Radioactivity in waterways near a top-secret nuclear weapons complex in Siberia is higher than what would be released from 10,000 commercial nuclear reactors, making it the worst nuclear river contamination ever uncovered, U.S. and Russian watchdog groups announced this week. Between 1955 and 1967, the Soviet Union commissioned five nuclear reactors at the Siberian Chemical Complex to produce weapons-grade plutonium. All five should be shut down by now, under a 1992 agreement by the U.S. and Russia, but two are still operating. The watchdog groups, which said they were shocked at the “staggering” pollution levels, suggested that the complex may have also been the site of other, unacknowledged nuclear activities, and they are calling for the International Atomic Energy Agency to send an emergency response team to the area. “The nuclear waste is being piped straight into the environment,” said Norm Buske, an American physicist who went on the monitoring trip.

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