Comprehensive environmental monitoring during remediation of a nuclear legacy site in the Far East of Russia

Abstract

In compliance with the fundamentals of the government’s policy on nuclear and radiation safety, Russia is continuing to implement its national program for decommissioning its nuclear legacy. Under this program, the State Atomic Energy Corporation, ‘Rosatom’, is carrying out decommissioning and remediation of the Navy’s former shore technical bases (STBs) in the Russian Far East. Along with the ‘old problems’ accumulated during the operation of STBs in the past, new challenges arise because of the planned intensification of radioactive waste (RW) management on the site in the nearest future. The paper presents the results of comprehensive environmental monitoring at the site of temporary storage for spent nuclear fuel (SNF) and RW at Sysoeva Bay, located in Primorsky Krai. One of the site’s features is the cross contamination of the environment with radioactive substances and nonradiological pollutants. The dominant radionuclides in the environmental media are 137Cs, 90Sr, and a minor contribution from 60Сo. The soil contamination with artificial radionuclides predominantly relates to the category of industrial waste with local areas classified as very low-level RWs. The contamination penetrated the underground water via migration from the damaged SNF and RW storage facilities. Along with cesium and strontium radionuclides, widespread groundwater pollution with heavy metals (I–III hazardous classes), including Be and As, was revealed. Moreover, the exceedance of permissible levels of Cd reaches 1000 times, and that of radionuclides (90Sr)reaches 50 times. It dictates the necessity to improve the environmental impact assessment by accounting for the nonradiological pollutants in monitoring design. The radiological conditions in the residential area are characterized by the regional background levels. The average annual effective dose of public exposure due to artificial sources does not exceed 40 µSv.

Building optimization into the process for decommissioning, remediation of legacy sites and facilities, and management of the wastes arising: results of an international workshop

“…The experience gained from this site has been applied at other sites, e.g. see Kiselev et al (2021). Australian regulatory experience in optimization in decommissioning and legacy management was presented for two very different legacy situations: remediation of a former uranium mining site that had initially been abandoned without any rehabilitation when mining was no longer economic; and the Little Forest Legacy Site, an old disposal facility for low-level radioactive waste.…”