Fact Sheet - EPA Issues Notice of Data Availability on Proposed Clean Air Mercury Rule
- On Wednesday, December 1, 2004, the Environmental Protection Agency (EPA) published a Notice of Data Availability (NODA) for its proposed Clean Air Mercury Rule.
- The NODA summarizes public comments received during the comment period and solicits further comment on new data and information to help EPA evaluate which regulatory approach will best reduce mercury emissions from power plants.
- The Clean Air Mercury Rule, proposed on January 30, 2004, would reduce
mercury emissions from power plants for the first time ever. EPA proposed two
alternatives for controlling
emissions of mercury from utilities.The
- requiring utilities to install controls known as "maximum achievable control technologies" (MACT) under section 112 of the Clean Air Act. If implemented, this proposal would reduce nationwide emissions of mercury by 14 tons (about 30 percent) by the end of 2007; and
- establishing "standards of performance" limiting mercury emissions from new and existing utilities. This proposal, under section 111 of the Clean Air Act, would create a market based "cap-and-trade" program that would reduce nationwide utility emissions of mercury in two distinct phases. In the first phase, due by 2010, emissions would be reduced by taking advantage of "co-benefit" controls - that is mercury reductions achieved by reducing SO2, and NOx emissions. In 2018, the second phase of the mercury program sets a cap of 15 tons. When fully implemented, mercury emissions would be reduced by 33 tons (nearly 70 percent).
- EPA received over 680,0001 public comments on the rule proposed in January and the related supplemental proposal issued in March.
- Among comments received, there were comments on the Agency's modeling analyses from various groups, including both industry and environmental groups.
- In some cases, EPA and commenters modeled the same or similar policy scenarios, sometimes using the same model, but obtained substantially different results due to differences in the assumptions employed.In these cases, the importance of understanding model input assumptions can be better understood by comparing and contrasting the modeling performed.
- While the public already has access to the comments submitted on the January 2004 proposed rule and the March 2004 supplemental notice, EPA is issuing today's NODA to summarize modeling analyses presented by the commenters and solicit comment on the inputs and assumptions underlying those analyses. In addition, the NODA also summarizes EPA's proposed benefits methodology.
- EPA also received comments concerning the forms or "species" of mercury present in coal-fired power plant emissions. The degree of mercury emissions control depends, in large part, on the form of mercury at issue. The three species of mercury in the emissions gases of coal-fired power plants consist of elemental, ionic or oxidized, and particulate. This NODA seeks additional input on the forms of mercury emitted by coal-fired power plants.
- EPA will take comment on this action for 30 days after publication in the Federal Register. The public comment period will close January 3, 2005.
- The Agency remains committed to issuing the nation's first regulation of mercury from coal-fired power plants by March 15, 2005
For More Information
- EPA will take comment on this action for 30 days after publication in the Federal Register. The public comment period will close January 3, 2005. For more information on the NODA, visit: www.epa.gov/mercury/control_emissions/noda.htm; on the Clean Air Mercury Rule, visit: www.epa.gov/air/mercuryrule/; and on the Clean Air Interstate Rule, visit: www.epa.gov/interstateairquality/.
1As of February 2005, EPA E-Docket shows an actual count of more than 490,000 public comments and close to 4,500 unique comments received. The initial count of 680,000 and 5,000 included duplicate and triplicate e-mails and comments related to other rules.