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Portions of the Good Spring Creek valley within and adjacent to the permit area, downstream of <br />existing and current operations, are currently flood irrigated. Ranchers grow pasture grasses for <br />hay and livestock forage production in the flood irrigated fields. A few wells and springs located <br />along Good Spring Creek are being used for stock watering. <br />Lower Elkhorn Creek will not be affected directly or indirectly by mining at Colowyo Mine. <br />Stream Valley Segments Determined not to be Alluvial Valley Floors <br />Taylor Creek was investigated in the early 1980s in association with initial permitting of the Mine, <br />and was determined not to be an alluvial valley floor. <br />Lower Taylor Creek, a tributary to Wilson Creek, contains small areas with alluvial deposits, but <br />does not contain enough water to provide for sub -irrigation of croplands. Taylor Creek, which <br />will be mined in its upper reaches, is therefore not considered an alluvial valley floor. <br />The West Fork of Good Spring Creek was investigated in association with PR -02, and was <br />determined not to be an alluvial valley floor due to the restricted width of the alluvial deposit along <br />most of the reach, and the absence of sub -irrigated or flood irrigated agricultural activity (current <br />or historic). <br />Wilson Creek and Jubb Creek were investigated in association with TR -109, and were determined <br />not to be alluvial valley floors due to a mass -wasting event that occurred in 1983-1984. This event <br />downcut the valley fill throughout the area lowering the groundwater table and drying former <br />wetlands. After this mass wasting event occurred, native upland plant species, which would not <br />normally be found in regional AVFs, were then able to establish itself in the area. <br />Other Stream Valleys in the General Area <br />Various other stream valleys with unconsolidated alluvial deposits in the mine vicinity may meet <br />alluvial valley floor criteria, but have not been evaluated as a part of this review because they are <br />located outside the proposed permit boundary or there is no proposed mine disturbance within their <br />watersheds. These valleys the East Fork of Good Spring Creek, located upstream of any mining, <br />and James Creek, located upstream of any mining. <br />B. Primary Impacts <br />None of the two designated alluvial valley floors are within the area to be mined; therefore, mining <br />operations will not cause direct disturbance to any alluvial valley floors. Any mining impact that <br />might occur will be indirect in nature. <br />C. Secondary Impacts <br />Revised Proposed Decision and Findings of Compliance August 2018 <br />Permit Renewal No. 7 P a g e 155 <br />