Some fields of the mines being in operation in the Far East do not border upon the shelf of the Okhotskoye, Japan and Beringovo seas. This fact forces the miners to leave much coal in productive pillars. The officials of the department of Mining Mineral Resources of the Far East of State Technical University and Joint stock Company ""Primorskugol"" are carrying out considerable scientific researches to create new technologies of mining solid minerals under sea floor without disturbance of the sea floor. The researches have determined parameters of the present technology of the extraction and the depth of mining coal seams under water-bearing levels and the sea floor. The method of gasification and borehole hydraulic mining are modem methods of working coal seams. The procedure of complex investigation and practical application of the methods of working coal seams under water reservoirs may be successfully used while creating ecologically good technologies of mining useful minerals such as coal and ores, building materials and gold dust under the sea floor.
The Pacific Ocean Basin shelf is extremely rich in mineral deposits, which require development and application of modem ecologically good techniques of their extraction The reserves explored best of all are coal seams of the operating mines, gold-bearing, titanium- magnetite and cassiterite sands and other mineral resources. The objective of scientific researches is to develop ecologically acceptable techniques of useful hard mineral extraction from the face of the seabed preserving the marine fauna and environment.
Coal seams extraction from the surface of the seabed is considered to be one of such techniques. One of the main problems of the mineral extraction under reservoirs is the determination of safe depth for the extraction which is usually connected with the physical and mechanical properties of rocks and methods of roof control, determining the jointing development and water permeability of rocks in the underworked width.