ОЦЕНКА СВЕРХНОРМАТИВНЫХ ПОТЕРЬ ПОЛЕЗНОГО ИСКОПАЕМОГО НА ПРИМЕРЕ РАЗРАБОТКИ ИЗВЕСТНЯКОВОГО МЕСТОРОЖДЕНИЯ

Abstract

The article presents methodological provisions for the assessment of increased mineral losses during open-pit mining of deposits with difficult mining and geological conditions. As an example, the indicators of mineral losses during the development of the Kostanok site of the Chanvin deposit of limestones used for the production of caustic soda are given. The actual level of losses exce-eding 30 % of the volume of extraction of raw materials has been established. The main reasons for the increased limestone losses compared to the level justified by the project are outlined. It was found that during the detailed exploration of the limestone massif, karst zones and areas with a high clay content, lying in the form of «veins» in areas of increased fracturing, were not identified. As a result, as a result of blasting, the exploding quarried, clogged areas with pure limestone are mixed, its contamination to values exceeding those allowed by the project, which leads to the loss of balance reserves of minerals during excavation. Recommendations are given for calculating the level of losses during the development of complex faces, which are characterized by the intermittency of rocks with productive limestone strata and karst zones.