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RULE 2 PERMITS <br />.r .,..cr.s^•,s :r NZ'^.., er,'cs, , « .. _ ,a .. _ 'aa,,."s: _':� ..'K:�" >_ :s}.ri�i: 1: -^.: -_. _,..'r%' _ .' o:' a : v .e ,"':' „ ,:'�'S„�'A.k <br />in the area to be mined; however, some of the floodplains of Good Spring Creek, West Fork Good Spring <br />Creek, Wilson Creek, lower Taylor Creek, and lower Jubb Creek may conform to the geomorphic criteria <br />of alluvial valley floor (AVF) surface landforms because they are underlain by unconsolidated material of <br />Quaternary Age (Map 11B). None of these floodplains are located in the area to be mined as shown on <br />Map 23A. <br />The Gossard Loadout is located in an area between Wilson Creek and Taylor Creek near the junction of <br />these two drainages; however, no major subsurface disturbance has occurred in this area that might <br />adversely affect the possible subsurface hydrologic system with regards to potential alluvial valley floors. <br />The actual area to be mined is located well above the flood plain of Wilson, Taylor, and Good Spring <br />Creeks, both topographically and hydrologically. As discussed in Section 2.04.7, the existence of <br />groundwater in the mining area is limited to perched systems that primarily discharge small amounts of <br />water in the canyon walls near the mine on a seasonal basis and in some of the unconsolidated alluvium. <br />Very little water is found in the current active mine; and, based on existing geological and hydrological <br />evidence, the areas to be mined provide no or only minor amounts of recharge to local surface water <br />features. Therefore, the flood plains of Wilson Creek, Good Spring Creek, lower Taylor Creek, and their <br />tributaries will not be directly impacted except at road crossings (discussed elsewhere in the application) <br />and should not be adversely affected by mining operations. <br />Geomorphic Characteristics <br />The investigation was initiated by mapping unconsolidated deposits in the general area, using published <br />and unpublished geologic maps and ground reconnaissance. These deposits, their associated stream <br />channels and the general topography of the floodplain areas are shown on Map 10. The watersheds of <br />Good Spring Creek, Wilson Creek, and Taylor Creek are also delineated on Map 10. From field <br />reconnaissance, it was determined that many of the mapped floodplains in the general area are extremely <br />narrow, have been severely down -cut (Wilson and Jubb Creeks), and/or contain too much topographic <br />relief in the form of slopes to be considered capable of being irrigated. <br />Agricultural Activities <br />Section 2.04.3 contains a description and map of agricultural activities in the permit and adjacent area. <br />The Land Use Map (Map 17) shows that the historic pre -mining land use of the area has been generally <br />undeveloped rangeland. The description under Section 2.04.3 documents crops in the permit area. <br />Historically, there has not been a developed water supply for agricultural activities to expand upon; <br />however, some limited irrigation is conducted in the floodplains of Good Spring Creek and Wilson Creek. <br />Flood Irrigation — The areas that are currently or were historically flood irrigated are shown on Map 17, <br />Land Use. Irrigation diversion points, irrigation canals, and topography are shown on Map 10. A small <br />area of Wilson Creek above the mine permit boundary is irrigated, and some areas near the Gossard <br />Loadout have historically been irrigated. No irrigation has occurred in West Fork Good Spring Creek. <br />Subirrigation — The channel fill of the floodplains in the canyon areas is generally comprised of <br />unconsolidated deposits in a clay matrix. The clay soil texture will minimize the transmission of water to <br />or from the overlying stream and root zone. Due to the narrow area in the floodplains, the overall slope of <br />the drainage and expected clay soil, the likelihood of a developed subirrigation in the canyon areas is <br />questionable. <br />The West Fork Good Spring Creek does not meet the criteria of an AVF based on field reconnaissance. It <br />has areas with flat topography and clayey soil where surface water occasionally accumulates after <br />precipitation. This allows the valley bottom to support lush vegetation without subirrigation. Monitoring <br />South Taylor/Lower Wilson — Rule 2, Page 88 Revision Date: 4/7/17 <br />Revision No.: RN -07 <br />