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Case Summary: EPA Transfers Cleanup Oversight to Florida to Support State Regulatory Consistency Over Former Phosphate Mining Sites

In October 2017, oversight of the cleanup work at the Coronet Industries, Inc. Superfund Alternative Site, was transferred from the U.S. Environmental Protection Agency (EPA) to the Florida Department of Environmental Protection (FDEP). The EPA and the FDEP agreed to transfer oversight of the cleanup work to support state regulatory consistency in the cleanup of former phosphate mining sites located in Florida. The cleanup will be conducted by Hexion Inc., CEMEX Construction Materials Florida LLC, and Coronet Industries, Inc., under a state cleanup agreement.

Three agreements were negotiated to complete the transfer of the oversight work from the EPA under CERCLA to the state of Florida, including an administrative settlement for the recovery of past costs in which the parties agreed to pay the EPA $1.9 million.

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Information about the Companies

  • Hexion, Inc.: Hexion, Inc.’s and its predecessors, the Coronet Phosphate Company (CPC) (no relation to Coronet Industries, Inc.), the Smith Douglas Company, the Bordon Company, Bordon, Inc., and Bordon Chemical, Inc., entities owned and operated the 2,500-acre tract between 1906 and 1980. In 1906, CPC began phosphate mining on a 2,500-acre tract of land near Plant City, Florida. Mining operations ceased in 1940. In 1946, CPC began producing “Coronet Defluorinated Phosphate” (CDP), at a manufacturing facility (the Main Plant) in the southern portion of the 2,500-acre tract. In 1952, Smith-Douglass Company, Inc. (Smith-Douglas) purchased the entire 2,500-acre tract, including the Main Plant area, and in 1958 Smith-Douglass began producing at the Main Plant (in addition to CDP) potassium fluoroborate (KBF4), which is used in the aluminum alloy and electronics industries. In 1964, the Borden Company purchased the entire 2,500-tract and manufactured CDP and KBF4 at the Main Plant until 1980.
  • CEMEX Materials of Florida, LLC (Cemex): Cemex and its predessesors, AMAX Phosphate, Inc., AMAX Chemical Corporation, and Consolidated Minerals, Inc., owned and operated the Site between 1980 and 1993. In 1980, Amax Phosphate, Inc. purchased the entire 2,500-acre tract and produced CDP and KBF4 at the Main Plant. In 1986, Amax changed its name to Consolidated Minerals, Inc. (CMI). Both Amax and CMI produced CDP and KBF4 at the Main Plant. CMI ceased manufacturing at the Main Plant when, in 1993, it sold a 980-acre portion of the 2,500-acre tract to Coronet.
  • Coronet Industries, Inc. (Coronet): In 1993, Coronet purchased a 980-acre portion of a 2,500-acre tract from Consolidated Minerals, Inc., which included: (1) the Main Plant area; an area surrounding the plant, numerous “holding ponds” and lagoons that treated and held wastewater from the manufacturing plant; and (3) other parcels on which waste piles were located. Coronet produced CDP, a nutritional supplement for animal feed and KBF4, which is used in the aluminum alloy and electronics industries until approximately March 2004, when production operations ceased.

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Information about the Coronet Industries Inc. Superfund Alternative Site

The Coronet Industries Inc. Superfund Alternative Site is located east of Plant City, Florida, and includes a 980-acre parcel, a 1,365-acre parcel and a handful of smaller parcels occupied by operating businesses. The site also includes a former phosphate ore mine and chemical plant. The Coronet Phosphate Company (separate from Coronet Industries, Inc.) began mining operations at the site in 1906 and conducted phosphate mining operations on portions of the site until about 1940. The company deposited mining wastes that contained smaller particles of phosphate rock, sand and clay on several areas at the site, including the land surface, pond bottoms and construction sub-base.

EPA did not list the site on the NPL, but considers it an NPL-caliber site and is addressing the site through the Superfund Alternative Approach. This approach uses the same investigation and cleanup process and standards used for sites listed on the NPL. Portions of the site are currently being used for such business as cattle grazing. Parties are evaluating redevelopment opportunities for additional future use.

More information on the site is available from the Coronet Industries Plant City, FL site profile page.

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Overview of the Agreements

Pursuant to a 2007 agreement with EPA, Coronet Industries conducted a Remedial Investigation (RI) to characterize the nature and extent of contamination and potential risks posed by the site. The RI Report was approved by EPA in December 2013, and thereafter the agreement was modified to limit the work requirement to the RI in furtherance of the transfer of the site to the state.  

To implement the transfer, three agreements were negotiated:

  1. Modification to an existing work agreement between EPA and Coronet, which limits Coronet’s obligations to work already completed;
  2. Administrative settlement pursuant to which three PRPs, including Coronet will pay $1.9 million in past costs to the EPA; and
  3. State cleanup agreement between the three PRPs and the FDEP that provides for the completion of the remediation at the Site.

To meet EPA’s conditions for transfer, the final state cleanup agreement includes financial assurance requirements and a technical assistance plan (TAP) provision providing a qualified community group  up to $50,000 for technical assistance.

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Contact Information

For more information, contact

Elisa Roberts
Site Attorney
Office of Regional Counsel
U.S. Environmental Protection Agency
Region 4
61 Forsyth Street, SW
Atlanta, GA  30303

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