STATE AND STRENGTH-DEFORMABILITY PROPERTIES OF THE MIRNY MINING AND PROCESSING PLANT (MPP) TECHNOGENIC TAILINGS DAM DEPOSITS AS A FACTOR OF DAM STABILITY

The occurrence and development of exogeodynamic processes caused by liquefaction and fluidity of deposits that comprise the mine tailings dam may provoke emergency situations (breakthroughs). To prevent such situations, objects like these are covered by regular geomonitoring.

The article presents the results of the study of the current state of the technogenic tailings dam deposits of the enrichment factory No.3 of the MPP (Mirny, Yakutia). Severe climatic, structural-geological and permafrost-hydrogeological conditions of the study area, as well as the thawed state of the technogenic strata (+0.5 to +3.1 °C) require to carry out a thorough control over the state of the dam in order to ensure its effective and safe operation.

Studies of the material composition and properties of technogenic deposits were carried out based on the data on five drilled 31–58 m deep boreholes and sampling intervals. The granulometric and mineralogical compositions, as well as physical, physical-chemical and mechanical properties were determined according to standard methods using modern equipment (Analysette 22 NanoTec granulometric analyser, automated test complex ASIS).

It has been found that the technogenic strata are layers of loose rock represented mainly by silty-clayey (sandy loam, loam and clay), less often by sandy material. Most of the clay varieties transform from solids to fluid-plastics. The most common lithological variety is silty loam, comprising ~40 % of the total volume sampled. The mineral composition of sediments is characterized by a high content of dolomite, calcite, quartz, serpentine and clay minerals. All clay deposits types have been found to have low strength (C=0.003–0.050 MPa, φ=3.9–15.7°) and high deformability (E=1.6–5.6 MPa). They also exhibit "dangerous" process-forming properties – plasticity, fluidity and flowability, which give rise to the development of exogenous geological processes (erosion, slumps, landslides, etc.), and consequently, influence the stability of the mine tailings dam.

1. Aniskin N.A., Malakhanov V.V., Antonov A.S., 2016. Analysing the Operation of the Drainage System of the Dam of the Tailings Dump of Mirny Mining and Processing Plant. Vestnik MGSU 12, 91–102 (in Russian) DOI:10.22227/1997-0935.2016.12.91-102.

2. Brown G. (Ed.), 1965. The X-Ray Identification and Crystal Structures of Clay Minerals. Mir, Moscow, 599 p. (in Russian)

3. Drozdov A.V., Iost N.A., Lobanov V.V., 2008. Cryohydrogeology of Diamond Deposits in Western Yakutia. ISTU Publishing House, Irkutsk, 507 p. (in Russian)

4. Gotovtsev S.P., Klimovsky I.V., 2020. On the Geocryological Studies on the Southern Part of Western Yakutia. Arctic and Subarctic Natural Resources 25 (2), 81–86 (in Russian) https://doi.org/10.31242/2618-9712-2020-25-2-6.

5. Gusenkov S.N., Stefanishin D.V., Finagenov O.M., Shulman S.G., 2007. Reliability of Tailing Facilities of Enrichment Plants. Vezelitsa, Belgorod, 674 p. (in Russian)

6. Hubbard C.R., Snyder R.L., 1988. RIR – Measurement and Use in Quantitative XRD. Powder Diffraction 3 (2), 74–77. https://doi.org/10.1017/S0885715600013257.

7. Islam K., Murakami S., 2021. Global-Scale Impact Analysis of Mine Tailings Dam Failures: 1915–2020. Global Environmental Change 70, 102361. https://doi.org/10.1016/j.gloenvcha.2021.102361.

8. Ivanov I.P., 1990. Engineering Geology of Mineral Deposits. Nedra, Moscow, 302 p. (in Russian)

9. Lolaev A.B., Butiugin V.V., 2005. Geological and Ecological Problems of Industrial Hydraulic Engineering in Cryolite Zone. Nedra, Moscow, 240 p. (in Russian)

10. Lomtadze V.D., 1990. Physical and Mechanical Properties of Rocks. Methods of Laboratory Research. Nedra, Leningrad, 328 p. (in Russian)

11. McFadden T.T., Bennet F.L., 1991. Construction in Cold Regions: A Guide for Planners, Engineers, Contractors, and Managers. John Wiley & Sons, New York, 615 p.

12. Okhotin V.V., 1933. Granulometric Classification of Soils on the Basis of Their Physical and Mechanical Properties. OGIZ-Lengostransizdat, Leningrad, 70 p. (in Russian)

13. Osipov V.I., 1979. Nature of Strength and Deformation Properties of Clay Rocks. MSU Publishing House, Moscow, 232 p. (in Russian) [Осипов В.И. Природа прочности и деформационных свойств глинистых пород. М.: Изд-во МГУ, 1979. 232 с.].

14. Osipov V.I., Karpenko F.S., Kalbergenov R.G., Kutergin V.N., Rumyantseva N.A., 2017. Rheological Properties of the Clay Soils. Geoecology. Engineering Geology, Hydrogeology, Geocryology 6, 41–51 (in Russian)

15. Phukan A., 1985. Frozen Ground Engineering. Prentice Hall, Englewood Cliffs, N.J., 336 p.

16. Posukhova T.V., Dorofeev S.A., Garanin K.V., Gao Siaoin, 2013. Diamond Industry Wastes: Mineral Composition and Recycling. Moscow University Geology Bulletin 68, 96–107. https://doi.org/10.3103/S0145875213020087.

17. Rotta L.H.S., Alcântara E., Park E., Negri R.G., Lin Y.N., Bernardo N., Mendes T.S.G., Filho C.R.S., 2020. The 2019 Brumadinho Tailings Dam Collapse: Possible Cause and Impacts of the Worst Human and Environmental Disaster in Brazil. International Journal of Applied Earth Observation and Geoinformation 90, 102119. https://doi.org/10.1016/j.jag.2020.102119.

18. Sokolov V.N., 1996. Microcosm of Clays. Soros Educational Journal 3, 56–64 (in Russian) [Соколов В.Н. Микромир глинистых пород // Соросовский образовательный журнал. 1996. № 3. С. 56–64].

19. Yannikov A.M., Korepanov A.Yu., Struchkova A.S., 2024. Features of the Formation of Natural-Technical Systems Within the Injection Areas of the Daldyn Kimberlite Field (Western Yakutia). Bulletin of the Tomsk Polytechnic University. Geo Assets Engineering 335 (9), 61–72 (in Russian) [Янников А.М, Корепанов А.Ю., Стручкова А.С., Особенности формирования природно-техногенных систем в пределах участков закачки Далдынского кимберлитового поля (Западная Якутия) // Известия Томского политехнического университета. Инжиниринг георесурсов. 2024. Т. 335. № 9. С. 61–72]. https://doi.org/10.18799/24131830/2024/9/4455.

20. Zhang R.V., 2014. Geocryology Principles of Earth Dams for Low and Medium Pressures in Permafrost in a Changing Climate. Fundamental Researches 9 (2), 288–296 (in Russian) [Чжан Р.В. Геокриологические принципы работы грунтовых плотин в криолитозоне в условиях меняющегося климата // Фундаментальные исследования. 2014. Т. 9. № 2. С. 288–296].