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2 <br />methane as the vacuum exhausters used to <br />accomplish degasification will not operate <br />given the increased resistance of smaller <br />diameter holes. The size anal weight of the <br />required equipment (95,000 to 136,000 pounds) <br />is far beyond the lift capabilities of even the <br />largest twin-rotor helicopters, which can only <br />lift upwards of 30,000 pounds at sea level. The <br />range of elevation for the collar sites of the <br />proposed methane drainage wells is 6,800 to <br />8,500 feet. Higher elevations have a significant <br />adverse impact to the lifting capacity of <br />helicopters. For safety reasons, in addition. to, <br />technical reasons regarding weight limits, this <br />alternative was not carried forward for detailed <br />analysis. <br />Comparison of Alternatives <br />different levels of effects or outputs can be <br />distinguished quantitatively or qualitatively <br />among alternatives. The analysis assumed that <br />since coal could not be mined economically <br />without the methane drainage, ventilation shaft <br />and escapeway, the Alternative 1 would result <br />in previously leased coal not being mined from <br />the area affected. As discussed earlier in this <br />chapter, the no action alternative would likely <br />cause underground coal mining operations in <br />the E seam to slow significantly or diminish <br />entirely over time, due to the economic <br />feasibility. <br />Agency Preferred Alternative <br />• <br />This section. provides a summary of the effects <br />of implementing each alternative considered in <br />detail (Table 2-2). Information in the table is <br />focused on activities and effects where <br />Alternative 2 -Proposed Action, including the <br />design criteria specified in Table 2-1 is the <br />Forest Service's preferred alternative. <br />• <br />• <br />48 Deer Creek Ventilation Shaft and E Seam Methane Drainage Wells FEIS <br />