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minimum of 30 samples were collected and the data analyzed before the reverse null approach was applied to determine revegetation success. On all reclaimed sites sampled for shrub density, a minimum of 30 samples were collected and the data analyzed before the reverse null approach was applied to determine revegetation success. According to written guidance received from Mr. Dan Mathews and Ms. Sandy Brown of the DMG, if sample adequacy is achieved for both the reclaimed and reference areas, and the reclamation sample mean excceds 90% of the standard, no statisticai testing is required and success is demonstrated by direct comparison. If sample adequacy is not achieved for one or both of the reclaimed or reference areas sampled, but the reclaimed sample mean exceeds 90% of the approved standard, the reverse null hypothesis can be used. Results Field Sampling Dates. All of the data utilized in this evaluation were collected between July 8, and September 8, 2005. At the time of the field sampling, all of the plants were actively growing and it is believed that the sampling was performed close to the period of optimum plant growth, when the plant cover and production were near their peak. A total of 75 plant species were identified in the 200 cover transacts and 180 shrub density transacts sampled in this evaluation. A list of all of the plant species encountered in the field sampling efforts in this evaluation is presented in Table 1, Kerr Mine Plant Species List. Sample Adegnacy. A statistical analysis of the data collected to characterize the plant cover, production, and shrub density is presented in Table 2, Kerr Mine Sample Adequacy Calculations. This comparison documents that a sufficient number of samples were collected to describe the parameters of "allowable" plant cover, production and shrub density at the 90 percent confidence interval or until the required reverse null standard was satisfied as required by the Division's Regulations for all of the areas evaluated. Transact Locations. All of the cover, production and shrub density transacts sampled in this evaluation from the different reclamation and reference areas sampled are shown on the enclosed maps. The specific details corresponding to each reclamation area or reference area sampled will be discussed in connection with the discussion pertaining to each site. BIG SAGEBRUSH REFERENCE AREA Cover. The results obtained finm the I S randomized cover transacts sampled on this site are found in Table 3, Big Sagebrush Reference Area -Plant Cover. Total plant cover on this site averaged 35.80 percent and litter averaged 39.07 percent (Table 3, Big Sagebrush Reference Area -Plant Cover.) The 2005 data compare with an average total plant cover value of 44.9 percent found in Table 21 of the Permit. In 1996, RMR reported an average plant cover value of 46.08 percent, while in 1999, ESCO reported that the total cover on this site averaged 45.4 percent. However, comparison of their maps documents that they only sampled the east half of this reference area and not the entire footprint of the reference area as shown on Map 18, •