In March 2023 the Navy sampled drinking water wells near Naval Support Facility (NSF) Thurmont to test for certain per- and polyfluoroalkyl substances, commonly known as PFAS. For questions about this sampling, please contact the Naval District Washington Public Affairs Office at 202-433-2678 or NDW_publicaffairs@us.navy.mil.
Per- and polyfluoroalkyl substances (PFAS) are a family of thousands of different chemicals that have been widely used in industrial and consumer products since the 1950s. PFAS are man-made and have been used in many household and industrial products because of their stain- and water-repellent properties. PFAS are now present virtually everywhere in the world. Once these compounds are released, they break down very slowly.
In May 2016, the United States Environmental Protection Agency (EPA) issued lifetime drinking water health advisories of 70 parts per trillion (ppt), individually or combined, for two commonly used and studied PFAS, perfluorooctanoic acid (PFOA) and perfluorooctane sulfonate (PFOS). Health advisories are not enforceable, and are not regulatory levels; rather, they are levels that provide Americans, including sensitive populations, with a margin of protection from a lifetime of exposure.
In June 2016 the Department of the Navy developed a proactive policy to ensure the communities near Navy installations are not exposed to drinking water with PFOA and/or PFOS because of a known or potential Navy release of PFAS-containing materials. The Navy’s first priority with the investigations of past releases is to ensure that concentrations of PFOA or PFOS in drinking water are not above 70 ppt as a result of a Navy PFAS release. The most common activity that could have resulted in the historical release of PFOA, PFOS, and other PFAS to the environment at Navy installations is the use of firefighting foam (specifically, aqueous film-forming foam, or AFFF) for testing, training, firefighting, and other life-saving emergency responses. Because of this historical use, there is potential for PFOA, PFOS, and other PFAS to be in the groundwater on base, and also be present in nearby drinking water wells that are located in the direction that the groundwater flows away from the base.
In January 2023, the Department of Defense released a new military specification for a formulation of firefighting foam. Until products that meet this new military specification are available, the Navy will continue to use formulations that contain lower concentrations of PFOA and PFOS than many historical AFFF formulations and will continue to take steps to prevent or minimize additional release of firefighting foam to the environment.
On March 14, 2023, the EPA proposed a draft regulatory drinking water standard for certain PFAS, including PFOA and PFOS. In response, the DoD has issued the following statement: "DoD respects and values the public comment process on this proposed nationwide drinking water rule and looks forward to the clarity that a final regulatory drinking water standard for PFAS will provide. In anticipation of the final standard that EPA expects to publish by the end of 2023, the DoD is assessing what actions DoD can take to be prepared to incorporate EPA’s final regulatory standard into our current cleanup process, such as reviewing our existing data and conducting additional sampling where necessary. In addition, DoD will incorporate nationwide PFAS cleanup guidance, issued by EPA and applicable to all owners and operators under the federal cleanup law, as to when to provide alternate water when PFAS are present."
Off-Base Drinking Water Sampling at NSF Thurmont (Figure 1)
When a known or suspected release of PFAS is identified on a Navy installation and groundwater or surface water is used as drinking water near the installation, a sampling area is established 1 mile in the direction that groundwater flows away from a release area. The Navy offers sampling to all property owners and tenants whose property is within the sampling area and whose drinking water is supplied by groundwater or surface water.
Figure 1: Sampling Area
Actions Based on Off-Base Drinking Water Sampling Results
The preliminary results from the off-base drinking water sampling are expected approximately 30 days after collecting the samples. The Navy notifies the property owners and tenants of their drinking water results and any follow-up actions, if needed. The Navy will do its best to keep the testing results and property information confidential to the extent permitted by law.
The Navy provides bottled water for drinking and cooking to any property in the sampling area with drinking water that contains PFOA and/or PFOS above 70 ppt and does not have an alternate drinking water source available. The Navy will continue to provide bottled water until a permanent solution is implemented.
2023 Off-Base Drinking Water Sampling Results
In March 2023, the Navy initiated the sampling of drinking water from wells within the sampling area. Table 1 summarizes the drinking water sampling results to date, and Table 2 presents the PFOA, PFOS, and summed PFOA + PFOS results for each sample. The Navy called each property owner and tenant upon receipt of their preliminary results to let them know if their water contains PFOS and/or PFOA above or below 70 ppt. Final laboratory results were mailed to each property owner and tenant after all data were verified and final. Out of respect for the privacy of the property owners and tenants, individual results are provided only to each property owner and tenant.
Table 2. NSF Thurmont – Off-Base Drinking Water Summary of Detections as of June 30, 2023
|Table 1. NSF Thurmont - Off-Base Drinking Water Results as of June 30, 2023
|Number of Drinking Water Samples
||Number of samples with no detections of PFOA or PFOS
||Number of samples with detections of PFOA and/or PFOS below 70 ppt
||Number of samples with detections of PFOA and/or PFOS above 70 ppt
Identification of PFAS Releases at NSF Thurmont
In 2021, a comprehensive PFAS Preliminary Assessment was initiated, which identified the following areas where releases of PFAS-containing materials may have occurred.
As of June 2023, a Site Inspection of groundwater and soil at these two areas is ongoing.
NSF Thurmont Drinking Water Sampling Documents