VNIPIpromtekhnologii JSC, Moscow, Russia:

A. V. Gladyshev, CEO

Khiagda JSC, Chita, Russia:
A. N. Mikhailov, CEO
A. V. Suvorov, Chief Geologist

Atomredmetzoloto JSC, Moscow, Russia:

I. N. Solodov, Director of Innovative and Technological Development Programs, Doctor of Geological and Mineralogical Science, INSolodov@armz.ru

Hydrogenous uranium deposits of Khiagda ore field have no equal among commercial uranium reserves recovered by the in-situ leaching (ISL) technology. Khiagda JSC carries out ISL of uranium from four uranium deposits in Khiagda field, namely, Khiagda, Vershinnoe, Istochnoe and Kolichkan. As compared to ore occurrences in alluvium in large paleovalleys and in syneclise-type and grabensyncline type artesian basins in Uzbekistan, Southern Kazakhstan, South Australia and in the TransUrals, Khiagda ore field differs by the fact that uranium sources in the catchment area locate at a distance of a few tens of kilometers from the uranium concentration zones in the reducing geochemical barriers. At the Vitim deposits, the zones of uranium removal from the Vitimkan Complex granite by surface water and groundwater and the zones of uranium concentration under the action of syngenetic and epigenetic reducers in the alluvium–proluvium deposits in paleovallyes are very closely spaced at tens and hundreds of meters to a few kilometers. Some other differences include the mostly phosphate rather than oxide and silica composition of uranium minerals and the near-modern age of ore—1.5–12.5 million years. The breakthrough mining technologies are proposed, such as: nonregular accessing of ore bodies with the nonuniform distribution of uranium; use of sodium nitrite as a uranium oxidizer; groundwater resources management in mining of weakly watered deposits; direct determination of uranium content of ore using the method of neutron–neutron logging. These technologies enhance efficiency of ISL. The further research aimed to improve the process designs is proposed to be focused on optimization of ISL borehole patterns as well as on improvement of groundwater resources management in mining weakly watered deposits.

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