2009-04-01_REPORT - C1982057 (6)

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• precipitation total for the 12 months preceding sampling just slightly above average (Figure 7b). 2008 was also a well below average year as regards temperature - in fact it was the coolest year in the 22-year record (started in 1986) (Figure 10). These cooler temperatures likely extended snowpack duration and soil moisture somewhat further into the dry summer months providing vegetation with much needed moisture, as the rest of the summer would be characterized by well below average precipitation (Figure 6b). In the context of the six or four-months preceding sampling (Figures 8b and 9b, respectively) it is clear that the middle part of 2008 encountered below average precipitation which essentially acted to stunt vegetation growth for the rest of the season. At the time of sampling, it was clear that vigorous vegetation growth in both native and reclaimed areas had encountered moisture deficiency with associated minor wilting and predominant dull green luster. Biotic Factors Affecting Vegetation Grasshoppers plagued the reclaimed areas of several of the Seneca mines in 2008 and may have negatively affected overall cover and production values. The predominant plant species that appears to have been targeted and denuded by grasshoppers was alfalfa. These effects were most notable at the Seneca IN mine. • Cover Observed cover values and derivation of the 2008 herbaceous cover standard are compiled/documented in the table below: Seneca IIW 2008 Vegetation Type Mean Cover* % of Affected Aread Sagebrush/Snowberry a 36.2 31.3 Mountain Brush a 34.7 34.5 Aspen Woodland a 84.7 11.0 Steep Mountain Brush 18.5 12.8 Alkali Sage./West. Whtgrs. 31.0 10.4 2004 Reclamation Area 28.5 NA 2006 Reclamation Area 9.0 NA 2007 Reclamation Area 10.8 NA "All-hit" ref. area cover standard for 2008 (Adj. Means weighted by % of Affected Area) = 38.2% 90 percent of 2008 ref. area cover standard = 0.9 x 36.2 = 34.4 • 12