摘要：Using the probabilistic approach, authors consider the case of development of a dangerous geological phenomenon i.e. the large underground erosive channel, induced by a mechanical suffusion during construction of the pumped storage energy plant in Zagorsk (PSEP-2). Formation of the erosive channel has led to the formation of cavities with the diameter up to 10 metres in the middle and upper-quarternary, suffusion-unstable, the fluvial-and-glacial and lake-glacial deposits of the Moscow and Dnieper moraine. Thin deposits were the bearing basis of the concrete construction of the dam of PSEP-2 in Zagorsk. The lack of proper consideration of difficult engineering-and-geological conditions and the subsequent formation of emptiness has led to the unilateral draft of the building of PSEP-2 in Zagorsk. Draft of the building of PSEP-2 in Zagorsk has detained the start-up of the building into maintenance and has resulted in significant economic damage.
