Chagan

Chagan was a Soviet underground nuclear test conducted at the Semipalatinsk Test Site on January 15, 1965. Chagan was the first and largest of the 124 detonations in the Nuclear Explosions for the National Economy program, designed to produce peaceful nuclear explosions for earth-moving purposes. The concept of using PNEs to create artificial lakes, harbors and canals was modeled after the US's Operation Plowshare, which conducted the first peaceful nuclear explosion at the Nevada Test Site in July 1962. Described as a "near clone" of the Sedan shot, Chagan's yield was the equivalent of 140... kilotons of TNT and sought to produce a large conical crater suitable for a lake. The site was a dry bed of the Chagan River at the edge of the Semipalatinsk Test Site, and was chosen such that the lip of the crater would dam the river during its high spring flow. The resultant lake has a diameter of 408 meters and is 100 meters deep.
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