In 1997 a dam atop a gypsum stack at a Mulberry Phosphates fertilizer plant broke, spilling 56 million gallons of acidic wastewater into the North Fork of the Alafia. Virtually everything in the 42 miles between Mulberry and Hillsborough Bay was killed. In addition to killing millions of fish and hundreds of acres of vegetation, the spill dumped 350 tons of nitrogen into Tampa Bay. Rather than pay fines, Mulberry Phosphates declared bankruptcy. Five years later, only $3.7 million was recovered from the company's insurance company. In 2002, Mosaic took over maintenance of the stack. In 2007, the cost of closing both stacks was estimated to be $48 million, which will be paid to Mosaic by the Florida Department of Environmental Protection. After closure, Mosaic will be responsible for maintaining the stacks for the next 50 years.
