TAMPA — With 30 head of cattle roaming freely around a 100-acre parcel of pasture and wetlands off County Road 39, Sean and Kimberly Kelley like to keep an eye on their neighbors.
In their case, the neighbors happen to include the world's largest phosphate company.
The couple's land borders the 50,000-acre Four Corners mine. The Kelleys and other neighbors are up in arms about a Mosaic plan to use the mine in northeast Hillsborough County to dump clay — a byproduct of mining — from a new mine in Hardee County.
They say Mosaic is trying to renege on a permit it negotiated around 2002, when it agreed to refrain from dumping more clay in Hillsborough than was produced from its mining operation in the county. The fertilizer giant is asking Hillsborough County commissioners to amend that permit so it can pump clay from mined material through a 15-mile pipeline from the Ona Mine.
"The citizens don't want it," Kimberly Kelley said. "The damages Mosaic has done to us recently and our communities out there, it's not a good thing."
Mining produces a lot of clay. After draglines remove a top layer of soil, the exposed matrix — a section made up of equal part sand, clay and phosphate rock — is extracted. High pressure water guns turn it into a slurry for piping to a so-called "beneficiation" plant. There, the valuable phosphate, used in fertilizer, is extracted.
The leftover clay, still in slurry form, is piped into clay settling areas. Once the clay settles, the top layer of water is reused for mining. Over several years, most of the leftover clay dries out while some still can have the consistency of pudding, according to the Florida Industrial and Phosphate Research Institute.
About 40 percent of mined land ends up as clay resettlement areas, the institute says.
Mosaic officials said their request will not mean the creation of new clay settling areas nor the expansion of any of the 18 settling areas already permitted in Hillsborough County.
Instead, the company wants to fill existing settlement areas at Four Corners. That will make them easier to reclaim and turn into pasture and cropland, Mosaic spokesman Russell Schweiss said in an email.
If the permit is denied, then the settlement areas "will likely be best suited for cattle leases because ponds will form at the surface that would constrain other agricultural activities," he said.
Once reclaimed, though, the land could be used to expand Mosaic's agriculture business, he said.
Since Ona will not have its own beneficiation plant, the company will be pumping matrix to Four Corners and another mine in Hardee for phosphate extraction. Under the proposed new permit, some of the clay would stay there rather than getting pumped back with the sand to Ona.
Mosaic has hired land use attorney Vin Marchetti to shepherd its application through Hillsborough County. At a recent hearing, Marchetti told George Gramling, the county's phosphate mining hearing master, that the plan will extend the life of Four Corners and jobs there.
About 40 people attended the hearing last week, most hoping to sway Gramling into recommending denial of the permit amendment. He is required to issue a recommendation later this month.
The recommendation becomes part of the material that Hillsborough County commissioners will review before voting on the application in November.
Many of the people who spoke at the meeting questioned whether it is possible to fully reclaim a clay settlement area and wanted to know the chemical composition of the material.
The settlement areas are not as permeable as normal sandy soil land, so there would be a lot of water runoff, according to Manasota-88, an environmental group.
Even the Florida Industrial and Phosphate Research Institute, which has received funding from the phosphate industry, acknowledges that the settlement areas are "limited by the properties of the clay that leave the settling areas unstable."
Andrew Shafii, whose family owns an orange grove close to State Road 674 and Owens Road, said Hillsborough should not have to deal with Hardee's waste product just because Mosaic failed to accurately estimate how many clay settlement areas it would need for mining.
Shafii said mining has already affected how water flows beneath his grove. Trees have required more and more irrigation in recent years, he said.
"It's false promise after false promise," he said. "The grove is drying out; it's like a desert."