Mid-Atlantic Superfund

EPA Region 3 (Mid-Atlantic)

Delaware
New Castle County
Delaware City

EPA ID# DED041212473

1st Congressional District

Last Update: October 2009

Other Names

Metachem Products, LLC

Current Site Status

EPA has been operating an interim groundwater remedy since June 2007, including a subsurface barrier wall around the former plant area and a system to pump and treat the contaminated ground water inside the barrier wall.

In September, 2004, EPA issued Amendment No. 1 to the 1995 Record of Decision. This Amendment selected Off-site Incineration as the disposal method for the approximately 1.3 million gallons of bulk liquid chemicals to be removed from the site. Some of the chemicals to be disposed of were solidified in portable transport containers referred to as totes. Disposal of the chemicals in the totes began in January 2006 and was completed in August 2009. This disposal had originally been expected to require until 2012 to complete, but the pace of disposal was accelerated through the use of federal stimulus funds made available through the American Recovery and Reinvestment Act (ARRA).

EPA has a number of other activities going on, some on-site, some off-site. Included among these are the the Remedial Investigation of soils on the former plant, groundwater monitoring; a study of the groundwater in the Potomac Aquifer beneath the Site; and a study of In-situ Chemical Oxidation, a technology that could potentially be used for treatment of contaminated soils and sediments. See the Cleanup Progress section below for details.

Site Description

The Standard Chlorine of Delaware, Inc. Site (aka Metachem) is located in New Castle County, Delaware (1st Congressional district). Chlorinated benzene compounds were made on the Site from 1966 to 2002. The Site was listed on the National Priorities List (NPL) of most hazardous waste sites in 1987 due to a 1981 chlorobenzene spill which occurred while workers were filling a railroad tanker car on the property. An additional spill occurred in 1986; 569,000 gallons of various volatile organic compounds (VOCs) spilled after a 375,000-gallon tank of VOCs split open, collapsed, and damaged three nearby tanks of VOCs, causing the latter tanks to partially spill.

Chlorobenzenes from spilled material have been found in the groundwater, soil, sediments, and surface water. Wetlands near the site are also contaminated. The State maintains a fish consumption advisory on Red Lion Creek for PCBs and dioxin. About 152,000 people draw groundwater from public and private wells within a three-mile radius of the site. Approximately 30 people reside within a mile of the site.

Site Responsibility

Cleanup of this site is the responsibility of federal and state governments.

NPL Listing History

This site was proposed to the National Priorities List of the most serious uncontrolled or abandoned hazardous waste sites requiring long term remedial action on September 18, 1985. The site was formally added to the list on July 22, 1987, making it eligible for federal cleanup funds.

Threats and Contaminants

Chlorobenzenes from spilled material have been found in the ground water, soil, sediments, and surface water. People may be exposed to the chemicals by direct contact with contaminated soil or accidentally ingesting contaminated soil or water. Wetlands near the site are impacted by contamination that emanated from the spill areas. The levels of contamination in the soils, surface water, and sediment may impact the quality of the wildlife and the ecosystems along Red Lion Creek. Chlorobenzenes have been found in tissue of fish obtained from Red Lion Creek.

Contaminant descriptions and risk factors are available from the Agency for Toxic Substances and Disease Registry, an arm of the CDC.

Cleanup Progress

Threat Mitigated by Physical Cleanup Work

Delaware Department of Natural Resources and Environmental Control (DNREC) and Standard Chlorine took the following emergency actions in response to the January 1986 spill: (1) built a filter fence along the mouth of the wetland coves; (2) recovered some of the material which had flowed off-site; (3) constructed a dike to isolate contaminants; (4) excavated contaminated soils and sediments; and (5) constructed a pond to store dredged materials.

On January 12, 1988, DNREC entered into a Consent Order with Standard Chlorine of Delaware, Inc. to conduct Interim Remedial Actions and investigate the site and determine what effect the spills had on local groundwater quality, soil, and wetlands. EPA issued a Record of Decision (ROD) on March 9, 1995 which included an interim action for the groundwater and a final action for the soils and sediments. The interim action for the groundwater addressed containment of groundwater via a subsurface barrier; treatment of groundwater and resulting air emissions; source removal of Dense Non-Aqueous Phase Liquids (DNAPLs) and further investigation of groundwater and DNAPLs. The final remedy for soils and sediments was biological treatment. Design studies indicated that bioremediation was not feasible for the site, so EPA switched to the contingency remedy, which was low temperature thermal desorption. A design comparison study of low temperature thermal desorption completed in 2003 indicated it was not likely to be cost-effective, so EPA is looking for alternatives. EPA is studying the feasibility of using In-situ Chemical Oxidation instead. The laboratory phase of this feasibility study was completed in Spring 2005, with an on-site field test of the technology completed in 2007. A final decision from EPA regarding In-Situ Chemical Oxidation is on hold as other tests are performed to measure the levels and extent of Polychlorinated Biphenyls (PCBs) in the wetland sediments, which would not be treatable by In-Situ Chemical Oxidation.

In May of 1996, EPA issued Standard Chlorine a Unilateral Order for implementation of a portion of the work outlined in the March 1995 ROD. The Remedial Design Work Plan (RDWP) was developed by Standard Chlorine for implementation of the interim groundwater remedy. In 1998, Standard Chlorine sold the plant to Metachem Products, LLC. In May 2002, following the abrupt closure, bankruptcy, and abandonment of the plant by Metachem, EPA and DNREC began an emergency removal action to stabilize the site that continued through September 2006. This emergency removal action included such actions as maintaining security and securing chemicals left onsite in numerous tanks and vessels.

Due to its bankruptcy, Metachem is unable to perform further cleanup, so EPA will complete the remainder of the original cleanup, including the completion of a groundwater barrier and pump-and-treat system and treatment of contaminated soils. By May 2002, when Metachem Products LLC declared bankruptcy and abandoned the Site, the Remedial Design of the interim groundwater remedy was 60% complete. EPA took over and completed the design in late 2005. Construction of the groundwater barrier and pump-and-treat system was completed in June 2007 and those systems are now operating.

EPA is analyzing data collected for the Remedial Investigation of the former Metachem plant and surrounding areas that were not previously investigated. The risk assessment process is now underway. EPA expects to issue a publish and request public comment on a proposed cleanup plan later in 2009.

EPA and DNREC are continuing to monitor the movement of contaminated groundwater beneath the site. Several rounds of sampling data confirm the presence of low levels of site-related contamination in the Potomac Aquifer. EPA brought in the United States Geological Survey (USGS) to conduct a study of the Potomac Aquifer beneath the Site to assist EPA in its mission to protect human health and the environment.

In September, 2004, EPA issued Amendment No. 1 to the 1995 Record of Decision. This Amendment selected Off-site Incineration as the disposal method for the approximately 1.3 million gallons of bulk liquid chemicals to be removed from the site. Some of the chemicals to be disposed of have been solidified in portable transport containers referred to as totes. Disposal of the chemicals in the totes began in January 2006 and was completed in August 2009. This disposal had originally been expected to require until 2012 to complete, but the pace of disposal was accelerated through the use of federal stimulus funds made available through the American Recovery and Reinvestment Act (ARRA).

Contacts

Site Contacts

Administrative Record Locations