http://en.wikipedia.org/wiki/Nuclear_Explosions_for_the_National_Economy--snip--
Problems
Among the most cited catastrophes was the Kraton-3 explosion in Vilyuy, Yakutia in 1978, that was supposed to unearth a large amount of diamond-rich ores. Instead the amount of diamonds was insignificant but the plutonium pollution of the water sources was much higher than predicted. According to Yablokov, the level of plutonium in the drinking water of Vilyuy region twenty years after the explosion is ten thousand times higher than the maximal sanitary norm.
Another catastrophe resulted from the Globus-1 explosion near village Galkino, 40 kilometers from Kineshma city on September 19, 1971.<4> It was a very small underground explosion of 2.5 kilotons that was a part of the seismological program for oil and gas exploration. Unexpectedly a large amount of radioactive gases went out through the cracks in the ground, creating a significant highly radioactive spot of two kilometers in diameter in the relatively densely populated area of European Russia. To make things worse, a small tributary of the Volga, the Shacha, changed its location and threatened to flood the very hole of the explosion. This could have led to nuclear pollution of the entire Volga region. Some engineers suggested building a sarcophagus (similar to the Chernobyl's "Object Shelter") over the place of the explosions and digging a 12 km channel to shift the Shacha river away from the place of the explosion, but the plans appeared prohibitively expensive.
The experiments came to an end with the adoption of a unilateral moratorium on the testing of nuclear weapons at Soviet test sites in 1989. Although this primarily was designed to support Mikhail Gorbachev's call for a worldwide ban on nuclear weapons tests, the Russians apparently also applied the moratorium to peaceful nuclear explosions as well.
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