NAVAL AIR DEVELOPMENT CENTER (8 WASTE AREAS)
WARMINSTER TOWNSHIP, PA
On this page:
- What Is Being Done to Clean Up the Site?
- What Is the Current Site Status?
- EPA’s Involvement at the Site
- Emergency Response and Removal
- Operable Units (opens new page)
- Cleanup Progress (opens new page)
The Naval Air Development Center site in Warminster Township and Ivyland Borough, Bucks County, PA, covers 840 acres and was renamed Naval Air Warfare Center (NAWC) in 1993. Commissioned in 1944, NAWC's main function was the research, development and testing of Naval aircraft systems. Wastes were generated during aircraft maintenance and repair, pest control, firefighting training, machine and plating shop operations, spray painting, and various materials research and testing activities in laboratories. These wastes include paints, solvents, sludges from industrial wastewater treatment, and waste oils. Pursuant to BRAC, NAWC ceased operations in September 1996. Most of the property has been transferred to the private sector. NAWC is located in a populated suburban area and is surrounded by homes, commercial and industrial activities and a golf course. NAWC was placed on the CERCLA NPL due to the threat posed by eight disposal areas to groundwater quality. Prior to the discovery of PFC contamination during the 2012 Five Year Review, the primary groundwater contaminants of concern at NAWC have been found to be trichloroethylene (TCE), tetrachloroethylene (PCE) and carbon tetrachloride. The area surrounding NAWC is completely dependent on groundwater for both public and private water supplies.
PFCs, mainly Perfluoroctanoic Acid (PFOA) and Perfluorooctane Sulfonate (PFOS), were first tested for as emerging contaminants in preparation for the 2012 Five Year Review. During this time, it was discovered that levels in groundwater on the former Navy property exceeded EPA provisional health advisory levels (HALs) for drinking water. Provisional HALs serve as informal technical guidance designed to assist federal, state and local officials in evaluating threats to local water supplies. Provisional HALs are not federally enforceable standards and are subject to change as new information becomes available.
Outside of the CERCLA Five Year Review, in 2013, the EPA required many public water
systems, including the Warminster Township Municipal Authority (WTMA), the local public water supplies in the area of NAWC, to sample for a group of 28 unregulated contaminants, including PFOS and PFOA. Based on the results, two public drinking water production wells impacted by PFOS and PFOA were taken off-line in June 2014.
What Is Being Done to Clean Up the Site?
- EPA has conducted several five-year reviews of the site’s remedy. These reviews ensure that the remedies put in place protect human health and the environment, and function as intended by site decision documents.
- The most recent review concluded that response actions at the site are in accordance with the remedy selected by EPA and that the remedy continues to be protective of human health and the environment in the short term. Continued protectiveness of the remedy requires additional investigation of the vapor intrusion pathway.
What Is the Current Site Status?
- The U.S. Navy in conjunction with EPA is currently investigating perfluorinated chemicals (PFCs) in groundwater both on the former Navy property and at nearby residential wells.
- More than 200 residential wells have been tested and the Navy is working with local muncipalites and Water Authorities to connect residents with well contamination to the public water system.
- In addition, groundwater remedies for volatile organic compound (VOC) contamination, which include pumping and treatment of groundwater in three areas, have been demonstrated by the Navy to be operating properly and successfully.
- The majority of the former Navy property has been transferred to the private sector per the Base Realignment and Closure Act.
EPA’s Involvement at the Site
- This site is being addressed through Federal actions. The site was listed on EPA's National Priorities List on October 4, 1989 making it eleigible for long-erm investigation and cleanup.
- All remedial construction is complete. All remedies for contaminated soil are in place. Remedies for contaminated groundwater are operating properly and successfully.
- In response to TCE and PCE contamination detected in off-base private wells adjacent to NAWC, in 1993, the Navy installed water treatment systems in over 40 homes and subsequently connected over 20 homes to public water systems.
- Since sampling results suggested that the contamination was due to both NAWC and an unknown off-base source, the EPA connected an additional 40 residences to a public water system in 1994.
- In 1995, a commercial facility was also connected to public water by the Navy.
- In 1996, the construction of an on-base groundwater treatment system was completed and the pumping and treatment of PCE-contaminated groundwater at Area C at NAWC was initiated.
- The construction of groundwater extraction wells in Areas A and D at NAWC was initiated in late 1998 and early 1999, respectively.
- Pumping and treatment of contaminated groundwater in Area A was initiated in Summer 1999.
- The primary contaminants at Area A are TCE, carbon tetrachloride and PCE; at Area D, the contaminant is TCE.
- In 1996, a removal action at Site 4 excavated and removed waste from a series eight disposal trenches. The primary contaminants in the waste were polychlorinated biphenyls (PCBs).
- In 1997, a removal action was conducted at Sites 6 and 7, a series of disposal trenches and pits.
- Contaminants in soil/waste excavated and removed from Sites 6/7 included TCE, PCE, and PCBs.
- In 1998, soil contaminated with cadmium, lead and other heavy metals was excavated and removed as part of a removal action at Sites 1 and 2.
- In 1999, soil contaminated with lead was removed from Site 8.
- Access to remaining soils of concern at Sites 1, 2, 6 and 7 will be controlled through deed restrictions.
- Erosion controls are in place at Site 2 and a clean, vegetated soil cover in place at Sites 6 and 7. Monitoring of stream sediment is ongoing.
- The Navy has completed its third five-year review. EPA policy towards potential risk from vapor intrusion has changed since the last five year review and it is anticipated that the Navy will complete additional vapor intrusion sampling to insure that all remedies in place are protective of human health and the environment.
- In addition, the Navy is developing a work plan for an optimization study to determine if in-situ treatment would accelerate groundwater remediation.
- In the summer of 2014, at the request of the U.S. Navy, the EPA began sampling private drinking water wells in the area of the former Naval Air Warfare Center (NAWC), Warminster, PA for perfluorinated chemicals (PFCs), including perfluorooctane sulfonate (PFOS) and perfluorooctanoic acid (PFOA).
- Sample results to date indicate that some private drinking water wells have been impacted by PFOS and PFOA above the EPA’s provisional health advisory level (HALs). Those homes are being provided an alternate water supply until an appropriate solution can be implemented.
- The U.S Navy, with input from both the U.S. EPA and PADEP, is currently conducting a remedial investigation to define the nature and extent of PFC contamination and identify possibly sources.
Emergency Response and Removal
- Cleanup has also included several removal actions, or short-term cleanups, to address immediate threats to human health and the environment.
- Between 1993 and 1995, the Navy installed water treatment systems in over 40 homes and subsequently connected over 20 homes and one commercial facility to public water systems.
- EPA connected an additional 40 residences to a public water system in 1994. Between 1996 and 1999, the Navy excavated and removed waste from eight disposal trenches at Site 4, removed soil and waste from disposal trenches and pits at Sites 6 and 7, removed contaminated soil at Sites 1 and 2, and removed lead-contaminated soil from Site 8.
During cleanup, a site can be divided into a number of distinct areas depending on its complexity. These areas, called operable units (OUs), may address geographic areas, specific problems, or areas where a specific action is required. Examples of typical operable units include construction of a groundwater pump and treatment system or construction of a cap over a landfill.