Integrated methodology for assessing the HCH groundwater pollution at the multi-source contaminated mega-site Bitterfeld/Wolfen

Abstract

A large-scale groundwater contamination characterises the Pleistocene groundwater system of the former industrial and abandoned mining region Bitterfeld/Wolfen, Eastern Germany. For more than a century, local chemical production and extensive lignite mining caused a complex contaminant release from local production areas and related dump sites. Today, organic pollutants (mainly organochlorines) are present in all compartments of the environment at high concentration levels. An integrated methodology for characterising the current situation of pollution as well as the future fate development of hazardous substances is highly required to decide on further management and remediation strategies. Data analyses have been performed on regional groundwater monitoring data from about 10 years, containing approximately 3,500 samples, and up to 180 individual organic parameters from almost 250 observation wells. Run-off measurements as well as water samples were taken biweekly from local creeks during a period of 18 months. A kriging interpolation procedure was applied on groundwater analytics to generate continuous distribution patterns of the nodal contaminant samples. High-resolution geological 3-D modelling serves as a database for a regional 3-D groundwater flow model. Simulation results support the future fate assessment of contaminants. A first conceptual model of the contamination has been developed to characterise the contamination in regional surface waters and groundwater. A reliable explanation of the variant hexachlorocyclohexane (HCH) occurrence within the two local aquifer systems has been derived from the regionalised distribution patterns. Simulation results from groundwater flow modelling provide a better understanding of the future pollutant migration paths and support the overall site characterisation. The presented case study indicates that an integrated assessment of large-scale groundwater contaminations often needs more data than only from local groundwater monitoring. The developed methodology is appropriate to assess POP-contaminated mega-sites including, e.g. HCH deposits. Although HCH isomers are relevant groundwater pollutants at this site, further organochlorine pollutants are present at considerably higher levels. The study demonstrates that an effective evaluation of the current situation of contamination as well as of the related future fate development requires detailed information of the entire observed system.

Beehold : the colony of the honeybee (Apis mellifera L) as a bio-sampler for pollutants and plant pathogens

“…In the Spittelw asser region the HCH contamination of the soil spreads over about 40 km 2 (Wycisk et al, 2013). In the Netherlands the intervention value of γ-HCH in soil is 2100 µg.kg -1 dry wt.…”

“…The path of pollutants from groundwater through the streambed sediment into the surface w ater was described by Schmidt et al (2008). After the flooding events in 2001, increased HCH concentrations have been detected in fish in the rivers Mulde and Elbe, show ing remobilization of persistent organic pollutants including HCH, from polluted soils, sediments and deposits (Wycisk et al, 2013). Thus frequently flooded floodplains of the rivers Mulde and Elbe and in areas only flooded at high discharge situations, residues of HCH can be expected to be deposited, resulting in HCH polluted streambed and flood plains dow nstream of the polluted areas.…”

“…Waste isomers from Lindane production (α, β, δ and ε-HCH) w ere dumped near the production sites on piles covered w ith soil and in empty open mine pits. Dumping sites of chemical w aste including HCH and disused factories are pollution sources (Manz et al, 2001;Wycisk et al, 2013). After the reunification of Germany, the chemical industry w as redeveloped and the landscape was restored by implementing a large nature redevelopment plan including green landscapes, w etlands and lakes.…”

The need for better management and control of POPs stockpiles

“…Core IHPA themes (www.ihpa.info) addressed in this issue include the management of pesticide/POPs stockpiles (Van Thuong et al 2014;Pieterse et al 2015;Vijgen et al 2011); pollution by HCH and other POPs at former production site (Amirova and Weber 2015; Torres et al 2013;Wimmerová et al 2015;Wycisk et al 2013); and actions and proposals for moving towards solutions for legacy POPs contamination .…”

The need for an integrated approach to the global challenge of POPs management

“…An example of a best-practice approach for the assessment of ground water pollution at a former HCH production site is presented in this issue by Wycisk et al (2012). The study introduces an integrated methodology for assessing HCH ground water contamination from the contaminated mega-site at Bitterfeld/Wolfen in Germany, where approximately 60,000 tonnes of HCH waste isomers was dumped.…”