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

CONCLUSIONS Hydrochemistry Freshwater systems are sinks for pollution, because pollutants are transported from the surrounding landscape into the streams and lakes. The watercourses in the Russian, Norwegian and Finnish border area consist of two contrasting types of system: the large Inari-Paz watercourse and the numerous small lakes and streams. The Inari-Paz watercourse has important environmental properties, is rich in natural resources, and constitutes a sub-arctic system with high biodiversity and production of fish and other aquatic organisms. The area is, however, subjected to severe anthropogenic impacts, primarily from the Pechenganikel smelter complex. The main pollutants that influence the lakes and rivers are sulphur compounds and heavy metals (Ni, Cu, Cd, Cr, Zn, As, Hg etc.), polycyclic aromatic hydrocarbons (PAHs) and persistent organic pollutants (POPs). Sulphur dioxide (S 0 2) emissions from the smelter can lead to the acidification of surface waters and the contamination of groundwater through the leaching of pollut­ ing elements from the surface soil. For example, data on the contribution of snowmelt to groundwater in the area indicate that Ni contamination is highly likely. Joint investigations carried out in the early 1990’s identified numerous acidified and heavy metal polluted lakes in the border area. The impact of pollution is the greatest at Russian and Norwegian sites in the vicinity of the smelters, although the effects are also seen on the Finnish side of the border. The area was classified as being moderately to very severely contaminated, primarily due to emission from the Ni-Cu smelting industry on the Kola Peninsula. Some of the differences and changes in water quality reflect the influence of the Pechenganikel smelter. The strongest evidence for this are the high Cu (>3 \ig l'1) and Ni (> 15 |igl'1) concentrations in the lakes near the smelter.Water bodies with elevated Cu and Ni concentrations occur within a 30 km radius around the smelters. The Cu and Ni concentrations decrease with increasing distance from the smelter, although relatively elevated concentrations also occur near to the border on the Finnish side. According to the Swedish water quality criteria, harmful biological effects may occur in sensitive waters if the Cu concentration exceeds 3 |ig1-1 or the Ni concentra­ tion exceeds 15 |ig l'1. Moiseenko et al. (1995) presented critical levels for Ni and Cu concentrations in lake waters based on the occurrence of pathological conditions in fish. The critical levels in well-buffered waters (ANC >200 |ieq l'1) were 8 |ig l"1for Cu, and 20 |ig l"1for Ni. The Cu concentrations in 8 lakes exceed these critical levels, and the Ni concentration in 12 lakes and 2 small rivers. There is also a weak, increasing trend in the Ni concentration in the lakes in the Raja-Jooseppi area, and a statistically non-significant increase in the TOC concentration. The catchments of the lakes in the Raja-Jooseppi area have a higher proportion of peatland than the other areas studied, resulting in higher humic concentrations. Although S 0 2 emissions from the Pechenganikel smelter have decreased to ap­ proximately one third of the maximum levels in the late 1970s, sulphur deposition still has a clear impact in the region. The sulphate concentrations in lakes and rivers in the vicinity of the Pechenganikel smelter are considerably higher than those in other areas. Despite the high sulphate concentrations, the lakes and rivers in the area are well- buffered and are not suffering from acidification. The bedrock in the Pechenganikel area contains relatively large amounts of alkaline material, thus ensuring a consider­ Catalogue o f Lakes in the Russian, Finnish and Norwegian BorderArea