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When COVCC mines under Steven's and East Roatcap Creek, water may <br />be encountered even if there is no subsidence. Faults and <br />fractures may be encountered underground that are in communication <br />with the stream and its associated alluvial/colluvial deposits. <br />Dewatering of these faults and fractures could diminish streamflow <br />and .the alluvium/colluvium when water is present. The limited <br />depletions are not predicted to be significant enough to cause a <br />major change in stream characteristics or impact the hydrologic <br />balance. The only concern with diminishment of Steven's Gulch or <br />East Roatcap Creek stream flow would be to water users within <br />those drainages. The operator has responded to this concern in <br />their water replacement plan. The Division's findings on this <br />issue are included in the Water Rights and Replacement discussion <br />in Section VII of this document. <br />Based on data from other mines in the valley, the Division would <br />anticipate stream-related inflows to be only a few hundred gallons <br />per minute at worst case during certain times of the year when the <br />streams are flowing. Following a detailed investigation and <br />analysis, the operator has predicted that worst-case inflows from <br />East Roatcap Creek would be 5.2 gpm and inflows from Steven's <br />Gulch would be 5.7 gpm. These would increase to 33.5 gpm for the <br />life of mine. Inflows below East Roatcap Creek have averaged less <br />than 1 gpm. A mitigation plan has been approved that will replace <br />any water lost by mining. <br />The hydrologic consequences of the mine are expected to be <br />minimal. The applicant reports that no degradation of water <br />quality in surface streams is expected. Any effluent will be <br />treated as necessary to meet quality standards prior to <br />discharge. Although mine inflows are currently small, if inflows <br />are encountered the application contains a plan for a collection <br />and treatment prior to discharge. <br />Conclusion - <br />An assessment of the probable hydrologic consequences of the <br />mining operation and an assessment of the probable cumulative <br />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), <br />the Division finds that the Orchard Valley mining operation has <br />been designated to minimize hydrologic impacts within the permit <br />boundary, and to prevent material damage to the hydrologic balance <br />outside the permit area. <br />IV. Topsoil <br />Since no topsoil was salvaged, an analysis of the original Orchard <br />Valley Mine bench material (Volume 9 - Soils Test Appendix) was <br />conducted. The analysis indicates that the material is suitable as a <br />plant growth medium. This is also true for the storage and loadout <br />areas. Vegetative growth on fill outslopes has occurred. At final <br />reclamation in these areas, the operator has committed to ripping and <br />testing this material for fertility. Fertilizers and amendments will <br />be added as necessary. The area will then be seeded and mulched. <br />-31- <br />