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Mercury Policy (9-14-05)

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Concern over the possible health effects of mercury contamination is getting increased attention nationwide. Humans are exposed to mercury primarily through consumption of fish that contain high levels of mercury from deposition of atmospheric mercury released by power plants. In 2001, 49 states issued 2,618 fish advisories due to high mercury concentrations. There are currently no regulations to control mercury emissions specifically from power plants, but efforts are underway. The Environmental Protection Agency (EPA) is expected to propose rules it has been developing since 2000. Also, the president's Clear Skies Initiative and congressional efforts to amend the Clean Air Act might reduce mercury emissions from power plants before the EPA's rules are implemented.

Recent Action

On Tuesday, September 13, 2005, the Senate narrowly rejected a resolution introduced by Senator Patrick Leahy (D-VT) asking the U.S. E.PA. to rewrite a rule change on mercury emissions from coal-fired power plants. The new mercury rule, which was finalized last March, removes mercury emissions from power plants from the Clean Air Act list of hazardous pollutant sources and establishes a cap and trade program for mercury emissions. Senator Leahy and 34 co-sponsors claimed that the rule would delay reductions in emissions and could cause serious health problems, especially for pregnant women and young children living near power plants.

If the resolution had passed, it would have forced the EPA to rewrite the rule under the 1995 Congressional Review Act, which gives lawmakers a guaranteed floor vote for resolutions that challenge federal agency regulations. (9/12/05)

Previous Action

On March 15, 2005 the EPA acting Administrator Stephen Johnson signed the Clean Air Mercury Rule, which aims to cut mercury emissions at U.S. coal-fired power plants in two phases using a cap-and-trade scheme. The first phase of caps would reduce nation-wide annual emissions from 48 tons to 38 tons by 2010, and reach these goals as a collateral beneift of the recently finalized Clean Air Interstate Rule (CAIR), which will regulate nitrous oxides and sulfur dioxide in eastern U.S. plants. The second phase of limits would reduce national emissions to 15 tons per year by 2018, a 70% reduction in total. Some lawmakers, state officials, and environmentalists are outraged over the rule and have pledged to block it from taking effect. Allowing utilities to trade a neurotoxin "is unprecedented and illegal," says Bill Becker, Executive Director of the State and Territorial Air Pollution Program Administrators. Environmentalists predict that the trading of mercury credits will leave many plants unregulated, sacrificing the health risks of certain local communities to the benefit of industry interests. According to a Greenwire report, the National Resources Defense Council also pointed out that EPA's own modelling shows that mercury emissions won't reach the promised 2018 targets until 2026. According to Greenwire, several environmental groups and a coalition of state officials are poised to file law suits on the grounds that the rule violates an earlier EPA determination, which classified mercury as a "hazardous air pollutant" that must be regulated at each of the country's 1,300 plants. To avoid conflict, the Administration officially overturned this determination, but groups maintain there is little basis for that decision.

EPA Assistant Administrator Jeffrey Holmstead rebutted wide-spread skepticism about the rule, insisting that the trading program would eliminate local mercury "hot spots" because it is designed to incentivize bigger power plants to overcomply early and sell credits, according to an in-depth report in Electric Utility Week. Industry favors the cap-and-trade approach, because it offers utilities the regulatory certainty they need to control emissions at a reasonable expense and without litigation delays. But environmental groups point to two accountability studies by the EPA Inspector General and the Government Accountability Office, that suggest EPA rulemakers insufficiently considered public health risks. Concerned about these shortcomings, certain members of both the House and Senate have expressed their disappointment with the ruling and continue to devise plans to thwart it. (3/21/05)

On February 16, 2005 a new report released by House Resources Committee Chairman Richard W. Pombo (R-CA) and Energy and Mineral Resources Subcommittee Chairman Jim Gibbons (R-NV) challenged the basis for concerns over fish consumption and mercury sourced from U.S. coal-fired power plants. Entitled Mercury in Perspective: Fact and Fiction About the Debate Over Mercury, the paper outlines federally and privately sponsored research, highlighting their findings that U.S. power plants account for less than 1% of global mercury emissions, and that no direct connection has been proven between U.S. power plant emissions and mercury accumulation in fish. The report primarily aims to correct the public perception that mercury is an increasing threat, emphasizing that mercury emissions in the U.S. have declined since 1990 due to strict regulations of waste combusters and mining operations, deeming controls on coal-fired power plants less necessary. Featuring studies that downplay the threat of fish consumption to public health, the report recommends a revision of the EPA mercury Reference Dose, and endorses the phased cap-and-trade approach as proposed in the Clear Skies bill.

The report comes two weeks before a scheduled mark-up of Clear-Skies and an EPA rulemaking scheduled for March 15th. It also follows on the heals of an EPA Inspector General report released February 3, 2005 which claimed that the proposed EPA rule, which includes a cap-and-trade option, was unduly influenced by the Administration's political goals and violated the Clean Air Act. (2/24/05)

In response to members of the Senate Environment and Public Works Committee, the U.S. Enviornmental Protection Agency (EPA) Inspector General issued a 54-page report on February 3, 2005. The Senators had asked the Inspector General to investigate the rule-making process for mercury pollution limits under development by the EPA. There is concern about whether the 2 different approaches, a cap-and-trade program (proposed in the Clear Skies legislation) or a maximum achievable control technology (MACT; described in the Clean Air Act), were being adequately and fairly considered to develop these rules.

The Inspector General concluded that EPA is developing regulations that would require a 34 ton annual limit on mercury based on a cap-and-trade program that might also leave some regional hot spots of higher levels of mercury. In addition, EPA has not conducted a complete analysis of the cost-effectiveness of the alternative MACT approach and thus has not fairly considered all of their options. The proposed rule violates the Clean Air Act which mandates that toxic levels be reduced to the level that the top 12% of current high-performance units can achieve. The EPA has also not considered the effects of the proposed new rules on the health of children.

The Inspector General summarized their report in a press statement: "While we are not advocating one regulatory approach over another, we recommend that EPA conduct sufficient analysis to better ensure that the approach it chooses would accomplish the lowest achievable emissions levels in the shortest time possible."

These problems with the EPA rule-making process could lead to further litigation by environmental groups, who have already voiced objections. According to Greenwire, John Walke of the Natural Resources Defense Council called the report a stinging indictment of the administration's effort to advance a biased mercury plan. "This report absolutely bolsters our case," said Walke in an interview with Greenwire. "It shows how politicized and arbitrary the rule development process was, which is precisely the type of facts that lead courts to strike down agency action."

The EPA rules must be finalized by March 15, 2005 and must abide by the Clean Air Act unless any version of the Clear Skies Initiative is passed by Congress before that date. For more information on actions and hearings in January 2005 related to the Clear Skies Initiative in the Senate please see and (2/8/05)


As the number of states with fish advisories continues to climb, an improved understanding of the biogeochemical cycle of mercury through atmospheric, aquatic, and biological systems becomes ever more critical in crafting policy affecting water and air quality. Mercury is naturally released into the biosphere through volcanoes, geothermal springs, geologic deposits, and oceans. Anthropogenic sources, which include waste incinerators, wastewater discharges, mining, and power plants (most significantly coal-fired power plants), have nearly doubled the natural amount of atmospheric mercury since the beginning of the industrial age.

After being released into the environment, mercury does not usually remain confined around single point sources. Instead the majority of mercury is released into the air (usually in elemental form) and then dispersed on local, regional, and global scales before being deposited. It is estimated that 40% of mercury deposited in the US originated outside of the country. After deposition, sulfur-reducing bacteria transform mercury into the organic methylmercury through a process called methylation. The amount of mercury transformed to methylmercury, and vise versa, depends on several factors including the concentration of dissolved organic carbon and pH.

Methylmercury is the most toxic form of mercury. It both bioaccumulates (absorbed more quickly than eliminated) and biomagnifies (concentration increases up the food chain). Methylmercury can cause brain damage, nervous disorders, tremors, vision, and memory loss. Some evidence also links methylmercury to cardiovascular, thyroid, and digestive problems. Methylmercury is most commonly ingested by humans through fish consumption. Inorganic mercury is less efficiently absorbed by the body than methylmercury, and thus does not tend to cause serious health problems.

Mercury emissions from municipal waste combustors, medical waste incinerators, and hazardous waste combustors are currently regulated, but other large sources are currently not controlled. In adhering to the Clean Air Act's requirement to assess toxic emissions from power plants, the Environmental Protection Agency (EPA) released two reports in 1997 and 1998 that specifically identified mercury as the toxic posing the greatest concern to public health. The reports also determined that coal-fired power plants released the greatest quantities of mercury, oil-fired plants released enough to require regulations, and natural gas-fired plants release negligible amounts. In December 2004, the EPA finalized rules to reduce mercury emissions from coal-fired power plants to be implemented by December 15, 2007.

In February 2003, mercury contamination re-emerged as an issue on Capitol Hill after the release of two reports indicating mercury levels are higher -- and the resulting health effects more severe -- than previously thought. The first report, America's Children and the Environment released by the EPA, found that 1 in 12 women in the U.S. had mercury levels at the upper limit of what is considered safe, placing 300,000 children at risk for brain damage. Another report by the United Nations Environmental Program called for significant and rapid cuts to global mercury emissions after finding that coal-fired power plants in Asia and Africa especially account for nearly 70% of all atmospheric mercury, deposited globally.

In December, 2003 the EPA proposed a new cap-and-trade rule to curb mercury emissions, a policy that reflected the Bush Administration's preference of market based approaches to environmental regulation. It soon came under fire as insufficient to lower atmospheric mercury levels. In contrast to across-the-board restrictions on individual power plants ("Maximum Achievable Control Technology" or MACT), the alternative policy, the ability to trade pollution "credits" would create highly toxic localized environments. On several separate occasions in January, April and June of 2004, members of congress from both parties as well as state governments petitioned or filed complaints against the EPA and the Bush Administration, asking them to reconsider the new mercury rule. Many opponents argued the rule violated the Clean Air Act, while others voiced concern that industry interests were too prioritized or propsed a regional, rather than national, cap-and-trade scheme. Read more about Clear Skies:

On August, 2004, EPA officials released a major announcement that mercury contamination in the nation's waters have reached an all-time high. EPA Administrator Mike Leavitt attributed these statistics to the rise in assessment of the nation's waters through monitoring and fish sampling. He also stated that manmade mercury emissions are decreasing, with power plant emissions dropping 45 percent between 1990 and 1999. Rising levels, he explained, are partly due to pollution from other countries, specifically Asia, which accounted for 53 percent of global mercury emissions in 1995.

Sources: Atlanta Journal-Constitution, Congressional briefings, EPA, Food and Drug Administration, Greenwire, USGS, Water Environmental Federation, House Science Committee website, Environment and Energy Daily, The Washington Post, Los Angeles Times, Platts Electric Utility Week, and hearing testimony.

Contributed by Katie Ackerly, AGI/AAPG 2005 Spring Semester Intern; Emily Lehr Wallace, AGI Government Affairs Program Staff; Linda Rowan, AGI Director of Government Affairs

Please send any comments or requests for information to AGI Government Affairs Program.

Last updated on September 14, 2005

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