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The Division has made the determination that portions of four drainages with segments in or <br />adjacent to the Colowyo permit azea (as expanded by PR-2) aze considered alluvial valley floors: <br />Good Spring Creek, Wilson Creek, Lower Elkhorn Creek, and Jubb Creek. These stream valleys <br />aze shown on Map 11 A of the Permit. Neither Lower Elkhorn Creek nor Jubb Creek will be <br />affected directly or indirectly by mining at Colowyo. The designation of Jubb Creek as an AVF <br />is based solely on the presence of unconsolidated streamlaid deposits indicated on Map 11 A. <br />Insufficient information regazding current, potential, or historic flood irrigation, or presence of <br />subirrigated agricultural activity was provide for Jubb Creek, to allow for detailed assessment <br />and possible negative determination. <br />Flood irrigation may have occurred in the past along portions of Wilson Creek within the permit <br />azea as expanded by PR-2. Small cropland parcels within a mile or so to the north (downstream) <br />of the permit boundary in the vicinity of Gossazd Loadout were historically irrigated cropland <br />(grass hay). These parcels aze currently in dryland wheat, no longer irrigated. There is current <br />flood imgation (grass hay) along a segment of the stream immediately to the south (upstream) of <br />the expanded permit boundary. Portions of the Good Spring Creek valley within and adjacent to <br />the permit azea, downstream of existing and proposed future operations are currently flood <br />irrigated. Ranchers grow pasture grasses for hay and livestock forage production in the flood <br />irrigated fields. A few wells and springs located along Goodspring Creek are being used for stock <br />watering. Good Spring ,Lower Elkhorn Creeks, and portions of Wilson Creek contain <br />unconsolidated stream-laid materials and have sufficient water for sub-irrigation to benefit <br />agriculture. Due to the presence of flood irrigation along portions of these drainages (see Map <br />17), as well as sufficient water for sub-irrigation and potential for flood irrigation in other <br />locations, portions of these stream valleys within and adjacent to the proposed permit azea have <br />been found by the Division to be alluvial valley floors. Insufficient information has been <br />provided regarding water availability for flood irrigation or subirrigation agricultural activities on <br />Jubb Creek, and as a result, the segments of Jubb Creek and its tributaries mapped as Qa on Map <br />11A have been determined at this time to meet the alluvial valley floor criteria (this <br />determination may be altered or refined in the future based on submittal of additional <br />information). Although a short reach of Jubb Creek is within a corner of the expanded permit <br />boundary, there aze no proposed mine disturbances within the Jubb Creek watershed. <br />Based on presently available information, including information provided in the permit <br />application and field reconnaissance by Division staff, the following stream valley segments have <br />been determined to be alluvial valley floors: <br />Good Spring Creek valley deposits mapped as Qa on Map 11A, extending from the West <br />Fork Good Spring Creek confluence downstream for the entire length of the valley. <br />Upper segment of Wilson Creek valley deposits mapped as Qa on Map 11A, from the <br />confluence of East and West Forks of Wilson Creek, downstream to the approximate <br />center of Section 7, T3N, R93 W. (Area extending downstream of this point for several <br />miles, delineated on Map 11A as "Affected by 1985 Erosion and Mass Wasting Event", <br />has been determined by the Division not to be an alluvial valley floor). <br />Proposed Decision and Findings of Compliance 4 May 2007 <br />Permit Revision 02 Page 62 <br />