Over 30 million tons of phosphogypsum are produced annually in Florida, and are stockpiled indefinitely in stacks, and the total amount stored in USA is 750-1000 million tons. The possibility of using this material for road construction has been explored.
The present study was a comparison of the environmental impacts of using phosphogypsum versus conventional fill materials (e.g., from borrow pits) for road construction. A hypothetical road was considered that had the characteristics of the Veterans Expressway in northwest Hillsborough County, but one constructed using phosphogypsum instead of conventional fill. The effect of the two approaches on plant and animal communities, surface and groundwater, was considered. No significant impacts to plants and animals would be expected in connection with the use of phosphogypsum as road fill for the hypothetical highway because generation of fill material would not involve disturbance to an existing ecosystem.
The comparative treatment was extended to other aspects of the environment represented by the two roads, and the comparison matrix, which was constructed using integral numbers to depict impacts involving four categories (plant and animal communities, water quality, water resources, and air quality), favored use of phosphogypsum as roadfill.
In addition, an opinion survey was conducted to identify as many issues and concerns as possible.
Patricia M. Dooris, Dean F. Martin with Scott Emery, David E. Sumpter, Melissa Derby, Maria T. Gallardo, and Barbara B. Martin, University of South Florida. December 2000.