The Soviets, despite the huge number of irregularities, expanded the combine by adding new reactors and increasing the production of weapons-grade plutonium. This affected the amount of waste produced, much of which was not stored in tanks.
For decades, excess waste was poured into Lake Karachay - the most radioactive place on the planet.
The lake was located not far from the Mayak combine. Data published in the 1990s showed that in the first years of the discharges, 120 million Ci (curie, a non-SI unit of radioactivity) accumulated in the waters, 118 million Ci of which were Cs-137 and Sr-90 isotopes.
In some areas, the radioactivity exceeded 600 R/h, guaranteeing the absorption of a lethal dose of radiation in several minutes. The lake's waters started to dry up in the wake of the 1967 drought, and the wind carried radioactive dust from the bottom of the reservoir over Ozyorsk and southeast of the combine. This led to symptoms of radiation sickness in more than 40,000 people.
Soviets also mined sand from the lake, which was later used to build apartment blocks - some 30 were built, and dosimeters in the apartments tested indicated radiation exceeding the norm by about 10 times.
