The U.S. Environmental Protection Agency said in an April 24 Federal Register notice that it has approved a revision to the Maine State Implementation Plan (SIP) that addresses regional haze for the first planning period from 2008 through 2018.
This revision was submitted by the Maine Department of Environmental Protection (Maine DEP) in December 2010, with supplemental submittals in September 2011 and November 2011. This revision addresses the requirements of the Clean Air Act (CAA) and EPA’s rules that require states to prevent any future, and remedy any existing, manmade impairment of visibility in mandatory Class I Areas. This approved rule is effective on May 24.
In November 2011, EPA published a Notice of Proposed Rulemaking (NPR) that proposed approval of the Maine SIP. EPA also proposed to approve Maine’s Best Achievable Retrofit Technology (BART) determinations for several sources and to incorporate the license conditions that implement those determinations into the SIP. In addition, EPA proposed to approve Maine’s low-sulfur fuel oil legislation and to incorporate this legislation into the Maine SIP. EPA also proposed to approve a Maine state regulation, Control of Emissions from Outdoor Wood Boilers.
EPA said it received a number of comments on that November 2011 proposal to approve Maine’s Regional Haze SIP submittal. Comments were received from the citizen’s group Credo Action and the National Park Service (NPS). A joint letter from the National Parks Conservation Association (NPCA), the Appalachian Mountain Club (AMC), the Conservation Law Foundation (CLF), and the Natural Resources Council of Maine (collectively NPCA) was also submitted.
Paper mill decisions come in for critical comments
Many of the NPCA comments echoed comments submitted by NPS. NPCA commented that in light of the $/ton limits accepted by other states (e.g., $7,300/ton in Oregon, $5,000/ton in Colorado, and $7,000–$10,000/ton in Wisconsin), Maine lacks a state cost effectiveness threshold in its Best Available Retrofit Technology (BART) determinations. EPA said that while states have the option to develop a cost effectiveness threshold, the regional haze rule does not require states to set a bright line threshold for cost effectiveness. Even though the cited states adopted a dollar per ton threshold, controls with costs below the established cost threshold were sometimes rejected when considered in conjunction with the other factors, EPA noted.
NPS commented that the analysis of lower sulfur fuel oil for Verso Androscoggin Power Boilers 1 and 2 is incomplete, inaccurate, and does not follow BART Guidelines or the MANE–VU recommendations. NPS suggested that EPA should at least evaluate the lower sulfur residual oils for the Verso Androscoggin boilers. Verso Androscoggin is a pulp and paper plant and Maine’s analysis is therefore not required to follow the BART Guidelines, EPA responded. The MANE–VU recommended level of control for industrial boilers is the use of 0.5% sulfur in fuel #6 oil. Maine’s BART limit for Verso Androscoggin Power Boilers 1 and 2 requires the reduction from 1.8% sulfur in fuel oil to the use of 0.7% sulfur in fuel oil by Jan. 1, 2013. The source will, however, be subject to the MANE–VU recommended 0.5% sulfur in fuel limit by no later than Jan. 1, 2018, pursuant to Maine’s low sulfur fuel oil legislation.
NPS commented that in its analysis of the switching to natural gas, Verso Androscoggin assumed $9.43 per thousand cubic feet (MCF) which is more than double the current price. NPS claimed that EPA must reevaluate the costs of switching to natural gas using current cost information. EPA responded that the Verso Androscoggin analysis of switching to natural gas assumed $9.43/MCF based on 2009 data. The most recent data from the U.S. Energy Information Administration indicates an increase in the 2010 annual industrial price of natural gas to $11.23/MCF and monthly industrial prices are in the range of $8.61 to $12.08/MCF for the second half of 2011. Therefore, the use of $9.43/MCF is acceptable, EPA ruled.
NPS also commented that Maine DEP improperly dismissed application of FGR (Flue Gas Recirculation) at Verso Androscoggin from further evaluation on the premise that it would result in minimal reductions in NOX emissions. EPA said the state of Maine has flexibility as to how the factors of the BART analysis are weighed and is not required to conduct an analysis that conforms to the requirements of BART Guidelines because Verso Androscoggin is not a 750-MW power plant.
EPA says state fuel oil sulfur cuts enough for Wyman plant
NPS said in another comment that it determined that lower sulfur (0.5% and 0.3%) fuels at Wyman Station Units #3 and #4 would improve cumulative visibility. NPS claimed that because neither Maine DEP nor EPA had presented any benchmark against which to compare its haze reduction analysis estimates, EPA must agree that BART for Wyman boilers #3 and #4 is the use of 0.3% sulfur residual oil. EPA said the Maine BART limit for Wyman requires the reduction from 2.0% sulfur in fuel oil in boiler #3 to the use of 0.7% sulfur in fuel oil and the continued use of 0.7% sulfur in fuel in boiler #4 by Jan. 1, 2013. In addition, as part of Maine’s long term strategy, both boilers, along with the two other boilers on site, will be required to meet a further reduction to a 0.5% sulfur limit by Jan. 1, 2018.
FPL Energy Wyman is an 850-MW power plant located on Cousins Island in Yarmouth, Maine. The plant consists of four generation units, all of which fire #6 residual fuel oil. A fifth unit is a smaller oil-fired auxiliary boiler and a sixth unit is an emergency backup diesel generator that provides electricity for use on-site. Boiler #3 is a Combustion Engineering boiler, installed in 1963, with a maximum design heat input capacity of 1,190 MMBtu/hr firing #6 fuel oil (with 2.0% sulfur content by weight). Boiler #4 is a Foster Wheeler boiler, installed in 1975, with a maximum design heat input capacity of 6,290 MMBtu/hr firing #2 or #6 fuel oil (with 0.7% sulfur).
The Maine DEP decided that existing particulate and NOx controls for Wyman #3 and #4 are enough, and that the future SO2 reductions under the Maine fuel oil rule would meet regional haze needs.