Because of the remediation systems installed at the base, the full-scale source area regenerable resin PFAS remediation system has successfully treated groundwater with a total influent average PFAS concentration of 48 µg/l since April 2018. The treated water quality from the SORBIX RePURE resin system has been consistently non-detect for PFOS and PFOA compounds, readily achieving compliance with the 0.07 µg/l HAL target. The ECT2 team has made operational modifications to address and correct minor challenges with the resin regeneration system. Additionally, regenerant recovery and related waste minimization processes have proven highly effective. After more than 16 months of operation, no PFAS waste has needed to be hauled off-site.
The IX resin results were similarly successful in the City’s public water supply pilot test. The influent total PFAS concentration averaged 3.5 µg/l over the course of the year-long evaluation. The IX resin substantially outperformed the GAC on all 12 PFAS that were present at detectable levels. The GAC column was operated until PFOA and PFOS breakthrough reached 0.07 µg/l at the 10-minute EBCT. This occurred at approximately 13,000 bed volumes (BVs), roughly 2.5 months into the test. By contract, the IX resin effluent from the shorted (2.5-minute) EBCT column remained well below the 0.07 µg/l HAL, even after treating more than 171,000 BVs over a 12-month period. Based on the results of the comparative pilot test, the City selected IX resin for full-scale implementation to remove PFAS from the Haven well supply.
The City’s engineer, Weston & Sampson, led the evaluation and attributed the selection of IX resin to the smaller footprint and lower capital and O&M costs associated with ECT2’s technology. The full-scale system is scheduled to commence operation in 2020.