Phosphogypsum Stockpiles

Evaluation of Radium and Toxic Element Leaching Characteristics of Florida Phosphogypsum Stockpiles... 

REFERENCE May A. and Sweeney. J. W.. Evaluation of Radium and Toxk Element Leaching Characteristics of Florida Phosphogypsum Stockpiles/ The Chemistry and Technology of Gypsum, ASTM STP 86 , R. A. Kuntze. Ed.. American Society for Testing and Materials. 1984. pp. 140-159. 

The first phase of the Bureau s research [1 ] showed that phosphogypsum was not corrosive by Environmental Protection Agency (EPA) criteria. The study also presented evidence that phosphogypsum would not be toxic by EPA criteria and that trace elements and radium would not be leached from the stockpiles. These conclusions were obtained from statistical analyses of extensive quantities of spectrographic and radiological data. More direct confirmation of these conclusions was needed to decisively answer the question of leaching of toxic elements and radium from phosphogypsum stockpiles. 

To help explain the results of this study and to aid in predicting the future stability of phosphogypsum stockpiles, the hydrology associated with the piles and the solubility and absorption of trace elements and radium were considered. How well the objectives of this investigation were met is also briefly considered. 

These slurry areas make up only a small part of the phosphogypsum stockpile areas, and most of the remaining pile areas are fairly dry. Leaching in the settled portion of the pile would be due to rainwater passing downward through the pile. 

Phosphogypsum stockpiles in Florida are not hazardous toxic wastes. 

Trace elements are not leached from phosphogypsum stockpiles. 

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