Firefighting foam is so effective due to its ability to coat the fuel source and prevent its contact with oxygen, suppressing the flames. It is its PFAS chemical makeup that allows it to be heat resistant.

At a site in Germany, previously used as agricultural land, a fire extinguisher factory producing and testing fire extinguishers on site operated from 1953 to 2007. In 2008, PFAS were detected in the sewage sludge prompting extensive site investigations which also discovered elevated PFAS concentrations in soil, groundwater, surface water, and discharge water on site, and on two neighbouring properties. Our team planned a remedial response and excavation, focusing on two main zones:

  • The former on-site Fire Training Area (FTA) – this was the main source area for PFAS in soil. Once discharged, run-off accumulated in a downgradient pond located on the neighbouring property and via the on-site sewer lines into the public sewer system. We excavated the impacted soil, sealed the site, then backfilled with clean soil. A new drainage system was installed and connected to the separator on-site, to divert storm water drainage into the on-site sewer line.
  • Pond on neighbouring property – Following the property clearance, the pond sediments were excavated. It was then sealed and backfilled with clean soil. New drainage prevents direct contact between contaminated soil and humans, and eliminates the possibility of future recontamination with potentially impacted groundwater.

Ongoing groundwater monitoring on the site now shows significantly decreased PFAS results in local groundwater and in the site’s discharge water. We helped mitigate our client’s liability issues and provided cost savings for long term clean-up at the site. Good planning and transparent communication with all involved provided sustainable and long-lasting relationships with the relevant regulators, the site owners, and the neighbouring properties.