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294M. In subsequent years, the point of compliance will be monitoring well 22- <br />3M. <br />F. Stream Buffer Zones <br />1. The Division approved underground mining activities within 100 feet of a <br />perennial stream with a biological. community. This decision was based on a <br />finding that the original stream channel will not be affected, water quality <br />and quantity will not be adversely affected as a result of the disturbance, and <br />appropriate riparian vegetation will be reestablished upon final reclamation. <br />The buffer zone variance is granted for the raw water lagoon and dike along <br />the White River, at the mouth of Scullion Gulch. A riparian revegetation <br />plan is provided in Section V. 1.4h of Volume IV of the permit application <br />(4.05.18(1)). <br />G. Probable Hydrologic Consequences <br />The probable hydrologic consequences of mining within the Deserado Permit <br />Area are addressed within Section II.C.5 of Volume I of the permit application. <br />The permittee's statement of hydrologic effects has been reviewed by the Division <br />for compliance with Rule 4.05.1 and 2.05.6(3). <br />Surface Water Impacts <br />Impacts to the hydrologic balance will occur as a result of the mine. Short- <br />term impacts which will occur as a result of surface facilities appurtenant to <br />the underground mine include reduction of water yield from the mine area to <br />the White River, increased sediment loads from disturbed areas, and water <br />quality degradation from the refuse disposal area and mine water discharge. <br />Long-term impacts will center on the effects of subsidence under Scullion <br />Gulch and Red Wash. See the subsidence section of this document for <br />further discussion of subsidence impacts. <br />Small short-term surface water losses will occur as a result of two factors: <br />retention of water in ponds and removal of water from the White River <br />lagoon. Runoff from disturbed areas will be routed through sedimentation <br />ponds, thereby reducing the amount of flow to the White River. Evaporation <br />losses will occur, as the ponds will not discharge runoff until the point of <br />available storage volume is achieved. Clay subsoils, which comprise the <br />bottom of the sedimentation ponds, will allow very little impounded water to <br />re-enter the ground water system. Losses from the D-Portal pond will be <br />insignificant when compared to total runoff from the Scullion Gulch <br />watershed. Scullion Gulch has a contributing drainage area of 7,552 acres at <br />its confluence with the White River, with the D-Portal pond designed to store <br />runoff from only 44 of the acres. The refuse disposal area ponds are <br />designed to receive runoff from approximately 98 acres, which is a small <br />portion of the 2,950 acres drained by the Red Wash tributary through the <br />Deserado Mine 32 June 18, 2009