106 CWA Project: UMTRA
The EPAhas funded WREQC to evaluate the Uranium Mill Tailing Remedial Action (UMTRA) site down in the Arapaho Area near Riverton, Wyoming, where in the 1960 into the 1970s the Department of Energy (DOE) operated a Uranium Plant which separated the uranium from the gravel and made a product called "Yellow Cake". The results of this work left behind 900,000 cubic yards of mill tailings which was radioactive. The Tribes in 1988 through the UMTRA Program asked the DOE to remove all the mill tailings from the Reservation. This was done, and the majority of the mill tailings was hauled back to the Gas Hills open pit mines where it came from. The removal of the mill tailings was not complete, the DOE only removed approximately seven feet of top soil under the huge pile and did not go deep enough to capture all radioactive materials. The recommended depth to excavate under the mill tailings was seventeen feet....this was not done. The results of this act, the radioactive contaminated soils that should have been excavated laid exposed to the natural seepage's of the precipitation carried the radioactive elements into the ground thereby contaminating the groundwater. The radioactive contaminants soaked into the soils to a depth of 30', 45', and 60' feet deep.
