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• occur only during the three month period following the start of Spring <br />snowmelt. <br />Exhibit 2.7.3.B, "Overburden F-Seam," and Exhibit 2.S.l.U, "Location of <br />Springs,", from the permit application, were used to prepare the attached <br />new Exhibit 2.8.1.U.1, "Geologic Features used in the Projection of Mine <br />Inflows and Spring Depletions." This exhibit which also shows the major <br />fracture zones was used in conjunction with [he mine plan from the permit <br />application, Exhibit 3.4.4.B.1, "General 40 Year Mine Plan - F Seam," to <br />breakdown the inflows based on 5-year mining increments and the possible <br />effected watershed area. Exhibit 3.4.4.B.1 is being revised to reflect <br />changes in anticipated mining that will result in a reduction in the area <br />mined. As a result, all of the following impact predic[ions are overstated <br />and represent a worst case evaluation. However, in an effort to meet the <br />required deadline for responding to the questions, the unrevised Exhibit <br />3.4.4.B.1 was used. The results are summarized in new Table 2.8.S.J, <br />"Projected Mine Inflows and Stream Depletions Mt. Gunnison Mine #1," and <br />are separated into seasonal inflows (situation L) and perennial inflows <br />(situation 2). <br />(This answer is referred to in the answer to questions: V. A. 10; V. D. 1, <br />5, 8, 13, 29, and 30; 3/17/86 question #1.) <br />10. "In a worst case situation springs, seeps and ground water flow through <br />colluvium may be intercepted; for the Life of mine plan a chart should <br />be submitted to show when these seeps and springs may be intercepted <br />and how much flow will be removed from the Minnesota Creek Basin." <br />• A worst case spring impact analysis is provided in new Table 2.8.S.K, <br />"Worst Case Spring Impact Analysis". This new table includes all springs <br />issuing from the F-seam or from locations that are undermined where the <br />overburden cover is less than 300 feet. It also includes all springs in <br />the vicinity of major fracture zones that are undermined where overburden <br />cover is less than 500 feet. Furthermore, if [he surface drainage area <br />upgradient of a spring located in a major fracture zone is undermined where <br />the overburden cover is less than 500 feet, then the spring was assumed to <br />be potentially impacted regardless of its location with respect to the F- <br />seam. Likewise, if the surface drainage area upgradient of a spring not <br />located within a major fracture zone is undermined where the overburden <br />cover is less than 300 feet, then the spring was assumed to be potentially <br />impacted only if it is located within or above F-seam. <br />Springs located below the F-seam outside major fracture zones are not <br />expected to be effected by mining because the fire clay at the base of the <br />F-seam would severely restrict hydrologic communication with the units <br />below the F-seam. WCC-23 was the only spring issuing from below the F-seam <br />in the mine plan area that was located outside the major fracture zones. <br />The flow in spring WCC-23 is always less than 1 gpm and flows in response <br />to snowmelt and major precipitation events. Its source is evidently very <br />Localized. Nevertheless, since the spring is located within the disturbed <br />area associated with mine facilities it is included in the List of springs <br />that could be potentially impacted. <br />The only other spring below the F-seam that could be affected is WCC-24 <br />• located in the Dry Fork Valley about 280 feet below the F-seam. Since this <br />V-19 <br />