SELECTION AND DIMENTIONING OF THE WATER DRAINAGE SYSTEM FOR DEEP OPEN PITS (THE EXAMPLE OF ASAREL MINE)

摘要

Mine "Assarel" operates the largest copper deposit in Bulgaria. Around 13-15 million tonnes of ore per year are extracted. By 2010 the area of the mine's surface is about 1800 dca, and the mining have reached elevation 720 (initial 1140). For the drying of the masses until 2010 was used a method of underground 3150 m long drainage adit with 12 chambers and 36 drainage boreholes with 10800 m total length, passing the mine field on elevation 720, which has already been reached and destroyed in the working area of the mine. The approved projects envisage the bottom of the mine to reach elevation 555, i.e. excavation with 165 m to the current situation. In future, options for development of the mine to elevation 450 are considered with 270 m below the present level of development. Then, the maximum height of the boards of the mine will reach 690 m.