History of Science and Engineering Annotation << Back The First Charge of the Reactor Producing Plutonium for the Atomic Bomb Was of Foreign Uranium B.S. Gorobets Part I of the essay treats the problem of searches for uranium ores in the initial period, in autumn, 1942, of the Soviet Uranium (Atomic) Project. On its start, in the USSR, were known but 5 not great uranium deposits, all whithin Fergana Valley. Their total stocks were equal about 200 t, its mining for radium having been ceased beсаuse of the War. In 1945, when mining recommenced, only 14,6 t of uranium metal have been recovered out from 18 thousand tons of ores, transported down from mountains, essentially by asses. After the nuclear explosions by the USA, in 1945, Soviet hunting for uranium got off at a quickened pace. Searches have been carrying out on Soviet territory, as well as in occupied East Germany and satellite Tchekoslovakia. There were known several high-grade ore deposits of uranium, placed in the Ore Mts, stretching along the frontiere between the two countries. These foreign deposits proved to be the main source of uranium which, after processing, fed up the first soviet uranium-graphite reactor meant for plutonium production (charge consisted of mixture: 150 t 238U with 2 % of 235U). Part II is concerned with «human factor» illustrated by particular events: unusual episodes and persons who acted at the secrete «uranium front». As a whole, a magnificent view openes (though in fragments) presenting the Soviet state and its people working in extremely hard situation, in the end of 1940-ies, over the global problem of their security. Key words: uranium; deposit; Taboshar; the Ore Mountains; Сombine № 6; Director B.N. Chirkov. E-mail bgorobets@rambler.ru