the time of the fluoroanhydrite sample in a second evaluation in this series a phosphogypsum sample was dehydrated at 204 u00b0 c for 3 days to soluble anhydrite iii it was then mixed with a 30 phosphatic clay slime in proportions to give 74 total solids in the mixture of which on a dry solids basis 15 was phosphatic clay solids and 85 was soluble anhydrite 1 5 7 weight proportions the soluble anhydrite immediately pulled the water out of the slime suspension resulting in a damp soil like mass after allowing the mass 39 days to hydrate and cure it was submitted to california soil test analysis the mass was compacted by astm d1557 procedures and tested for load bearing and unconfined compressive strength under astm d1883 procedures this material had an unconfined compacted compressive strength of 128 psi california bearing ratio of 56 5 of standard and 120 psi load bearing at 1 2 inch penetration showing that the material would be satisfactory as a load bearing landfill soil in another evaluation a non settling drilling mud waste slime of 21 5 suspended argillaceous solids was obtained the mud was mixed with natural anhydrite rock that contained 10 gypsum impurity which could act as a hydration accelerator for the anhydrite the rock was ground to 5100 cm 2 g blaine surface area before mixing with the slime and 80 3 parts by weight of the ground rock were blended with high viscosity agitation into 19 7 parts of the slime this resulted in an admixture containing 84 6 total solids and a weight proportion of 85 5 anhydrite 9 5 gypsum seed and 5 drilling mud solids on a dry weightbasis or 17 parts anhydrite and 1 9.