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Appendix A - Pegelnliml Sampling for Phnse 1// 6aid Release the nearest 0.1 gram with the corresponding "wet" weight recorded. The tluee quadrats per tmnsect were then averaged, resulting in an individual production value per sample (transect). The "wet" weights for each sample were utilized in the field to determine that an adequate number of samples had been collected. The clipped vegetation was then oven-dried and re-weighed as a field "dry" weight. The dry weights were converted to pounds per acre for each sampled area. Fifteen transects per sampling unit were initially conducted prior to evaluation of sample adequacy. Sample adequacy for vegetative cover and herbaceous biomass production within each sampling unit was detem~ined using the Snedecor-Cochran sample adequacy formla (Equation 3). (3) l2 SZ Nnrin = (C~X )2 Where: N,,,;n = the minimum number of transects or quadrants needed, = the a = .10 t-table value for asingle-tailed t-test with n-1 degrees of freedom, sz = the sample variance, = 1 (level of precision for estimate of the mean to be within 10% of the actual mean), and, = sample mean Vegetative cover data from the transects were used to deterrine sample size adequacy. Sample size adequacy for vegetative cover was reached in the East Pit Reclaimed and Dryland Reference Areas with fifteen transects and in the Barren Ridge/Revision 1 Reclaimed Area with seventeen transects. Refer to Table A-1 for a summarization of this data. Herbaceous biomass production data from the clipped quadrats were used to determine sample size adequacy. Sample size adequacy for herbaceous production was achieved with fifteen transects in the Dryland Reference Area. Sample adequacy was not achieved in either of the reclaimed sample areas (seventeen transects in each reclaimed area) when the three quadrats per transect were averaged. Instead, each quadrat is presented in this report as an individual sample, resulting in fifty-one samples collected in each reclaimed area sampling unit. Table A-2 smnmarizes the sample adequacy data for herbaceous production plots. Per Colorado Division of Minerals and Geology guidelines on statistical evaluations (CDMG Guidelines for ConJpliance with Land Use and Vegetation Requirements for Coal Mining, November 28, 1998; Section V, A, Paragraph 2), "In some cases, vegetation conununity stmcture is such that obtaining an adequate sample for certain parameters is exceedingly difficult An upper limit of 50 samples is usually set, if appropriate sampling procedures...are followed." The sample methodology utilized to collect production samples during year 2003 qualifies as a stratified random sample in that each randomly 053-Chimney Rock_PH3BOND_2003_(Jan.22.04)a A-2