Catalogue of Lakes in the Russian, Finnish and Norwegian Border Area = [Каталог озер в приграничном районе России, Финляндии и Норвегии] / Nikolay A. Kashulin, Vladimir A. Dauvalter, Sergey S. Sandimirov etc. - Apatity : Institute of the North Industrial Ecology Problems KSC RAS etc., 2008.

mg/1) and sulphate (average 117 mg/1) predominating. Intensive pollution of the water body was observed throughout the monitoring period. Pollutant concentrations are currently very high. The annual chemical cycle of the lake is characterized by a decrease in the total mineralization of the water to 40.2 mg/1 and a drop in pH during floods and times of high precipitation. During low-water periods (summer and autumn) the total miner alization increases to 467 mg/1, the oxidizability decreases and the pH rises. The concentrations and relationships between the species of mineral nutrients vary according to the season, and the dynamics is to a greater extent determined by the level of production and, consequently, the trophicity of the water body. The highest total P concentration in the lake (up to 25 fig/1) typically occurs in autumn, and it is 3 times higher than the concentration in spring and summer. The highest total N concentra tions (up to 1760 |ig/l) also typically occur during flood periods. According to the concentrations of min eral nutrients, the lake is classified as eu- trophic. The lake also has colour values and organic matter concentrations (up to 3.7 mg/1) typical of small water bodies in the region. The mean Fe concentration is 214 [ig/l.The trophic type of the water body is to a great extent determined by the proximity of the town of Zapolyarny and the smelter. The bottom of the lake is covered by a thick layer of silt of technogenic origin. The watershed area of Lake Haukilampi is subjected to major anthropogenic impacts from the “Pechenganikel” smelter, and the water system to effluents from the concen tration plant. The main pollutants are sul phur compounds and heavy metals (Ni, Cu, Co etc.). In the 1990s the maximum con centrations in the water were Cu 11 p.g/1and Ni 111 pg/1. Pollution emissions during the monitoring period have resulted in higher concentrations of Cu (up to 16 |ig/l) and Ni (up to 167 |ig/l). 1.1.2. Lake bottom sediments The sediments in Lake Haukilampi are characterized by high organic matter con tents: the LOI (loss in weight on ignition) value in the uppermost 1 cm layer is more than 35% (Table 1). The lake is located at a distance of 3 km from the Pechenganikel smelter complex, and is exposed to high levels of e.g. Ni, Cu, Co, Zn and chalcophile elements (Pb, As, Cd and Hg) emitted from the smelter. The layers most polluted by Ni, Cu and Zn are located in the top 7-8 cm of the lake sediments. This layer is also seriously polluted by chalcophile elements (Fig. 1), suggesting that atmospheric emis sions from the smelter are the main sources ofpollution in the lake. The contamination factor values for these toxic elements range from 2.2 to 85.1 (Table 1), i.e. the values indicate considerable and high contamination according to the classification of Lars Water colour, deg. 12 5-21 NH4, цд/І 70 8-213 N03, цд/І 571 1-1700 Total N, ng/l 927 250-1760 po 4, мд/і L5 1.0-2.0 Total P, (jg/l 9 1-25 Fe, цд/l 214 48-430 Cu, цд/І а л 4.7-16.0 Ni, цд/І 109 18-167 72 Al, цд/І 46-93 0.2 Pb, цд/І 0.1-0.3 Catalogue o f Lakes in the Russian, Finnish and Norwegian BorderArea