Client: USACE Alaska
Location: Anchorage, Alaska
Scope of Work:
- PFAS Site Investigation
Brice was contracted to complete two TOs to conduct a chemical site investigation and provide a Final Chemical Data Report for the JBE054 N/S Runway Extension. Following completion of the first phase of investigation, we were contracted to collect additional data to fill data gaps. The runway construction project involved significant excavation in the vicinity of known/potential contaminated sites. As such, this investigation was scoped to determine if PFAS or other contamination were present within the excavation boundaries. Brice performed the projects in accordance with CERCLA, SARA, RCRA, and USACE, USAF, ADEC, and EPA requirements.
Under the first task order, Brice conducted drilling and sampling. We drilled 33 test borings up to 20 feet below ground surface (bgs) using our Geoprobe 6620 direct push drill rig, collecting soil samples at the surface, 5 feet bgs, 10 feet bgs, and one boring at 20 feet bgs. Brice logged all boring and classified soil in accordance with ASTM standards. We then collected soil samples for chemical analysis for PFAS constituents.
We took field screening readings using a photoionization detector (PID) at each sample interval. Sample intervals from each boring were analyzed for PFAS. In addition, a single analytical sample was collected from each boring at the interval with the highest PID reading and analyzed for GRO, DRO, RRO, VOCs, PAHs, and PCBs. In total, over 370 samples were taken as part of the investigation. Test boring locations were backfilled. Brice delivered the final chemical data report to USACE. PFAS, DRO, RRO, and select VOCs were detected in soil concentrations above project screening levels (PSLs) at 18 test boring locations. Brice’s final conclusions/recommendations included the management/stockpiling of excavated soil at these locations and conducting additional soil borings to properly characterize the vertical and lateral extent of contamination within the excavation area for the JBE054 Runway Extension project.
Under the second task order, Brice conducted additional drilling of 11 test borings and collected 33 samples following similar techniques and approaches from the first task order. Brice delivered the final report to USACE. PFAS and TCE were detected in soil concentrations above PSLs at 4 test boring locations. Brice’s final supplemental conclusions/recommendations included management/stockpiling of excavated soil at these locations and conducting additional soil borings to properly characterize the vertical and lateral extent of contamination in the portion of the excavation area near the Taxiway and Hangar 17.
