Laserfiche WebLink
AOpendfr A - Vegelmian Sampling (or 7998 <br />RESULTS <br />Revegetation success for Phase III Bond Release at the Colorado Coal Mine a'fil was evaluated <br />according to the CDMG, Guideline Regarding Selected Coal Mine Bond Release Issues, April 18, <br />1995. Vegetation parameters include: vegetative cover, production, and species diversity. <br />Transect locations are illustrated in Figures A-1 through A-4. The analysis and results of each <br />parameter are contained in the following sections. <br />VEGETATIVE COVER -1998 <br />Sample adequacy results for vegetative cover on both the reference and reclaimed areas was based <br />upon the total amount of live "hits", and is displayed in Table A-1. _. <br />Table A-1 <br />Colorado Coal Mine No. 1 <br />25-meter Vegetation Cover Point-Intercept Transects <br />Summary of Sample Adequacy Calculations <br /> Mean Vegetation Computed <br /> Cover Standard Aclual Adequate <br />Area (percent) Deviation Sample Size Sample Size <br />Reclaimed Area (June) 23.44 3.93 25 19.55 <br />Reclaimed Area (Se t.) 25.2 2.50 15 7.13 <br />Reference Area 25.07 1.96 15 4.42 <br />Analysis of vegetative cover to determine revegetation success is based upon "hits" on approved <br />species. Upon dropping annual grasses and fortis from the data for each sample area, it was <br />determined that the June sampling fell short of the 90% standard for vegetative cover on the <br />reclaimed area in relation to the reference area. Tables A-4 and A-5 display the results of the <br />samples taken on the reference and reclaimed areas in June 1998. Transect number two on the <br />reclaimed area fell in a small portion on the edge of the area invaded by cheatgrass. Due to the <br />high number of "vegetative hits" encountered on this transect, an additional ten transects were <br />I sampled to achieve sample adequacy. The transect dominated by cheatgrass influenced the <br />percentage of mean absolute cover for approved species in the reclaimed area dramatically, <br />resulting in a cover value only 87.6 percent of the cover sampled on the reference area (20.80 vs. <br />' 23.73 percent). When this particular transect is dropped from the reclaimed area data (Table A- <br />6), the mean absolute cover for approved species on the reclaimed area is 90.3 percent of the value <br />derived on the reference area (21.42 vs. 23.73 percent). Kaiser requests that this one transect be <br />I regarded as an anomaly in the data which should not be included. Comparison of approved <br />species on the reclaimed area sample in September (Table A-7) against the reference area reveal <br />that the percentage of mean absolute cover easily satisfies the 90 percent standard. The mean <br />aand0531999-057.wpd\February?b, 1999 A-7 <br />