Radioecological Situation in the Region of Gorizont-4 Underground Nuclear Explosion in Sakha Republic (Yakutia)

Resumo

The modern radioecological situation on the site of the Gorizont-4 underground nuclear explosion and on the adjacent territories is analyzed. The maps of the exposure dose rates and concentrations of natural radionuclides (⁴⁰K, ²³⁸U, ²³²Th) on the territory including the explosion epicenter are constructed. The modern levels of the global fallout of ¹³⁷Cs, ⁹⁰Sr, and ^239,240Pu in the soil and plant cover and in foodstuffs were determined on the site. The current annual internal dose for the population of the Kyusyur village due to consumption of foodstuffs containing ¹³⁷Cs and ⁹⁰Sr was determined. It is lower by two orders of magnitude than the annual dose limit for population. The underground nuclear explosion performed in the mid-1980s did not affect significantly the radioecological situation on the adjacent territories, including the Kyusyur village.