Mid-Atlantic Superfund

EPA Region 3 (Mid-Atlantic)

Delaware
New Castle County
2 wiles west of Delaware City

EPA ID# DED980551667

1st Congressional District

Last Update: January 2009

Other Names

None

Current Site Status

In the early 1990s, the U. S. Environmental Protection Agency (EPA) oversaw the construction of a groundwater pump and treat system, which has been operational since January of 1991. That system is treating over 400,000 gallons of water per day and the size of the original contaminant plume has been steadily decreasing over time. In 1992, a second plume of groundwater contamination was discovered. To contain the second plume, additional extraction wells and piping were installed and completed in 2001. EPA continues to monitor this modified collection system and oversee annual sampling events conducted by the potentially responsible parties (PRPs).

In February 2004 routine sampling near the site uncovered levels of a ground water contaminant found at the site in a nearby well at levels above accepted drinking water standards. This contaminant may or may notbe associated with the site itself. EPA, the Delaware Department of Health and Social Services, Office of Drinking Water (ODW), the Delaware Department of Natural Resources and Environmental Control (DNREC), and the PRPs are currently investigating the presence of this contaminant under EPA oversight. Users of the well in question have been supplied with bottled water since April 2004 and other nearby residential wells have been sampled quarterly to insure that no one is exposed to contaminated ground water. Arrangements to provide for extension of and connection to the municipal water supply for the businesses and residences whose wells were contaminated was agreed to by the PRPs in 2007. This work will be conducted voluntarily by the site PRPs under EPA, DNREC and DE ODW oversight and should be completed in early 2009. The Site's third Five-Year review is planned for later this year.

Site Description

The 200-acre Delaware City PVC Plant, located in Delaware City, Delaware, consists of a polyvinyl chloride (PVC) manufacturing facility owned and operated by Formosa Plastics Corporation of Delaware. The manufacturing facility was built in 1966 by Stauffer Chemical Company. During early plant operations, earthen lagoons were used to dump waste PVC. Another area of the property was used to bury off-grade PVC sludge. Groundwater under the site has been heavily contaminated with solvent chemicals, trichloroethylene, 1,2-dichloroethane, and vinyl chloride. The contaminated aquifer is used locally as a source of drinking water in local residences and businesses, and for agricultural purposes. Approximately 50 people live within one mile of the site. When local residential and commercial wells were found to be contaminated, alternate water supplies were promptly provided by the PRPs. At present, arrangements to provide for extension of and connection to the municipal water supply for the businesses and residences whose wells were contaminated is underway and should be completed in early 2009.

Site Responsibility

Cleanup of this site is the responsibility of federal and state governments, and parties potentially responsible for site contamination.

NPL Listing History

Our 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 December 30, 1982 and formally added to the list September 8, 1983.

Threats and Contaminants

Groundwater under the site has been heavily contaminated with trichloroethylene, 1,2-dichloroethane, and vinyl chloride, chemical components of solvents and degreasers.

Contaminant descriptions and associated risk factors are available at: (ATSDR web site).

 

Cleanup Progress

EPA entered into an agreement with Formosa Plastics Corp. of Delaware and Stauffer Chemical Company in 1984. Under this agreement, they agreed to conduct an evaluation of cleanup alternatives for the site, to recommend cleanup options, and to submit plans to carry out these options. In September of 1986, EPA signed a Record of Decision (ROD) for the site which states that the site is 260 acres. During remedial action the groundwater plume was found to extend further so the site is approximately 400 acres in size. The cleanup included pumping and treating contaminated groundwater, excavating off-grade materials and contaminated soil for off-site disposal, and properly capping the buried sludge pits. The original agreement was amended in May of 1987 to include the requirements of the ROD. The groundwater pump and treat system, which has been operational since January of 1991, treats over 400,000 gallons of water per day. The size of the original contaminant plume has been steadily decreasing over time because of the groundwater pump and treat system. In 1992, a second plume of groundwater contamination was discovered. To contain the second plume, additional extraction wells and piping were installed and completed in 2001. The plumes of contaminated ground water have been shrinking year-by-year, and EPA continues to oversee the PRP-sponsored remedial action.

In February 2004 routine sampling of a drinking water well at a facility near the site uncovered concentrations of a ground water contaminant found at the site (1,2 dichloroethane; a.k.a. ethylene dichloride) at levels above accepted drinking water standards. This contaminant may or may not be associated with the site. EPA, the Delaware Department of Health and Social Services, Office of Drinking Water (DE ODW), the Delaware Department of Natural Resources and Environmental Control (DNREC) and the PRPs have been investigating this exceedance. The facility and other nearby ground water wells were sampled by DNREC, ODW and the PRPs under EPA oversight on May 12, 2004. In addition, DNREC has conducted separate investigations into the facility where the exceedance was discovered to determine if some other source(s) is causing the exceedance (e.g. leaking underground storage tanks).

EPA has reviewed the results of one year's quarterly sampling data and has overseen the installation of additional wells in this area in 2006. Bottled water has been provided to the facility affected by this gorundwater contamination. ODW continues measures to insure that no one at the facility or nearby is exposed to drinking water from this well following the discovery of elevated levels of 1,2 dichloroethane. Arrangements to provide for extension of and connection to the municipal water supply for the businesses and residences whose wells were contaminated was agreed to by the PRPs last year. This work will be conducted voluntarily by the site PRPs under EPA, DNREC and DE ODW oversight and should be completed in early 2009. The Site's third Five-Year review is planned for later this year.

Contacts

Site Contacts

Administrative Record Locations