As of October 2011, remedial action at most site areas has been completed. Remaining site work includes post-treatment groundwater monitoring at Sites 1, 2, 3 and 11, and work to address petroleum releases at an on-site diesel generator and in an unlined ditch near the fueling area oil/water separator.
In December 2011 DEQ reviewed and approved a report for the oil/water separator ditch release. The report presented the results of ditch sampling and risk screening, and concluded that residual contamination from the release does not pose a significant risk to public health or the environment.
Semi-annual monitoring in the Site 2 and 11 areas is ongoing. In September 2012, DEQ determined that no further action is necessary in the Building 433 diesel spill area. Also in fall 2012, DEQ reviewed and approved a work plan for additional investigation in the so-called Surplus Area, a portion of the ANG site that is not being used by the Guard and will apparently be returned to the Port of Portland. Soil and groundwater under the approved plan is pending.
Leaking sewer have also been identified as a concern in the southern site. The Guard is presently seeking funding for sewer repair and related investigation work under DEQ.
April 2013. Post-treatment monitoring indicates that groundwater contaminants in the Sites 1,2,3, and 11 areas are below remedial action levels. ANG's consultant has requested proceeding to NFA. DEQ is in general agreement, but has requested one additional round of sampling for two wells to confirm contaminant trends. Based on April 2013 sampling results, DEQ has deterimined that Site 1, 2, 3, and 11 treatment and monitoring is complete.
Surplus area sampling has been completed, and generally identified no or low levels of contamination. A modest amount of followup investigation has been requested. Following additional sampling, soil in a low-lying portion of the Surplus with elevated PAHs was covered with a minimum of two feet of clean fill as part of ditch abandonment activity. Soil from the "dogleg" portion of the soil stockpile remains on-site, and has modestly elevated PAHs. Off-site disposal of the soil at a Subtitle D landfill is pending. A summary of Surplus work is presented in the October 2013 Final Phase II EBS Site Assessment Report received by DEQ.
A work plan for closeout activities at the Portland ANG site under the Environmental Restoration Program/DSMOA with the Guard has been approved. Closure will include all of the so-called Portland ANG "Sites" including Sites 1, 2,3, and 11 where solvent plumes were present. Closure will not include "side" projects with Portland ANG including assessment of impacts associated with leaking sewers (soon to be replaced), and an oil/water separator which will be upgraded.
A final work plan for investigation activities at the former vehicle maintenance area (Building 188) has been received. Sampling is expected to take place in April or May 2013. Update: sampling has been completed, and no significant contamination was detected. A Revised Final Site Investigation Report for Building 188 was approved by DEQ in December 2013.
(May 2014, DJH). DEQ was contacted regarding a jet fuel release (spill), and completed a site visit. A localized of perhaps 40 gallons of fuel occurred. ANG has sampled the impacted (soil) area, and results are pending. The spill will be addressed through DEQ's Cleanup Program. Separately, repair of the on-site sanitary sewer system has begun, and a RFP will be issued shortly by the Guard for site-wide closure activities under the Environmental Restoration Program.
(June 2016, DJH). Site closure for all DSMOA investigation/cleanup areas is ongoing, with a final closure document to be submitted to DEQ in 2016. Only minor contaminant issues remain, the most notable being a pending investigation (2017) by the Guard to assess whether perfluorinated compounds have been released onsite associated with use of flame retardant chemicals.
(February 2017, DJH). Closure report for Sites 1, 2, 3, & 11 received by DEQ and currently under review.
September 2017, DJH). DEQ issues a letter concurring with ANG's NFRAP determination for Sites 1, 2, 3, 11. SI-level investigation of perfluorinated compounds will occur in early 2018.
April 2018, DJH. PFAS investigation work plan (Phase III) finalized and submitted to DEQ April 2018. Multi-media (soil, groundwater, stormwater, and sediment) sampling was completed by contractor in summer 2018. Results received in October, and plans for follow-up investigation (SI) by DOD are pending.
November 2018. PFAS detected in soil, sediment, surface water, and groundwater. Results presented in Site Inspection Report (October 2018). Followup investigation by Guard currently being planned.
January 2019. Final Site Inspection (SI) report presented addressing DEQ comments. PFOS+PFOA detected to 42,970 ng/L in shallow groundwater, and 1,