Tower Chemical
Tower ChemicalEPA ID: FLD004065546
Location: Clermont, Lake County, FL
Congressional District: 6
NPL Status: Proposed: 12/30/82; Final: 09/08/83
Project Manager
Site Repository:
Cooper Memorial Library
620 W. Montrose St.
Clermont FL 34711
Documents:
![About Adobe Portable Document Format](https://webarchive.library.unt.edu/eot2008/20090513003047im_/http://www.epa.gov/superfund/pics/acrobat.gif)
- Site Profile
- Administrative Record Index (PDF): October 2006, OU3, Amend (2 pp., 66K), OU1 (1 pp., 49K)
- Reuse Ready Fact Sheet (PDF, 1 pp., 131K)
- Additional Site Documents including Five Year Reviews, Records of Decisions (ROD) and Explanation of Significant Differences (ESD).
- For documents not available on the website, please contact the Region 4 Freedom of Information Office (http://www.epa.gov/region4/foiapgs/submit.htm).
Site Background:
The Tower Chemical Company (TCC) Site is a 15-acre abandoned pesticide manufacturing facility located approximately 5 miles east of downtown Clermont, in Lake County, Florida. From 1957 to 1981, TCC manufactured and stored various pesticides used primarily in the citrus industry. TCC discharged acidic process wastewater into a 0.5-acre, unlined seepage/evaporation pond, which was located over a relict sinkhole. This created a leaching conduit into the deeper Floridan aquifer. TCC also burned and buried its waste on a 1.5-acre portion of the Site. In 1980, the wastewater pond overflowed into an onsite drainage ditch which flows downstream into the Gourd Neck of Lake Apopka, where vegetation and aquatic animals were affected. TCC stopped all discharges into the pond after a State Circuit Court order in July 1980. TCC ceased manufacturing operations in December 1980.
The bulk of the contaminants of concern are pesticide-related compounds (DDT, Chlorobenzilate, and their partial-breakdown compounds) both in the soil and groundwater originating from production activities at the Site. The contamination has primarily impacted the shallow groundwater aquifer on-site. The relict sinkhole has allowed some impact to the deeper Floridan aquifer. The site is located in an area of mixed agricultural, residential and commercial/industrial uses. Areas surrounding the site are experiencing significant development pressure. This site is being addressed through Federal and State actions.
Cleanup Progress:
In the 1980s, as a result of non-participation by the responsible party, EPA treated and discharged one million gallons of wastewater from the pond. EPA also excavated and disposed of 3,820 cubic yards of contaminated soil and sediment and 72 drums of other hazardous wastes from the pond and burn/burial pit areas. EPA built a system to divert surface water runoff away from the remaining contamination onsite and also fenced the area. These actions were conducted to prevent the continued spread of residual onsite contaminants in the wastewater pond and burn/burial pit areas. A ROD was signed in 1986 to address the remaining contamination at the site. In early 1990, prior to implementing the remedial design of the 1986 ROD, EPA re-sampled the soil and found the contaminant concentrations to be significantly lower. As a result, the planned remedial action, soil excavation and onsite incineration, was halted while additional investigation occurred.
Additional groundwater data identified that pesticide partial breakdown products (metabolites) and other organic contaminants persisted in the onsite groundwater. In addition, March 1997 soil data showed pesticides and their metabolites were present to a depth of 28 feet below land surface. Fieldwork designed to update site conditions was concluded by mid-1998. This data was summarized in the January 1999 Tower Chemical Reassessment Report. Monitoring of nearby residential potable water wells was also undertaken at this time.
EPA addressed possible offsite migration of contaminated groundwater in the Floridan Aquifer through an Interim-Action ROD in August 2000. The installation of eight carbon adsorption filters on six nearby residential wells was accomplished in January 2003. This interim action was done for the purpose of protecting residents living in the immediate vicinity of the site who consume the groundwater. Periodic groundwater monitoring continues. Replacement of the activated carbon in the filter systems occurred in mid-2003, 2005, and early 2007.
In 2001, EPA attempted to better identify the partial breakdown compounds present in the site’s groundwater and determine their toxicities. Groundwater samples were sent to EPA’s Office of Research and Development (ORD) laboratory for analysis using high resolution mass spectrometry. This resulted in the identification of 29 compounds which were forwarded to ORD’s toxicologists for modeling, since published toxicity information did not exist for the majority of these compounds. The goal of the toxicological modeling was to estimate the risks posed by the compounds identified. A major drawback to this modeling was that it was only capable of estimating risks due to non-cancer effects. In the fall of 2003, EPA and FDEP agreed that rather than continue trying to identify the majority of the site’s contaminants and determine their toxicities, a site-related compound (4,4'-dichlorobenzophenone) would be used as an indicator compound and clean-up alternatives would be evaluated in a supplemental feasibility study, employing margins of safety in establishing cleanup goals to compensate for the analytical and toxicological uncertainties encountered at this site.
In the summer of 2004, EPA performed detailed subsurface soil delineation work for the indicator compound 4,4'-dichlorobenzophenone, both a waste product when the site was active and a degradation product of the chemicals used and produced at the site. In addition, site groundwater was evaluated in acute and chronic toxicity tests. All additional data was incorporated into the Supplemental Feasibility Study and used to develop a Proposed Plan. A Proposed Plan public meeting was held on May 23, 2006 to summarize the contamination findings, identify the alternatives considered, and propose a preferred remedy. A formal public comment period ran from May 15 through June 15, 2006.
A site-wide Record of Decision (ROD) was signed in September 2006. The ROD addresses soil, groundwater, and potential sediment contamination. Shallow soils and sediments exceeding the remedial goals will be excavated and disposed off-site. Remaining deep soils and groundwater will be treated in-place using enhanced biological degradation, possibly supplemented with chemical and/or physical treatment.
Remedial Design field work was initiated in mid-October 2007 and lasted 5 weeks. This effort focused on the detailed delineation of soil excavation and in-situ treatment areas for incorporation in the remedial design documents. Once data results are evaluated, data gaps will be identified and additional data needs assessed. Concurrently, a treatability study is being planned to identify the best combination of technologies to address the remaining contamination in-place. Excavation and off-site disposal of contaminated shallow soils exceeding cleanup goals is targeted for mid-to-late 2008. Groundwater cleanup is currently targeted to begin full implementation in 2009 after results of the treatability study are evaluated.
EPA continues to monitor and maintain the eight carbon filter systems while, concurrently, designing permanent connections to the municipal water supply line which now runs along County Road 455. Connections to the municipal water supply are planned for mid-to-late 2008. A Five-Year Review, triggered by the installation of the carbon filter systems is also underway. It is scheduled for completion in January 2008.
The TCC site has been purchased and unaffected portions are being reused for commercial and recreational vehicle storage. The current owner is working closely with EPA to avoid placing permanent structures in areas requiring future cleanup actions.