Kazakhmis Corporation:

V. I. Gerasimenko, Chief Mechanical Engineer, Doctor of Engineering Sciences, phone: +7 (71063) 2-32-31

Institute of Mining of the Ural Branch of the Russian Academy of Sciences:

O. V. Zoteev, Head of the Laboratory of Geodynamics and Mining Pressure, Doctor of Engineering Science

Russian State Geological Prospecting University:

A. B. Makarov, Professor, Doctor of Engineering Sciences

In the article some problems arising on deposits finishing are shown by the example of Jezkasgan deposit as a result of insufficiently “pessimistic” prognosis of displacement process parameters. In particular, when chamber-pillar mining system is applied, the earth surface is built over in assumption that displacement processes are securely prevented by the system of abandoned pillars. As practice has displayed, the estimations of long-term pillars stability were carried out everywhere incorrectly: after 30–60 years of service irreversible deformations resulting in earth-surface caving on a large area including, start have originated. The plants, finishing deposits, have No. either technical or economic opportunity to do away with these processes or to localize them. As a result civil population, living in underworked territories, turns to be the most suffering from the decisions formerly accepted.

The analogous processes are mentioned in other old mines, exploiting the deposits by chamber-pillar mining system. For example, in the territory of Verkhnekamsky potassium deposit where at the end of the last century three earthquakes were fixed, one of which was accompanied by the outcrop of caving (the Second Solikamsky mine).

Measures, realized by PA “Jezkasganzvetmet” for providing preservation, safety and secure overland installations exploitation, are considered in the article. The conclusion isdrawn that in similar situations the protected installations removal outside the limits of underworked territory is the most effective. As for designing new deposits development, it is to be conducted with due regard for accumulated negative practice.