Coal mining negatively influences the environment. It pollutes the landscape, atmosphere and surface waters not only in the areas close to mines, but also at some distance. The worst ecological situation is in the regions where there is a great concentration of coal mining and processing industries, ironworks, machine-building and coal fuel chemistry.

   Coal mining enterprises produce large amounts of mine (colliery) waters. About 3-10 m3 mine waters/ton of worked coal flow into the hydrologic network. Qualitative composition of colliery waters is various; it differentiates in different coal-fields, deposits and regions. Their dumping into the drainage network causes siltation, salification, acidulation of water bodies and waterways, thus creating misbalance in coal basins. Constant deepening of mining works and complication of hydrogeological situation lead to increase of the amount and pollution of the taken waters as well as depletion of underground water bearing strata, including those with fresh drinking water. Mines in Donbass pump out all the mineralized waters from the mine works.

   Water treatment at one of the largest mining enterprises of Donetsk region – Zasyadko mine – is carried out by the methods of water clarification, water disinfection, treatment and utilization (or storing) of sediments.

   During the flow of mine waters from the source of their contamination (production faces, etc) to the dumping onto the surface their purification from sedimentary particles takes place underground (in underground drain sumps) at different levels. In these conditions only primary purification of mine waters is possible (to 50-150 mg/dm3).

   To the existing facilities providing technological purification of waste (mine) water belong mine drain sumps, central pumps of the main pumping, mine level sumps and chlorination plants.

   Clarifying ponds are on the balance of “Administration of extinguishing soil restoration”. Cleaning of clarifying ponds is carried out according to the special project by a specialized organization, which has a corresponding license, after undergoing an examination. The description of the mining waters drainage scheme. Mine water flows through the grooves to the drain sumps of level 1078m, from where it is pumped to the sumps of level 800m. Then, it is pumped to the sumps of the main pumping, which is situated on the level of 529 m. From the sumps of the main pumping it is pumped onto the surface into 3-section horizontal sump (clarifier). After clarification and disinfection mine water is discharged into the pond, shared with Feliks Kon mine.

   Mining enterprises are characterized by excess of waste waters amounts over water consumption to meet the demands of production.

   Because of high level of watering of mines they annually pump onto the surface about 850-960 mln m3 of underground waters. Only 13.5-15.2% of this amount is used on the demands of production, the rest being discharged into the surface water bodies. They make about 2/3 of total water intake used on the needs of mines.

   Mine waters pumped onto the surface are contaminated not only with fine-dispersed carbonic mixture (suspended solids), but also with mineral salts. According to analyses of observations of many years the content of suspended solids can be up to 700 mg/l, which is 7 times more than the standard. Zasyadko mine pumps water with contamination 3-5 times more than the norm. It is connected with the fact that the mine management does not pay much attention to prerefining of mine water in the underground conditions, opportune refinement of gutters and sumps at shaft stations.

   It is possible to define the following main contaminating substances in waters pumped from mines: coal and rock dust, clay particles, chlorides, free sulphuric acid and corresponding saline compounds - ferric sulfate, dissolved and suspended phenol compounds, oils. To the contaminating factors the high temperature of mine waters and drainage can be referred. Mine waters can not be used even for technical needs without refinement or neutralization because of the presence of chlorides, sulphides, calcium, magnesium, natrium and potassium. When these waters flow into the surface waters they are included in the natural circulation. Under favourable conditions they are deposited in the soil, bottom sediment, then get into plants, animals, and – due to this – into human organisms.

   Biogeochemical processes that go in the water objects and soil in connection with deposits development can be compared to natural ones, conditioned by wind and water erosion, weathering of mine rocks. However, when natural processes go very slowly, not misbalancing the geosystems greatly and not worsening the current ecological situation, the negative influence of mining activity misbalances the ecosituation greatly. As the contaminating substances spread at big distances, local influence of Zasyadko mine becomes regional. Zasyadko mine discharges manufacturing waters into the river Kalmius, which flows on the whole territory of Donetsk region and into the Azov Sea.

   Considering the current ecological situation in the region the following conclusion can be done. Treatment facilities of industrial enterprises cannot cope with the industry growth rate. To solve this problem in the region, including Zasyadko mine, it is necessary to reconstruct the currently working treatment facilities or to develop (or project) a new scheme of mine waters treatment. The most promising way of solving this problem is to decrease fresh water consumption and minimize the amount of discharged mine waters at the expense of introduction of recycling or closed-circuit water supply systems.