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Climatic Conditions <br />Year 2000/2001 climatic conditions at the Colowyo Mine were characterized by a <br />relatively dry fall, winter, spring and early summer prior to sampling (Figures 1 and 2). <br />Evaluation of precipitation over the 12-, 6-, and 4- month periods prior to sampling in late <br />July and early August (Figures 3, 4, and 5) shows that 2001 was as dry or drier than any <br />of the four years of record. With regard to the relative warmth of the year, it would <br />appear that year 2000 was somewhat warmer than average (Figure 6). Although no <br />long-term average temperature record exists at Colowyo, the total degree-days from~~ <br />January through July 2001 at the nearest NOAA sites with appropriate record (Hayden <br />to the northeast and Rangely to the southwest) were 5 to 10 percent above long-term <br />average. This suggests that evaporative losses from soil and transpirative stress in <br />plants would have been relatively high. It would appear that wind during 2000/2001 <br />(Figure 7) was about average. Thus, taken all together, relatively low precipitation <br />combined with higher than average temperatures are likely in general to have stressed <br />and limited plant growth during the 2001 growing season to a greater degree than <br />average conditions. <br />• Cover <br />Herbaceous cover in the 1997 areas ranged from 45.1 percent in the Section 16 <br />reclamation to 43.2 percent in the West Pit and to 29.0 percent in the East Pit. No <br />reduction for noxious weeds and/or annual/biennial species in excess of 10 percent <br />relative cover is needed to adjust these numbers to what is "allowable" under DMG <br />guideline. To the extent that original data from the reference areas (collected in 1980 <br />and 1981) are still valid, the performance standard far cover would be 32.9 percent (90 <br />percent of the area weighted herbaceous cover of the reference areas). Hence, the <br />Section 16 and West Pit reclamation would easily pass, and the East Pit cover for the <br />1997 area would barely fail (the upper end of the confidence range at 90 percent would <br />be 31.8 percent). The lack of certainty about the current values for cover in the <br />reference areas leaves some doubt about the reality of such a failure to meet the cover <br />standard. Since 2001 was a relatively dry year, it may well be that the cover levels in the <br />reference areas are slightly lower than was assumed here, with the consequence that <br />East Pit 1997 Reclamation cover levels would pass the standard. <br /> <br />4 <br />