North Penn Area 12
Current Site Information
EPA Region 3 (Mid-Atlantic)Pennsylvania
EPA ID# PAD057152365
6th Congressional District
Last Update: February 2014
Current Site Status
The U.S. Environmental Protection Agency (EPA) oversaw construction related to cleanup activity at this site. All construction activities are now complete. A 5½ mile extension to the existing public water supply system was constructed, and 147 homes and businesses were connected to the public water system.
A groundwater extraction and treatment system was also constructed and is now operational. Long-term monitoring will be conducted to evaluate the performance of the groundwater treatment system and to ensure that homes beyond the extent of the new water system are not adversely affected by groundwater contamination from the site.
A Five-Year Review completed on August 31, 2005 concluded that the remedy is currently protective of human health and the environment.
On June 20, 2007 EPA approved a proposal by the responsible parties to enhance the groundwater extraction and treatment system by installing an additional extraction well on an adjacent property. This well was completed and placed into operation in November of 2007.
The second Five-Year Review was completed on September 28, 2010 and the protectiveness determination was deferred until a vapor intrusion assessment was completed for the Site. The vapor intrusion assessment was completed in October of 2012 and determined that vapor intrusion is not a concern at the Site. The results of the assessment were documented in a Five-Year Review Addendum completed in September 2012, which included an updated protectiveness statement indicating that the Site is currently protective of human health and the environment.
The Five-Year Review Addendum also documents the construction of three new monitoring wells in September 2012 to help determine the effectiveness of the new extraction well and better delineate the plume. The System Effectiveness Evaluation Report was submitted to EPA in 2013 following a year of sampling with the new wells.
The North Penn Area 12 site includes the former Transicoil facility and the adjacent former control facility for a Nike Missile Base on Trooper Road in Worcester Township, Montgomery County, Pennsylvania. Between 1952 and 1991, several different owners have manufactured electric motors at the 25-acre former Transicoil facility. State records show that the facility used several drums of trichloroethylene (TCE) each year as a degreasing solvent until 1976, when it switched to trichloroethane. The company stored waste oil and solvents in an underground tank, and allegedly disposed of spent solvents in the septic system and directly on the ground. In 1979, the State found elevated concentrations of solvent-based chemicals in on-site wells and in private off-site wells. Subsequent sampling by a consultant to Transicoil confirmed the results.
The North Penn Area 12 Site also includes the 12-acre former Nike missile control facility that was located adjacent to the Transicoil property and operated by the U.S. Army. The former Nike control facility property was used by the Army from 1954 to 1968. TCE was allegedly used and disposed of at the former Nike control facility property between 1954 and 1968.
The area surrounding the site is primarily rural, interspersed with agricultural activities and housing developments. Approximately 16,200 people live within a three-mile radius of the site and use groundwater as a drinking water supply. The closest residence is 600 feet from the site. Schools and hospitals are also located nearby.
Site ResponsibilityThis site is being addressed through a combination of federal, state, and potentially responsible parties' actions.
NPL Listing HistoryOur country's most serious, uncontrolled, or abandoned hazardous waste sites can be cleaned using federal money. To be eligible for federal cleanup money, a site must be put on the National Priorities List. This site was proposed to the list on January 22, 1987 and formally added to the list on February 21, 1990.
Threats and ContaminantsGroundwater contains volatile organic compounds (VOCs) including TCE from alleged solvent waste disposal. There is a potential health threat from direct contact with and/or ingestion of contaminated drinking water. As a follow-up to the 2010 Five-Year Review, a possible vapor intrusion pathway from VOCs in the groundwater was investigated and determined that vapor intrusion is not a concern at the Site.
Contaminant descriptions and risk factors are available from the Agency for Toxic Substances and Disease Registry, an arm of the CDC.
An underground waste solvent tank, thought to be a potential source of contamination, was removed by a former owner/operator of the site. Under terms of a 1990 order and subsequent bankruptcy settlement, Eagle-Picher/Transicoil, a responsible party for the site, provided carbon filters and periodic sampling for 13 affected residential wells near the site. Well sampling conducted in January 1995 identified several additional residential wells that had been affected by site contamination. In August of 1995, EPA issued a unilateral administrative order to several other responsible parties for the site that required continuous periodic sampling and the installation of carbon filter systems on additional home wells found to be affected by site contamination. Approximately 30 homes were provided with carbon filters under the terms of the two orders. These actions prevented any immediate health threat from site-related contamination.
In 1990, Eagle-Picher/Transicoil, under terms of an order, began an investigation to determine the nature and extent of the contamination from the site. Eagle-Picher/Transicoil filed for bankruptcy during the field activity stage of the study in 1991. Therefore, EPA completed this study. EPA issued a cleanup plan on September 30, 1997 which specified the long-term remedial measures for the site. On July 22, 1998, EPA issued an order to the responsible parties to complete the design and implement the cleanup as specified in the cleanup plan. An extension of the public water supply system has been completed. Wells to 147 homes and businesses have been replaced with public water connections. A groundwater treatment system was also constructed and began operation in September 2000. The groundwater treatment system was adjusted in 2007 with the construction of an additional extraction well. Three new monitoring wells were constructed in October of 2012 in order to help assess the effectiveness of this optimization to the system and better delineate the plume. The conclusions of the effectiveness of the optimization will be documented in an Optimization Report in the Fall of 2013, following a year of sampling using the new wells.
Long-term monitoring will evaluate the performance of the groundwater treatment system and ensure that homes beyond the extent of the new water system are not adversely affected by groundwater contamination from the site. Monitoring will continue until site-related groundwater contaminants are reduced to acceptable levels.
A vapor intrusion assessment was completed in 2012 and determined that vapor intrusion is not currently a concern at the Site. The results of the assessment were documented in the 2012 Five-Year Review Addendum for the Site, which included an updated protectiveness statement indicating that the Site is currently protective of human health and the environment.