In the late 1970's, the Bureau of Mines began to examine the criteria for reestablishing vegetative cover on coal strip mine spoils near Glenrock, Wyoming. A 9-acre plot, consisting of (1) spoils covered with topsoil, (2) spoils without topsoil, and (3) spoils treated with sewage sludge, was constructed. These plots were seeded with tegmar intermediate wheatgrass (agropyron intermedium), fairway crested wheatgrass (a. Cristatum), and critana thickspike wheatgrass (a. Dasystachyum). After 5 yr, the topsoil had about 70 pct plant coverage. Revegetated spoils, without topsoil addition, averaged approximately 30 pct plant coverage, and sewage sludge- treated spoils had about 45 pct plant coverage. Comparison of grass types showed that intermediate wheatgrass produced greater surface coverages.