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i• • ~~ 2.2.2 EP033 EP033 is comprised of 12.0 acres of moderately sloping revegetation that has a predominately easterly aspect. This unit was seeded in 1998 and therefore, has undergone seven growing seasons prior to sampling in 2005. A total of 33 plant taxa were observed in the unit (see Table AB-i). Current annual production across the unit averaged 2,422 pounds per acre in 2005 with perennial grasses and annual grasses the dominant categories (see Figure 2}. Ground cover in EP033 consisted of 66.3% live vegetation, 1.4% rock, 20.6% litter, and bare soil exposure of 11.8%. Perennial cover across the unit averaged 52.8% with annual and biennial cover averaging 13.5%. The dominant taxa were Siberian wheatgrass, thickspike wheatgrass, streambank wheatgrass, cheatgrass and cicer milkvetch with 11.7%, 11.6%, 11.2%, 10.1%, and 3.7% average cover, respectively. Woody plant density was determined from 20 belt transects. Density (Table 2) totaled 6 young and mature stems per acre with big sagebrush the dominant woody plant. With regard to diversity, EP033 exhibited 5 perennial grasses and 1 perennial forb with between 3% and 50% relative cover. Mae 3 - EPo33 Vpetati0n Sampl~p Point LWtlwu- MOS - . 1W:~,mwm~p~M .~.. ~, ..-------- Unit EP033 currently passes the bond release diversity standard of 3 perennial grasses and 1 perennial forb with between 3% and 50% relative cover, This unit also easily passes both the cover and production bond release comparisons to the reference areas (see Charts 3 and 5). 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 Canada thistle was observed in seve2l locations. There are several small patches of annual bromes scattered throughout the unit. Although these bromes currently represent only 12.3% 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. At present, EP033 is a good example of an improved pasture grassland community that would contribute to the local system as foraging habitat for wildlife (especially elk), as well as provide a variety of management opportunities for livestock grazing. Kennecott Energy Co. / Colowyo Mine Page 13 ReVegetation Monitoring - 2005