372
T.G. Laperdina et al.
for 5-129 mg/kg, mercury concentrations in suspended matter reaching 8.6 mg/l
(Pfeiffer et al. 1989). Mercury contamination of soils is also registered. In such
conditions the role of vegetative compartments in the biogeochemical mercury
cycle is very important. Mercury accumulates and migrates throughout biotic
components of ecosystems.
As a rule, such a high extent of mercury contamination of the environment in
the areas impacted by gold-mining plants is not registered in Zabaikalye. Besides
climate factors, this is most likely explained, by less mercury expenses in the
process of concentration, a more developed concentration technology and
stricter regulations established by State nature protection committees.
A high level of mercury contamination of the environment is registered in the
area affected by the Luybov mine, according to the mercury content in bottom
sediments of natural water streams (0-42-1.29 mg/kg), which is close to mean
concentrations (1.6 mg/kg), observed at dredge placer workings in South
America. In other mines studied, the contamination extent is lower and at
present not dangerous, though in occasional cases an excess of the MPC for soils
was recorded.
Massive or island spreading of permafrost on the Earth forms about a quarter
of the land area. However, specific mercury behaviour and transformation in
these severe climatic conditions are virtually not studied. As the results of our
studies have shown, the extent of mercury contamination in the areas impacted
by the gold-mining plants of Zabaikalye is significantly lower than in goldmining countries with tropical climate. Therefore, investigations on temperature
correction of chemical and biochemical processes, intensivity determining
quantitative parameters of biogeochemical mercury cycle need to develop globalscale models of mercury emission, migration and balances.
7
Conclusion
As the results of the studies have shown, the contrast and localization of mercury
contamination of the environment in gold-mining areas in Siberia due to the use
of amalgamation technology mainly depend on duration and intensity, and also
on natural landscape and climatic conditions. The most sensitive indicators of
mercury pollution are atmospheric air, soil and bottom sediments of natural and
technogenic reservoirs and streams.
In the context of the official prohibition of amalgamation use, lack of official
centralized supplies of metallic mercury to gold mines and also toughening of
fines for supplies of gold concentrates with an increased mercury content to
refining plants, mercury expenses in amalgamation of gold-bearing raw materials
have sharply reduced. The main mercury users are small scale mines not
possessing enough finances to buy expensive enriching equipment and forced to
use a cheap amalgamation method of gold extraction. At present, the proportion
of such mines in the total amount of gold mines, for example in the Chita Oblast,
T.G. Laperdina et al.
for 5-129 mg/kg, mercury concentrations in suspended matter reaching 8.6 mg/l
(Pfeiffer et al. 1989). Mercury contamination of soils is also registered. In such
conditions the role of vegetative compartments in the biogeochemical mercury
cycle is very important. Mercury accumulates and migrates throughout biotic
components of ecosystems.
As a rule, such a high extent of mercury contamination of the environment in
the areas impacted by gold-mining plants is not registered in Zabaikalye. Besides
climate factors, this is most likely explained, by less mercury expenses in the
process of concentration, a more developed concentration technology and
stricter regulations established by State nature protection committees.
A high level of mercury contamination of the environment is registered in the
area affected by the Luybov mine, according to the mercury content in bottom
sediments of natural water streams (0-42-1.29 mg/kg), which is close to mean
concentrations (1.6 mg/kg), observed at dredge placer workings in South
America. In other mines studied, the contamination extent is lower and at
present not dangerous, though in occasional cases an excess of the MPC for soils
was recorded.
Massive or island spreading of permafrost on the Earth forms about a quarter
of the land area. However, specific mercury behaviour and transformation in
these severe climatic conditions are virtually not studied. As the results of our
studies have shown, the extent of mercury contamination in the areas impacted
by the gold-mining plants of Zabaikalye is significantly lower than in goldmining countries with tropical climate. Therefore, investigations on temperature
correction of chemical and biochemical processes, intensivity determining
quantitative parameters of biogeochemical mercury cycle need to develop globalscale models of mercury emission, migration and balances.
7
Conclusion
As the results of the studies have shown, the contrast and localization of mercury
contamination of the environment in gold-mining areas in Siberia due to the use
of amalgamation technology mainly depend on duration and intensity, and also
on natural landscape and climatic conditions. The most sensitive indicators of
mercury pollution are atmospheric air, soil and bottom sediments of natural and
technogenic reservoirs and streams.
In the context of the official prohibition of amalgamation use, lack of official
centralized supplies of metallic mercury to gold mines and also toughening of
fines for supplies of gold concentrates with an increased mercury content to
refining plants, mercury expenses in amalgamation of gold-bearing raw materials
have sharply reduced. The main mercury users are small scale mines not
possessing enough finances to buy expensive enriching equipment and forced to
use a cheap amalgamation method of gold extraction. At present, the proportion
of such mines in the total amount of gold mines, for example in the Chita Oblast,