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term benefit. Secondly, the reclaimed area is small for a surface mine and <br />surrounded by areas dominated by trees and shrubs. Wildlife usage of the <br />reclaimed area is not jeopardized since the grassland area is immediately <br />adjacent to undisturbed areas of brush and trees providing bedding and cover. <br />Lastly, apost-mining land-use of rangeland, to support wildlife and domestic <br />grazing, is improved by increased herbaceous production with a minimal shrub <br />component. Grasses and forbs benefit from reduced competition. <br />As shown in the above table, mean values for cover and production result in <br />reasonable standards given the post-mining land use and the need for long-term <br />establishment of grasses to stabilize the site. <br />Revegetation Standards for the New Pryor Mine <br />- Cover Standard: <br />- Production Standard: <br />- Woody Stem Density <br />23% <br />237 Ibs/acre (26.6 g/mz) <br />No standard applies <br />Sample Numbers/Sample Adequacy <br />Sample adequacy calculations were made for vegetative cover of the sampled <br />reclaimed area. The following formula, accepted by the Division, was used for <br />these calculations: <br />nmin = { 2 S 2 <br />(d Xbar) <br />where <br />nm;n =minimum sample size <br />t =the "T" distribution value at the 90% confidence level <br />s =sample standard deviation <br />s2 =sample variance <br />d =percent acceptable deviation from the mean (10%) <br />Xbar =sample mean <br />Sample adequacy was not achieved for the vegetation cover parameter. Fifteen <br />cover transects were sampled. <br />Statistical Analysis <br />Separate reference areas of approximately 3 acres in size were established for <br />the two vegetation communities: pinyon-juniper and grassland. However, neither <br />reference area can be located currently and were unable to be utilized for <br />comparison purposes during the 2003 sampling period. Therefore, the data <br />