Mid-Atlantic Superfund

EPA Region 3 (Mid-Atlantic)

Delaware
New Castle County
Along the Christina River in Newport

EPA ID# DED980555122

1st Congressional District

Last Update: January 2009

Other Names

DuPont-Newport
Newport Pigments

Current Site Status

The U.S. Environmental Protection Agency (EPA) completed the cleanup of the DuPont site in September 2002. Work was carried out by DuPont with EPA oversight. To celebrate the completion, DuPont hosted a media event at the South Landfill that included presentations by EPA, DuPont and Delaware's Department of Natural Resources and Environmental Control (DNREC). The presentations focused on how each party brought its expertise to the project in a cooperative manner that resulted in a cleanup that was more extensive than EPA originally envisioned and that was at a lower cost and ahead of schedule. Operations, maintenance and monitoring activities are on-going at this time. These mainly involve the ground water recovery and treatment operations and monitoring the restoration of the wetland and river areas that were cleaned up.

EPA completed the first Five-Year review of the overall remedy of the DuPont Site in March of 2005. The review stated that the Site is protective of human health but that there are a number of minor issues that EPA will work with the PRPs to resolve. Of these tasks, the most important is the christiana river off-site depositional area, EPA and DuPont are working jointly to better understand this portion of the site and determine if any further remediation is necessary.

Site Description

The E.I. DuPont, Newport site encompasses a pigment-manufacturing facility and two industrial landfills. The Christina River flows between the 7-acre North Landfill and the 15-acre South Landfill. From 1902 to 1929, Henrik Krebs built the plant and used it to manufacture a white zinc- and barium-based pigment called Lithopone.

In 1929, DuPont bought the plant. Over the next several decades, DuPont phased out Lithopone production and started making other organic and inorganic pigments. Other assorted products were made at the site, including chromium dioxide. As part of the plant’s operations, waste was disposed of in the landfills. At times these landfills did not contain the waste, and it flowed into the bordering wetlands and the Christina River. Wastes put in these landfills contained metals such as lead, cadmium, zinc, barium, mercury, and copper.

Before the Superfund laws were created, the State purchased a section of the South Landfill as part of a highway construction project. In 1984, Ciba-Geigy (now Ciba Specialty Chemicals) bought the pigment plant; DuPont retained the chromium dioxide manufacturing facility, which has since been shut down.

Part of the site is located adjacent to a residential area. There are public water supply wells within a 3-mile radius of the site but they are not impacted by the site. The river that flows between the landfills is used for recreational purposes.

Site Responsibility

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

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 cleanup action on January 22, 1987. The site was formally added to the list on February 21, 1990, making it eligible for federal cleanup funds.

Threats and Contaminants

Heavy metals and chlorinated solvents from past operations and disposal practices have been detected in the ground water. Very high levels of heavy metals were found at the landfills, underneath the Ciba plant, in river sediments and in wetland sediments. These metals include: lead, cadmium, zinc, barium, mercury and copper.

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

Cleanup Progress

As a result of a legal consent agreement with EPA, DuPont installed a steel wall using sheet piles along 700 feet of the Christina River in 1994. This barrier prevents oil from seeping out of the river bank.

DuPont carried out the rest of the cleanup work outlined in EPA’s August 1993 formal cleanup decision under an EPA order (Unilateral Administrative Order) issued in April 1994. In 1995, several cubic yards of lead-contaminated soil were removed from an adjacent baseball field which the Town of Newport is now leasing from DuPont. That same year, DuPont installed a water line to nearby residents who were drinking from private wells.

In March 1997, the south river bank was covered with rocks, preventing further erosion into the South Landfill. In August 1997, work started to remove highly-contaminated sediments from the North Wetlands. Approximately 10,000 yards of wetland sediments were dug up and disposed of on-site in the North Landfill. The North Wetlands were replanted and restored. Cooperation between EPA, Delaware’s Department of Natural Resources and Environmental Control (DNREC), and DuPont resulted in DuPont excavating more contaminated sediments than originally planned and increasing the biodiversity of the area. Excavation of contaminated sediments from the South Wetlands and related restoration and replanting was finished in early 1999. Again, cooperative efforts between DuPont, DNREC, and EPA resulted in DuPont increasing both the biodiversity and amount of wetland acreage, plus removing more contamination than originally planned.

In November 1999, DuPont finished dredging the Christina River. Approximately 11,000 cubic yards of contaminated sediments were removed from three areas. This work will protect the aquatic life in the river. Dredged sediments were put in the South Landfill, which DuPont capped in 2002.

In May 2001, DuPont completed capping the North Landfill. To capture polluted groundwater from underneath the landfill and the Ciba plant, DuPont also installed a groundwater capture system. Groundwater is being treated on-site before it is pumped to the Wilmington Treatment Plant.

The last phase of the cleanup involved the South Landfill. In May 2001, EPA issued an Explanation of Significant Difference that modified the cleanup plan for the landfill. The new plan, which included an in-ground reactive wall to treat ground water and a landfill cap, significantly reduced impacts to South James Street during construction (South James Street runs over the top of the landfill). Construction started in December of 2001 and ended in September 2002.

Contacts

Site Contacts

Administrative Record Locations