Cost of radon-barrier systems for uranium mill tailings

Abstract

This report deals specifically with the cost of three types of radon barrier systems, earthen covers, asphalt emulsion covers, and multilayer covers, which could meet standards proposed by the Environmental Protection Agency to stabilize uranium mill tailings located primarily in the western US. In addition, the report includes a sensitivity analysis of various factors which significantly effect the overall cost of the three systems. These analyses were based on a generic disposal site. Four different 3m thick earthen covers were tested and cost an average of $27/m/sup 2/. The least expensive earthen cover cost was about $21/m/sup 2/. The asphalt cover system (6 to 7 cm of asphalt topped with 0.6m of overburden) cost about $28/m/sup 2/. The four multilayer covers averaged $57/m/sup 2/, but materials handling problems encountered during the test inflated this cost above what was anticipated and significant cost reductions should be possible. The least expensive multilayer cover cost $43/m/sup 2/. Based on the results of the Grand Junction field test we estimated the cost of covering the tailings from three high priority sites, Durango, Shiprock, and Salt Lake City (Vitro). The cost of a 3m earthen cover ranged from $18 to 33/m/sup 2/ for the sevenmore » disposal sites (two or three at each location) studied. The cost of asphalt cover systems were $23 to 28/m/sup 2/ and the multilayer cover costs were between $31 to 36/m/sup 2/. The earthen cover costs are less than the Grand Junction field test cost primarily because cover material is available at or near most of the disposal sites selected. Earthen material was imported from 6 to 10 miles for the field test. Assuming more efficienct utilization of materials significantly reduced the cost of the multilayer covers.« less