View of the mill tailings pile at the MOAB site, looking east.
The day crew at the Crescent Junction Disposal site stands in front of the container carrying the 4 millionth ton of mill tailings from the Moab site.
Moab, UT - One quarter of the uranium mill tailings pile located in Moab, Utah, has been relocated to the Crescent Junction, Utah, site for permanent disposal. Four million tons of the total 16 million tons has been relocated under the Uranium Mill Tailings Remedial Action Project managed by the U.S. Department of Energy (DOE).
A little over 2 years ago, Remedial Action Contractor EnergySolutions began shipping the tailings by rail away from their current location next to the Colorado River, to Crescent Junction 30 miles north. The tailings are remains from processing uranium ore for national defense programs from 1956 to 1984.
The project received a boost in funding from the American Recovery and Reinvestment Act that increased the weekly train shipments from four to 10. “To be a quarter of the way done in about 2 years was unthinkable when we first started shipping in April 2009,” said Federal Project Director Donald Metzler. Once the Recovery Act funding is depleted by the end of June, the project will continue shipping tailings using funds from annual appropriations.
At Crescent Junction, the tailings are placed in a disposal cell that is excavated 25 feet below grade and will cover about 250 acres at completion. The tailings material in the cell is a total of 50 feet thick, reaching 25 feet aboveground. The tailings are then capped with a 10-foot-thick, multi-layered cover composed of native soils and rock. Final cover layers have been placed on the 10-acre portion of the cell that has met the final grade for tailings material. The rock for the biointrusion and erosion protection layers is being quarried to meet U.S. Nuclear Regulatory Commission specifications for durability, and is hauled to the site from a quarry 70 miles away. All other cover layers come from material excavated on-site at Crescent Junction.
Through use of extraction and freshwater injection, the project continues to protect the Colorado River that borders the Moab site by minimizing the discharge of elevated concentrations of ammonia and uranium. These ground water contaminants, which resulted from the processing of uranium ore, can be harmful to young-of-year fish that use the backwater channels as habitat during late summer.
This spring, runoff from above-average snowfall caused the river to crest above flood stage and overtop the riverbank onto the Moab site. Most of this area had contained contaminated soils until the past 1½ years when the area was remediated. The river level peaked on June 10 and has started to recede. A series of berms prevented the river water from reaching the tailings pile.
Thanks to the additional funding received under the Recovery Act, more people have been employed, the river continues to be protected, and the aesthetics of the area are being enhanced.
For more information, visit Moab Project website at www.gjem.energy.gov/moab.