Diffuse groundwater pollution by atmospheric deposition of organic compounds and heavy metals - experiences from SW Germany

At many places all over the world groundwater has become contaminated, mostly as a result of \npoorly designed hazardous waste disposal facilities, leakage fiom Underground storage tanks and \nmine tailings, and accidental spills. Groundwater pollution can also be caused by application of \nfertilizers and pesticides in agriculture. The chemicals trapped in the subsurface constitute a \nmajor long-term contamination source to a groundwater system, resulting in threat to \ngroundwater supply and direct risk to human health, for example by volatilization of toxic \ncompounds. \nOnce a groundwater system becomes contarninated it is almost an impossible task to clean it \nup. Many contarninants are persistent and remain hazardous even at low concentrations. \nThis publication comprises the proceedings of the International Conference on Groundwater \nQuality: Remediation and Protection (GQ'98) held at Tübingen, Germany, in September 1998. \nAs at the two previous conferences in the series, GQM'~(h~el d in Estonia in 1993) and ~4'95~ \n(held in Czech Republic in 1995), the major objectives of the GQ'98 Conference were to provide \nan international forum for state-of-the-art presentations on relevant methodologies and \ntechniques, and to identiS, the needs for future developments. The conference focused on \npractical approaches to assess groundwater quality, viable solutions to contamination problems, \nand methods for protection. Also addressed were directly applicable methods for cornrnon field \nproblems. Of particular interest were: \n- identification of processes and parameters limiting clean up efficiency; \n- methods to assess and monitor groundwater quality at field scale; \n- reactive transport/modelling in heterogeneous environrnents; \n- innovative remediation techniques.