History, current status, and physical stability of sodium sulfate disposal facility, Owens Lake, California

A characterization study of Umetco Minerals Corporation’s inactive Sodium Sulfate Disposal Facility in Owens Lake, California, was performed by Shepherd Miller, Inc. as part of a study for determining details of a final closure plan for the site. This paper presents an overview of the Owens Valley and describes the regional geology, surface hydrology, subsurface hydrology, salt crusts, and evaporation in the area of the disposal facility. The history of the disposal facility is presented, as well as the results of the investigation of the physical stability of the tailings deposit. The tailings deposit was determined to be physically unstable due to phase changes of the sodium sulfate tailings. Two companion papers are introduced, one regarding ground water and chemical transport, and the other regarding a geochemical investigation. The companion papers show that the disposal facility has had only a minor effect on the ground water quality. Reclamation options are currently being considered for the site.