Revised Boiler MACT Rule
EPA is expected to release revisions to its control standards for hazardous air emissions from industrial boilers and process heaters. This rule was adopted in 2011 under requirements of the 1990 amendments to the Clean Air Act. It directs EPA to collect information on the best performing sources in each category and to determine the “maximum achievable control technology” (MACT) for each category’s new and existing sources. It set an aggressive schedule for these new rules, requiring EPA to adopt emissions standards for all of the source categories on the initial list within 10 years.
In March 2011, EPA adopted a MACT standard for new and existing large industrial boilers and process heaters, setting limits on emissions of mercury, dioxin, particulate matter, hydrogen chloride and carbon monoxide, applicable to boilers burning coal, fuel oil, natural gas, or biomass. Across the country, the rule applies to about 14,000 boilers and heaters at refineries, pulp and lumber mills, smelters, chemical manufacturers, auto and machine parts makers, glass makers, and other industrial operations, as well as large institutional facilities, like universities and hospitals. The rule also set limits on mercury and carbon dioxide emissions from smaller boilers, but only if they burn coal. The March 2011 version of Boiler MACT was just the latest attempt by EPA to set standards for emissions of hazardous air pollutants from industrial boilers and process heaters. EPA adopted a MACT standard for this source category in 2004, which was struck down by the courts in 2007.
New Source Performance Standards for Power Plants and Refineries
EPA will also continue to develop two new rules addressing greenhouse gas emissions from power plants and petroleum refineries under the Clean Air Act’s New Source Performance Standards (NSPS) program. Under the NSPS program, EPA is required to establish performance standards for various categories of new and modified stationary sources.
The proposed rule would require coal- and natural gas-fired power plants to emit no more than 1,000 pounds per megawatt-hour of carbon dioxide – a standard that would effectively prohibit the construction of new coat-fired power plants unless they deploy carbon capture and sequestration (CCS) technology.
The Clean Air Act defines a “new source” as a source that has not yet begun construction by the date of a proposed NSPS rule, which in the case of the power plant NSPS is April 13, 2012.
Mercury and Air Toxics Standards for Power Plants
EPA’s Utility MACT standard set aggressive numeric emissions limits for mercury, filterable particulate matter (as a surrogate for toxic metals), and hydrogen chloride (as a surrogate for acid gases). Coal-fired plants subject to the new rules generate about 45 percent of the nation’s electric power, and make up a higher percentage in some regions. The rules also apply to oil-fired plants, which generate about 1 percent of the nation’s electricity. EPA claims the new rules will reduce mercury emissions by 90 percent, acid gas emissions by 88 percent, and cut SO2 another 41 percent beyond reductions expected under the Cross State Air Pollution Rule.
Cross State Air Pollution Rule
EPA’s efforts to regulate the interstate transport of air pollution from power plants also remain in flux. In August 2012, the D.C. Circuit rejected EPA’s Cross State Air Pollution Rule (CSAPR or Transport Rule), which restricted air emissions from power plants in “upwind” states that resulted in air quality exceedances in “downwind” states. See D.C. Circuit Strikes Down EPA Cross-State Air Pollution Rules (Again), Marten Law Environmental News (Sept. 25, 2012). The Transport Rule was drafted to fix deficiencies in a 2005 rule (the Clean Air Interstate Rule or CAIR) that was struck down by the same court in 2008. The court found that the Transport Rule contained flaws similar to those in CAIR – namely, that the rule would, based on cost considerations, require certain upwind states to reduce in-state emissions by more than the amount of their actual contribution to air quality exceedances in downwind states. The court also rejected EPA’s decision to impose federal compliance plans (federal implementation plans or FIPS) on the states without first providing the states with an opportunity to develop state-level compliance plans (state implementation plans or SIPs).
Updating Ambient Standards for Particulates