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Appendix A - Vegetation Sampling for Phase !I! Bond Release <br />46 in an attempt to achieve sample adequacy. However, the production data did not achieve sample adequacy <br />using Equation 3 on any of the four sample areas. Using the same one-tailed reverse-null t-test described <br />above, comparison of the data collected on the Irrigated Pasture and Rangeland Reclaimed Areas in 2006 <br />rejected the null hypothesis for each area. Thus, production during 2006 on the reclaimed areas was <br />successful. <br />The success standard was met for cover, production, diversity and shrub cover. The details demonstrating <br />success follow in the Results - Production 2006 section. <br />RESULTS <br />Revegetation success for Phase III Bond Release at the Golden Eagle Mine was evaluated according to <br />the CDMG, Guideline Regarding Selected Coal Mine Bond Release Issues, April 18, 1995. Vegetation <br />parameters include: vegetative cover, herbaceous production, shrub cover, and species diversity. <br />The results discussed in this section pertain to the 2005 and 2006 sampling events conducted on the AVF <br />Reference and Irrigated Pasture Reclaimed Areas and the Rangeland Reference and Reclaimed Areas. <br />Transect locations are illustrated on Figures 1, 2, 3, and 4. <br />Vegetative Cover - 2005-2006 <br />Sample size, determined in the field using all live "hits", was adequate for estimating vegetative cover on <br />each of the four sampling units in 2005 and 2006 (Table A-2).. <br />TABLE A-2. GOLDEN EAGLE MINE VEGETATION COVER POINT- <br />INTERCEPT TRANSECTS: SUMMARY OF 2005 SAMPLE ADEQUACY <br />CALCULATIONS <br />Mean Absolute Computed <br />Vegetation Cover Standard Actual Adequate <br />AYAA (%) Deviation Samvle Size Sample Size <br /> 2005 <br />AVF Reference Area 36.53 3.16 15 1.35 <br />EP Reclaimed Area 39.87 3.96 15 1.79 <br />Rangeland Reference Area 19.73 3.10 15 4.48 <br />Rangeland Reclaimed Area 32.53 2.88 15 1.41 <br /> 2006 <br />AVF Reference Area 19.50 5.64 17 14.88 <br />IP Reclaimed Area 20.93 4.89 15 9.88 <br />Ran eland Reference Area 12.80 3.36 15 12.49 <br />Rangeland Reclaimed Area 14.53 3.34 15 9.53 <br />Before evaluating if the success standard is met, the undesirable species component must be removed. <br />The Bond Release Regulations state that noxious weeds on either the state or county list should be <br />removed prior to comparing to a success standard. However, no noxious weeds on the Las Animas <br />County list occurred on the reclaimed or reference areas. Thus, as approved by CDMG, the two less <br />desirable perennial fort species, field bindweed and Canada thistle, were not removed before conducting <br />comparisons to success standards or statistical tests. The regulations also state that biennial and annual <br />species do not need to be removed unless relative cover of these species combined exceeded 10%, which <br />was true only of the rangeland reclaimed area in 2005. The excess relative cover of biennial/annual cover <br />2215 GoldenEagle PH3BOND 2006 3-10-08.doc A-6