The dragline is "stripping" the overburden to expose the "matrix" the mixture containing sand, clay and the phosphate rock.
Phosphate mining severely alters the landscape's natural ability to filter rainwater. Alterations caused by mining either cause the water to go through the surface water system too fast, or not at all.
During the mining process, water at the surface is held on the mine property. This has to happen or the sand, silt, clay, pollutants and other mining by-products would make their way downstream, reducing water quality, potentially all the way to Charlotte Harbor. This could arguably be called a "temporary" problem even though the mining might go on for years.
Of greater concern is reclamation — the process of returning the land to its "natural" state after mining. Typically with reclamation, young vegetation replaces mature growth. As a result the ecosystems just don't function like they used to. When rain falls, instead of meandering through natural flow ways and vegetation, it pools in ponds that didn't exist naturally or it runs off land that has been "restored' with saplings and new growth. As a consequence, the timing, quantity and quality of water flows are changed. Water either flows too fast through the system to adequately filter or it pools in places that don't allow it to enter the natural system.
Horse Creek near Solomon's Castle, a popular tourist stop.
Of course, mining isn't the only thing that affects water quality. Wastewater discharges, pollution from communities, fertilizers and pesticides from agriculture and from our own yards can also harm water quality, but nothing has the potential to affect water quality so profoundly, continuously and extensively than the strip mining necessary to produce phosphate.
To see the potential impacts of phosphate mining on water quality, we need only look at Hillsborough and Polk counties. Polk is part of the upper Peace River system so it provides a particularly good example of phosphate mining's risk to water quality. Even without industrial spills, water quality in much of the area is poor. Hillsborough County is a tiny part of the Peace River watershed, but the direct consequences of phosphate mining are clear there. From the moonscapes left behind to the accidental spills, which have had a real impact on Tampa Bay, Hillsborough and Polk Counties will pay for phosphate mining long after the industry has moved further into the Peace River watershed.
Phosphorus levels in the Peace River are already among the highest in the state. Horse Creek used to be a standard for water quality monitoring. It's already declining. What will phosphate mining do to water quality? We really don't know all the potential consequences because phosphate mining companies have resisted revealing their plans. We know that the present standards for reclamation don't protect water quality, and we know who pays when problems are discovered–and it's not the phosphate industry.