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Based on data from other mines in the valley, the Division-would anticipate stream-related inflows to be only a few hundred gallons per minute at worst case during certain times of the year when the streams are flowing. Following a detailed investigation and analysis, the operator has predicted that worst-case inflows from East Roatcap Creek would be 5.2 gpm and inflows from Steven's Gulch would be 5.7 gpm. These would increase to 33.5 gpm for the life of mine. Inflows below East Roatcap Creek have averaged less than 1 gpm. A mitigation plan has been approved that will replace any water lost by mining. The hydrologic consequences of the mine are expected to be minimal. The applicant reports that no degradation of water quality in surface streams is expected. Any. effluent will be treated as necessary to meet quality standards prior to discharge. Although mine inflows are currently small, if inflows are encountered the application contains a plan for a collection and treatment prior to discharge. Conclusion - An assessment of the probable hydrologic consequences of the mining operation and an assessment of the probable cumulative impact of all anticipated mining in the general area on the hydrologic balance has been made. Pursuant to Rule 2.07.6(2)(c), the Division finds that the Orchard Valley mining operation has been designated to minimize hydrologic impacts within the permit boundary, and to prevent material damage to the hydrologic balance outside the permit area. IV. Topsoil Since no topsoil was salvaged, an analysis of the original Orchard Valley Mine bench material (Volume 9 -.Soils Test Appendix) was conducted. The analysis indicates that the material is suitable as a plant growth medium. This is also true for the storage and loadout areas. Vegetative growth on fill outslopes has occurred. At final reclamation in these areas, the operator has committed to ripping and testing this material for fertility. Fertilizers and amendments will be added as necessary. the area will then be seeded and mulched. Because of the limited available area at the Orchard Valley West Mine, topsoil is stored in two areas - outslopes of the portal bench and a topsoil stockpile north of the portal bench. Topsoil on the bench outslopes was spread to a depth of approximately four feet, seeded and stabilized with an erosion control blanket. The topsoil stockpile is protected from erosion by seeding and mulching. Details are located in the approved permit application, Volume lA, Section 2.05.4. During initial development of the West Ridge waste disposal pile, approximately 24 inches of topsoil was salvaged. As waste pile expansion occurs, soil material will be analyzed to determine optimal salvage depths. Currently, eight to nine inches of topsoil is -31-