CRS testing grounds
1. Metal splinter at testing ground “4”Nuclear explosions were not the only type of tests carried out on the STS territory. In 1953 – 1957 the STS territory was the area of tesing of combatant radioactive substances (CRS). Combatant radioactive substances were liquid or powder-like combatment radioactive mixtures manufactured either from the wastes of radiochemical industry or by neutron irradiation of specally selected substances in nuclear reactor. Their specific activity ranged from tenths of Curie to several Curie per liter.
CRS tests were made on testing grounds "4" and "4А" situated near northern outpost beyond the Opytnoye Pole (Experimental field). Dispersion of CRS was achieved by blasting of individual shells, bombardment of the area by mortar shells, bombardment from aircraft bombers or dispersion of CRS from airplanes.
Investigations carried out in the past years on the territory of the testing grounds discovered fragments of metal products used in the CRS tests and over 30 areas of local radioactive contamination. 90Sr was the main radioactive pollutant, whose specific activity in upper soil is as high as 5*108 Bq/kg; other radionuclides are presented by isotopes: 239+240Pu, 152Eu, 154Eu, 137Cs, 241Am, 60Co. The areas of radioactively-contaminated soil range from hundreds to hundreds of thousands of square meters with some of them expanding to distances of several kilometers. Concentration of radionuclides in soil and vegetation may be compared with that of radioactive waste.