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What EPA is Doing to Reduce Mercury Pollution, and Exposures to Mercury

Limiting the amount of mercury:

  • Emitted into the air from specific sources
    • In 2011, EPA issued the Mercury and Air Toxics Standards (MATS) regulation to reduce emissions of toxic air pollutants from coal- and oil-fired power plants. The compliance date for MATS was in 2015, and power plants have taken steps such as installing controls or updating operations to meet these standards, which protect public health. The standards also provide considerable health benefits. MATS was estimated to prevent up to 11,000 premature deaths, 4,700 heart attacks and 130,000 asthma attacks every year beginning in 2016.

    • EPA issued final standards for mercury from chlor-alkali production, a technology used to produce chlorine, in 2003. EPA estimates that mercury emissions from chor-alkali plants have been reduced by approximately 88 percent from the pre-2003 levels; this estimate includes reductions resulting from plant closures. In 2008 and 2011, EPA proposed amendments to these final standards.

    • EPA issued final regulations for large municipal waste combustors (MWCs) in 1995 and for small MWCs in 2000. Implementation of large MWC regulations has reduced mercury emissions by 88 percent from 1990 emission levels. Large municipal waste combustors are incinerators which are capable of burning greater than 250 tons of municipal waste per day and which burn household, commercial, and/or institutional waste. Burning waste reduces its volume before disposal into a landfill. Municipal waste combustors include the subcategory of waste-to-energy plants which generate electricity or steam from burning waste. Small municipal waste combustors serve smaller communities and burn 35 to 250 tons of waste per day.

    • In the past mercury was used in many paints as a fungicide to prevent the growth of bacteria. To be used as a fungicide, it had to be registered with EPA's pesticides program. In 1990, EPA cancelled this registration, in effect banning its use in paint.

  • Discharged into water from specific sources

    EPA issues effluent guidelines, which are national regulatory standards for wastewater discharged to surface waters and municipal sewage treatment plants. EPA issues these regulations for industrial categories, based on the performance of treatment and control technologies.

    Dental effluent guidelines. EPA has issued final pretreatment standards to reduce discharges of mercury from dental offices into municipal wastewater treatment plants. The final rule requires dental offices that place or remove amalgam fillings to install amalgam separators that remove and collect the amalgam so that the mercury in it can be easily recycled. EPA expects compliance with this final rule will annually reduce the discharge of mercury by 5.1 tons.

    Effluent guidelines for steam electric utilities. In September 2015, EPA finalized a rule revising the regulations for steam electric plants. Steam electric plants use nuclear or fossil fuels (such as coal, oil and natural gas) to heat water in boilers, which generates steam. The steam is used to drive turbines connected to electric generators. The plants generate wastewater in the form of chemical pollutants and thermal pollution (heated water) from their water treatment, power cycle, ash handling and air pollution control systems, as well as from coal piles, yard and floor drainage, and other miscellaneous wastes.

    The rule sets the first federal limits on the levels of toxic metals in wastewater that can be discharged from these plants, based on technology improvements in the steam electric power industry over the last three decades.

  • In your drinking water

    Under the Safe Drinking Water Act, EPA in 1991 set an enforceable regulation for inorganic mercury, called a maximum contaminant level (MCL), at 0.002 mg/L or 2 ppb. Public water systems must ensure that your drinking water does not exceed the MCL for mercury. MCLs are set as close to the health goals as possible, considering cost, benefits and the ability of public water systems to detect and remove contaminants using suitable treatment technologies. EPA periodically reviews this standard to ensure that the MCL continues to be protective of human health.

  • Disposed of in landfills and surface impoundments

    Coal combustion residuals, commonly known as coal ash, are created when coal is burned by power plants to produce electricity. Coal ash contains contaminants like mercury, cadmium and arsenic. EPA has developed regulations on the safe disposal of coal ash in landfills and surface impoundments.