Plague Soviet weaponization

Countering the Chemical and Biological Weapons Threat in the Post-Soviet World, p.l7 I. Brodie, Russia Has Broken Its Germ War Pledge , The Daily Telegraph, 1 September 1992, p.l J. Barry, Planning a Plague Newsweek, 1 February 1993, pp.20-2. 

Unlike anthrax, plague bacteria do not form spores, therefore are much more susceptible to environmental stresses and usually die after several hours of exposure to sunlight. Nonetheless, compared to other bacteria that do not form spores, plague bacteria are hardy. (The Soviet Union weaponized it for their BW arsenals, but American scientists—during the heyday of the US BW program—were unable to master the technique of mass producing Yersinia pestis.)... 

By March of 1949 flte corroded coolant channels had been replaced, the graphite had dried, and the A Reactor was ready for restart. Unfortunately, the same troubles plagued the reactor as before. Stuck fuel slugs, cooling water flow variations, and core power fluctuations resulted in less than optimal plutonium production. Despite all of this, by midsummer 1949, a sufficient quantity of plutonium had been removed from the reactor to be processed into relatively pure Pu and assembled into a weapon. The first Soviet nuclear detonation took place at the Semipalatinsk test site on August 29, 1949. 

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