Additional Phosphate Mining Information

  • Mar 23, 2010
  • Greg Blanchard

This page provides additional topics of interest concerning phosphate mining as it relates to Manatee County’s citizens and environment.

Radiation

Uranium – A naturally occurring element found in numerous minerals, including phosphate rock. Although neither the mining nor processing of phosphate involves the addition of any radioactive substances, the digging up and turning over of soil to find and remove phosphate can increase radioactivity near the surface by bringing material containing uranium decay products once 30 feet underground to the surface. Therefore, Manatee County will not release reclaimed land without it meeting radiation standards set forth in the Phosphate Mining Code (Ordinance No. 04-39).

 
Radon - An odorless, colorless and tasteless, naturally occurring radioactive gas.
 

Clay Settling Areas (includes dam safety)

The area lying between earthen dams or within excavated areas, which is used primarily for impounding clays or other wastes, sometimes also referred to as a “slime pond” or an “initial” or “waste-clay” settling area. Clays are removed from the phosphate matrix during the beneficiation process. Clays present a disposal problem due to their size and rates, and they trap and retain large amounts of water and take long periods of time to dry. Accordingly, clays are placed in clay settling areas.

 

Dams surrounding clay settling areas should be engineered in keeping with best available technology, inspected frequently, carefully constructed and well maintained. The Florida Department of Environmental Protection, under its Administrative Rules, Chapter 62-672, Florida Administrative Code, requires operational and annual inspections of all earthen dams used in phosphate mining operations for the impoundment of liquid industrial wastes. The regulation requires that an independent, Florida-registered professional engineer perform the inspections.

 

Groundwater Utilization

Water is used to pump the slurry of matrix through the beneficiation process, sand to mine cuts, and clays to the clay settling area. Mine water balances and phosphate industry water use permitted withdraws are carefully reviewed for impacts on the aquifer. Water consumption and the construction and regulation of wells are regulated by the Water Management District. Monthly groundwater use and water level reports are submitted for agency review.

 

Conservation of water is encouraged as recycling of water in the phosphate mining industry is a common practice.

 

Listed Species and Their Habitats

Before mining begins, permits required by federal, state and local authorities must be in place which address wildlife under the regulatory authority of the Florida Fish and Wildlife Conservation Commission (FWC) and the U.S. Fish and Wildlife Service. Wildlife Habitat Management Plans are developed to avoid, minimize, and mitigate adverse impacts to state and federally listed wildlife species. Wildlife Habitat Management Plans usually include such species as the Florida scrub jay, gopher tortoise, southern bald eagle, eastern indigo snake, and Florida burrowing owl.

 

Transportation

Phosphate rock is loaded into covered trucks or railroad cars and transported to the customer or to a fertilizer chemical plant.

 

Phosphate Fertilizer Manufacturing Plant

A phosphate fertilizer manufacturing plant is also referred to as an Acid Plant. At the manufacturing plant the phosphate rock is reacted with sulfuric acid to create the phosphoric acid needed to make fertilizer and produces a by-product of phosphogypsum. The phosphoric acid is reacted with ammonia to create diammonium phosphate (commonly referred to as DAP). The DAP fertilizer is water-soluble and will be available for the plants to take up through their roots. There are no phosphate fertilizer manufacturing plants in operation in Manatee County.

 

Phosphogypsum Management (link to FDEP)

Gypsum is a naturally occurring, finely grained solid consisting primarily of calcium sulfate. It is also chemically produced as a by-product when making phosphate fertilizer and is known as phosphogypsum. Phosphogypsum and process water are pumped through pipelines to a storage area where the gypsum settles out and the water is recycled to the manufacturing plant. The stored pile of gypsum is called a gypsum stack. The U.S. Environmental Protection Agency and the Florida Department of Environmental Protection regulate the design, construction, operation and maintenance of phosphogypsum stacks.

 
Piney Point was the only phosphate chemical plant in Manatee County. No longer in operation, the plant and phosphogypsum stack is currently being reclaimed under the supervision of Florida Department of Environmental Protection.
 

Financial Responsibility/Severance Taxes

Severance tax is placed on phosphate production in the State of Florida to ensure safety of mining operations and completion of reclamation. Severance tax dollars are divided among the state’s General Revenue Fund, Nonmandatory Land Reclamation Trust Fund, Minerals Trust Fund, county governments with phosphate mining, and the Florida Institute of Phosphate Research.

 

In addition, Manatee County requires the following financial assurances be provided: liability insurance policies, general surety bond, and reclamation/wetland mitigation bond. These are held to ensure that the terms, criteria, standards or requirements of the Master Mining Plan and Operating Permit are upheld by the mining company.
 

Reclamation Statistics

Annual rate of reclamation reports are provided by the Florida Department of Environmental Protection, Bureau of Mining and Mineral Regulations. In addition, Annual Progress Reports are received from the mines providing the status of reclamation and the reclamation liability.

Research on wetland and upland reclamation continues to be conducted in order to define and modify reclamation techniques. Reclamation techniques focus on restoring wildlife habitat, hydrology, wetlands, and water resources. For further information on reclamation studies, visit the Florida Institute of Phosphate Research.