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1 ntrod uction <br />The Division of Minerals and Geology collected vegetation data on the Rimrock Mine on June <br />23 and 24, 2003, in support of an application for release of liability associated with CDMG <br />permit C-1989-074. The Rimrock Mine is located in Las Animas County. Rimrock Mine was a <br />surface coal mine that commenced operations in November, 1991, and initiated reclamation in <br />1992. The permit area encompasses 38.7 acres. Only 19.6 acres were disturbed by the <br />mining operation and were included in the vegetation sampling protocol. Vegetation sampling <br />was conducted in accordance with Colorado Mined Land Reclamation Board Surface Coal <br />Mining Rules 2.04.10 and 4.15, accepted bond release guidelines, and current botanical and <br />ecological methods. <br />II. Methods <br />Timing <br />Field sampling was conducted on June 23 and 24, 2003 by CDMG personnel. Timing of the <br />sampling was scheduled to coincide with active biomass production and vegetation <br />identification of both warm season and cool season species. In 2002, Colorado experienced a <br />serious drought. 2003 has seen a moderate recovery in precipitation levels for the first 6 <br />months of the year. Upon arrival at the site, qualitative estimates indicated vegetation on the <br />reclaimed mine site had responded favorably to more normal precipitation levels. Domestic <br />grazing was not conducted on the reclaimed area during the 2003 growing season, the 10~h <br />year following reseeding. <br />Sampling Design <br />Prior to data collection on the reclaimed mine site, the permit document, permit revisions, prior <br />sampling data, and applicable maps were reviewed to evaluate topography, sampling parcels, <br />revegetation methods and timing, and applicable revegetation standards. Vegetative data <br />planned for collection included live vegetative cover, herbaceous production, and woody stem <br />density data. <br />Vegetative Cover <br />Vegetation cover was estimated by the use of the point-intercept method. A ten-point laser <br />point frame was used. Ten laser points are spaced every 10 cm along a 1 meter bar, which is <br />mounted on a tripod. The lasers project vertically down to the ground surface. The point at <br />which the laser was first intercepted was recorded as one of the following: live vegetative <br />material (identified to genus and species), litter, rock, or bare ground. Shrubs were not <br />counted as a component of the herbaceous cover data. <br />A 1:1200 scale (1 inch=100 ft.) map of the permit area (permit map "Exhibit KK-1") was used to <br />delineate the sampling area consisting of all reclaimed areas within the permit area. A <br />Cartesian grid was overlaid upon the reclaimed areas and sample sites were established using <br />a randomization computer program. Computer-generated random numbers were used to <br />establish a pool of (x,y) coordinates. Fifteen random locations for transect starting points were <br />