Preliminary investigation of contaminated sites

In the agricultural area of a Zurich municipality, there are two large, old landfills where municipal waste and building rubble used to be deposited. Both landfills were entered in the register of contaminated sites as requiring investigation and the municipality was requested by the Office for Waste, Water, Energy and Air (AWEL) to carry out a preliminary investigation of the two sites. Ecosens AG then carried out a historical investigation of both sites and drew up a specification for the technical investigation for the relevant soil and groundwater protection goods. Once the specifications had been approved, a total of four groundwater measuring points were set up and numerous groundwater and soil samples were taken and analyzed. The investigations showed that the contaminated sites do not pose a risk to the environment, meaning that the classification under contaminated sites legislation could be adjusted.