PFAS ubiquitous in Dutch groundwater

Shallow groundwater most affected

In general, substances are present in low concentrations. The highest concentrations of PFAS were found in subsoil groundwater, immediately below ground level. However, PFAS were also found deeper underground and in less recent groundwater. These were mainly PFAS that had not formed a rapid bond to particles in the soil, allowing them to easily spread through groundwater flows.

Connection with PFAS in the soil?

An earlier RIVM study already revealed the widespread presence of PFAS in the soil. The measurements for the groundwater study were partially conducted on the same sites as for the soil study. This made it possible for RIVM to investigate a possible connection between concentrations in the soil and in the groundwater. However, no such connection was found. On sites where the concentration of PFAS in the groundwater is low, RIVM believes that the difference in PFAS concentrations between the soil and the groundwater is caused by various factors, such as rainfall and groundwater flow rate.

Other studies did reveal a connection. According to RIVM, these concerned sites with high local concentrations of PFAS in the groundwater, for example as a result of a fire being extinguished with PFAS containing extinguishing foam. 

The RIVM study (in Dutch, with a summary in English) can be found here.