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and the alluvium /colluvium when water is present. The limited depletions are not predicted to be <br />significant enough to cause a major change in stream characteristics or impact the hydrologic <br />balance. The only concern with diminishment of Steven's Gulch or East Roatcap Creek stream <br />flow would be to water users within those drainages. The operator has responded to this concern <br />in their water replacement plan. The Division's findings on this issue are included in the Water <br />Rights and Replacement discussion in Section VII of this document. <br />Based on data from other mines in the valley, the Division would anticipate stream related <br />inflows to be only a few hundred gallons per minute at worst case during certain times of the <br />year when the streams are flowing. Following a detailed investigation and analysis, the applicant <br />has predicted that worst case inflows from East Roatcap Creek would be 5.2 gpm and inflows <br />from Steven's Gulch would be 5.7 gpm. These would increase to 33.5 gpm for the life of mine. <br />Inflows below East Roatcap Creek have averaged less than 1 gpm. A mitigation plan has been <br />approved that will replace any water lost by mining. <br />The hydrologic consequences of the mine are expected to be minimal. The applicant reports that <br />no degradation of water quality in surface streams is expected. Any effluent will be treated as <br />necessary to meet quality standards prior to discharge. <br />Cnnrincinn <br />An assessment of the probable hydrologic consequences of the mining operation and an <br />assessment of the probable cumulative impact of all anticipated mining in the general area on the <br />hydrologic balance has been made. Pursuant to Rule 2.07.6(2)(c), the Division finds that the <br />Bowie No. 1 mining operation has been designated to minimize hydrologic impacts within the <br />permit boundary, and to prevent material damage to the hydrologic balance outside the permit <br />area. <br />IV. Topsoil - Rule 4.06 <br />Since no topsoil was salvaged at the East Mine, an analysis of the original Orchard Valley Mine <br />(East Mine) bench material (Volume 9 - Soils Test Appendix) was conducted. The analysis <br />indicates that the material is suitable as a plant growth medium. This is also true for the storage <br />and loadout areas. Vegetative growth on fill outslopes has occurred. At final reclamation in <br />these areas, the operator committed to ripping and testing this material for fertility. Fertilizers <br />and amendments were to be added as necessary prior to the area being seeded and mulched. <br />Because of the limited available area at the Bowie No. 1 West Mine, topsoil was stored in two <br />areas - outslopes of the portal bench and a topsoil stockpile north of the portal bench. Topsoil on <br />the bench outslopes was spread to a depth of approximately four feet, seeded and stabilized with <br />an erosion control blanket. The topsoil stockpile was protected from erosion by seeding and <br />mulching. Details are located in the approved permit application, Volume IA, Section 2.05.4. <br />Topsoil from the bench outslopes and topsoil stockpile has since been spread over the backfilled <br />and graded area. <br />During initial development of the West Ridge waste disposal pile, approximately 24 inches of <br />topsoil was salvaged. As waste pile expansion occurred, soil material was analyzed to determine <br />optimal salvage depths. Approximately eight to nine inches of topsoil was salvaged from this <br />area. Topsoil was stockpiled and protected from erosion by seeding and mulching. Depth of <br />total cover and depth of topsoil were determined during an inspection held on July 15, 2003. <br />Page 26 of 42 <br />