The list of restrictions, including spatial, temporal, geological, economic, regulatory, etc., within which the mining enterprise operates as a natural-technical system is given. The general scheme of a natural-industrial system and the restrictions which determine the conditions for its functioning is given. It is stated that any natural-industrial system being a sophisticated complex dynamical system is at the same time an inertial system which quality is important for its operation and management decisions. A scheme of functioning of a naturalindustrial system in time has been presented. The process of its functioning is described. With regards to complexity of environmental issues and environmental legal regulations in mining, a risk assessment approach is proposed which is based on taking into account the external limitations and impacts of different origin, related to environmental safety restrictions. Based on the conclusions of different authors the need to consider a mining enterprise as a dynamic “natural - industrial” system which is permanently under impact of changing external factors is demonstrated. An example of changes of environmental legal regulations as one of the external impacts is given.An example of changes in one of the external limitations that determine the risks of environmental management decisions is given. An analysis of changes in the legal requirements for hazardous wastes management over the past 20 years (from 2000 to 2019) is presented. The possible consequences of these changes for mining enterprises are described.. In addition, the risks that arise for mining enterprises in the event of failure to comply with these environmental requirements are described as well. Conclusions are drawn about the possible areas of application of the approach given in the article.

The nitrogen compounds, namely ammonium, nitrite and nitrate nitrogen, are the main substances polluting the quarry and drainage waters of mining enterprises that use the ammonium nitrate-based explosives for drilling-and-blasting rock mass preparation. In accordance with the legislation, such waters are subject to treatment prior to discharge into the water bodies. At the mining enterprises, the promising treatment method is the treated water conditioning in the flooded abandoned open-pit mines, during which the natural microbiological nitrification of ammonium and nitrite nitrogen contained in the quarry drainage waters is performed with an efficiency of more than 95%. The article discusses the influence of natural climatic and hydrodynamic factors on the nitrification process according to the results of a purification process study that has been performed since 2014 until the present time at a large mining enterprise. The relevant conclusions and recommendations are given.

The article analyzes the mechanism of contamination of quarry waters during drilling and blasting preparation of asbestos-containing raw materials under the influence of man-made and natural factors, which can serve as a basis for making specific technological decisions that reduce the negative impact on the environment during the development of chrysotile-asbestos deposits. The dependence of the intake of nitrogen compounds in quarry waters on the consumption of explosives and the volume of formation of quarry waters is presented. The article shows the possibility of using the purification of quarry water in the spent open mine workings, the sides of which are composed of plastic asbestos-containing rocks. The relationship between the volumes of internaldumping and contamination of open pit drainage waters is analyzed.

Based on the multicomponent analysis of the recovery voltage curve, a new approach to assessing the condition of electrical insulation has been justified that allows one to monitor changes in the volume charge state and electric conductivity of insulation using the results of one measurement. For cables with impregnated paper insulation, this approach enables one to monitor typical defects in operation, such as dry ing out the impregnation compound and humidifying the insulation along the entire trajectory of its aging from unfailing up to marginal state.

Typical pollutants, whose content in drainage waters of mining enterprises exceeds the maximum permissible concentrations, are nitrogen compounds -ammonium, nitrite and nitrate nitrogen. Their presence in drainage waters is a consequence of the use of explosives based on ammonium nitrate (NH4NO3) for preparing the rock mass for excavation. The article presents the results of studies performed in quarries of a large mining enterprise, which justify the possibility of preliminary natural treatment of drainage waters of mining enterprises from nitrogen compounds in exhausted open-cast excavation. Natural purification occurs due to two processesthe first is a natural nitrification of the ammonium ion NH4 + and the nitrite ion NO2-to the nitrate ion NO3-(the nitrate ion represents the least environmental hazard of these nitrogen compounds) with prolonged storage of drainage water in exhausted open-cast excavation in the presence of atmospheric oxygen. The second is a dilution of drainage waters in open-cast excavation by natural underground waters and atmospheric precipitation entering it in a natural way. The results of the studies given in the article became the foundation for the development of the project for the enterprise purification system for drainage water, which successfully passed state expertise and is currently being implemented. The use of preliminary natural treatment of drainage water from nitrogen compounds in exhausted open-cast excavation significantly reduced the cost of the project and subsequent post-treatment at specialized biological treatment facilities, which is especially important in the current economic situation.Keywords: pollution with nitrogen compounds; natural biological treatment; drainage water.Типичными загрязнителями, содержание которых в дренажных водах горных пред-приятий превышает предельно допустимые концентрации, являются соединения азота -аммонийный, нитритный и нитратный азот. Их наличие в дренажных водах является следствием использования взрывчатых веществ на основе аммиачной се-литры (нитрат аммония NH 4 NO 3 ) для подготовки горной массы к экскавации. В ста-тье приведены результаты исследований, выполненных в условиях карьеров круп-ного добывающего предприятия, обосновывающие возможность предварительной естественной очистки дренажных вод горных предприятий от соединений азота в отработанной открытой горной выработке. Естественная очистка происходит за счет двух процессов: естественная нитрификация иона аммония NH 4 + и иона нитрита NO 2 -до иона нитрата NO 3 -(ион нитрата представляет меньшую экологи-ческую опасность из указанных соединений азота) при длительной выдержке дре-нажных вод в отработанной открытой горной выработке в присутствии кислорода воздуха; разбавление дренажных вод в отработанной открытой горной выработ-ке природными подземными водами и атмосферными осадками, поступающими в нее естественным путем. Результаты исследований, приведенные в статье, были использованы при разработке проекта системы очистки дренажных вод предприя-тия, который успешно прошел ...