Environmental geochemical mapping of the Olkusz 1:25 000 scale map sheet, Silesia–Cracow region, southern Poland

Abstract

Detailed, multi-media geochemical mapping has been conducted in the heavily industrialized Silesia–Cracow region in southern Poland. This paper focuses on results for a portion of the region within the Olkusz 1:25 000 scale map sheet as an example. Mapping in the Olkusz area has focused on: topsoils collected from 0–0.3 m; subsoils taken from 0.8–1 m; sediments from streams, ponds, and canals; and surface water. The soils were collected at a sampling density of 16 sites per km 2 . Concentrations of Ag, Al, As, Ba, Ca, Cd, Co, Cr, Cu, Fe, Hg, Mg, Mn, Ni, P, Pb, S, Sr, Ti, V and Zn were determined in topsoil, subsoil and sediments following a hot aqua regia digestion. In addition, organic carbon and grain size distribution were determined in topsoil samples; pH was measured in topsoils, subsoils and surface waters; and conductivity was determined in surface water. Constituents of surface water analysed included Ag, Al, As, B, Ba, Ca, Cd, Cl, Co, Cu, Fe, K, Li, Mg, Mn, Mo, Na, Ni, P, Pb, Rb, Sb, SiO 2 , SO 4 , Sr, Ti, Tl, U and Zn. The results revealed that the soils in the Olkusz map sheet are extremely contaminated with As, Cd, Hg, Pb and Zn in the vicinity of Zn-Pb mines and processing facilities, and that these elements show highly anomalous values in areas where soils were developed on outcrops of Zn-Pb ore-bearing Middle Triassic dolomites. The concentrations of the studied elements decrease exponentially with distance from the sources. The sediments of the main watercourses are polluted with Ag, As, Cd, Pb and Zn. In surface waters of high conductivity and nearly neutral pH, high concentrations of heavy metals and Na, K, Li and SO 4 were observed.