October 21, 2024

Results from ten (10) rounds of surface water sampling conducted in Mare Brook have been provided to the Maine Department of Environmental Protection (DEP). The most recent data was obtained on September 19, 2024, one month after the AFFF release date. PFAS concentrations have been significantly reduced during this time however they remain elevated from pre-spill concentrations. Trends continue to generally decrease as the PFAS works its way through the watershed, and no significant rebound of concentrations have occurred to suggest a further emergency removal effort is warranted. The DEP will continue to monitor surface water into the foreseeable future but plans to reduce the sampling frequency from weekly sample events to monthly, beginning in November. The DEP has also begun submitting samples to its contracted laboratory on a standard turnaround time for analysis which provides results of samples approximately one month after sample collection. These changes to the sampling program were deemed appropriate after reviewing all available data and determining that additional definition in trends provided by sampling frequency will not increase protectiveness to human health or the environment.

This week, DEP staff plan to complete additional soil sampling in the Pond B area. The previous soil sampling event near Pond B was completed in September from an area where appreciable amounts of foam accumulated on the day of the AFFF release. The soil in this area was found to have concentrations of PFAS below the States Remedial Action Guidelines for the park user exposure scenario, but the concentrations were well above background levels for Maine soil. The additional soil sampling will be completed to evaluate potential risk to adjacent site users immediately north and south of Neptune Drive near the Pond B area.

The Department is coordinating with the Department of Marine Resources (DMR) and the Town of Brunswick to conduct additional shellfish sampling in Harpswell Cove in and adjacent to the area currently under an extended seasonal closure. DEP personnel collected softshell clam and blue mussel samples from Harpswell Cove in September and expects to receive PFAS lab results in December. While these results are pending and with help from Brunswick, the Department will collect additional softshell clam, blue mussel and quahog samples in October and November to provide additional data if necessary. DMR will use these PFAS data to support future decisions about reopening or continued closure of the shellfish harvesting area.

On October 16, 2024, the Navy, U.S. Environmental Protection Agency, and DEP project teams met to discuss the initial review of DEP data resulting from the AFFF release at Hangar 4 at the former Naval Air Station in Brunswick. Surface water, soil, and drinking water data were shared with the Navy by DEP to identify trends and preliminary findings. The initial discussions were intended to identify agreed upon next steps under the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) process, but did not address liability, policy conflicts, or final cleanup actions. Action items resulting from the CERCLA project team meetings will be released as soon as consensus has been reached.

A new web map produced by the Department summarizes the surface water, treated wastewater, soil, fish, and private water well samples that the DEP has collected since the AFFF release in August. Visit the DEP BNAS webpage to view the map.

For additional information, contact: David R. Madore, Deputy Commissioner [email protected]