Remedial Action-Construction, Campion Air Force Station and Eareckson Air Station, AK

Brice performed a site characterization at the POL Storage Area at Campion AFS, Alaska and remedial action construction at two sites located at Eareckson AS (EAS), Alaska—Transformer Oil Spills at Old Cobra Dane, and the Old White Alice Site. For Campion AFS, we performed the work to identify the appropriate remedial-action construction next steps.  At EAS, Brice implemented the selected remedies— excavation and offsite landfilling, as outlined in the Final Record of Decision. In total, we removed ~1,063 supersacks (~ 5,800 tons) of soil from EAS for offsite disposal consisting of TSCA nonhazardous and non-RCRA characterized soil and debris and TSCA hazardous soil.

Campion AFS. Brice completed the site characterization over the course of two mobilizations. During the first mobilization, soil boring locations were selected based on the former excavation footprints, historical information, and visual observations. For the second mobilization, locations were based on field observations and analytical data from the first mobilization. Brice advanced 60 borings to a depth of approximately 12 feet bgs to vertically delineate contamination. We collected field screening samples using a photoionization detector and analytical samples from each boring. Soil samples were analyzed for organics (GRO, DRO, VOC) and polycyclic aromatic hydrocarbons (PAHs). In addition, eight samples from highly impacted areas were analyzed for extractable petroleum hydrocarbons (EPH) and volatile petroleum hydrocarbons (VPH). Eight background samples were collected from four locations presumed to be outside of the impacted area. These samples were analyzed for DRO (with and without silica gel) and total organic carbon (TOC). Background samples were collected to support silica gel cleanup conclusions and TOC calculations. Brice delivered a final report in accordance with requirements which included recommendations for future remedial-action construction work including excavation, local remediation by landfarming, and excavation and offsite disposal.

Eareckson AS. Brice performed field screening for PCBs prior to excavation. At one site, we excavated to a final depth of 2 feet bgs in 0.5-foot removals and direct loaded the soil into 5-cy Supersacks placed on a 6-mil reinforced liner. At the second site, we reestablished site boundaries and a 30’x30’ historical grid using GPS coordinates. We covered sloped areas which originally contained a vegetated surface with coconut matting to prevent erosion and drove wooden stakes into the regraded soil to hold down the matting along with some excess soil to provide weight in the high wind environment. We excavated soil using a medium-sized excavator. A long-reach excavator was used to reach the farthest NW corner of the grid. TSCA-nonhazardous soil was stockpiled separately within the footprint of contaminated soil and TSCA-hazardous soil was bagged directly into 5-cy supersacks. We staged the supersacks onsite for later transport to a staging to await barge transport for offsite disposal. Following each round of excavation, Brice performed confirmation sampling. We restored the site using gravelly sand from a nearby stockpile except for a couple of sections that still contained PCB contaminations greater than 1 mg/kg which we lined with plastic before being backfilled, compacted, and regraded.