William Dick Lagoons
Current Site Information
EPA Region 3 (Mid-Atlantic)Pennsylvania
West Caln Township
EPA ID# PAD980537773
6th Congressional District
Last Update: December 2012
Current Site StatusThe U.S. Environmental Protection Agency is overseeing the cleanup of the William Dick Lagoons site where (in the 1990s) 115 homes were connected to the public water supply system to ensure them a reliable source of potable water. A groundwater extraction system was installed during the summer of 2000 to further study the groundwater. This resulted in the construction of a groundwater treatment plant that is currently extracting and treating contaminated groundwater at a rate of approximately 25 gallons per minute. Treated groundwater is required to meet the Pennsylvania Department of Environmental Protection NPDES (discharge) standards prior to being discharged to an off-site stream. Soil cleanup activities began in July of 2003. In January and February 2008, confirmation sampling was conducted with results that indicated that the soil had yet to meet the Site cleanup goals. Several individual soil removals were conducted by the PRP from 2009 to the present. A final, confirmation sampling event will be performed when the required excavations are completed. A vapor intrusion evaluation is scheduled to be performed on several properties above the contaminated groundwater plume in 2013.
Site DescriptionThe William Dick Lagoons site, located in Chester County, Pennsylvania, is a 4 ½ acre site. It included three unlined lagoons which were used for waste disposal from the late 1950s to 1970. Chemical Leaman Tank Lines, Inc. (CLTL) cleaned petroleum products, latexes, and resins from its tank trailers, and dumped the final rinse water, and possibly residual chemical product, into the lagoons. The lagoons, about two acres in total area, contained more than four million gallons of wastewater over the years. The lagoons were not adequately diked, and two were breached in 1970, releasing about 300,000 gallons into a small tributary. Site soils are contaminated and are moderately permeable, resulting in the contamination of groundwater. In 1971, a cleanup was conducted by Chemical Leaman, under an agreement with the Pennsylvania Department of Health. Chemical Leaman collected samples from the materials in the lagoons, sprayed the liquid that remained over the adjacent land surface, and filled the remaining lagoon pits with soil. The filled areas were then vegetated. In 1987, the EPA sampled private wells and springs used by local residents and found several to be contaminated with trichloroethylene (TCE). Chemical Leaman subsequently agreed to provide carbon filters to the affected homes. The aquifer is the source of water for private wells serving approximately 1,400 people within three miles of the site. Numerous residential wells surround the site. The nearby Birch Run creek discharges to a water supply reservoir approximately three miles downstream of the site. This reservoir is used as a source of water for more than 15,000 residents of the city of Coatesville. A campground and a trailer park are located within one mile of the site.
Site ResponsibilityThe site is being addressed through federal 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 July 22, 1987.
Threats and ContaminantsThe groundwater is contaminated with TCE, chloroform, other volatile organic compounds (VOCs), and semi-volatile organic compounds (semi-VOCs) from former waste disposal activities. The soil is contaminated with a variety of VOCs, as well as polycyclic aromatic hydrocarbons (PAHs) and pesticides. Drinking contaminated ground water, inhaling VOCs from groundwater, and direct contact with contaminated soil, pose potential health risks. However, as noted under "Current Status" and "Cleanup Progress" the exposure pathways presented by contaminated ground water have been eliminated by the extension of the public water supply line to replace private wells as the primary source of drinking water. Also, some private wells located downgradient of the site, have been equipped with residential (carbon) treatment systems and the Chester County Health Department requires that any new well installations within the contaminated groundwater plume (an "area of concern") also include groundwater sampling for the contaminants of concern that are associated with the William Dick Lagoons Site. The pump and treat system will reduce levels of contamination in ground water, over time, and on-site soil contamination cleanup activities are expected to be completed by 2012.
Contaminant descriptions and risk factors are available from the Agency for Toxic Substances and Disease Registry, an arm of the CDC.
In 1987, EPA signed a consent order with Chemical Leaman Tank Lines (CLTL) that required the installation of a fence around the former lagoon area to prevent direct contact with the contamination remaining in the lagoons. The order also required periodic sampling of home wells near the site and required the installation of carbon filters, if home wells were found to be affected by site contaminants. A total of 136 home wells were monitored and carbon filters were installed on 16 home wells. This action prevented any immediate threat from exposure to the remaining contamination at the site.
Two Records of Decision (RODs) were issued by EPA; in 1991 and 1993. The 1991 ROD required the extension of the public water supply, the performance of a site-wide hydrogeological study, and the implementation of an interim groundwater treatment system. The 1993 ROD specified a soil cleanup plan. A Consent Decree was entered into with CLTL on October 10, 1995. The decree addressed the site clean-up activities required by the two RODs through three distinct activities:
1. Water Line Extension - CLTL agreed to pay $1.6 million to EPA to construct an extension of the public water supply. This extension provides public water to affected and potentially affected residents near the site. The construction of the water line began in April 1998 and was completed in May 1999. Approximately 115 homes near the Site have been connected to the public water supply.
2. Hydrogeologic Study/Interim Groundwater Treatment - CLTL agreed to conduct a pre-design Hydrogeologic Study of the site then design and implement an interim groundwater treatment program. At the completion of the interim system operation, the treatment system's effectiveness will be evaluated and a final plan for long-term groundwater treatment will be specified in another record of decision. EPA approved CLTL's plan for the Hydrogeologic Study on February 25, 1997. Twenty-three additional monitoring wells were installed and all field sampling was completed. The final study report was submitted in January 1999. The extraction well system construction was completed during the fall of 2000. After evaluating a number of discharge options, it was determined the best discharge option for the interim groundwater treatment system is to discharge treated groundwater to Birch Run creek. The design was approved by EPA in April 2006 and construction of the groundwater extraction and treatment system was completed in 2008. The groundwater treatment system is expected to be operating full time by the end of 2011.
3. On-Site Treatment of Contaminated Soil - CLTL agreed to design and implement a soil cleanup remedy that would utilize a combination of thermal desorption and soil vapor extraction/ biodegradation (SVE/BIO) treatment technologies. Most of the overlying soils and remaining sludge material have been cleaned using thermal desorption treatment. Contaminated soils that were too heavily contaminated to be treated by the thermal desorption system were shipped off-site to a permitted treatment/disposal facility. CLTL's contractor attempted to clean the remaining soils utilizing a SVE/BIO system. However, after 18-months of operation, soil samples showed that the SVE/BIO system failed to adequately clean the soils. CLTL (now known as QDI) has excavated select contaminated soils from two heavily contaminated areas of the site and stockpiled these soils (currently covered) on the south side of the site. An in-situ chemical oxidation pilot test has been implemented with favorable results. Any proposed change in soil treatment technology would require EPA approval prior to implementation.
A vapor intrusion evaluation is scheduled to be performed on several properties above the contaminated groundwater plume in 2013.