Phosphate mining

J.C. Deriso says most people don't understand the full impact of Mosaic's plan. Workshops are one way of trying to get those questions answered from Mosaic engineers.

About two dozen people spoke out Tuesday against Mosaic's plan to mine phosphate in DeSoto County. No one told county commissioners they support the mine, proposed 90 minutes southeast of Tampa.

On Tuesday, the phosphate giant Mosaic will be represented at another in a series of public meetings on their plan to mine 18,000 acres in a county that has never been the site of a phosphate mine. We take a trip to DeSoto County, where a proposed mine would dwarf the county's largest town, Arcadia.

About 6 million gallons of water was released after a pipe broke at Mosaic's Four Corners phosphate mine.

Phosphate, the lifeblood of Florida's fertilizer industry, is gradually being mined out in the region where Polk, Hillsborough, Manatee and Hardee counties meet. Now, phosphate miners are coveting land to the south, sparking fears in an area that is a regional source of drinking water.

Members of the public can submit written comments about the proposal and attend a public meeting on Oct. 6 in Bradenton.

The Florida Department of Environmental Protection says it's to "ensure safe storage capacities" during the rainy season.

Controlled releases of treated water may begin if levels in the ponds at the former phosphate plant continue to rise, according to the Florida Department of Environmental Protection.

Once phosphate mines are used up, you can only build on them using special construction techniques that mitigate radon gas. Low levels of toxicity means they usually become preserves or cattle ranches. But several old mines in the Tampa Bay area have had a different fate.

Several environmental advocacy groups sued last year to overturn the waiver, which would have allowed the use of the slightly radioactive waste in road construction.

Three months ago, a rupture at the former Piney Point phosphate plant sent hundreds of millions of gallons of toxic water into Tampa Bay. We take a tour of one towering "gypstack" to see what's being done to keep that from happening again.

In our ongoing series on phosphate mines, WUSF reports on the long, tangled history of Florida's phosphate mines and the environment.