BUCKS COUNTY, PENNSYLVANIA
The Boarhead Farms site currently does not pose a public health threat to on-site or off-site
residents. One on-site dwelling uses a shallow (60 feet deep) private well that contains
trichloroethene at levels exceeding the Environmental Protection Agency's (EPA) drinking water
standards. EPA placed a whole-house carbon filtration unit on the water supply to ensure that
residents are not exposed to the trichloroethene present in the well water. The site is currently
undergoing further remediation, which will prevent any likelihood of future exposure to site contaminants.
EPA Region III requested the Agency for Toxic Substances and Disease Registry (ATSDR) to review residential well water data collected near the site to determine if site-related contaminants migrating through groundwater pose a public health threat to local citizens. ATSDR and the Pennsylvania Department of Health (PADOH) reviewed well water data collected January 1993 through December 1996. Additionally, we reviewed previously written public health reports and remedial investigation reports describing site geology, hydrogeology, and past waste disposal practices (1, 2, 3).
The Boarhead Farms site is on about 120 acres of land on Lonely Cottage Road in Upper Black Eddy, Bridgeton Township, Bucks County, Pennsylvania. Boarhead Corporation purchased the site in 1969. Boarhead Corporation remains the current legal owner of the site, but Keystone Excavation Company leases part of the site for its operations (Figures 1, 2, and 3). One home is on the site and is served by a private well.
In the 1970s, the site was used as an unpermitted dumping ground for a variety of wastes. Today, after EPA removed more than 2,500 drums under an interim removal action, a groundwater treatment facility is nearly complete (Figures 4 and 5). The Feasibility Study Report (4) comprehensively describes alternatives for other remedial work such as soil aeration. An interception trench was completed October 8, 1997, that is expected to stop further migration of contaminants in groundwater.
Additionally, several natural conditions at the site fortuitously limit the migration of contaminants to off-site wells.
- The site is underlain by diabase, a relatively massive (unfractured) igneous rock of low permeability that retards downward movement of groundwater and keeps most contamination shallow (within 20 feet of the surface). Diabase outcrops are abundant throughout the site area.
- Low gradients (wetlands) for surface water and groundwater near Lonely Cottage Road (Figures 3 and 6) further retard or prevent off-site movement of contaminants.
- A groundwater divide parallel to the entrance road and approximately coinciding with Birch Road (Figures 6, 7, and 8) diverts groundwater as shown in Figure 6 and helps protect wells east of Lonely Cottage Road. That feature (divide) partly explains the "clean" areas in Figures 7 and 8.
On March 19, 1997, J.E. Godfrey of PADOH visited the site and met with the EPA Remedial Project Manager (RPM). The RPM conducted a tour of the site and nearby residential areas. We visited one home equipped with an EPA-supplied water treatment system (carbon filter unit). Presumably the unit was installed as a precautionary measure against possible future off-site migration of volatile compounds. Well water data have not shown the presence of site contaminants in the well water at levels of health concern (Table 1). In addition to the off-site home, EPA installed a carbon filter water treatment unit at the on-site residence on October 15, 1997. The well water at that home contained levels of trichloroethene greater than the Maximum Contaminant Level established for public drinking water supplies. EPA plans to remove more drums from the site and to continue remediation.