Distribution and environmental impact of coal-mining wastes in Upper Silesia, Poland

About 50 million tonnes/year of waste rock from coal-mining is generated in the limited area of the thickly populated Upper Silesian Coal Basin (USCB) in Poland. There are 380 coal-mining waste dumps, including 76 active dump sites covering over 2,000 ha. About 15-16 million tonnes/year ready of was te rock is being reused for civil engineering of wa,ses in the same area. T his brings about a problem of ground water deterioration by constituents le ached from waste rock exposed to atmospheric conditions. The major factors determining ther ground water contamination potential from waste rock are c hloride salinity, sulfur content and acid generation potential. The concept behind the presented studies was to provide data for correct evaluation an d prediction of contaminant release from the waste rock, based on the chara cterization of coal-mining waste properties, as well as on long-term labora tory, lysimetric and field studies. The results show that coal-mining waste dumps can be a long-term source of ground water contamination, lasting for decades and increasing with time. Ground water down-gradient from the disused 15-30-years-old part of the stu died dump displays used high and increasing acidification, high TDS, SO4, a nd the highest, still increasing concentrations of great Mn, Fe and Zn. Cos t-effective and efficient pollution control measures, similar to the presen ted design and construction elements of the dump site, can mitigate the neg ative environmental impacts.