As part of its mission to reduce pollution associated with mineral production, the Bureau of Mines is developing a dewatering technique for phosphatic clay waste that uses a flocculant, polyethylene oxide (peo). This flocculant forms strong, stable flocs, which can be partially dewatered on a static screen and dewatered further on a rotary screen. Using this technique, a field test unit (ftu) was operated at a nominal 100 gal/min. Consolidated phosphatic clay material containing 20 percent solids was produced when feed slurries of 3 percent solids were treated with 0.69 Pound of peo per ton of feed solids. Pit and column tests indicated that the peo- treated material continued to dewater; compacted products containing 40 percent solids were obtained after 45 days.