TAMPA — A phosphate mine in Hillsborough County will be used as a dumping ground for up to 28 million tons of clay — a by-product of mining — from a new Mosaic operation in Hardee County.
Hillsborough County Commissioners on Wednesday voted 4-2 in favor of the controversial request by Mosaic to dump clay from its Ona Mine into the Four Corners Mine in southeast Hillsborough County. It was one of the board's last acts before two new commissioners are sworn in next week.
The vote reverses a provision agreed in 2002 that there would not be more clay dumped in Hillsborough than was produced from phosphate operations inside the county.
Commissioners did attach some strings to their approval.
Mosaic must report annually how much clay it has dumped at Four Corners and must pay for an independent firm to monitor water quality at so-called "clay-settling'' areas where the material will be dumped. And commissioners placed a five-year limit on their approval, although Mosaic could apply to extend that through 2029.
Mosaic's plans have alarmed many of the mine's neighbors who fear it will harm water quality in the area and lead to more dust and disruption on their roads.
"Find somewhere else to put Hardee County sludge because we don't' want it," said Kimberly Kelley, who along with her husband Sean Kelley keeps about 30 head of cattle on a 100-acre parcel of pasture and wetlands off County Road 39.
Neighbors also are worried the county has set a precedent for further requests from Mosaic to dump other mining by-products in Hillsborough.
"The only ones who benefit from approving this permit are Mosaic and Hardee County," said Gloria Welch, who lives in a senior community near Four Corners. "Hillsborough County gets nothing."
That is disputed by Mosaic officials.
Four Corners is approaching the end of its operational life as a mine but Mosaic still has 550 employees working there and another 100 contractors. Those jobs will continue while the mine is still open, said said Mosaic spokesman Russell Schweiss.
"It is our largest mine and has the largest workforce of any of our mining operations so, as long as it is operating, it is a significant source of revenue for the county whether we are mining rock from the county or not," he said.
Mining produces a lot of clay. After drag-lines remove a top layer of soil, the exposed matrix — a section made up of equal parts sand, clay and phosphate rock — is extracted. High-pressure water guns turn it into a slurry for piping to a so-called "beneficiation" plant where the valuable phosphate is extracted.
Some slurry from some of the Ona mine will be piped through a 15-mile pipeline to the beneficiation plant at Four Corners. Instead of leftover clay going back to Ona, it will stay at the Hillsborough mine.
Schweiss said that does not mean Mosaic will build new clay areas nor expand any of the 18 already permitted in Hillsborough County. But it does want to take advantage of unused capacity in areas at Four Corners. Fully filled areas can be reclaimed more successfully than partially filled ones that pool water, Schweiss said.
About 40 percent of mined land ends up as clay resettlement areas, according to the Florida Industrial and Phosphate Research Institute. Its research found that the settlement areas are "limited by the properties of the clay that leave the settling areas unstable."
Once the Hillsborough clay areas are full, Mosaic is required by law to reclaim them. They may be suitable for growing eucalyptus trees or pasture land to keep cattle, officials said.
That is disputed by some environmentalists. Rachael Curran, an attorney for the non-profit Center for Biological Diversity, said the result will be barren wastelands.
"It's laughable that Mosaic is claiming that dumping more of this radioactive clay into partially filled slime ponds will somehow magically create better conditions for reclaiming farmland," she said in a statement. "Hillsborough commissioners should be ashamed of turning their backs on the voters they serve and the future health of the county."
County Commissioners Sandy Murman and Ken Hagan were joined by outgoing commissioners Victor Crist and Al Higginbotham in voting for the new permit. They also rejected a request by Pat Kemp to delay the vote until the county's only hydrologist, Mike Stephenson, could testify. He is currently on leave.
That delay would have meant that the permit would be considered by the newly elected board, which is now majority Democrat.
Mosaic is a regular donor to the political campaigns of commissioners and candidates for office, as is Vincent "Vin" Marchetti, the attorney hired by the fertilizer giant to shepherd its application through public hearings.
Since 2014, the fertilizer giant and the land-use attorney have given a combined $38,000 to commissioners and candidates.
Kemp, a Democrat, was joined by Republican Stacy White in opposing the permit.
White, whose district includes the Four Corners Mine, said Mosaic has been a good community partner but that neighbors of the 50,000-acre mine have put up with enough disruption. Mining operations there are scheduled to wind down in the next two years and people's lives will get back to normal, he said.
But the clay-dumping operation will keep the mine open for years to come.
"It will be Hardee County that gets the jobs and the revenue at the expense of our citizens taking the undesirable by-products," White said.
Times Senior Researcher John Martin contributed to this story. Contact Christopher O'Donnell at email@example.com or Follow @codonnell_Times.