Date of incident: September 5-6, 2004.

Location: Riverview, Florida.

Trustees:

• National Oceanic and Atmospheric Administration (NOAA)
• U.S. Fish and Wildlife Services (FWS)
• Florida Department of Environmental Protection
• Environmental Protection Commission of Hillsborough County

Case status: Injury Assessment Phase.

Overview: On September 5, 2004, a berm atop a phosphogypsum stack failed during a severe weather event resulting in the release of acidic process water from the Mosaic Fertilizer, LLC phosphoric acid and fertilizer production facility in Riverview, Florida. The spill continued through September 6, 2004. An estimated 65 million gallons of acidic, nutrient-rich process water was released into Archie Creek Canal, Hillsborough Bay, and surrounding wetlands. The release resulted in areas of depressed pH and elevated levels of nitrogen and phosphorus that potentially caused natural resource injury to vegetated marshes, mangroves, benthic invertebrates, water column organisms, wildlife, and aquatic flora.

The Trustees are working cooperatively with Mosaic Fertilizer, LLC to assess these natural resource injuries and evaluate potential restoration options for the associated public compensation.