Impact of brine on rock mass condition during ‘wet’ closure of potash mines

‘Wet’ closure of a potash mine means planned pumping of brines in a potentially hazardous area. Such area is first isolated by means of construction of special waterproof seals in access ways to this area, and then the mined-out void is filled with a fluid medium. For potash mines, such medium is a mineralized brine. It is planned to take brines from a tailings pond and to resaturate them at a sylvinite processing plant. Then, the brines are to be fed to the mined-out void of a site to be closed through a brine collector of a central pumping station. For the reduction of risk of the adverse induced aftereffects in the planned closure of a potentially hazardous site of a potash mine field, ample research investigations are carried out. Based on prediction of chemical composition of a solution, mutual solubility of salts was studied, and the physicochemical calculations were performed using a dedicated software program. Also, solvability of rib pillars was investigated with the determination of their extraction ratio ∆M, m. For minimizing disintegration of rib pillars, closure of a mined-out void should be carried out with sufficiently saturated brines. During closure of such potash mine site, the brines will be resaturated with NaCl and KCl and will gradually fill the whole void. In the course of the planned control of the pumped brine parameters, in case of detection of their inconsistency with the required values, it is necessary to stop the brine pumping in the mined-out void and to bring the brine to the required standard. 

Skopinov M. V., Konosavskii P. K., Kharkhordin I. L., Potapov A. A. Impact of brine on rock mass condition during ‘wet’ closure of potash mines. MIAB. Mining Inf. Anal. Bull. 2026;(9):54-68. [In Russ]. DOI: 10.25018/0236_1493_2026_9_0_54.

M.V. Skopinov, Director for Design, Director of Mining and Geological Research Section, VNII Galurgii JSC, 614002, Perm, Russia, e-mail: Mihail.Skopinov@uralkali.com,
P.K. Konosavskii, Cand. Sci. (Geol. Mineral.), Associate Professor, Mining Institute of the Ural Branch of the Russian Academy of Sciences, 614007, Perm, Russia, e-mail: konosavsky@dhspb.ru,
I.L. Kharkhordin, Cand. Sci. (Geol. Mineral.), Deputy Director, Geostroyproekt LLC, 199106, Saint-Petersburg, Russia, e-mail: kharkhordin@rambler.ru,
A.A. Potapov, Cand. Sci. (Geol. Mineral.), Associate Professor, Mining Institute of the Ural Branch of the Russian Academy of Sciences, 614007, Perm, Russia, e-mail: potapov@dhspb.ru.

A.A. Potapov, e-mail: potapov@dhspb.ru.

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