First data of geochemistry and mineralogy of recent sediments of small Lake Komsomolskoye located in Monchegorsk town from Murmansk region (Russia) are presented. The high concentrations of heavy metals were found in surface layers of researched lake sediments. The most accumulation level is initialled for copper and nickel, which are entered to lake from copper-nickel plant complex situated near the arctic town. Other metals also can enter to waterbody in result of activity of this factory complex. In addition, lead, cadmium, antimony, thallium and other elements may be products of the atmospheric transport of pollutants from industries of North and East Europe. Moreover, we have studied main fractions of heavy metals from upper layers of Lake Komsomolskoye and morphology and composition of technogenic particles of nickel, copper, iron and other metals. The origin of these particles is directly associated with the different stages of processing technology of nickel and copper ore on the copper-nickel plant complex (crushing, flotation, roasting, and smelting).