Toxic selenium in Kentucky streams
Unprecedented levels of toxic selenium are being dumped in Kentucky streams with the knowledge and consent of the Beshear administration.
Elevated levels of selenium are found in streams below coal mines in eastern Kentucky, with state officials taking action to shield coal companies from the liability that comes with exposing the public to dangerous levels of this pollutant.
In fact, in 2009 the Division of Water withheld held data that showed how problematic selenium pollution is becoming. It denied Open Record Requests so that it could issue the General Permit for Coal Mining without requiring a water quality limit for selenium.
That data, collected in a 2007 survey of 13 sites in eastern Kentucky, showed that water downstream exceeded state water quality standards at one mining site and one road cut. Streams below other mining sites showed elevated levels. Below three mining sites, fish tissue levels exceeded U.S. Environmental Protection Agency's recommendations. In five other areas, the levels in fish were high enough to be harmful.
Elevated selenium levels are now showing up in other water monitoring tests in eastern Kentucky streams. High selenium levels are also found where there is coal ash pollution.
More about selenium
Selenium is a mineral that occurs naturally and is necessary for life in small amounts; however, it can be toxic to aquatic life at very low levels. Selenium can also be harmful to human health. Short-term exposure can cause hair and fingernail loss, and irritability. Long-term exposure can damage the liver, kidneys, nervous system, and circulatory system.
Selenium contaminates streams when coal seams and associated rock layers containing selenium are exposed through surface coal mining. Once in the ecosystem, selenium bioaccumulates in fish, birds, and other aquatic organisms, building up to toxic levels in the animals’ tissues. Humans can be exposed to selenium through drinking water and eating contaminated fish.
What Levels are Toxic?
Studies have found toxic effects of selenium on fish at levels as low as 2 - 5 μg/L (micrograms per liter) in water, and 3 ppm (parts per million) in fish tissues (Lemly). The EPA has already established a chronic standard for selenium in freshwater of 5 μg/L.
Despite extensive scientific evidence that selenium is toxic to aquatic life at very low levels, Kentucky officials are proposing to weaken standards for selenium pollution to 258 ppm in water for acute exposure and 8.6 ppm in fish tissue for chronic exposure.
Sources and other studies
- Lemly, A. Dennis. Aquatic Hazard of Selenium Pollution From Mountaintop Removal Coal Mining. 2009.
- Bryant, Gary, McPhilliamy, Scott and Childers, Hope. April 8, 2002. A Survey of the Water Quality of Streams in the Primary Region of Mountaintop Valley Fill Coal Mining: October 1999 to January 2001. USEPA Environmental Services Division Region 3.
- Neuzil, S. G., Dulong, F. T., Cecil, C. B. Spatial Trends in Ash Yield, Sulfur, Selenium, and Other Selected Trace Element Concentations in Coal Beds of the Appalachian Plateau Region, U.S.A. U.S. Department of the Interior, U.S.G.S. 2005.