The results of a study to determine the leaching characteristics of portland cement stabilized
phosphogypsum mixtures developed for base course applications are presented. The study
used the Environmental Protection Agency Toxicity Characteristics Leaching Procedure to
investigate leaching of mixtures prepared using two cement contents, four cement types, and
two levels of relative compaction. The stabilized mixtures were cured 28 days before testing.
The results generally indicated higher levels of leaching for the stabilized mixtures for the …

BACKGROUND As a by-product of wet process phosphoric acid production, PG forms as
calcium sulphate dihydrate (CaS04• 2H20).. PG is the byproduct of the acidulation process
where sulfuric acid is reacted with phosphate rock. The reaction products-phosphoric acid
and