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U.S. fracking company Chesapeake Energy has been hit with the largest civil penalty ever imposed for water contamination. Its subsidiary, Chesapeake Appalachia LLC, has entered into a consent decree with the U.S. Environmental Protection Agency (EPA) that states that the company will have to pay a $3.2 million fine for violating the Clean Water Act.

The EPA and the U.S. Department of Justice alleged that Chesapeake Appalachia had discharged sand, dirt, rocks and other fill material into streams and wetlands without a federal permit. The discharge is estimated to have affected about 2.2 miles of stream and over three acres of wetland. The company will be required to spend approximately $6.5 million on restoring a total of 27 sites in West Virginia damaged by the illegal discharge. Of these, 16 sites involved fracking operations, the Department of Justice said in a statement. In addition, Chesapeake Appalachia will have to present the EPA with a comprehensive plan ensuring compliance with federal and state regulation on water protection.

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Robert G. Dreher, acting assistant attorney general of the Justice Department's Environment and Natural Resources Division, commented that by signing the agreement Chesapeake Appalachia was taking important steps to protect wetlands and water supply from contamination. The Environment and Natural Resources Division remains committed to ensuring that oil and gas development complies with the Clean Water Act and other federal laws, he added.