An innovative ground water remediation technology has been introduced to convert contaminated aquifers into purifying filters, eliminating PFOA and PFOS contaminants, manufacturer Regenesis said in a press release.
Recent site data collected from an industrial site in Eastern Canada where PlumesStop liquid active carbon was introduced into a PFAS contaminated aquifer has been shown to be at non-detect for over 15 months and counting. Modelling of the remediation estimates treatment to last as long as 100 years with one application of the PlumeStop.
Rick McGregor, President of In Situ Remediation Services, was first to demonstrate this new approach for treating PFAS chemicals using PlumeStop. McGregor designed the application of the amendment to address petroleum hydrocarbon contaminants (PHC) found on an industrial site in Eastern Canada where he also noted a former fire-training facility. Prior to the injection application, and as part of his remedial approach, McGregor included testing for PFAS levels which were confirmed. Once PlumeStop was applied, McGregor began monitoring activities and found that PlumeStop effectively treated the PHC contaminant levels as well as the PFOS and PFOA contaminants, reducing all pollutants to non-detect. Continued monitoring at the site shows levels remaining at non-detect for over 15 months.
The longevity of the approach was verified by Grant Carey, president of Porewater Solutions, who is an expert in ground water contaminant fate and transport modelling, NAPL characterization, and environmental forensics.
Using field data supplied by McGregor, Carey explored a number of conservative, modelled scenarios which presumed ongoing secondary inputs of PFAS from infiltration, desorption and back-diffusion from the aquifer matrix. Data were modelled for PFOA, the most abundant species detected at the site. Modelling was performed for scenarios assuming PlumeStop capture based on measured concentrations in the aquifer before treatment and under a conservative scenario where concentrations were assumed to be 10X measured concentration. In all cases, the PlumeStop applied to the site was shown to affect PFOA capture in excess of 100 years, by which time the secondary inputs would be effectively depleted.
The innovative liquid carbon amendment effectively eliminates a number of soil and ground water contaminants like BTEX, TCE, PCE, the company said. The technology now adds PFAS chemicals like PFOA, and PFOS to the growing list of toxic and carcinogenic pollutants that can be cost-effectively treated, addressing threats to water resources.