Lots of contaminated sites are monitored. The most critical chemical substances are periodically analyzed during several years. The question about the interpretation of the series of collected data is then raised : is there a positive evolution of the situation ? Can we see a natural attenuation of pollution? It is nevertheless not so easy to analyse large set of data showing high fluctuations with time.
eOde conducted a detailed analysis of data from a site contaminated with chlorinated hydrocarbons, for the BG Ingénieurs conseils firm and the Canton of Neuchâtel. Simple statistical tools were useful to show clear evidence of natural biodegradation of chlorinated compounds, with some locking points in areas where redox conditions were unfavourable. Advice on remediation and monitoring could then be provided.
More details in the therafter pdf (talk of June 18, 2015, 4th french exchange days on contaminated sites Gesdec – L’Ucie – OFEV in Geneva).