Sandimirov S.S. Catalogue of lakes in the Russian, Finnish and Norwegian Border Area. Finland, Jyvaskyla: Kopijyva Oy, 2008.

industries, and also to the deposition of airborne pollutants. The main pollutants are sulphur compounds and heavy metals (Ni, Cu, Cd, Cr, Zn, As, Hg etc.). S 0 2emissions from the smelter have resulted in the oxidation of the surface water, as well as pollution of the groundwater due to the leaching of elements from the soil surface. Maximum concentrations of Cu (7.2 |_ig/l) and Ni (93 |_ig/l) were recorded in the water in the 1990s. At the present time, although the airborne deposition load has been reduced, there are higher concentrations of Cu (up to 15.2 |ag/l) during flood periods when the snow cover melts, and of Ni (up to 182 |_ig/l) during high precipitation episodes in the summer. 1.19.2. Lake bottom sediments Lake Kuetsjarvi receives, via the River Kolosjoki, most fo the effluent from the Pechen­ ganikel smelter. As a result, the main pollutants are Ni, Cu and Co, as well as the chal­ cophile elements Pb, As, Cd and Hg.The sediments of Lake Kuetsijari have relatively low organic matter contents: the LOI value in the uppermost 1 cm layer is 20% (Table 22). The most polluted layer is the top 10 cm of the lake sediments (Fig. 32). The pol­ lution factor values of these toxic elements range from 11.6 to 125.7 (Table 22), i.e. the values correspond to high contamination. Ni has the highest Cf value. The degree of contamination value (240.1) for this lake corresponds to high contamination, and has one of the highest values in the River Paz watershed. Lake Layer, cm LOI Cu Ni Zn Co Cd Pb As Hg Cd Kuetsijari 0-1 21-22 21.42 10.67 1343 40 4032 32 297 127 184.1 15.9 3.14 0.10 45.7 4.5 43.05 2.62 0.417 0.049 Cf 33.5 125.7 2.3 11.6 32.1 10.1 16.4 8.5 240.1 Table 22. The organic matter contents (LOI, %) and heavy metal concentra­ tions (цд/д, dry weight) in the surface (0-1 cm) and pre-industrial (21-22 cm) sediment layers. Cfand Cdare con­ tamination factor and degree ofcontamination values, respectively. 0 S 5 О Cu - g i o g 1 1 5 •ТЭ о с у: 2 0 1000 1500 Cu, H-g/g G u lf Stream Kolosjoki Salmijarvi Whit Stone Fig. 32. Vertical distribution of the concentrations of Ni, Cu, Pb and Cd (цд/д, dry weight) in sediment cores from differentparts o fLake Kuetsjarvi. 0 1 2 3 Cd, p.g/g G u lf Stream Kolosjoki Salmijarvi Whit Stone Catalogue o f Lakes in the Russian, Finnish and Norwegian BorderArea 69