Study of the Fate and Transport of Calcium Sulfate (Gypsum) and Sodium Sulfate Concentrations in Shallow Soil

Tony Knafla

The knowledge gained on sulfate-salt transport will provide a guidance tool for evaluating the sulfate risk to surface soils and groundwater. This will also help the development of risk-based guidelines and remediation procedures for sulfate-impacted soils, and allow land management recommendations to prevent or remediate sulfate impacts. For instance, such recommendations could include tools to evaluate whether the use of calcium sulfate, calcium nitrate, or calcium chloride poses a greater environmental risk when treating a SAR-impacted soil, and whether the additional salinity from these salts poses a greater risk than the original SAR-impacted soil. They could also provide guidance as to when natural leaching of sulfate salts from the surface could provide a sufficiently rapid reduction of sulfate-related soil salinity.