2009-11-02_REVISION - C1991078 (2)

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season grasses). In this regard, the reclaimed area exhibits 2 warm-season grasses (blue grama - 12.18% and alkali sacaton (Sporobo/us airoides) - 2.98%); 3 cool-season grasses (needle and thread - 18.78%, Indian ricegrass - 5.31%, and bottlebrush squirreltail - 3.89%); 1 forb (scarlet globemallow - 8.29%); and in addition 3 shrubs (four-wing saltbush - 13.73%, winterfat - 6.35%, and big sagebrush - 4.15%). In total, there are 9 taxa that fall within the 3% to 40% limitation for reclaimed area composition. By comparison, the native reference area data are presented which on average show modest failure against these standards. Therefore, should final bond release sampling indicate non- compliance with one of these criteria, there are arguments that indicate the standard has been set too high. A tabular illustration of this comparison is provided below. Number, o f Species with Between 3% & 40% Composition Adjacent Sagebrush Grassland Sagebrush Grassland Life Form Hamilton Reference Reference Reference Reference Reference Ref. Area Reveg Area Area - Area - Area - Area - Avg. Warm Season Grass 2 3 1 1 1 2 1.6 Cool Season Grass 3 3 1 - 2 - 1.2 Forbs 1 - - 1 - 1 0.4 Shrubs 3 - - - 2 1 0.6 Total 9 6 2 2 5 4 3.8 3.2 Revegetated Area Ground cover of the reclaimed area consisted of 38.6% live vegetation, 2.15% rock, 22.05% litter, and bare soil exposure of 37.2% (Table 2). Perennial cover across the unit averaged 30.15% with annual and biennial cover averaging 8.45%. Dominant taxa were needle and thread, four-wing saltbush, blue grama, cheatgrass (Bromus tectorum), scarlet globemallow, stork's bill (Erodium cicutarium), winterfat, and Indian ricegrass with 7.25%, 5.3%, 4.7%, 4.15%, 3.2%, 2.85%, 2.45%, and 2.05% average cover, respectively. 3.3 Reference Areas Ground cover of the adjacent area consisted of 19.5% live vegetation, 1.6% rock, 27.7% litter, and a significant level of bare soil exposure at 51.2% (Table 2). Perennial cover across the unit averaged 18.2% with annual and biennial cover exhibiting a modest 1.3%. Dominant taxa were Wyoming big sagebrush, blue grama, and needle and thread with 8.2%, 2.5%, and 2.2% average cover, respectively. CEDAR CREEK ASSOCIATES, Inc. Page 8 Hamilton Mine - Revegetation Evaluation - 2009