One Billion gallons of coal ash sludge, the residue from burned coal in water, surged out of a holding pond after an earthen retaining wall burst at a coal power plant in Harriman, TN on December 22, 2008 destroying homes and property, and contaminating waterways [click image to enlarge]. The 40 acre holding pond at the Kingston Fossil Plant, a coal-burning electrical power plant, contained decades worth of ash deposits piled 55 feet high. (see previous blog post for Map and more photos)Coal ash has long been known to contain dangerous concentrations of heavy metals, but for days, Tennessee Valley Authority (TVA) officials maintained that the sludge released is not toxic. Residents feared for their health, and complained that the authority had been slow to issue information about the toxicity of the coal ash and sludge released into river water.
A week after the ash dam burst, TVA along with the Environmental Protection Agency (EPA) recommended avoiding direct contact with the ash sludge, and that children and pets should be kept away from it. The EPA also recommended that anyone exposed to the ash sludge should wash thoroughly with soap and water and wash the affected clothes separately from other garments.
Federal officials cautioned residents who use private wells or springs to stop drinking the water, and not use it for cooking or bathing. Arsenic in a sample taken from the nearby Emory River was higher than the maximum level allowed for drinking water. Elevated levels of arsenic can cause ailments ranging from nausea to partial paralysis, and long-term exposure has been linked to several types of cancer, according to the EPA. Sampling in the vicinity of the Kingston water plant, which is upstream of the spill, and of the water being served by Kingston showed no violations of drinking water standards. The EPA press release is here.
Residents were also concerned about breathing the ash particles if the massive ash deposits and mounds throughout the area dry out and become airborne. Initially, they were told by TVA President and CEO Tom Kilgore that wouldn't happen because it's rainy and damp. One week later, however, the TVA indicated that they will install sprinkler systems to moisten the ash.
Arsenic is not the only toxic chemical in coal ash. To get some sense of what else is in the ash and the quantities involved, the Institute for Southern Studies examined the Kingston facility's Toxics Release Inventories (TRI) filed with the EPA back to 1998 and included the 2007 TRI emissions data from the TVA website. Their findings are summarized in the table below:
[click image to enlarge]Coal ash contains known human carcinogens including Arsenic, Chromium, Mercury, Nickel and polycyclic aromatic compounds, as well as suspected carcinogens including Lead and Cobalt. Mercury and Lead are toxic to the nervous system and can cause developmental problems. A number of the chemicals in the ash have been linked to reproductive problems. Barium, when ingested in drinking water can cause acute gastrointestinal disturbances and muscle weakness as well as kidney damage over time. Vanadium has been linked to respiratory problems, birth defects, and kidney and liver damage.
The Institute for Southern Studies notes limits to the data, including that it is self-reported by the company with no independent verification, looks at only select chemicals and excludes some pollutants found in coal such as radioactive elements, and only goes back to 1998 while Kingston plant has been in operation since 1955. Nonetheless, the data does give a sense of some chemicals of concern present in the ash and thus the potential health risks. The full report from the Institute for Southern Studies is here.
Tennessee Governor Phil Bredesen promised greater oversight of coal ash retention ponds after viewing the disaster on December, 31. "Burning fossil fuel for electricity is a dirty business," he said. "Everywhere this happens there are huge ash piles, there are environmental issues. My dream out of all of this is maybe this is an epiphany for TVA and for the country that some things have got to change", he said.
The Senate Committee on Environment and Public Works will hold a hearing January 8 on the Tennessee Valley Authority and the ash spill, and testimony will be provided by TVA President and CEO Tom Kilgore, environmental advocates and local officials who responded to the disaster.
UPDATE Friday, January 2, 2009: Independent tests of the river water near the Kingston power plant were performed at the Environmental Toxicology and Chemistry labs at Appalachian State University in Boone, NC. Scientists found Arsenic levels from the Kingston power plant intake canal at close to 300 times the allowable amounts in drinking water, while a sample from two miles downstream still revealed arsenic at approximately 30 times the allowed limits. Lead was present at between twice to 21 times the legal drinking water limits, and Thallium levels tested at three to four times the allowable amounts.
Toxicity levels of heavy metals in the water were deemed a cause for concern to humans, as well as for aquatic life's ability to survive and reproduce in waters with these levels. The full report is here and the river sites tested are shown in a Map here.
UPDATE #2: The EPA has finally disclosed it's quantitative test results on the river water. The water sample from the Emory River near the spill site showed total Arsenic levels 149 times the maximum acceptable level, total concentration of Lead five times above normal, and slightly elevated total levels of Beryllium, Cadmium and Chromium. Samples taken near the Kingston water treatment plant, which is upstream from the spill site, were found to be within the federal limits, except for Thallium, which was found at levels three times the maximum limit. The news report is here.
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