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First miners used shovels and picks, than later they used mule-drawn scrappers and wagons. In 20th century they started to use better tools like steam tools and draglines. Quite a hard way to mine! Today, modern technology helps mining companies get to the deeper phosphate and get more phosphate out. Mining phosphate is a complicated process.
Before they start mining, mining companies have to find out if the land is good for mining. They have to find out is there enough phosphate, how deep it is, where is it located, and can it be mined. They do core sampling. This is where the insert core sampling equipment in the ground to figure out if there is mineable phosphate.
The next step is to make a reclamation plan. In 1975, the state of Florida made a law. They made all mining companies make a reclamation plan. This means that the companies will mine and after they are done they will return the environment to what it was before mining or better.
Next, they have to prepare land for mining. They have to clear it up. Than they bring the dragline in. Dragline is the huge crane. It has a huge bucket that can hold 45 to 60 cubic feet of dirt. Dragline bucket is so large it can hold a truck!
The dragline first gets into the overburden. Overburden is the top part of soil. There is no phosphate in it. So, the mining companies get rid of it. Overburden is 15 to 30 feet deep. The overburden is dumped on the side of the pit. When the mining is done it will be used to reclaim the land.
Under the overburden is the "good" stuff - it is in the matrix. Matrix is made of three parts- sand, clay and phosphate rock. There is an equal part of each in the matrix. The matrix is dumped in the pit. Than they bring water guns and mix matrix with the water until it's muddy. This is called slurry. Slurry goes to the beneficiation plant. In this plant phosphate will be separated from clay and sand.
THIS IS HOW MINE OPERATES
( Thanks to Ms. Mikkola for Cargill Mine Pictures)
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