KOPPERS CO., INC. (CHARLESTON PLANT)
CHARLESTON, SC
Cleanup Activities
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On this page:
- Background
- What Has Been Done to Clean Up the Site?
- What Is the Current Site Status?
- Activity and Use Limitations
- Enforcement Information
On related pages:
Background
The Koppers Co., Inc. (Charleston Plant) site is located in Charleston, South Carolina. It includes the area where the Koppers Company operated a wood treatment facility from 1940 to 1978. EPA placed the site on the Superfund program’s National Priorities List (NPL) in 1994 because of contaminated groundwater, sediment, soil and surface water resulting from facility operations. EPA, the South Carolina Department of Health and Environmental Control (SCDHEC) and Beazer East, Inc., the site’s potentially responsible party (PRP), have investigated site conditions and taken steps to clean up the site in order to protect people and the environment from contamination.
EPA selected a cleanup plan for the site in an Interim Action Record of Decision (ROD) in 1995 and in a ROD in 1998. EPA modified the remedy in an Explanation of Significant Differences (ESD) in 2001 and a second ESD in 2003. EPA most recently changed the remedy in a February 2018 ROD Amendment.
Site contamination does not currently threaten people living and working near the site. A water line connects residents and businesses to the public water supply. By treating and monitoring groundwater, placing institutional controls on the site property and undertaking Five-Year Reviews, EPA, SCDHEC and the site’s PRP continue to protect people and the environment from site contamination.
What Has Been Done to Clean Up the Site?
The 102-acre site is located on the west side of a peninsula formed by the confluence of the Ashley and Cooper Rivers in Charleston, South Carolina. Industrial, commercial and residential properties border the site to the north, south and east. Rosemont, a neighborhood with low-income and minority residents, is located just north of the site. The Macalloy Corporation Superfund site is located a half-mile north of the site. From 1940 to 1978, the Koppers Company operated a wood treatment facility on a 45-acre portion of the site. Operations included treating raw lumber and utility poles and using aboveground storage tanks for wood preservatives. Following wood treating operations, the Koppers Company leased the area to several other companies, including Fed Serv, Pepper Industries and Braswell Shipyards, for facility operations.
The Koppers Company changed its name to Beazer East, Inc in 1990. The Koppers Company never owned the remaining 57 acres of the site located south of the wood treatment facility. Ashepoo Phosphate/Fertilizer Works owned the area and operated a phosphate and fertilizer production facility in this area from 1900 until 1978. After obtaining a permit from the U.S. Army Corps of Engineers, Southern Dredging excavated a barge canal in 1984 that extended approximately 1,000 feet inward from the Ashley River. The EPA incorporated the 57 acres into the site’s boundaries to determine the environmental impact of previous dredging operations on the Ashley River and the neighboring tidal marsh. In 2003, Ashley LLC purchased the site property parcels previously owned by Beazer East, Inc. Ashley LLC planned to redevelop the area as part of Magnolia, a 218-acre mixed-use project with residential, commercial retail and office/hotel space and parks. That effort stalled when the economic recession hit in 2009. The southern portion of the site is currently vacant.
- Beazer East, Inc., the site’s PRP, leads site investigation, cleanup and operation and maintenance activities, with oversight provided by EPA and SCDHEC.
- In 1983, Pepper Industries began cleanup activities on the part of the site owned by the Koppers Company. Pepper Industries then declared bankruptcy and ceased all cleanup activities. Braswell Shipyards conducted cleanup activities at the property in 1987, including removing storage tanks and containers and arranging for proper disposal of the wastes. The Koppers Company funded half the expense of this cleanup operation.
- In 1985, Fed Serv, the Koppers Company and several other parties began short-term cleanup activities at the former wood treatment facility’s tank farm area, disposing of material in the tanks, demolishing the tanks, and digging up and disposing of contaminated soils. From 1997 to 2003, Beazer East, Inc., the site’s PRP, conducted cleanup activities, digging up and disposing of 22,000 tons of contaminated soils, placing a 40-acre cap over contaminated soils, rebuilding 3,600 feet of drainage ditches, restoring tidal marshes and placing a 3-acre cap over Ashley River sediments. From 2003 to 2010, the PRP recovered creosote from groundwater beneath the site.
- EPA completed the site’s third Five-Year Review (FYR) in 2013. It found additional information is needed to address the potential for vapors entering indoor air from the subsurface. The FYR estimated that it would take one year to complete these actions.
What Is the Current Site Status?
In 1995, EPA issued an interim cleanup plan to address the spread of contaminants and eliminate chances that people could encounter site contamination. EPA selected the site’s final remedy in 1998. It included digging up and disposing of contaminated soil off site, and placing a cap over contaminated soil on site. It also included rebuilding drainage ditches; placing an underwater cap in the barge canal; covering contaminated sediment with clean sediment in the Ashley River; cleaning up disturbed tidal marshes; and cleaning up groundwater contamination.
In 2001 and 2003, EPA updated cleanup plans for the Ashley River, placing an underwater cap over river sediments, and cleanup activities for the Barge Canal cleanup, changing groundwater treatment to monitored natural attenuation processes. The remedy updates also included the stabilization/solidification of creosote.
Also, in 2001, EPA changed the cleanup of the Ashley River from enhanced sedimentation to placement of an engineered, subaqueous cap. In 2003, EPA changed the barge canal cleanup plan from placement of an engineered, subaqueous cap to natural dosition and monitored natural recovery. The cleanup plan also changed the groundwater and non-aqueous phase liquid (NAPL) component for the northwest corner of the site from active NAPL recovery with extraction wells to immobilization using stabilization and solidification techniques.
The creosote and ground water recovery systems continue to operate at the site. Inspections and monitoring of the cap are ongoing. The remedial design for the ROD Amendment is about 80% complete. EPA is currently conducting the fourth Five-Year Review which is due to be completed in July 2018.
Activity and Use Limitations
At this site, activity and use limitations that EPA calls institutional controls are in place. Institutional controls play an important role in site remedies because they reduce exposure to contamination by limiting land or resource use. They also guide human behavior. For instance, zoning restrictions prevent land uses – such as residential uses – that are not consistent with the level of cleanup.
For more background, see Institutional Controls.
The July 2003 property deed prohibits residential development and ground water use at parcels purchased by Ashley I LLC.
Enforcement Information
The EPA negotiated legal agreements with the site PRP to investigate and clean up the site. The PRP continues to fund site cleanup, monitoring and oversight activities.