Notice

On December 24, 2009, EPA

approved an Information

Collection Request requiring

power plants to submit

emissions information for use

in developing air toxics

emissions standards. Learn

more

You are here: EPA Home Air and Radiation Clean Air Mercury Rule Basic Information

Basic Information

Mercury and Fish

Revision of December 2000 Finding

Cap and Trade Basics

For More Information

EPA Press Release

On March 15, 2005, EPA issued a rule to permanently cap and reduce mercury emissions from

coal- fired power plants.

The Clean Air Mercury Rule was built on EPA’s Clean Air Interstate Rule (CAIR) to

significantly reduce emissions from coal- fired power plants -- the largest remaining

sources of mercury emissions in the country. The goal of these rules regarding mercury

was to reduce utility emissions of mercury from 48 tons a year to 15 tons, a reduction

of nearly 70 percent.

The Clean Air Mercury Rule establishes “standards of performance” limiting mercury

emissions from new and existing coal-fired power plants and creates a market-based

cap-and-trade program to reduce nationwide utility emissions of mercury in two

distinct phases. The first phase cap is 38 tons. In the second phase, due in 2018,

coal- fired power plants will be subjec t to a second cap, which will reduce emissions to

15 tons upon full implementation.

New coal- fired power plants (“new” means construction starting on or after Jan. 30,

2004) will have to meet stringent new source performance standards in addition to

being subjec t to the caps.

Mercury is a toxic, persistent pollutant that accumulates in the food chain. Mercury in

the air is a global problem. While fossil fuel-fired power plants are the largest remaining

source of human-generated mercury emissions in the United States.

The Clean Air Mercury Rule is expected to make reductions in emissions that are

transported regionally and deposited domestically, and it will reduce emissions that

contribute to atmospheric mercury worldwide.

Mercury and Fish

Concentrations of mercury in the air are usually low. However, atmospheric mercury

falls to Earth through rain, snow and dry deposition and enters lakes, rivers and

estuaries. Once there, it can transform into, methylmercury, and can build up in fish

tissue.

Americans are exposed to methylmercury primarily by eating contaminated fish.

Because the developing fetus is the most sensitive to the toxic effects of

methylmercury, women of childbearing age are regarded as the population of greatest

concern. Children who are exposed to methylmercury before birth may be at increased

risk of poor performance on neurobehavioral tasks, such as those measuring attention,

fine motor func tion, language skills, visual-spatial abilities and verbal memory.

Revison of December 2000 Finding

Also on March 15, 2005, in a separate but related action, EPA revised and reversed its

December 2000 finding that it was “appropriate and necessary” to regulate coal- and

Clean Air Mercury Rule

http://www.epa.gov/camr/basic.htm

Last updated on Wednesday, January 20, 2010

3/15/2011 Basic Information | Clean Air Mercury ...

http://www.epa.gov/camr/basic.htm 1/2
oil-fired coal- fired power plants under section 112 of the Clean Air Act.

EPA has issued two complementary rules – CAIR and the Clean Air Mercury Rule, issued

under sec tions 110(a)(2)(D) and 111 of the law, respectively. These rules will allow us

to limit mercury emissions from these plants.

Cap and Trade Basics

The Clean Air Mercury Rule established a cap-and-trade system for mercury that is

based on EPA’s proven Acid Rain Program. The Acid Rain Program has produced

demonstrable results, reducing SO2 emissions faster and at far lower costs than

anticipated, and resulting in wide-ranging environmental improvements.

In the Clean Air Mercury Rule, EPA has assigned each state and two tribes an emissions

“budget” for mercury, and each state must submit a State Plan revision detailing how it

will meet its budget for reducing mercury from coal- fired power plants. Two tribes that

have coal- fired power plants that will be affected by this rule also have been assigned

a mercury emissions budget.

The Clean Air Mercury Rule contained stringent emission monitoring and reporting

requirements ensure that monitored data are accurate, that reporting is consistent

among sources – and that the emission reduc tions occur.

For More Information

More information about mercury, EPA’s efforts to reduce mercury emissions, and

today’s rule is available at www.epa.gov/mercury.

More information about EPA/FDA’s fish advisory go to Web site

www.c fsan.fda.gov/~frf/sea-mehg.html

3/15/2011 Basic Information | Clean Air Mercury ...

http://www.epa.gov/camr/basic.htm 2/2