A new phenomenon has been identified and studied-the impact of bacteria on the benefication process of non-sulphide ores using circulating water supply-a case study of apatite-nepheline ore. It is shown that bacteria deteriorate the floatability of apatite due to their interaction with active centres of calcium-containing minerals and intense flocculation, resulting in a decrease of the flotation process selectivity thus deteriorating the quality of concentrate. Based on the comparative analysis of primary sequences of 16S rRNA genes, there have been identified dominating bacteria species, recovered from the circulating water used at apatite-nepheline concentrating mills, and their phylogenetic position has been determined. All the bacteria were related to γ-Proteobacteria, including the Acinetobacter species, Pseudomonas alcaliphila, Ps. plecoglossicida, Stenotrophomonas rhizophila. A method of non-sulphide ores flotation has been developed with consideration of the bacterial factor. It consists in use of small concentrations of sodium hypochlorite, which inhibits the development of bacteria in the flotation of apatite-nepheline ores.

There have been identified three zones according to the degree of soil pollution with fluoride in the impact area of air emissions of the Kandalaksha Aluminium Smelter (Russia): zone of maximum pollution up to 2.5 km from the emission source with the content of fluoride from 5000 to 1200 mg/kg, zone of strong pollution up to 13 km from the plant with the content of fluoride between 1200-400 mg/kg and zone of moderate pollution up to 20 km from the source with content of fluoride between 400-200 mg/kg. Emissions of the aluminium plant have reduced the number and the diversity of fungi and have caused an increase in fungal communities that are potentially pathogenic fungi. The biomass of fungi has decreased in the organic horizon of the maximum polluted soil from 5.4 to 3.6 mg/g. As a whole, emissions from the aluminium plant in the Murmansk region are less toxic for the environment, than emissions of copper-nickel enterprises.

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A bioplato was organized at Kirovogorskiy pond-settling of OLKON Company (the city of Olenegorsk, in Murmansk region) to reduce the content of nitrogen mineral compounds in water which come into the pond with the quarry waters after blasting operations using nitrogen compounds. The assortment of aboriginal plants was selected, a method of fixing and growing them on the water surface was developed, and observations of their vegetation were carried out. The dynamics of nitrogen compounds was determined in the laboratory and with full-scale tests. The coverage area pond by plants for the effective reduction of mineral nitrogen compounds was calculated. The use of floating bioplato helped to reduce content of ammonium and nitrite to maximum permissible levels or even lower in pond water. Also there was a tendency towards reduction of nitrate concentrations in water. The developmental technology can be used in any climatic zone with a specific assortment of plants-ameliorants.

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