In January - March 2020, DHEC sampled and analyzed community drinking water wells near Shaw Air Force Base (AFB) in Sumter, South Carolina for per- and polyfluoroalkyl substances (PFAS). The focus area for sampling was approximately a three (3) miles radius surrounding the Base property boundary within which 13 community water systems were sampled. Shaw AFB is one of the Department of Defense sites where PFAS were known to be used for training with fire-fighting foam. Perfluorooctanoic acid (PFOA) and perfluorooctane sulfonic acid (PFOS) are the two most commonly-produced and studied of the PFAS group. In 2016, the US Environmental Protection Agency (USEPA) issued a drinking water Lifetime Health Advisory (LHA) of 70 parts per trillion (ppt) for PFOA and PFOS, either individually or combined.
The purpose of sampling was to determine:
- The presence and concentrations of 14 PFAS compounds measured using USEPA Method 537.1.
- Whether PFOA and PFOS were present at an individual, or combined, concentration greater than the USEPA LHA of 70 ppt.
The locations of the community water systems sampled are shown in the Exhibit Map. The results from this sampling are summarized in the table. All results have been provided to:
- the owners of the water systems
- the customers of the mobile home park systems that exceeded the USEPA LHA
- Shaw AFB to help inform the Base’s response to the surrounding communities
The accumulated water quality data for the SAFB investigation are summarized in this table.
Exceedances of the USEPA LHA were observed at four of the 13 systems. Three of these were mobile home parks; the fourth was a business. Routine chemical analyses of the mobile home parks’ water wells and sanitary surveys of the mobile home parks’ water systems were performed.
As a part of the Department’s community engagement efforts, DHEC personnel were on-site and visited with residents of the mobile home parks. In these visits, we provided to those interested a communications packet about the sampling results, a PFAS Fact Sheet, and a point-of-service activated carbon water filter.
We also answered questions residents had about their drinking water, including steps to mitigate or reduce potential exposure.
The water systems that did not have exceedances of the USEPA LHA were encouraged to share their results with their customers and to enhance their knowledge and understanding of PFAS compounds as related to their systems.
*Page last updated 8/07/2020 at 10:34 AM.