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u 2.2.3 EP038 EP038 is comprised of 4.1 acres of moderately sloping revegetation that has a predominately easterly aspect. This unit was seeded in 2001 and therefore, has undergone four growing seasons prior to sampling in 2005. A total of 29 plant taxa were observed in the unit (see Table AB-1). Ground cover in EP038 consisted of 65.3% live vegetation, 0.1% rock, 18.7% litter, and bare soil exposure of 15.9%. Perennial cover across the unit averaged 37.1% with annual and biennia! cover averaging 27.4%. The dominant taxa were cheatgrass, thickspike wheatgrass, titer milkvetch, slender wheatgrass (Agropyron trachycaulum), Siberian wheatgrass, and Russian wildrye (E/ymus junceus) with 22.3°h, 6.5%, 6.1%, 6.0%, 4.9% and 4.1% average cover, respectively. Woody plant density was determined from 15 belt transects. Density (Table 2) totaled 46 young and mature stems per acre with four-wing sa(tbush (Atrip/ex canescens) the dominant woody plant. With regard to diversity, EP038 exhibited 5 perennial grasses and 2 perennialforbs with between 3% and 50% relative cover. veoeruon snmgi~p vovrc ~unam~zoos '~~' • zWS Samgew vum a.a.ww.mr~ .._.____ GM S[e: llvv lva o n n im ~n .w Unit EP038 currently passes the bond release diversity standard of 3 perennial grasses and 1 perennial forb with between 3% and 50% relative cover. This unit should readily pass production bond release comparison to the reference areas, but presently does not pass cover comparisons (see Chart 3). Also, this unit does not presently meet the woody plant density standard of 90% of 1000 stems per acre and will probably not meet this in the foreseeable future due to the heavy competitive grass cover. See Appendix AA -Section 7.3 for a discussion on options and recommendations with regard to woody plant density. Noxious weeds appear to be controlled in this unit, however a large population of musk thistle was observed in one location. There are several large patches of annual bromes scattered throughout the unit. Although these bromes currently represent only 22.3% cover, these patches should be monitored/mapped to determine if they are expanding or shrinking. If monitoring reveals expansion, use of the herbicide Plateau is recommended in conjunction with spot reseeding. It is possible this activity could occur as a normal range management practice without resetting the clock. CDMG would have to be consulted for specific allowances unless such are currently stated in Colowyo's permit. Unit EP038 exhibits good diversity and perennial cover levels for four year old revegetation. Monitoring and control of the musk thistle and annual brome patches is recommended. Kennecott Energy Co. / Colowyo Mine Page 14 Revegetation Monitoring - 2005