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• Sample sites were located in the field through compass triangulation and pacing from known landmarks. Figure 1 illustrates the location of the reclaimed areas and sample point locations. In the azeas reclaimed in 1985, 1986, and 1987, a qualitative evaluation of revegetation success was undertaken this year. These areas were previously monitored (since 1994) and after successfully meeting revegetation success criteria, were released from the Phase II Lability requirements by the Colorado Division of Minerals and Geology August 11, 1998. This year, qualitative evaluation of these azeas includes estimating vegetative cover, herbaceous production, and identifying the dominant plant species. Any locations or trends in vegetation development that required attention were also noted. The Osgood sand reference area was measured and mapped in the field in 1994 by Savage and Savage staff, and this scaled drawing of the reference area was used. On the scaled drawing, a Cartesian coordinate grid (50x50 feet) was established. Computer generated random numbers were used to establish a pool of x,y coordinates. Ten vegetation cover and fifteen herbaceous production sample locations were randomly established for the reference area. Sample sites were located in the field through compass triangulation and pacing from known landmarks. Figure 2 illustrates sample point locations at the Osgood sand reference area. FIELD SAMPLING • Timing Field investigation was undertaken during the period July 27-30, 1999. This time period coincided with anthesis and maximum development of the majority of plant species found in both the native vegetation community (Osgood sand reference area) and the reclaimed areas at the mine site to be evaluated. The Keenesburg area experienced a very wet spring and eazly summer precipitation regime based on mine site records. Total precipitation for ]999 at the mine site was 11.67 inches as of the end of July. This represents a 35.2 percent positive deviation from the January-July average of 8.63 inches. Vegetation Cover Vegetation cover was estimated by the use of the point-intercept method. An ocular point frame (ESCO Associates) was used to minimize instrument error and maximize precision and observer accuracy. Cover transects were 25 meters in length, with two sample data points collected at 1.0 meter intervals along the transect on opposite sides of the transect centerline, 1.5m apart. Transect dvection was established randomly through the use of a spinner. In no event were transects allowed to extend within ten feet of reference or revegetated area boundaries to minimize impacts from "edge effect." For statistical purposes, each cover transect (comprising 50 data points) served as a • sample unit. Data points recorded the first vertical "hit" on vegetation (above or below -3-