RI 8075 Electrokinetic Densification of Hydraulic Backfill-A Field Test

Hydraulic backfill consisting of siliceous mill tailings was successfully dewatered and consolidated by electrokinetics in a field test conducted by the Bureau of Mines at the Star mine, Burke, Idaho. A stope at the 2,000-foot level was filled in such a way that slimes and coarse sand were retained in the scope. Following settlement of solids and decant of surface water, direct current applied between buried electrodes created a firm, dense material in approximately 3 hours. This rapid densification of fine-grained material demonstrated the utility of this method and suggests other applications, particularly in the control of slime deposits that cause serious problems in many deep mines.