Of the total

02.05.2017 | комментариев 0 | раздел: Стены

Coal layers are developed at a depth of 200-450 m long columns for extension (55%of the total production in the pool), a continuous system (18%), inclined layers (26%). Other development systems (shield, chamber and other.) found in the pool very limited use and give less than 1% of the total production of the pool.

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