Release of radionuclides in water on reclaimed land, process water and runoff from clay settling or sand tailing areas:
The Public Health Service completed a study of the Polk County mining region in 1994 and found no pathway for human exposure to increased radioactivity via drinking water. Most of the radioactivity found in water resulting from the mining and processing of phosphate will be in the process water at the chemical processing plant with the phosphoric acid and it is not significant to public health. This water also does not go off site. It stays on the property and is recycled in the chemical processing.
Acid water that makes its way into the environment:
Requirements and regulations are in place to define how companies store their acidic water they produce in connection with the processing of phosphate rock into phosphoric acid and what they must do to neutralize and clean it before they are allowed to release it to the environment in an emergency situation. There is, however, the possibility of an accidental spill like the one that occurred in December 1997 when acidic water from a Mulberry Corporation phosphogypsum stack spilled into the Alafia River.
After the 1997 spill, a group of regulators, scientists, phosphate industry representatives, and other experts gathered for a Phosphogypsum Impoundment Technical Advisory Forum (PITAF). Since the problem occurred because Mulberry Corporation did not follow practices accepted in the industry, the group recommended engineering and operating procedures based on accepted practices and the Florida Department of Environmental Protection (DEP) adopted the procedures.
FIPR also funded research at the time to investigate the environmental impacts of using lime to neutralize acid water in such a spill. The research showed that the lime will not improve the survival of fresh water fish, but it would significantly help the saltwater fish. It may not be a perfect solution, but the FIPR study shows that liming is better than doing nothing.
Improving the quality and reducing the quantity of the process water became an even higher priority for the phosphate industry after the Florida Department of Environmental Protection (DEP) inherited three phosphogypsum stacks with full ponds when Mulberry Corporation (a chemical processing company) declared bankruptcy in January 2001. These ponds contained billions of gallons of acidic water. Two stacks are in Mulberry in Polk County, where there was a spill in 1977 and one was at Piney Point in Manatee County where a spill would endanger Bishops Harbor, a prized estuary.
DEP has maintained the water levels in the Piney Point stack by transporting water to phosphate companies willing to take it and paying for water cleaned by a reverse osmosis process. In summer 2002, Cargill Fertilizer took responsibility for the Mulberry stacks, saving DEP $30 million of the estimated $50 million to close the stack.
Piney Point, however, remains a problem (as of January 2004) and it is estimated that it will cost more than $150 million to close. In spring 2003 the DEP received an emergency permit from the EPA to barge millions of gallons of treated water from the Piney Point stack 190 miles into the Gulf of Mexico and dump it. DEP sought the permit because the reverse osmosis process being used to clean the water was not working fast enough to avoid a spill during the rainy season. Many groups including the sponge fishing industry in Tarpon Springs opposed the dumping.
At the request of the DEP and the phosphate industry, FIPR formed a new technical advisory committee (TAC) to consider solutions for process water treatment and disposal when DEP first got involved with managing and closing the stacks. Like other FIPR TACs, this group of environmental, phosphate industry, consultant, academic and DEP experts is the point of exchange for technical ideas and information.
- The TAC seeks short-term solutions for the acidic process water in the Piney Point stack and long-term solutions for reducing the volume of process water the industry generates, improving the quality of the water that is stored and finding a better way to clean it at a reasonable cost. One project that has come out of the discussions is looking at the feasibility of installing an intermediary liner in the stacks to reduce the amount of water in inventory.
- FIPR significantly reduce other research programs in 2002-2003 to set aside nearly $1 million to demonstrate a reverse osmosis process IMC had developed that could double the amount of water cleaned daily. In the fall of 2003, a partnership was formed to deal with liability issues and make the demonstration possible. In December 2003 work on a demonstration project began.
For years phosphate companies were listed as among the worst polluters in Florida in EPA’s Toxic Release Inventory. This inventory has been posted annually since the 1986 Emergency Planning and Community Right-to-Know Act of 1986 was enacted to promote emergency planning and minimize the effects of chemical accidents and to provide the public with information on releases of toxic chemicals in their communities. In 1999, as a result of a court order, EPA took phosphoric acid off its inventory of toxic chemicals.
At issue was the phosphoric acid in the cooling pond water circulated on chemical processing plant properties as part of the chemical processing of phosphate into the phosphoric acid used in fertilizer. Companies were required to report the acid in the water as a release because it circulated beyond the plant building, but unlike other chemicals on the list, it is not released to the environment. It leaves the plant and is put into the pond system to cool and is then is recycled and reused in the plant.
The water that is discharged to the environment from phosphate mining or processing land is regulated by National Pollutant Discharge Elimination System (NPDES) permits that assure it does not degrade the quality of Florida’s waters. The biggest problem is when process pond water from the chemical processing plants has to be released. There are strict regulations that require companies to neutralize the water’s acidity and reduce its phosphate and nitrogen content, and obtain an emergency permit to release the water into the environment. Metals in runoff: All soils, including those in Florida, have metals. Some metals of concern to the general public are cadmium, mercury, lead and arsenic. They are found in Florida soils and rock. They are found mostly, however, in levels low enough not t be of concern. Regulatory agencies like the U.S. EPA and the Florida Department of Environmental Protection (DEP) monitor the metals concentrations very closely and have not found a problem. In fact, researchers at the University of Florida have found phosphate rock to be an effective amendment to immobilize metals like lead in soils so that they are not available for uptake in excessive amounts by animals and plants.
The DEP had FIPR recently assess the metals connected to a test road built with phosphogypsum more than 20 years ago. The question was whether metals like cadmium and arsenic being found in nearby wells came from the phosphogypsum used in the road base. A FIPR research project evaluated a long list of metals the DEP wanted tested and found that the levels in phosphogypsum were acceptable. The trace amounts of metals in the phosphogypsum did not migrate to groundwater.
Metals have also not been found to be a problem in runoff from phosphogypsum stacks. DEP studies have found that even metals associated with the process water in the stacks are not above levels that meet drinking water standards.