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discussed separately below. <br />Alkali Creek <br />Only a small portion of the permit area was within the Alkali Creek drainage basin. The <br />permit area within this drainage was limited to approximately three miles of light use road <br />used to monitor well SK 3.75. The applicant submitted very little information in regard to <br />alluvial valley floor designation of this drainage. Therefore, the Division conservatively <br />assumed that the unconsolidated streamlaid deposits in Alkali Creek comprise a significant <br />alluvial valley floor. There is no current groundwater monitoring, and this road will not be <br />used for access during the ensuing permit term. <br />Alkali Creek Findings <br />1) None of the light use road was located within the alluvial valley floor nor will it be <br />used during the ensuing term of the permit. Therefore, the Division fmds that the <br />proposed operation does not interrupt, discontinue, or preclude farming on the alluvial <br />valley floor. <br />2) There is no anticipated effect to surface water in the Alkali Creek drainage as a result <br />of remaining reclamation activities at the site. The Division fmds that the proposed <br />operation will not materially damage the quantity and quality of water in the surface <br />and underground water systems that supply the alluvial valley floor or portions of the <br />alluvial valley floor. <br />3) The proposed mining operation will not physically disturb the alluvial valley floor. As <br />discussed above, there will be no effects on the quantity and quality of water supplied <br />to the AVF Therefore, the Division fmds that the proposed mining operations will be <br />conducted to preserve, throughout the mining and reclamation process, the essential <br />hydrologic functions of the alluvial valley floor. <br />Colorado River <br />The applicant identified unconsolidated streamlaid deposits within and adjacent to the <br />proposed permit area which meet the minimum size requirement of 50 feet in width by 10 <br />acres in extent as set by the OSM alluvial valley floor guidelines. These unconsolidated <br />streamlaid deposits border the Colorado River. <br />Three distinct types of unconsolidated deposits were mapped which meet the geomorphic <br />criteria for alluvial valley floors. These deposits are quaternary terrace deposits, quaternary <br />transition zone between terrace and colluvial outwash, and quaternary colluvial outwash. <br />The unconsolidated sediments cover approximately 500 acres in the area of the surface <br />facilities between the Colorado River and the Grand Hogback. Of the 500 acres, 216 acres <br />are colluvial outwash; 136 acres are terrace deposits. Most of the area mapped as terrace <br />and transition zone deposits is presently used for irrigated agriculture. Only a small portion <br />of the area mapped as colluvial outwash is presently used for irrigated agriculture. The <br />Coal Ridge Mine <br />Permit Renewal No. 7 20 December 5, 2016 <br />