Water treatment plant upgrades to remove PFAS, with 100% cost recovery

The City of Martinsburg, West Virginia, USA, detected perfluorooctanoic acid (PFOA) and perfluorooctane sulfonic acid (PFOS), two types of per- and polyfluoroalkyl substances (PFAS), in its Big Springs water source at concentrations exceeding USEPA’s 2016 Lifetime Health Advisory. As a result, the city closed its Big Springs water filtration plant until it was able to provide treatment of these compounds.

Working with the client from 2016 to 2022, Ramboll performed initial pilot testing and concept level designs for alternative approaches that would remove the PFOA and PFOS. Pilot studies included rapid small-scale column tests (RSSCTs) to confirm the effectiveness of granular activated carbon (GAC) for the Big Springs source water.

Following the pilot studies and concept designs, Ramboll was retained for final design, construction management and startup services for the upgrade project, all on an expedited schedule. This approach allowed the City to resume use of its Big Springs water treatment plant.

With a treatment capacity of over 5 mgd, the new system is one of the largest installed to date in the US for the treatment of PFAS.

Construction was completed on a fast-track schedule, with the system going into partial operation 10 months after starting design and treating PFOA and PFOS to below detection levels. The superstructure was then installed around the operating GAC contactors.

Ramboll has provided operational support to the city during the first three years of operation, including a sampling program to determine the rate of GAC exhaustion for the full suite of PFAS compounds, additional RSSCTs to compare alternative GAC media, and procurement of GAC change-outs. Ramboll also supported the city in successful negotiations with the federal government for recovery of all capital and operating costs.