Current radiation situation in near area of air nuclear explosion conducted at Totskoe Testing Ground (Orenburg oblast) on September 14, 1954

Results obtained in 1996–2000 at the Radium Institute on the radiation situation in the epicenter and near trace areas of nuclear explosion conducted at the Totskoe Testing Ground (Orenburg oblast) in 1954 are reviewed, including analysis of available data on the Totskoe 1954 war games and also on global fallout levels typical of the Orenburg oblast. The specific activities of long-lived radionuclides (⁹⁰Sr, ¹³⁷Cs, and ^{239 + 240}Pu) in the soil are determined. At the epicenter, the specific activities of induced radionuclides (⁶⁰Co and ¹⁵²Eu) are determined. The surface and vertical distributions of radionuclides are studied. The contamination levels of the epicenter and near trace areas with explosion-derived radionuclides are estimated taking into account the global fallout levels characteristic of the Orenburg region. For the first time, a comprehensive regular-grid examination of radiation situation in the indicated territory is made. The isotopic composition of Pu in the soil corresponds to that of the global fallout, but not to weapons-grade Pu, suggesting the lack of contamination with long-lived fission products derived from Totskoe 1954 explosion, or indicating that the contamination levels with these products are within the fluctuations typical of the global fallout.Translated from Radiokhimiya, Vol. 46, No. 6, 2004, pp. 564–568.Original Russian Text Copyright © 2004 by Dubasov, Trifonov, Arshanskii, Skovorodkin, Smirnova.