Radiological situation in the vicinity of Semipalatinsk nuclear test site: Dolon, Mostik, Cheremushka and Budene settlements

Abstract

The present situation of radioactive contamination at the village of Dolon and nearby villages such as Mostik, Cheremushka and Budene was investigated to serve as an aid to resolve dose discrepancy between model calculations and TL measurements made for external gamma-ray dose in air in Dolon. The paper was focused on the reevaluation of the accumulated levels and distribution of long-lived radionuclides 137Cs and Pu isotopes in soil using long core samples up to a depth of 30 and 100 cm. The inventories of 137Cs and 239,240Pu found were in the wide range of 140-10,310 and 140-14,320 Bq/m2, respectively. Most of the Pu in soil was tightly incorporated into various sizes of fused particles. Both 137Cs and 239,240Pu in soil were accumulated in the smaller soil size fraction of <125 microm, and the presence of hot particles, probably due to Pu, was clearly observed by star-like patterns from alpha-tracks. The obtained data will be helpful for evaluating the current and future radiation risks to the people living around there.