Marker compound contamination area

Figure 1. Topographic map showing the area of contamination of the marker compound in groundwater and surface water. Area covers 5x6 km. Designated points are described in the text.

In the subsurface system, however, there is concern about concentrations of contaminant compounds in drinking water. Both shallow and deep wells have been found to contain the marker compound in this system. More information is needed to fully assess the various areas of the aquifer impacted to date and rates of transfer between them especially because changes can occur in aquifer systems when groundwater pumpage increases. The transport of residuals of these substances in flood plain and channel bottom sediments must be better understood to assess the nature of the release into ground and surface water in the future. 

Butyl tin compounds were detected in the core layers representing an input time since approx. 1970. This observation agrees very well with the initiation of a large scale production in the area investigated. The concentration profile reveals a significant increase to the upper layers until approx. 1980. However, thereafter a sharp decrease in the top layer was observed corresponding to a similar contamination trend in all other industrial markers. 

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