Analyse und Bewertung des subterranen Stofftransfers aus unterschiedlich rekultivierten Halden des Kalibergbaus hinsichtlich ihrer Belastungswirkung auf Fließgewässer

Abstract

Rudolph, F.: Analysis and valuation of the subterrain transport of substances out of different recultivated potash dumps and the ecological consequences for rivers. – Hercynia N.F. 38 (2005): 185 –195.The six (decommissioned) potash dumps in the southern Harz-region (northern Thuringia) are causing an enormous impact to the environment (soil, groundwater, rivers). Every year 500,000 t of potash salts are dissolved and washed out by precipitation. In the 1990’s a pilot-project was started in Bleicherode in order to minimize these leaching processes. The aim of this project was to find (available) biological materials, which are able to infiltrate and retain the precipitation water. The current research project is focusing on the subterrain transport of several substances out of these potash dumps after covering. The questions are, which quantities of percolating waters are discharged in spite of the cover and how are they influenced by pedological and climatic factors? The quality of these percolating waters is of particular importance, because it is possible that, besides the potash salts other harmful substances could be leached out and get into the bordering environmental media caused by the cover-materials (for example building rubble, sewage sludge). Three potash dumps were chosen for this project: two dumps, which actually are in the process of covering in comparison with one, which is uncovered. Tensiometers and suction cups were installed between the base of every dump and the bordering rivers, to measure actual water transport in the soils and to analyse the suction cup solutions. Additionally every dump location has a meteorological station, whose informations are used for estimating the climatic influences of the water transport.