Southern Solvents, Inc.
Site Summary ProfileEPA ID: FL0001209840
Location: Tampa, Hillsborough County, FL
Lat/Long: 28.040550, -082.510270
Congressional District: 08
NPL Status: Proposed: 05/11/00; Final: 07/27/00
Affected Media: Ground water, Soil
Cleanup Status: Construction Underway – physical cleanup activities have started
Human Exposure Under Control: Yes
Groundwater Migration Under Control: No
Sitewide Ready for Anticipated Use: No
Site Reuse/Redevelopment: In reuse – a commercial/light industrial land use is located on site
Site Manager: Galo Jackson (firstname.lastname@example.org)
Current Site Status
The Southern Solvents, Inc. site includes the area where a cleaning solvent distributor operated from the late 1970s to 1989. EPA placed the site on the National Priorities List (NPL) in 2000 because of contaminated soil and ground water resulting from periodic spills of cleaning solvents – substances used to dissolve other substances – at the site. EPA and the Florida Department of Environmental Protection (FDEP) 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. Both residents and businesses use the public water system for drinking water and the Northwest Florida Water Management District restricts well placement within the area of contamination. By treating surficial ground water and using periodic soil vapor extraction (SVE), EPA and FDEP continue to protect people and the environment from site contamination.
The 1-acre site is located in North Tampa, Hillsborough County, Florida. Mixed land uses surround the site, including a gas station to the east, a tire and rim shop and a condominium complex to the west, and a coffee distribution center to the north. West Linebaugh Avenue is located along the southern border of the site.
The site is the former location of a facility that distributed dry cleaning solvents, including tetrachloroethylene (also known as PCE or PERC) and trichloroethylene (TCE), to the local dry cleaning industry. The facility operated from the late 1970s to 1985 and resumed operations for a brief period from 1985 to 1989. PCE and TCE were reportedly stored in above-ground tanks and small tanker trucks on a concrete slab and on the northern portion of the site. Periodic spills from these storage tanks may be the source of soil and ground water contamination at the site.
A former tenant who signed a Prospective Purchaser Agreement with EPA when acquiring the property currently owns the site. The owner operates a painting business in a single-story building on the site.
In 2000, EPA listed the site on the NPL.
Site investigations identified contamination in surface and below-ground soils and ground water. Contamination resulted from periodic chemical spills on site. Contaminants of concern identified include PCE and TCE.
EPA detected the highest PCE concentrations in soils in the saturated zone beneath the former solvent storage area. The PCE concentrations were high enough that the contaminant was present as a dense non-aqueous phase liquid (DNAPL). On-site ground water contamination was most concentrated in the surficial aquifer and has leaked through a clay layer to affect the underlying Floridan Aquifer. This leak created an 18-acre plume of contaminated ground water. All area residences and businesses connect to the public water system. Hillsborough County also provides carbon filters for some wells in the area.
PCE and TCE are volatile organic compounds (VOCs), which are chemicals that can pose a risk through vapor intrusion. EPA treats the only area on site with VOCs in the surficial aquifer with an SVE system to prevent vapor intrusion. The ground water plume that extends off site is located within the Floridan Aquifer and the uncontaminated surficial aquifer above the Floridan Aquifer acts as a barrier to prevent off-site vapor intrusion issues. EPA will continue ground water cleanup until contaminant levels meet federal and state drinking water standards.
Some subsurface soil contamination remains on site. Aside from areas where EPA is treating soils, the Agency covered contaminated subsurface soil with clean soil to prevent exposure.
Land use controls at the site include fencing and secured gates to prevent access. The Southwest Florida Water Management District listed the site and nearby surrounding area as a ground water delineation area, which means all wells placed in the area require the district’s approval. The delineation area acts as an institutional control to prevent residents from coming into contact with contaminated ground water.
Investigation and Cleanup Responsibility / Oversight
EPA leads site investigation and cleanup activities in cooperation with FDEP.
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 and surficial aquifer cleanup; and OU-2: Floridan Aquifer cleanup. EPA issued a cleanup plan (a Record of Decision, or ROD) for OU-1 in 1999. The plan included the following activities:
- Digging up contaminated, unsaturated soils located in the former solvent storage area.
- Treating highly contaminated saturated soil and surficial ground water using in-situ chemical oxidation (ISCO).
- Evaluating continued ISCO use in areas with lower PCE concentrations.
- Restricting ground water use by designating the site as part of a Southwest Florida Water Management District ground water delineation area.
In 2002, with FDEP concurrence, EPA issued an Explanation of Significant Differences (ESD) to modify the OU-1 cleanup. Additional sampling during the initial cleanup design found a larger amount of soil contamination than had been previously identified, including soil contamination that EPA could not access beneath the facility building. In response, the ESD changed the soil cleanup from excavation to SVE. The ESD also clarified that EPA would conduct an ISCO pilot study prior to full-scale implementation to confirm the effectiveness of the technology in cleaning up ground water and possible DNAPL in the surficial aquifer.
EPA has taken several cleanup actions at the site. The remedial design for OU-1 included the treatment of the contaminated subsurface soil above the water table using an SVE system. The SVE system operated from June 2005 to June 2006. EPA addressed ground water contamination below the water table using ISCO. Under the ISCO pilot study work plan, EPA completed two phases of ISCO injections in April 2009. Ground water monitoring results from April 2010 indicated that 13 out of 18 wells monitored had declining PCE concentrations. However, PCE concentrations had increased in three of the monitored wells. EPA restarted the SVE system in early 2011 and operated it until July 2011, when soil vapor levels had declined. EPA will continue to operate the SVE system periodically as needed to address soil vapor until the Agency can confirm that soil vapor cleanup is complete.
EPA started a second remedial investigation/feasibility study to investigate ground water contamination in the deeper Floridan Aquifer in early 2000. The study identified substantial contamination in the aquifer. EPA installed monitoring wells. Sampling occurred most recently in 2009 and EPA will conduct additional sampling to update the ground water data in late 2011. EPA suspended work on OU-2 until the Agency can assess the status of the OU-1 cleanup.
EPA negotiated legal agreements with the site PRP to provide some funding for site investigations and cleanup. However, EPA is using federal funds for the majority of site cleanup 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, interviews and information meetings on cleanup progress and activities.
EPA anticipates a third ISCO application in fall 2011.
EPA will restart and operate the site’s SVE system periodically as needed in the future.
The remedial design for OU-2 will proceed once source contamination in OU-1 is under control.
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.
North Tampa Branch Library
8916 North Boulevard
Tampa, FL 33604