Former Naval Surface Warfare Center Annapolis

Environmental

Historic Environmental Investigation

Environmental investigations began in 1985, with a Preliminary Assessment (PA), the first step of the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) process. A second was completed in 1990.  In 1991, a Site Inspection (SI), the second step in the CERCLA process, was completed, based on recommendations of the 1990 PA.  In 1995, in anticipation of the BRAC and transfer of the property, an Environmental Baseline Survey (EBS) was completed. In 2000, a Remedial Investigation (RI), the third step in the CERCLA process was completed.

The RI Identified two potential source areas: an evaporation pond associated with the former burn pad due to the presence of polycyclic aromatic hydrocarbons (PAHs); and an area are to the north of the pad, where a soil sample contained elevated pesticides. The subsequent human health and ecological risk assessments indicated that as long as the facility was not going to be used for residential purposes, no clean-up would be needed. Figure 3 shows the location of the former burn pad and evaporation pond, septic field, and missile silos.

A Record of Decision (ROD), the CERCLA step that completes the investigative phase, was signed in 2001. The selected remedy, was a deed restriction prohibiting the facility from being used for residential purposes. Further, because the ROD did not allow for unrestricted use of the facility, 5-year reviews were also a component of the selected remedy. Finally in 2001, a real estate document that presents the environmental history of the facility, a Finding of Suitability to Transfer (FOST) was generated, paving the way for the transfer of the property.

5-Year Reviews

The ROD was signed in 2000 and the first 5-year review was completed in 2005 and the second in 2010.  Both reports noted that the remedy was working as intended and that the site remained protective of human health and the environment. In 2015, in Section 7, Technical Assessment the 5-year review noted:

"Records were identified that indicate an AFFF extinguishing system was located next to a concrete pad about fifty yards from a main fire testing area, near the north end of the present Children’s Theater. No specific reference to [PFAS] in the AFFF system was identified, however, given the dates and nature of fire test and fire suppression research conducted, [PFAS]-based AFFFs were presumably used at some time prior to 1986 at Bay Head Road Annex."

The 4th 5-year review is currently under development and will be posted to this site when it is complete.

Remedial Investigation

Following notification to the Navy of the potential for PFAS, the Navy informed its regulatory partner, the Maryland Department of the Environment (MDE) and began planning for a large, multi-media (soil, sediment, surface water, and groundwater) investigation.

Fieldwork was conducted over a period of approximately 2 years (October 2016 – November 2018).  The initial phase comprised drinking water sampling at three nearby residences, identified as having shallow drinking water wells (shallow wells, those not installed in a deep aquifer, beneath a protective clay layer, are at risk from surficial contamination).  The three homeowners were contacted in October 2016; two allowed the Navy to sample their wells and one homeowner declined.  Sampling of the two private drinking water wells occurred immediately following.  Neither sample contained PFOS, PFOA, or PFBS, the three PFAS the samples were analyzed for.

Once drinking water was eliminated as a potential risk, the Navy initiated the investigation of environmental media at the park. The initial phase of the investigation was designed to answer three questions: 1) is PFAS present in environmental media at the park; 2) is there any risk to users of the park; and 3) are PFAS migrating offsite.

The effort, conducted from November 2016 to January 2017, included collecting an analyzing for PFAS: co-located surface and subsurface soil samples were collected from 12 locations; grab groundwater samples were collected from 35 locations, two depths at most locations; co-located sediment and surface water samples were collected from 4 locations.

The results, provided to MDE and the Anne Arundel County Bureau of Environmental Health in a letter report dated March 20, 2017, indicated that PFAS were present in all environmental media, including the sediment and surface water of the small tributary of the Little Magothy River, immediately north of the park. Additionally, the report documented that there was no risk to park users. It was noted that drinking water at the park is supplied by the county and there is no direct access to groundwater. For soil the report stated:

"For PFOS, the contaminant present at the highest concentrations, a residential screening value of 1.3 mg/kg was estimated, an order of magnitude higher than the highest detection. This value was derived using the May 2016 United States Environmental Protection Agency (USEPA) Regional Screening Level (RSL) Calculator (https://epa-prgs.ornl.gov/cgi-bin/chemicals/csl_search); a target hazard quotient of 1; default residential exposure assumptions provided by USEPA in the RSL calculator; and the chronic reference dose (RfD) of 2x10-05 mg/kg-day (as published in Drinking Water Health Advisory for Perfluorooctane Sulfonate (PFOS), EPA 822-R-16-004; May 2016).  Further, it should be noted that the residential screening calculation utilizes very conservative exposure parameters, relative to the actual exposure scenario of any park user."

In summary, the concentrations of PFAS in soils are far below that which present a risk to users of Bay Head Park.

The next two phases of the investigation were conducted from September 2018 to November 2018 focused on possible PFAS impacts to the tributary of the Little Magothy River and the river itself from the former Bay Head Road Annex. The first effort employed an imaging survey intended to identify preferred pathways for groundwater-to-surface water discharge, which was used to focus PFAS sampling. The second effort, the PFAS sampling itself was intended to determine to what extent PFAS exists in surface water and sediment, accessible to recreational users of the river. The sampling was also intended to identify potential ecological risk from the three PFAS compounds PFOS, PFOA, and PFBS.

The PFAS sampling included recollecting the 5 co-located sediment and surface water samples at the previously sampled locations in the tributary to assess possible seasonal variability in concentrations; collecting co-located sediment and surface water samples at 3 additional locations along the tributary, based on the presence of seeps identified during the imaging survey; collecting 16 co-located sediment and surface water samples at approximately 100-foot intervals along the shoreline of the Little Magothy River; and recollecting co-located sediment and surface water samples at all 24 locations during the low tidal stage and collecting an additional round of surface water samples only at the high tidal stage at most locations to assess tidal variability.

The four phases of investigation, together comprise the RI. The results were published in the Draft Final Phase I Remedial Investigation (RI) Report, Former Burn Pad Former Bay Head Road Annex, Annapolis, Maryland, March 2020. The results are summarized in Section 7 of the report and concludes with the following recommendation:

"The only potentially unacceptable risk identified was for a hypothetical future resident, consuming groundwater as daily drinking water. Future actions are warranted to supplement the data generated and analyzed in this investigation, in particular for groundwater that was determined to be impacted due to historic releases in the former Burn Pad Area at the Site."

"Additional investigation activities will refine the CSM, including defining the nature and extent of PFAS groundwater impacts. These activities should include the completion of additional sampling of on- and offsite groundwater through temporary or permanent (monitoring wells) sampling points. Following completion of the additional activities, in accordance with the CERCLA process, the CSM and risk assessment will be updated as part
of a RI Addendum."

In summary, there are no identified current risks to users (site workers or recreational users) of either Bay Head Park (exposure to soil) or recreational users of the Little Magothy River (exposure to surface water and sediment). However, the Navy will continue to investigate PFAS impacts, including any necessary revisions to the risk assessment, and will provide updates to our regulatory partner, MDE, the County Bureau of Environmental Health, and the public via finalized reports, this website, and future public meetings.

 

 

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