TASS, December 22. The concentrations of non-ferrous metals in soils and plants in the Norilsk Industrial District are above the allowable safe limits by a few times. Scientists explain the phenomenon by the natural conditions dictated by the close proximity of deposits of sulfide ores, reads the final report of the Great Norilsk Expedition of the Russian Academy of Sciences’ Siberian Branch.
“The concentrations of potentially hazardous elements in soils, which develop in conditions of the natural geochemical anomalies of ore fields, may exceed the average concentrations in the crust and the allowable safe concentrations by many times,” the report reads. “From soils the toxic elements get into the plants and make their way along trophic chains. Thus, the region has a high natural and anthropogenic geochemical background of elements, which are typical of sulfide ores in the Norilsk ore cluster – copper, nickel, cobalt, chromium and so forth.”
The Norilsk Industrial District is a major geochemical anomaly, scientists said. The natural geochemical background is typical of all the sediments, which had formed before the district’s industrial development began. It is seen in the geochemical features of sediments in Lakes Melkoye and Pyasino, and in lower parts of surface sediment cores. The ecosystems accumulate big amounts of chemical substances and elements, related to ore occurrence and processing. Those, first of all, are nickel and copper.
“When we compared the natural geochemical background in sediments from Lakes Melkoye and Pyasino, we discovered the naturally uneven distribution of chemical elements,” the document reads. “In Lake Melkoye nickel’s average concentration is 90 ppm (parts per million), which is by 4 times higher than an average concentration in the crust (20 ppm); and copper’s concentration (67 ppm) is more than twice higher (25 ppm) than in the crust.” Lake Pyasino’s lower part of sediments has even bigger concentrations of nickel and copper - 108 and 135 ppm on average, that is by 6 and 10 times higher respectively.
The Norilsk cascade’s lakes – Pyasino, Melkoye and Lama – emerged inside the hollows, formed by the glaciers that were melting down. Each of them is surrounded by a ridge and thus is connected with a separate stage of glaciation, the scientists said.
Expedition to Taimyr
The Siberian Branch of the Russian Academy of Sciences for the first time over recent years, has sent to the Taimyr Peninsula, at the invitation of Nornickel, a big scientific expedition to conduct a large-scale survey of the area. Scientists will use the expedition’s results to present nature-friendly solutions and suggestions for industrial companies, working in the Arctic.
The expedition’s key points were watersheds of the Rivers Pyasina, Norilka and Ambarnaya and Lake Pyasino. In August, experts from 14 research institutes of the Academy of Sciences’ Siberian Branch collected samples of soils, plants and sediments and later began tests at the institutes’ labs.
During field studies at sites of anthropogenic contamination and at conditionally background territories, scientists collected 31 samples of water, made and described 84 soil profile pits of various depths and took 62 samples of soils and 66 samples of plants for further tests.