-based reductions in SO2 emissions could be achieved by requiring lower sulfur content fuel oils, including #2 distillate oil (home heating oil) and #4 and #6 residual oils (used in power plants and industrial and commercial boilers). MassDEP intends to implement a low sulfur fuel oil strategy by proposing regulations in early 2012 to lower allowable sulfur content in fuel oils, ultimately achieving 15 parts per million sulfur for #2 oil and 0.5 percent sulfur by weight for #4 and #6 residual oils by 2018.
If you have questions about the MassDEP’s Final Regional Haze SIP, please contact Trinity’s Massachusetts office at (508) 630-2246.