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Appendix A - Vegetation Sampling for Phase Ill Bond Release • Area Mean Weight ams Standard Deviation Actual Sample Size Computed Adequate Sam le Size Wet weig hts AVF Reference Area 57.72 28.68 30 42.43 IP Reclaimed Area 73.20 42.08 30 56.79 Rangeland Reference Area 3.28 1.60 30 41.05 Rangeland Reclaimed Area 34.19 21.44 30 67.54 Dry weights AVF Reference Area 18.67 7.93 30 31.02 IP Reclaimed Area 27.85 15.56 30 53.68 Rangeland Reference Area 1.74 1.03 30 60.00 Rangeland Reclaimed Area 12.25 6.62 30 50.16 The sample mean for herbaceous production on the Irrigated Pasture Reclaimed Area (27.85 grams dry weight) was higher that of the AVF Reference Area (18.67 grams dry weight). The Rangeland Reclaimed Area production (12.25 grams dry weight) was over six times higher than the Rangeland Reference Area (1.74 grams dry weight). Refer to Tables A-18, A-19, A-20, A-21, A-22 for production data collected in 2006. To test if these differences are significant and thus meet the success standard of greater than 90% of the production on the reference areas, the reverse null hypothesis t-test below was conducted The statistical comparison of the 2006 dry-weight production data collected on the Irrigated Pasture Reclaimed Area and the AVF Reference Area produced the following result: St 1: SE - 242.2095 + (.9 * 7.9326)2 r°` 30 30 SEsat = 3.126 95.5408 Step 2: dfs, 65.1824 + 2.8866 ) 29 29 dfsat = 40.686 The t-table value [one-tailed t-test value at the 90% confidence level (0. 1), 0=40] = 1.30 Step 3: t = 27.8467 - (.9 * 18.6733) 3.1261 t = 3.5317 Since 3.532 > 1.303, the null hypothesis of equality is rejected. The Irrigated Pasture Reclaimed Area mean exceeds 90% of the AVF Reference Area mean, and reclamation is statistically evaluated as • 2215_Go1denEag1e PH3BOND_2006 3-10-08.doc A-11