Stauffer Chemical Company (Tarpon Springs)

Stauffer Chemical Company (Tarpon Springs)
EPA ID: FLD010596013
Location: Tarpon Springs, Pinellas County, FL
Congressional District: 09
NPL Status: Proposed: 02/07/92; Final 05/31/94
Project Manager
Site Repository:
Tarpon Springs Public Library
138 E. Lemon ST.
Tarpon Springs, FL 34689
Documents:

• Site Profile
• Administrative Record Index (PDF): Removal (3 pp., 112K), OU1 (15 pp., 631K)
• Stauffer Information Pages
• Record of Decision OU1
• 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 Tarpon Springs plant produced elemental phosphorous using phosphate ore mined from deposits in Florida. The plant was originally constructed and operated by Victor Chemical Company, which began production in 1947. The Stauffer Chemical Company obtained the plant from Victor Chemical in 1960 and continued to manufacture elemental phosphorous until the plant closed in 1981. The 160-Acre site (130 acres dry) is situated along the Anclote River approximately two miles upstream of the Gulf of Mexico. The site is approximately 1 mile north of the City of Tarpon Springs. Surrounding land use includes light industrial, commercial, recreational, and residential.

The Remedial Investigation was started in 1993 and completed in 1996; the site was listed on the National Priorities List. The contaminants of concern include heavy metals, radionuclides, Polynuclear Aromatic Hydrocarbons, and elemental phosphorous. Media contaminated include on-site soils, on-site waste ponds, and ground water.

Cleanup Progress: Threat Mitigated by Physical Clean-up Work; Design Complete for  Final Soil Cleanup

The design has been completed for the selected soil remedy.  EPA had sent out a fact sheet to the public in October 2008 describing the pre-final design report.  The Remedial Action (RA) workplans are now being developed and Stauffer is interviewing potential construction contractors. he RA workplans will provide plans for day to day operations, updated construction schedule, sequence of work, etc.  Once the RA workplans are completed, we will have a more specific start date for the construction.   The current estimate is that the construction could begin in the summer of 2009 and be completed during 2011.

As noted in the previous update, there are a few items of note:

1. There will be two capped areas at the Site, one in the north parcel and one in the south parcel.  The use of two capped areas eliminates the transport of material between the two parcels and reduces the overall height of the capped areas.
2. The design includes restoration of the eastern shore of Meyers Cove by excavation of the adjacent Pond 42.  Materials excavated from Pond 42 will be placed within the footprint of the planned cap on the southern parcel.
3. Ponds 42, 39, and the northern pond are the only waste ponds to be excavated. These ponds contain less phosphorus (than the southern ponds) and are more suitable for excavation.  However, if significant amounts of phosphorus are encountered during excavation, then the material may be capped in place without further excavation.
4. Future commercial/industrial use of the Site is possible after construction is complete.  It appears that the likely future uses are related to boating: marina, boat launch, boat storage, boat sales and service, parking, etc.
5. Future uses of the Site must be compatible with, and protective of, the completed remedy.

Summary of prior site activities
Under a removal action, the Stauffer Management Company removed approximately 33,000 gallons of elemental phosphorous contained in on-site above-ground tanks in 1997-1998.

The EPA signed a Record of Decision in July 1998 calling for in-situ solidification/stabilization of pond material below the water table; consolidation and on-site capping of contaminated soils and other materials; and institutional controls to prevent future residential land use at the site.

The EPA and Stauffer Management Company initially signed a Consent Decree in 1999 to implement the selected remedy. In response to public comments, the initial Consent Decree was withdrawn and additional geophysical studies were performed at the Site.  The additional studies were conducted during 2000-2004 to evaluate the suitability of the remedy.  The geophysical studies concluded that the remedy can be safely implemented at the Site.  Stauffer Management Company and EPA signed another Consent Decree for the design and cleanup at the Site in April 2005.  The Consent Decree was lodged with the district court in June 2005.

In June 2007, EPA determined that it was necessary to change the in-situ solidification component of the remedy (see Summary of Explanation of Significant Differencesdated June 2007).  A groundwater “cut off” wall for the use of in-situ solidification (ISS) to reduce the potential for contaminant migration from the former waste ponds.  EPA plans to make this change because of implementation issues identified during the pilot testing of the ISS technology.   During this testing, a reaction occurred between elemental phosphorus and the cement slurry which contributed to a fire in the test area.  In addition, there is debris in portions of the old ponds which makes solidification impracticable.  Some of the debris likely contains residual elemental phosphorus.

The use of a cut off wall will reduce the movement of groundwater contamination.  The wall would be installed below ground around the perimeter of the former waste ponds.  Modifying this component of the remedy will avoid the problems associated with implementing ISS at full scale.  (Some community members requested that the cutoff wall design be reviewed by a local university professor.  The professor has reviewed the preliminary design and agrees with the design of the cutoff wall.)

Other components of the remedy, including capping and restrictions regarding future on-site groundwater use and land use, remain unchanged.  The capping called for in the ROD will cover contaminated soil including the area inside the subsurface cut off wall and will form a protective barrier designed to prevent contact with contaminated materials.