NAVAL STATION MAYPORT

On April 26, 2024, the United States Environmental Protection Agency (EPA) published a National Primary Drinking Water Regulation (NPDWR) establishing nationwide drinking water standards for certain PFAS under the Safe Drinking Water Act. The regulation applies to public drinking water systems. Operators of public drinking water systems regulated by the NPDWR have until April 26, 2029 to meet these standards. In September 2024, the Department of War (DoW) published “Prioritization of Department of Defense Cleanup Actions to Implement the Federal Drinking Water Standards for Per- and Polyfluoroalkyl Substances under the Defense Environmental Restoration Program,” which describes the DOW’s plans to incorporate the EPA’s drinking water regulation into DoW’s ongoing PFAS cleanups and prioritize actions to address private drinking water wells with the highest levels of PFAS from DoW activities. Table 1 shows the DoW PFAS Interim Action Levels for Private Drinking Water Wells and EPA NPDWR Levels.

The National Defense Authorization Act (NDAA) for 2026 was signed into law on December 18, 2025. This allows the Navy to offer interim actions (such as connection to public drinking water or a treatment system) for downgradient households in the community that receive water from private drinking water wells where levels of perfluorooctanoic acid (PFOA) and/or perfluorooctane sulfonic acid (PFOS) exceed the EPA NPDWR Levels. As of that date, at least one home in the community qualified for alternative drinking water from the Navy as a result of a PFAS release at NAVSTA Mayport.

Table 1 presents the DoW PFAS Interim Action Levels for Private Drinking Water Wells (DoW 2024) and EPA NPDWR Levels. The DoW’s September 2024 memorandum can be found here.

Table 1: EPA NPDWR Levels for Public Water Systems and DoW PFAS Interim Action Levels for Private Drinking Water Wells

ppt = part(s) per trillion

¹ These levels are based on current EPA NPDWR levels. If EPA updates applicable requirements, DoW will review and update its policy as appropriate.

PRIVATE DRINKING WATER WELL SAMPLING NEAR NAVSTA MAYPORT

Certain PFAS have been detected in groundwater at NAVSTA Mayport and in private drinking water wells above the DoW PFAS Interim Action Levels for Private Drinking Water Wells. As a result of the detections at NAVSTA Mayport, sampling areas (Figure 2) were established 1 mile in the direction that groundwater flows away from the locations of these detections and subsequently expanded based on results for private drinking water wells sampled in those areas.

2026 PRIVATE DRINKING WATER WELL SAMPLING

At this time, the Navy is requesting property owner permission to sample private drinking water wells in the sampling areas near NAVSTA Mayport (Figure 2). Considering the levels in Table 1, the Navy has determined that the private drinking water well sampling area near NAVSTA Mayport should be expanded. Due to improvements in laboratory methods, the Navy is also requesting property owner permission to resample private drinking water wells that were sampled by the Navy in 2019. If your drinking water is provided by Jacksonville Electric Authority or the City of Atlantic Beach, the Navy does not need to sample your drinking water.

The samples will be sent to an accredited, independent laboratory. The laboratory will analyze for the presence of certain PFAS according to EPA-approved methods. The laboratory will then provide the Navy with preliminary results, after which the preliminary results will be validated by an independent third-party for quality assurance. Once the results are validated, they will be provided to property owners and tenants, approximately 3 months after sampling.

Figure 2 - Sampling Areas

PREVIOUS 2019 PRIVATE DRINKING WATER WELL SAMPLING

In 2019, the Navy sampled private drinking water wells based on information that was available at that time about PFAS releases at NAVSTA Mayport. The 2019 sampling area, shown in Figure 2, was established 1 mile in the direction that groundwater flows away from a known PFAS release area. Table 2 provides a summary of the results of the 2019 sampling. No properties had detections of PFOA and/or PFOS above 70 ppt, the Navy’s action level at the time. Table 3 presents the PFAS results.

Table 2: NAVSTA Mayport – 2018 Private Drinking Water Well Results Summary

*70 ppt for PFOA and PFOS, individually or combined, was the Navy’s action level at the time of this sampling.

The Navy has re-evaluated the 2019 private drinking water well results. Based on this information, the Navy has determined that private drinking water wells sampled near NAVSTA Mayport contain PFAS at or above the DoW PFAS Interim Action Levels for Private Drinking Water Wells (Table 1). The Navy is requesting property owner permission to implement interim actions to address PFAS in drinking water at the locations where PFAS exceeds the DoW PFAS Interim Action Level for Private Drinking Water Wells (Table 2). The Navy will also offer to implement interim actions at locations where PFOA and/or PFOS exceed the EPA NPDWR Levels.

Table 3: NAVSTA Mayport – 2019 - Private Drinking Water Well Results

ACTIONS BASED ON PRIVATE DRINKING WATER SAMPLING RESULTS

The preliminary results from the private drinking water well sampling are expected approximately 30 days after collecting the samples. The Navy will provide notification to the property owners and tenants of their drinking water results and any follow-up actions, if needed.

The Navy will address PFAS in private drinking water wells in keeping with the DoW policies and the 2026 NDAA:

PFAS at or above the DoW PFAS Interim Action Levels for Private Drinking Water Wells (Table 1). The Navy will work with property owners to implement an enduring solution as soon as possible. Options for enduring solutions may include connection to public water or installation of a drinking water treatment system. For any drinking water wells with PFOA and PFOS, individually or combined, above 70 ppt, the Navy can provide bottled water for drinking and cooking to property owners or tenants until a more enduring solution is implemented.

PFOA and/or PFOS at or above the EPA NPDWR Levels (Table 1). Where PFOS and/or PFOA levels in private drinking water exceed the EPA NPDWR Levels due solely to Navy activities on its installation, the Navy will offer an enduring drinking water solution as soon as possible.

For final remedial actions, the Navy will address PFAS in private drinking water wells down to EPA NPDWR Levels or background levels in accordance with Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) requirements.

IDENTIFICATION OF PFAS RELEASES AT NAVSTA MAYPORT

The Navy finalized a PFAS Preliminary Assessment (PA) in 2021 that identified areas where releases of PFAS may have occurred. Based on the results of the PFAS PA, the Navy completed a PFAS Site Inspection (SI). Sample collection and analyses of soil and groundwater were conducted from March to April 2021. PFAS were found in groundwater and soil at NAVSTA Mayport. The PFAS release areas investigated at NAVSTA Mayport are listed below and shown on Figure 3. Remedial investigations are ongoing at the following release areas:

• Public Works Transportation
• Recycling Center (formerly the Defense Reutilization and Marketing Office [DRMO])
• Hangar 1343
• Lift Station 1349
• Hangar 1552
• Old Firefighting Training Area (FFTA)
• Hazardous Material (HAZMAT) Center
• Fire Department Crash Station (Building 1607)
• WWTP
• Oily Waste/Waste Oil (OWWO) Treatment Plant
• Air Sparging Hydrocyclone (ASH) Unit Release
• Flightline Retention Ponds
• NAVSTA Mayport Turning Basin
• Foxtrot Wharf AFFF Release
• Charlie Pier AFFF Release
• Operational Training Center (Building 1555)
• Old Landfills (SWMUs 2, 3, 4, and 5)
• Carbonaceous Fuel Boiler Building (SWMU 17)
• Hazardous Waste Storage Facility with Fire Suppression System
• Dredge Material Berm and Sediment CDFs
• Runway
• Fleet Training Center (FTC) FFTA

The Navy will continue investigating PFAS at NAVSTA Mayport following the CERCLA process and will evaluate if actions are needed. To find out more about all of the environmental investigations at NAVSTA Mayport, visit https://www.navfac.navy.mil/Mayport.

Figure 3 - PFAS Release Areas at NAVSTA Mayport

NAVSTA MAYPORT PRIVATE DRINKING WATER WELL SAMPLING DOCUMENTS - CURRENT INVESTIGATION

• 2026 Private Drinking Water Well Sampling Fact Sheet

• 2026 Private Drinking Water Well Sampling Notification Letter

• 2026 Private Drinking Water Well Resampling Initial Notification Letter

• 2026 Drinking Water Well Questionnaire

• 2026 Permission to Access Property Agreement for Sampling of Drinking Water Well(s)

• 2026 Frequently Asked Questions - Drinking Water Sampling for PFAS

• 2026 Addressing PFAS In Private Drinking Water Wells Notification Letter

• 2026 Access Agreement for Treatment System Installation and Monitoring

• 2026 Postcard to Tenants – Sampling Requested

• 2026 Postcard to Owners and Tenants – Sampling Assumed Not Required

• 2026 Postcard to Owners – Sampling Reminder

• 2026 Postcard to Tenants – Addressing PFAS

• 2026 Postcard to Owners – Addressing PFAS Reminder

• 2026 POC Card

NAVSTA MAYPORT PRIVATE DRINKING WATER WELL SAMPLING DOCUMENTS - PREVIOUS INVESTIGATIONS

• 2019 Open House Posters

• August 2019 Drinking Water Investigation Fact Sheet

ADDITIONAL DOCUMENTS

• ATSDR - PFAS Overview

• ATSDR - PFAS Health Effects

• ATSDR - Breastfeeding and PFAS

LINKS

• DoW PFAS website

• EPA PFAS website

• ATSDR PFAS website