2012-09-06_REPORT - C1980006 (2)

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The locations of the 15 cover transects sampled on this site are shown on Map 5, 1999 Reclamation - Vegetation Transect Location Map. The sample adequacy calculations in Table 2, Kerr Mine Sample Adequacy Calculations, document that the number of transects required to characterize the plant cover on this site at the 90 percent confidence interval was 10.2 transects. When ME sampled this site in 2005, they reported that total plant cover averaged 33.27 percent and litter cover averaged 27.27 percent. Table 6, 1996 Reclamation - Plant Cover, documents that the "total plant cover" on this reclaimed site averaged 33.94 percent. Since this "total plant cover" value exceeds the total plant cover value of 32.13 percent obtained from the sampling of the Alkali Sagebrush Reference Area, this value (32.13 %), would be the corresponding revegetation success standard for the 1999 Reclamation site. Since sample adequacy was achieved for plant cover sampling on both the reference area and this reclaimed site, it can be concluded by direct comparison that the "total plant cover" for the 1999 Reclamation Block satisfies the revegetation success standard with respect to "total plant cover." Production. The results of the 30 production transects sampled on this area are summarized in Table 7, 1999 Reclamation - Production. This table shows that the average total herbaceous forage production was found to be 30.81 g/1 /4 m or 1,098.1 pounds or air -dry forage per acre. Perennial grasses contributed 29.70 g/1 /4 m or 96.40 percent of the herbaceous forage produced on this area. Perennial forbs, contributed 1.10 g/ 1 A m or 3.60 percent of the herbaceous forage production on this area. The revegetation forage production standard for this area is 7.40 g/1 /4m or 263.7 pounds of air - dry forage per acre. Since this site averaged 53.88 g/1 /4m or 1,920.2 pounds or air -dry forage per acre, it appears that this area satisfies the revegetation success standard with respect to total herbaceous forage production. In 2005, RVIE reported that total herbaceous forage production on the 1999 Reclamation site averaged 53.88 g/1 /4m' or 1,920.3 pounds of air -dry forage per acre. Perennial grasses contributed 49.61 g/1 /4m' or 92.07 percent of the total forage production and perennial forbs contributed 1.57 g/1 /4m or 7.93 percent of the total forage production The locations of the 30 production transects sampled on this site are shown on Map 4, 1995 & 1999 Reclamation - Vegetation Transect Location Map. The sample adequacy calculations in Table 2, Kerr Mine Sample Adequacy Calculations, document that the number of samples required to describe this site at the 90 percent confidence interval was 107.6 transects. Using the reverse null statistical approach on the production data obtained from this site, yields a t, value of 6.0669. Since this t, value is greater than the table t value at an alpha error probability level of 0.20 which corresponds to a t value of 0.854, H is rejected and the revegetation production on this site is considered successful, using the DRMS regulations. However, since the production on the reclaimed site exceeds the revegetation success standard, sample adequacy was achieved with 30 transects.