Coal slurry impoundment
Coal slurry consists of solid and liquid waste and is a by-product of the coal mining and preparation processes. It is a fine coal refuse and water. Mining generates enormous amounts of Industrial waste|solid waste in the form of rocks and dirt. This refuse is used to dam the opening of a hollow between adjacent mountains. After the dam is built, the void behind it is typically filled with millions of gallons of waste slurry from a coal preparation plant. This impounded liquid waste can sometimes total billions of gallons in a single facility.
High-profile disasters associated with these slurry impoundments have called into question their safety. In February 1972, three dams holding a mixture of coal slurry and water in Logan County, West Virginia failed in succession: 130 million gallons of toxic water were released in the Buffalo Creek Flood. Out of a population of 5,000 people, 125 people were killed, 1,121 were injured, and over 4,000 were left homeless. The flood caused 50 million dollars in damages. Despite evidence of negligence, the Pittston Company, which owned the compromised dam, called the event an "Act of God." In 2002, a long valley fill in Lyburn, West Virginia failed and slid into a sediment pond at the toe of the fill, generating a large wave of water and sediment that destroyed several cars and houses.
Coal slurry contains a large range of constituents, including dissolved minerals that have been leached or washed out of the coal and other rocks. In addition, the slurry contains chemicals added to facilitate the washing or water re-use processes. One of these chemicals is acrylamide. Other chemicals found in the slurry and sludge include the following:
- Benzo(b fluoranthene
- Benzyl alcohol
- Butyl benzyl phthalate
- Dibutyl phtalate
- Diethyl phthalate
- Dimethyl phthalate
- 4-Bromophenyl phenyl ether
- 4-Chhlorophenyl phenyl ether
Drinking water contaminated with hexavalent chromium from coal may cause cancer
A report released by EarthJustice and the Sierra Club in early February 2011 stated that there are many health threats associated a toxic cancer-causing chemical found in coal ash waste called hexavalent chromium. The report specifically cited 29 sites in 17 states where the contamination was found. The information was gathered from existing EPA data on coal ash and included locations in Alabama, Arkansas, Delaware, Florida, Illinois, Indiana, Minnesota, Massachusetts, North Carolina, North Dakota, Nevada, Ohio, Oklahoma, Pennsylvania, Tennessee, Virgina and Wisconsin.
As a press release about the report read:
- Hexavalent chromium first made headlines after Erin Brockovich sued Pacific Gas & Electric because of poisoned drinking water from hexavalent chromium. Now new information indicates that the chemical has readily leaked from coal ash sites across the U.S. This is likely the tip of the iceberg because most coal ash dump sites are not adequately monitored.
- , Ohio Valley Environmental Coalition, Massey Valley Fill Disaster,accessed April 3, 2005.
-  Sludge Safety Project, accessed December 10, 2009.
- "Coal ash waste tied to cancer-causing chemicals in water supplies" Alicia Bayer, Examiner.com, February 1, 2011.