Salt disposal: Paradox Basin, Utah

This report presents the findings of a study conducted for the National Waste Terminal Storage (NWTS) Program. Permanent disposal options are examined for salt resulting from the excavation of a waste repository in the bedded salt deposits of the Paradox Basin of southeastern Utah. The study is based on a repository salt backfill compaction of 60% of the original density which leaves a total of 8 million tons of 95% pure salt to be disposed of over a 30-year period. The feasibility, impacts, and mitigation methods are examined for five options: commercial disposal, permanent onsite surface disposal, permanent offsite disposal, deepwell injection, and ocean and Great Salt Lake disposal. The study concludes the following: Commercial marketing of all repository salt would require a subsidy for transportation to major salt markets. Permanent onsite surface storage is both economically and technically feasible. Permanent offsite disposal is technically feasible but would incur additional transportation costs. Selection of an offsite location would provide a means of mitigating impacts associated with surface storage at the repository site. Deepwell injection is an attractive disposal method; however, the large water requirement, high cost of development, and poor performance of similar operating brine disposal wells eliminates this option from consideration as the primary means of disposal for the Paradox Basin. Ocean disposal is expensive because of high transportation cost. Also, regulatory approval is unlikely. Ocean disposal should be eliminated from further consideration in the Paradox Basin. Great Salt Lake disposal appears to be technically feasible. Great Salt Lake disposal would require state approval and would incur substantial costs for salt transportation. Permanent onsite disposal is the least expensive method for disposal of all repository salt