Calhoun Park Area
Site Summary ProfileEPA ID: SCD987581337
Location: Charleston, Charleston County, SC
Lat/Long: 32.79154, -0 79.927219
Congressional District: 06
NPL Status: Superfund Alternative Approach
Affected Media: Ground water, Soil, Sediment, Surface Water
Cleanup Status: Physical cleanup activities are underway
Human Exposure Under Control: NA
Groundwater Migration Under Control: NA
Sitewide Ready for Anticipated Use: NA
Site Reuse/Redevelopment: In continued use – industrial and commercial land uses are located on site
Site Manager: Ken Mallary (firstname.lastname@example.org)
Current Site Status
The Calhoun Park Area site includes an area near Charleston Harbor in Charleston, South Carolina where several industries have operated since 1855. EPA did not list the site on the National Priorities List (NPL) but considers it an NPL-caliber site and is addressing it through the Superfund Alternative Approach. EPA, the South Carolina Department of Health and Environmental Control (SCDHEC), and South Carolina Electric and Gas Company (SCE&G), the site’s PRP, have investigated site conditions and taken steps to clean up the site in order to protect people and the environment from contamination. Site contamination does not currently threaten people living and working near the site. By treating and monitoring ground water, EPA, SCDHEC and the site’s PRP continue to protect people and the environment from site contamination.
The site is located one block from the Charleston Harbor in Charleston, South Carolina. The site generally includes the area within the borders of Charlotte, Concord, Calhoun, and Washington Streets, which includes an electrical substation property owned by SCE&G and a large parking garage. Site surroundings include a park, aquarium, commercial businesses, and the Cooper River to the east, a large parking lot to the north, a residential development and open fields to the south, and various commercial and residential developments to the west. The site has also affected portions of nearby properties east of the site and the Cooper River.
Since 1855, industries operating at the site have included a manufactured gas plant, a wood treating plant, a shipyard and a dry dock. The manufactured gas plant operated from 1855 to 1957. Operations included producing town gas by heating coal in the absence of oxygen and delivering the gas to homes and businesses as fuel for gas lamps and cooking stoves. Operations resulted in liquid coal tar, a waste byproduct of the production process.
Site investigations found contamination in ground water, soil, sediment and surface water that could potentially harm people in the area. Contamination resulted from manufactured gas operations at the site. Contaminants of concern include polycyclic aromatic hydrocarbons (PAHs), volatile organic compounds (VOCs), arsenic and beryllium. Investigators also observed coal tar in sediments, surface waters, and seeps along the adjacent Cooper River as well as free coal tar product in the ground water at four locations underlying the site.
Contamination remains in ground water; however, residents and businesses are not using the impacted ground water. Ground water monitoring and treatment of ground water continues.
The PRP has addressed soil contamination. The soil cleanup permits residential uses.
The PRP has addressed most of the site-related contaminated sediment in the Cooper River through the placement of sand caps.
The electrical substation area is fenced and secured.
EPA has determined that vapor intriusion is not a threat to people living or working on or near the site.
Investigation and Cleanup Responsibility / Oversight
The site’s PRP, SCE&G, leads site investigation and cleanup activities, with oversight provided by EPA and SCDHEC.
Site Cleanup Plan
Site investigations and cleanup activities have focused on two areas, which EPA refers to as operable units, or OUs. These areas include OU-1: soil, non-aqueous phase liquid (NAPL) and shallow ground water; and OU-2: surface water, intermediate ground water and sediments in the Cooper River.
In 1998, EPA issued a cleanup plan (a Record of Decision, or ROD) for OU-1. The plan included the following activities:
- Digging up and transporting contaminated soil to an off-site landfill.
- Backfilling the dug-up areas with clean soil.
- Removing the NAPL source areas located in the ground water aquifer.
- Using recovery wells, a filtration system, and green plants and their associated microorganisms to break down contamination in ground water.
- Sampling surface water and sediment to determine the extent of contamination.
In 2002, EPA issued the cleanup plan (ROD) for OU-2. The plan included the following activities:
- Using pumping equipment to remove NAPL from ground water.
- Treating ground water using chemicals to break down contaminants.
- Evaluating measures to contain NAPL if removal activities do not limit the potential migration of the contamination.
- Monitoring ground water.
- Placing institutional controls on the site property to restrict ground water use.
In 2006, EPA issued an Explanation of Significant Differences (ESD) for OU-1 to address three additional areas of contamination and to update the cleanup plan to include the use of chemicals to limit the spread of source materials in inaccessible areas, including underground utilities and structures related to the SCE&G electrical substation.
In 1999, the site’s PRP began cleanup activities for OU-1. Cleanup activities included digging up 63,400 tons of contaminated soil and debris and disposing of the materials off site, installing approximately 50 NAPL recovery wells, collecting and treating three million gallons of ground water, and using green plants and their associated microorganisms to break down contamination in shallow ground water. The NAPL recovery system recovers approximately 100 to 400 gallons of contamination per month.
In 2004, the PRP began cleanup activities for OU-2. In 2005, the PRP began injecting chemicals into the aquifer to treat ground water. In 2006, the PRP capped sediment in Area 2 and Area 3 of the Cooper River. The PRP completed cleanup activities for OU-2 except for installation of the cap over Area 1 in the Cooper River.
The PRP completed cleanup activities for OU-1 in 2006.
The site’s first Five-Year Review, completed in 2009, found that the cleanup continues to protect people and the environment from remaining contamination.
EPA negotiated legal agreements with the site’s PRP to investigate and clean up the site. The PRP continues to fund site cleanup, monitoring and oversight activities.
EPA has worked with the community and its state partner to develop a long-term cleanup plan for the site, reflecting the Agency’s commitment to safe, healthy communities and environmental protection. Community engagement and public outreach are core components of EPA program activities.
EPA has conducted a range of community involvement activities to solicit community input and to make sure the public remains informed about site activities throughout the cleanup process. Outreach efforts have included public notices and interviews.
Ground water monitoring and use of the NAPL recovery system are ongoing.
The site’s PRP plans to complete the cap over Area 1 in the Cooper River. The capping work is on hold due to the construction of a new pier at the end of Charlotte Street.
EPA completed the last Five-Year Review in 2009 and plans to complete the next Five-Year Review in 2014.
EPA keeps additional site documents and information in a site information repository at the location below. EPA also posts site documents, when available, on EPA’s CERCLIS Site Profile page. For documents not available on the website, please contact the Region 4 Freedom of Information Office.
Charleston County Main Library
68 Calhoun Street
Charleston, SC 29401