CONTAMINATION OF ANTHROPIC SOILS WITH HAZ ARDOUS ELEMENTS IN THE NORTH BOHEMIAN BROWN-COAL MINING REGION

In 16 agriculturally reclaimed dumps in the North Bohemian brown-coal mining region in the years 1993 to 1994 their load by hazardous elemen ts was studied. In a set of 81 mixed soil samples taken from topsoil o r humus horizon from a depth of 0 to 0.2 m the content of 10 hazardous elements (As, Be, Cd, Co, Cr, Cu, Ni, Pb, V and Zn) was determined in the extract of 2M HNO3 by the AAS method. The total Hg content was qu antified by the TMA method. The degree of load of anthropic soils (ant hrosoils on dumps) by hazardous elements in different basin districts is documented in Tabs I to III. As is potentially most hazardous eleme nt which exceeds the limit of maximum-permissible values in 18.5% soil samples. Be and Hg are applied locally. As to the districts, in the M ost and Usti nad Labem districts anthropic soils are most loaded by ha zardous elements. This finding corresponds to high immission load of t he whole North Bohemian region which is in the central part of the bas in most adversely affected by industrial exhalations from chemical wor ks at Zaluzi u Mostu and in the eastern part of the basin by immission s from pressure gas plant at Uzin. The acquired values of contaminatio n of anthropic soils by hazardous elements are comparable with the loa d of soils caused by natural pedogenetic process. The level of the con tamination found does not require any sanitary activities.