ATMOSPHERIC EMISSIONS OF INERT RADIOACTIVE GASES FROM REACTOR AND RADIOCHEMICAL PRO DUCTION FACILITIES OF THE FEDERAL STATE UNITARY ENTERPRISE MAYAK PA AND THEIR RADIOLOGICAL IMPACT

The paper considers the parameters of earlier existed (1948—2024) sources of inert radioactive gas (IRG) emissions associated with the Mayak’s reactor and radiochemical production facilities to support the establishment of scientifically based dose quotas for atmospheric krypton-85 ( ⁸⁵Kr) emissions proposed for a new large radiochemical SNF reprocessing plant. The study evaluates the following parameters: radiation characteristics of all IRGs that could have been released into the atmosphere; the reconstructed IRG emissions; the calculated near-surface activity concentration and external radiation doses due to IRG emissions for the populated areas in the plant’s immediate vicinity; measured accumulated external radiation doses. The study shows that the calculated external radiation doses for the Ozersk residents in 1948—2024 provided their permanent exposure to the IRG emissions from the reactor production in the open area amount to (9—13) mSv, which seems to be in good agreement with the experimental data from direct measurements (1959—1989) and retrospective thermoluminescent dosimetry (1948—2006). As it comes to adult residents of the Ozersk city, it indicates that all through the operational life of the enterprise (1948—2024), the total effective dose of external exposure caused by ⁸⁵Kr emitted from all stacks of the radiochemical and reactor production facilities did not exceed 1 μSv, which is ~ 100,000 times less than the annual threshold (1 mSv/year). ...

Keywords: inert radioactive gases, krypton-85, atmospheric emission, radiation characteristics, external radiation dose, radiochemical plant, radioactive waste.

Mokrov Yu. G. Atmospheric Emissions of Inert Radioactive Gases from Reactor and Radiochemical Pro duction Facilities of the Federal State Unitary Enterprise Mayak PA and their Radiological Impact. Radioac tive Waste, 2025, no. 1 (30), pp. 44—56. DOI: 10.25283/2587-9707-2025-1-44-56. (In Russian)