VNIPIpromtekhnologii R&D Institute, Moscow, Russia:

E. V. Kuzmin, Head of Research Laboratory, Professor, Doctor of Engineering Sciences, EViKuzmin@rosatom.ru

“Atomredmetzoloto” JSC, Moscow, Russia:
V. S. Svyatetsky, Vice-Chief Executive Officer – Operating Officer

Priargunsky Mining and Chemical Works, Krasnokamensk, Russia:
V. V. Markovets, Head of Radiation Safety Laboratory

Over the period of 50 years-long mining and processing of uranium ore, Priargunsky Mining and Chemical Works has accumulated round 75 Mm³ of radioactive waste in surface tailing storages. In this respect, the problem of such waste management was and remains of the highest concern. The tests on preparation and application of paste backfill made of thickened uranium ore mill tailing in underground mined-out stopes are implemented, the rheological properties and strength of paste backfill with added binders are determined. There are a number of methods to reduce radon emission from paste backfill. One of the methods consists in addition of a binder which increases density of the backfill mix and, thereby, complicates radon emission. Addition of a few percent of cement unchanges density of radon flow. Fly ash admixture also has no influence on radon flow density. Introduction of 3–10% of barite, the heaviest nonradiating natural material, fails to change radon flow, as well. It is expected to change density of radon flow only in case of considerable increase in quantity of material addition. Efforts to abate radon emission from paste backfill to underground mine air are suggested. The closedcycle technology of uranium mining and processing is validated and developed. As a result of the accomplished research, new critical decisions are made on safe disposal of current and old tailings of mining-and-metallurgical works in the form of cemented paste backfill for large stopes (room-andpillar mining, sublevel stoping) and other kinds of mined-out voids in underground mines.

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