Managing Mercury in Air

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New York's Adopted Mercury Utility Rule: 6 NYCRR Part 246, Mercury Reduction Program for Coal-Fired Electric Utility Steam Generating Units Express Terms Summary:
The Department adopted a mercury regulation which incorporates the Phase I emission cap established in the federal Clean Air Mercury Rule (CAMR) for the years 2010-2014, and beginning in 2015, establishes a facility-wide emission limit for each applicable facility. Phase I of the State regulation, 6 NYCRR Part 246, imposes an annual facility-wide mercury emission limitation, based upon the state mercury budget distributed to New York State by EPA. Applicable facilities will not be permitted to generate and trade mercury reductions with other facilities or other States. The annual facility-wide emission limitation will be in effect from 2010 to 2014. Starting in 2015, Phase II, in conjunction with other electric sector regulations such as the Regional Greenhouse Gas Initiative (RGGI) and the second phase of the Clean Air Interstate Rule (CAIR), the State mercury regulation will establish a facility-wide emission limit for each applicable facility. The Department will submit Part 246 to EPA for approval in lieu of New York State accepting the model rule requirements in CAMR.
EPA's Clean Air Mercury Rule Fact Sheet:
This rule established a cap-and-trade system for mercury emissions from Electric Utility Steam Generating Units, based on EPA's Acid Rain Program, rather than establishing traditional Section 112(d) MACT standards based on technology performance.
Portland Cement Plant Mercury Emissions Exempted - 2/20/07: New York State Attorney General Andrew M. Cuomo today (www.oag.state.ny.us/press/2007/feb/feb20a_07.html) announced a multi-state (CT, DE, IL, MD, MA, MI, NJ, PA) legal challenge to the federal government for adopting a rule that refuses to regulate mercury and other pollutants from existing Portland Cement Plants. The states seek to have a federal court overturn the rule by finding that the agency's rule violates the Clean Air Act. A petition, signed by nine states, was filed today in the U.S. Court of Appeals for the District of Columbia Circuit. Portland cement is the primary cement used in building projects and road construction; it is produced throughout the United States.

Mercury Management in New York State

The Mercury Cycle.
(click on image to see a larger view)

Human-caused (anthropogenic) emissions (past and present) have resulted in increased concentrations of mercury in the environment. Approximately 158 tons of mercury are emitted from U.S. manmade sources every year. Over 85% of these emissions are from combustion sources, including fossil fuel and waste combustion. The global input to the atmosphere of all sources of mercury (including natural, oceanic and manmade) is estimated to be 5,500 tons. Rates of mercury deposition are increased in the Northeast relative to other parts of the country due to prevailing west to east wind patterns and mercury emissions within the region.

The majority of mercury in the atmosphere is in the form of gaseous elemental mercury, Hg(0). This form of mercury can travel long distances in the atmosphere for many months.

Some Hg(0) is converted into 2 other forms of mercury:

a more water soluble form of mercury, divalent or oxidized mercury, Hg (II)
it can bind with particulate matter or aerosols to form particulate mercury, Hg(p)

These two forms of mercury are rapidly removed form the atmosphere in precipitation and fall onto land and into waterbodies, including the ocean.

In a waterbody and in the sediments of the waterbody mercury may be converted by bacterial action into an organic form, methylmercury, CH₃Hg. Acidic conditions and elevated ozone levels are believed to promote this conversion. Methylmercury can bioaccumulate up the food chain as a result of the ingestion of the contaminated aquatic organisms. Large fish and aquatic mammals at the top of the food chain may contain dangerously high levels of methylmercury. Contaminated fish become a human health hazard when they are consumed.

Methylmercury is slowly eliminated from the body. Animal studies and accidental poisonings have demonstrated that the embryo/fetus and young children are more sensitive to mercury than the adult. Methylmercury can travel across the placenta and accumulate in the fetal brain. It can also be found in breast milk. In the embryo/fetus and young children methylmercury has been shown to inhibit the normal development of the nervous system and produce generalized lesions throughout the brain. Lower levels of exposure may not be apparent until later when the child's motor and verbal skills may be delayed or abnormal. Pregnant women may not show any effects but their unborn children may be adversely effected. EPA has estimated that 8% of women of childbearing age in the general U.S. population have blood levels of mercury higher than the EPA's reference level for mercury.

In adults, methylmercury concentrates in the kidneys, liver and brain. Nephritis, as well as neurological and cardiovascular effects, may result in adults. In conclusion, neurodevelopmental deficits are the most sensitive and well-documented health effects.

By reducing mercury emissions to the atmosphere from anthropogenic (manmade) combustion sources we hope to reduce the level of mercury in fish flesh and decrease the subsequent threat to the health of humans and wildlife.

Effective October 30, 2002: 6 NYCRR Subpart 219-1, Incineration-General Provisions, Subpart 219-2, Municipal and Private Solid Waste Incineration Facilities, and new Subpart 219-7, Mercury Emission Limitations for Large Municipal Waste Combustors that are Constructed on or before September 20, 1994, pursuant to Environmental Conservation Law (ECL) Sections 1-0101, 3-0301, 19-0103, 19-0105, 19-0301, 19-0303, 19-0305, and 19-0306. Promulgation of this rule lowered the mercury emission limit for large municipal waste combustor plants from 80 ug/dscm or 85% removal, whichever is less stringent, to 28 ug/dscm or 85% removal, whichever is less stringent. This regulation will reduce mercury emissions and subsequent environmental loading of mercury in New York and the Northeast.