Lake Karachay was a small natural lake in central Russia. It is best known for its use as a dumping ground by the Soviet Union's Mayak nuclear weapons laboratory and fuel reprocessing plant. A string of accidents and disasters at the Mayak facility has contaminated much of the surrounding area with highly radioactive waste. In the 1960s, the lake began to dry out and its area had dropped from 0.5 km2 in 1951 to 0.15 km2 by the end of 1993. In 1968, following a drought in the region, the wind carried 185 PBq (5 MCi) of radioactive dust away from the dried bed of the lake, irradiating half a million people. Lake Karachay has been described as the "most polluted spot on Earth" by the Worldwatch Institute.