Lake Karachay

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Lake Karachay, sometimes spelled Karachai, is a small lake in the southern Ural mountains in western Russia. According to a report by the Washington, D.C.-based Worldwatch Institute on nuclear waste, Karachay is the most polluted spot on Earth. The radiation level in the region near where radioactive effluent is discharged into the lake was 600 röntgens per hour (approximately 6 Sv/h) in 1990, according to the Washington, D.C.-based Natural Resources Defense Council, sufficient to give a lethal dose to a human within an hour. [Wiki]