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• reclaimed azeas as outlined in the Permit, contain standards as to the number of perennial grass species growing on the reclaimed areas to ensure that a monoculture of a single plant or a few plants does not dominate the reclaimed areas. As described on revised page 2.05.4-27 of the Southfield Mine Permit, submitted in connection with Minor Revision 48, the species diversity standard requires that for all revegetated azeas at the Southfield Mine site, the reclaimed plant community shall be composed of at least four dominant species comprising no more than 80 percent of the total relative percent cover. Warm season grasses "shall comprise at least 50 percent of the total plant cover composition." Historical Data Since no reference area sampling was conducted in this evaluation, and to properly evaluate vegetation trends over time, we compared data previously collected from the Grassland Reference Area data collected at the Southfield Mine. In sampling conducted in the fall of 1987, total plant cover on the Grassland Reference Area was detemuned to equal 41.00 percent. Total production was detemuned to average 74.08 grams / mz or 660.1 pounds of air dry forage per acre. Woody plant density was calculated to average 3.2 woody plants per 100 mz or 129.5 woody plants per acre. Sampling of the Grassland Reference Area in August of 1997 resulted in total plant cover of 40.00 percent, production averaged 32.55 g/1/4 m2 or 1,160 pounds of air dry forage per acre. These data aze included only to document historic trends and not in any way to satisfy any of the required bond release vegetation sampling requirements but are used to make relative comparisons regazding revegetation success. Using these historic Grassland Reference Area data, the revegetauon success standazd would be approximately 40.50 percent total plant cover and production would average 25.54 g/1/4 mZ or 910 pounds of air dry forage per acre. Statistical Analysis of Data. As required by the Division's current regulations, it is not necessary to achieve sample adequacy for interim reclamation monitoring. However, the DRMS guidelines recommend the sampling of at least 15 transects for cover and 30 transects for production and shrub density were employed in this evaluation, Therefore, all of the data collected in taus evaluation were analyzed for sample adequacy in order to determine whether the Division's requirements had been satisfied. The new sample adequacy formula contained in the revised regulations was used, wherein a precision of 0.10 was used for cover and production and 0.15 for shrub density. Transplanted Shrub Survival. In April and May of 2004, EFCI contracted with the Colorado State Forest Service to plant 12 shmb clumps containing some 1,843 trees and shrubs on different portions of the Vento Reclamation. In connection with this revegetauon monitoring effort, the Division directed EFCI to monitor a sufficient number of these shrub clumps and determine the overall successfulness of the shrub and tree establishment efforts. In this effort a total of four of 12 shrub clumps were measured, identified as Shrub Clumps IB, 2B, 2E and 3C. On these four shrub clumps a total of six different trees and shrubs were planted, including Ponderosa Pine, Rocky Mountain Juniper, Skunkbrush Sumac, Mountain Mahogany, Pinyon Pine and Eastern Red Cedaz. Based upon discussions with EFCI we decided to sample four of the 12 shrub clumps, corresponding to the areas in the Vento Reclamation reseeded in October