Bone Valley
The Bone Valley is a region of central Florida, encompassing portions of present-day Hardee, Hillsborough, Manatee, and Polk counties, in which phosphate is mined for use in the production of agricultural fertilizer.
Large walking draglines, operating twenty-four hours a day in surface mines, excavate raw pebble phosphate mixed with clay and sand (known as matrix).
The matrix is then dropped into a pit where it is mixed with water to create a slurry, which is then pumped through miles of large steel pipes to washing plants.
These plants crush, sift, and separate the phosphate from the sand, clay, and other materials, and mix in more water to create a granular rock termed wetrock.
Waste byproducts are stored in large phosphogypsum stacks and settling ponds, often hundreds of acres in size, and up to 200 feet (60.96 m) tall.
[1] Phosphate processing produces significant amounts of silicon tetrafluoride and hydrogen fluoride gas, which must be treated by filtering through special scrubbers.
[2] Much of the final product (known within the industry as 'dryrock') is transported by rail to facilities along Tampa Bay, where they are transloaded onto ships destined for countries such as China.
When the narrow gauge[4] Florida Southern Railway reached Arcadia in 1886, it was a sleepy little town and the builders paused only briefly before pushing the railroad south to Punta Gorda.
Here he found and shipped to the Smithsonian Institution nine barrels of prehistoric fossils from the sand bars prevalent on the lower Peace River.
Moorhead of Pennsylvania, who had also learned about the deposits from Captain LeBaron, but not the secret of their location, traveled to Arcadia where he stumbled onto the famous sand bars.
The first shipment of Florida phosphate was made in May 1888 when the first ten car loads were dispatched to Scott's Fertilizer Works in Atlanta, Georgia.
Moorhead returned to Pennsylvania, where he developed a phosphate mine in Juniata County, PA and formed the narrow gauge Tuscarora Valley Railroad.
The railroad served various load-outs along the river, where the barges carrying pebble were unloaded into ore cars for the journey to the drying plants at Arcadia and Hull.
Like the Comer & Hull operations, the ore was hauled to the drying plant at Arcadia where it was loaded into the narrow gauge boxcars of the Florida Southern.
In the early years, phosphate from the Peace River area was barged to Punta Gorda, or shipped by rail to Port Tampa.
Many plants and mines were served by both railroads, such as the Ridgewood facility located at Bartow, and the massive Pierce complex south of Mulberry.
Cargill Crop Nutrition, who owned the stack, added lime into the affected areas in an attempt to neutralize the highly-acidic runoff.
[6] Most recently in March 2021, millions of gallons of industrial wastewater from the former Piney Point fertilizer processing plant in Manatee County was released into Tampa Bay in response to the facility’s second leak in a decade.
Environmental advocates are concerned about the effect that releasing nutrient-rich water once again will have on wildlife in Tampa Bay, and if red tide blooms, over the potential for economic impact.
