Monday, September 21, 2009

EPA to Rewrite Rules for Watery Discharges from Coal Plants

WASHINGTON, DC, September 17, 2009 (ENS) - The U.S. Environmental Protection Agency plans to revise the existing standards for water discharges from coal-fired power plants to reduce pollution and better protect America's surface water, the agency said Tuesday.

Wastewater discharged from coal ash ponds, air pollution control equipment, and other equipment at power plants can contaminate drinking water sources, cause fish and other wildlife to die and create other detrimental environmental effects, the EPA says.

Earlier this year, EPA completed a multi-year study of power plant wastewater discharges.

As part of the study, EPA personnel conducted a sampling program to characterize raw wastewaters generated by coal-fired power plants, as well as evaluate treatment technologies and best management practices used to reduce pollutant discharges.

The Engineering and Analysis Division of the EPA Office of Water, which conducted the study, concluded that current regulations, which were issued in 1982, have not kept pace with changes that have occurred in the electric power industry over the last three decades.

Based on information in the report, the agency determined that revising the current effluent guidelines for the industry is warranted.

EPA's decision to revise the current effluent guidelines is "driven by the high level of toxic-weighted pollutant discharges from coal fired power plants and the expectation that these discharges will increase significantly in the next few years as new air pollution controls are installed," the agency said in a statement.

Air pollution controls installed to remove pollution from smokestacks have made great strides in cleaning the air people breathe, saving lives and reducing respiratory and other illnesses.

But some of the equipment used to clean air emissions does so by "scrubbing" the boiler exhaust with water, and when the water is not properly managed it sends the pollution to rivers and other waterbodies.

Treatment technologies are available to remove these pollutants before they are discharged to waterways, but these systems have been installed at few of the power plants.

As part of the multi-year study, EPA measured the pollutants present in the wastewater and reviewed treatment technologies, focusing mostly on coal-fired power plants.

Many of the toxic pollutants discharged from these power plants come from coal ash ponds and the flue gas desulfurization systems used to scrub sulfur dioxide from air emissions.

Other sources of polluted discharge are coal pile runoff, metal and chemical cleaning wastes, and coal washing, the study shows.

"The rainfall generating the coal pile runoff can dissolve inorganic salts or cause chemical reactions in the coal piles, which will be carried away in the runoff. Coal pile runoff may contain high concentrations of copper, iron, aluminum, nickel, and other constituents present in coal," the study states.

Plants typically direct coal pile runoff wastewaters to a holding pond along with stormwater runoff from other areas near the coal pile.

During EPA's site visits and sampling program, personnel determined that many of the plants operating segregated coal pile runoff ponds collect and store the runoff in ponds until the pond is at a level that could overflow. At that point, the plant either discharges the coal pile runoff to surface waters or commingles the coal pile runoff with other wastewater prior to discharge.

These are some of the discharges that the agency intends to cover with new regulations. Once the new rule for electric power plants is finalized, EPA and states would incorporate the new standards into wastewater discharge permits.

EPA's Office of Water is coordinating its efforts for the study with ongoing research and activities being undertaken by other EPA offices, including the Office of Research and Development, the Office of Solid Waste, and the Office of Air and Radiation's Office of Air Quality Planning and Standards and the Office of Atmospheric Programs.

EPA is also coordinating some of its activities with the Utility Water Act Group, an industry trade association, and has held technical information discussions with the Electric Power Research Institute and treatment equipment vendors.

More information about EPA's study is provided in an interim report published in August 2008. Click here to view the interim report. A final study will be published later this year.



http://www.ens-newswire.com/ens/sep2009/2009-09-17-091.asp

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