Example case studies of PFAS investigations in Oregon include:
Portland International Airport ECSI #3324
Oregon's first large PFAS investigation began in 2017 under a voluntary agreement between DEQ's Cleanup Program and the Port of Portland. The primary focus of investigation has been historical fire training areas, where fire training was performed for decades using PFAS-containing Aqueous Film Forming Foam, mandated by the Federal Aviation Administration. In addition to the Port, other parties including the Portland Air National Guard used the Port facilities for live training exercises which included spraying AFFF on structures or on the ground to extinguish fires.
Under DEQ oversight, multiple phases of investigation have been completed by the Port to determine the nature and extent of PFAS environmental releases. While largely focused on soil and groundwater, sampling has also included stormwater and sediment. High concentrations of PFAS chemicals, including PFOS and PFOA, have been found centered on the historical fire training facilities. Recently, investigation has been expanded to include current and former fire stations at PDX. Lower concentrations of PFAS have been detected in soil/groundwater in these areas.
The horizontal extent of groundwater contamination at PDX has largely been defined and does not appear to reach the Columbia River to the north. However, PFAS are present in stormwater discharging to the Columbia River and Columbia Slough. Planning efforts are underway by the Port to reduce or eliminate releases through infrastructure improvements. To date, PFAS have not been detected in the deeper potable aquifers underlying the fire training areas.
A separate PFAS investigation is ongoing at the Portland Air National Guard facility, located in the southern portion of the PDX property, by the U.S. Department of Defense. The investigation is addressing a separate DoD fire training area and multiple locations where PFAS were either stored or used by military personnel.
Salem Army Airfield (Former) ECSI #3868
The Former Salem Army Airfield (Site) is an approximately 81.5-acre facility in Salem, Oregon, near the McNary Field Salem Municipal Airport and operated by the Oregon Army National Guard. The Site consists of multiple parcels of land that are owned by the State of Oregon for ORARNG use and parcels that are leased from the City of Salem. Portions of the Site were historically occupied by the Salem Airport, the U.S. Navy, the City of Salem, and a former carnival equipment production facility operated by Eyerly Aircraft Company.
The Army National Guard has performed Preliminary Assessments and Site Inspections at ARNG facilities nationwide that were impacted by PFAS. The objective of the Site Inspection was to identify whether there had been a release to the environment and determine the presence or absence of PFOA, PFOS, and perfluorobutanesulfonic acid (PFBS) at or above screening levels. The ARNG performed a Site Inspection at the Site in 2019, including collecting soil, groundwater, surface water, and sediment samples. Samples were analyzed for a subset of 18 PFAS, including PFOA, PFOS, and PFBS.
The Site Inspection confirmed that PFAS are present in the Site soil, groundwater, surface water, and sediment. PFOA, PFOS, and PFBS were detected in groundwater. PFOS and PFOA exceeded the groundwater screening levels with a maximum PFOS concentration of 149 nanograms per liter and a maximum PFOA concentration of 58.9 ng/L. PFOA and PFOS were detected in soil below the screening levels; there were no applicable screening levels for sediment and surface water.
In October 2019, the U.S. Department of Defense adopted a policy to retain facilities in the Comprehensive Environmental Response, Compensation, and Liability Act process based on risk-based screening levels for soil and groundwater. The Site will proceed to a Remedial Investigation, the next phase under CERCLA.