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3.2 North Decline Mine Dewatering Svstem Area Ground cover of the North Decline Mine Dewatering System Area consisted of 13.6% live vegetation, 27.8% rock, 16.0% litter, and bare soil exposure of 42.6%. Perennial cover across the unit averaged 10.7% with annual and biennial cover averaging 2.9%. Dominant taxa were fourwing saltbush, intermediate wheatgrass (7hinopyrum intermedium), Palmer penstemon (Penstemon pa/men), greasewood (Saxzrbatus vermiculalus), and cheatgrass with 2.6%, 2.4%, 2.3%, 2.2%, and 1.6% average cover, respectively. This unit fails the revegetation success criterion of 90% of the Greasewood Reference Area value when both annual and perennial cover values are combined. It also fails when only perennial cover is compared. This failure is most likely due to the young age of the revegetation. The North Decline Mine Dewatering System Area currently passes three of the four diversity standards. There is sufficient cover of perennial cool-season grasses and perennial forbs or sub-shrubs to pass the required minimum values, and there are no planted species with greater than 70% relative cover. However, the present relative cover of perennial warm-season grasses (0%) is insufficient to pass the required minimum value (2.0%). 3.3 Roadside North Portal Facilities Ground cover of the Roadside North Portal Facilities area consisted of 60.6% live vegetation, 1.3% rock, 20.3% litter, and bare soil exposure of 17.8%. Perennial cover across the unit averaged 24.4% with annual and biennial cover averaging 36.2%. Dominant taxa were cheatgrass, forage kochia (Korhia prostrata), greasewood, annual wheatgrass (Eremapryum biticr=um), and shadscale (Atrip/ex confenYfa/ia) with 29.8%, 10.0%, 9.5%, 6.4%, and 4.7% average cover, respectively. This unit passes the revegetation success criterion of 90% of the Greasewood Reference Area value when both annual and perennial cover values are combined. It also passes when only perennial cover is compared. The Roadside North Portal Facilities area currently passes only two of the four diversity standards. There is sufficient cover of perennial forbs or sub-shrubs to pass the required minimum values, and there are no planted species with greater than 70% relative cover. However, the present relative cover of perennial warm-season grasses (0%) and perennial cool-season grasses (0.17%) is insufficient to pass the required minimum values (2.0% and 0.5%, respectively). CEDAR CREEK ASSOCIATES, INC. Page 14 SNOWCAP COAL COMPANY Revegetation Evaluation - 2006