The impact of a lignite seam on contaminated groundwater in the aquifer system of the bitterfeld region

Until 1990 the Bitterfeld region was heavily polluted by mining, an obsolete chemical industry and the uncontrolled deposition of chemical wastes. The groundwater is extensivly contaminated in the area of a disused chemical factory which once produced and applied halogenated compounds on a large scale. At the research area in Bitterfeld, highly mobile chlorinated aliphatics and aromatics have been detected in both groundwater and sediments, especially in a lignite seam. The modern analytical method of solid-phase micro extraction (SPME) was successfully used to analyse the pollution level of groundwater and sediments. The lignite seam was found to have accumulated large quantities of halogenated hydrocarbons functioning as a giant adsorption filter, and hence recording past groundwater contamination. The vertical and lateral pollution profiles of sediments and the distribution coefficients between lignite and groundwater at equilibrium conditions were determined for the key components. The consequences of the present situation for the progressive groundwater quality of the quaternary aquifer are assessed in a forthcoming article.