EPA Developing New Standards to Curb Power Plant Water Pollution


The U.S. Environmental Protection Agency (EPA) recently began finalizing a proposed rule to reduce water pollution from coal-fired power plants and their related wastes. These pollutants include lead, mercury, arsenic, selenium, and other dissolved solids, which are harmful to both human health and aquatic life.

The proposal, which received almost 179,000 public comments, was prompted by a successful 2012 lawsuit by the Sierra Club and Defenders of Wildlife that compelled the EPA to revise its clean water standards for power plants.

A 2009 EPA study found that the current standards, which were last updated in 1982, do not adequately control these pollutants and have not kept pace with changes in the electric power industry over the last three decades. The new proposed rule would reduce pollution by updating technology-based limits and standards that apply to wastewater discharged to surface waters.

Power Plant Water Pollution

Coal-fired power plants are the largest source of toxic water pollution in the United States, dumping billions of pounds of pollution into America’s rivers, lakes, and streams each year. These plants alone contribute 50-60 percent of all the toxic water pollutant discharges from all industries currently regulated by the Clean Water Act, creating a huge toxic burden on the nation’s waters. This is by far the largest source of industrial water pollution in the United States – more than the other top nine polluting industries, including paper mills, refineries, chemical plants, fertil­izer facilities, ore mills and incinerators, combined. The toxic metals in this waste, which are far more hazardous than discharges from public sewage treatment facilities, do not degrade over time and can accumulate in fish.

Tens of thousands of miles of rivers are polluted by these toxic substances. In its 2009 study, EPA identified more than 250 times where coal plants have degraded the quality of ground or surface waters. Since many coal power plants are located on or near lakes, reservoirs, and drinking water supplies, their pollution discharges can affect thousands of miles of waters and millions of people across the country. This pollution raises cancer risks, can inflict lasting brain damage on children, makes fish unsafe to eat, and deteriorates the quality and value of aquatic recreation.

Current storage and treatment practices, such as coal ash settling ponds and chemical precipitation, are not adequately preventing discharges of toxic waste. Coal plants generate wastewater from many of their operations, including water treatment, ash handling, pollutant scrubbing, and yard and floor drainage. Many coal-fired power plants use water to rinse the ash and particulate matter that builds up in their facilities from the combustion process. The resulting mixture of water and ash forms a toxic sludge, which is held and treated in ponds and artificial wetlands. Once the ash has settled out, the toxic water in these sludge ponds can be discharged to surface waters. To make matters worse, many of these ponds are not properly lined and can leach toxic chemicals into groundwater.

Proposed Pollution Control Options

The EPA has proposed eight different levels of pollution controls. The most comprehensive strategy would reduce pollution by an estimated 5 billion pounds a year, while only costing American consumers about $6.46 a year per person. Many of these reductions would be realized through various dry ash handling processes that allow power plant operators to remove toxic byproducts without using water, thus not creating sludge. These methods have the potential to totally eliminate effluent discharges, since the dry byproduct is shipped away in rail cars and buried in properly lined landfills.

The health and environmental benefits from reduced water pollution are estimated at over $600 million, and include:

  • Reductions in human exposure to mercury, arsenic, and lead from fish consumption, which would result in reduced incidences of cancer, reproductive, immunological, neurological, circulatory, and respiratory diseases, and reduced IQ loss in children
  • Reduced impoundment failures, resulting in avoided environmental damages, cleanup costs, property damage, and injuries
  • Reduced groundwater contamination
  • Reduced drinking water treatment costs
  • Fewer deaths from exposure to air pollution due to changes in electricity consumption, transportation, and the fuel used to generate electricity
  • Avoided climate change impacts from reduction in CO2 emissions
  • Improvements in surface water quality, including improved aquatic and wildlife habitats, enhanced water-based recreation (fishing, swimming, and boating), and increased aesthetic benefits
  • Improved protection of threatened and endangered species
  • Increased availability of groundwater resources

In order to maximize the health and safety of our nation’s waters, EPA should not delay in finalizing these long-overdue protections, and it should adopt its most comprehensive discharge standard in the final rule.


EPA Proposed Rule: Steam Electric Power Generating Point Source Category: Effluent Limitations Guidelines and Standards

Sierra Club: Closing the Floodgates- How the Coal Industry is Poisoning Our Water and How We Can Stop It

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