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Surface Water Impacts <br />The disturbed area is a regraded and vegetated portal face-up slope and bench. Much of the <br />runoff from the portal face-up slope and bench is routed along a ditch next to the public road that <br />crosses the disturbed area. Water in the ditch would make its way to the ditch next to U.S. <br />Highway 160 where drainage passes through a culvert and goes on to Lightner Creek <br />approximately one mile downstream from the Arness-McGriffin Site. <br />Surface runoff from the disturbed area can be expected to be alkaline and free of contaminants as <br />there are no leachate-forming materials on the land surface. The quality of this runoff should be <br />closely similar to runoff from surrounding undisturbed lands, and therefore, does not have the <br />potential to degrade surface waters downstream from the Arness-McGriffin Site. <br />Risks to Public Health, Safety and Environment <br />A potential risk to public health, safety, and environment at the Arness-McGriffin Site would be <br />the steep slope next to the access road. The Division has installed a post-and-steel-cable guard <br />rail to mitigate this hazard. This road provides public access to the State of Colorado's Perins <br />Peak State Wildlife Area. The Colorado Division of Wildlife, and others, are responsible for <br />maintenance of this road. <br />The Arness-McGriffin Site is not located near or above any urbanized areas, communities, occupied <br />dwellings, schools, or other public or commercial buildings or facilities. <br />Impacts to Alluvial Valley Floors (AVFs) <br />There are no alluvial valley floors within the area of influence of the Arness-McGriffin Site. The <br />Coal Gulch drainage, immediately downslope from the Arness-McGriffin Site, does not meet the <br />regulatory definition of an alluvial valley floor as it lacks sufficient water for flood irrigation and <br />sufficient alluvium for subirrigation. <br />Findings on Protection of Hydrologic Balance <br />The only hydrologic structure remaining on the site is the ditch next to the public road that crosses <br />the site. No water pollution is occurring. The observed hydrologic impacts are consistent with <br />those predicted in the Division's Animas River Cumulative Hydrologic Impact Assessment. Based <br />on the foregoing observations, the Division finds that the Arness-McGriffin Site has minimized <br />disturbance of the hydrologic balance in the mine plan and adjacent areas, and prevented material <br />damage outside the permit area. The Division also finds that the Arness-McGriffin Site has not <br />caused hydrologic changes that adversely affect a postmining land use of wildlife habitat in the <br />permit area. <br />V. SUMMARY <br />The Arness-McGriffin Site is an unpermitted disturbance that was reclaimed with forfeited bond <br />8