2011-09-29_PERMIT FILE - M2009056

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Mitigation/Residual Effects: Same as the proposed action WILDERNESS, AREAS OF CRITICAL ENVIRONMENTAL CONCERN, WILD AND SCENIC RIVERS Affected Environment: This area does not include any public lands with these special designations or areas with wilderness characteristics or qualities. HYDROLOGY/WATER RIGHTS Affected Environment: The proposed mine would be located in the Middle Fork of the South Platte River watershed approximately 400 feet southwest and 80 feet above the river itself. The site is in a dry, upland location that receives approximately 17 inches of precipitation annually. There is no surface water other then the river nearby. Using data from surrounding wells and the local geology, it appears that the major source of groundwater in the area is located in an alluvial aquifer tributary to the Middle Fork of the South Platte at approximately 50 to 75 feet below ground level. Water yields from this aquifer appear to be quite high with yields of 15 gallons per minute common. Most all of the surrounding wells are for domestic use and greater yields may be possible. Due to the close proximity to the river and the typical transmissivity of alluvial aquifers, groundwater recharge is expected to be fairly quick. Water from the proposed well would be appropriated through the state water rights process and would be subject to state water rights laws. Environmental Effects Proposed Action Direct and Indirect Impacts: The Proposed Action would allow a mine covering slightly less than five acres to be located on the public lands. This mine would consist of an open pit on approximately 1.5 acres with equipment and materials covering most of the rest. All water used in the operations would be recycled and not allowed to flow on the ground. No groundwater would be exposed by the operations and it is anticipated that mining would not get closer than ten feet from the water table. The site would be constructed with a berm around it that would control surface flow off /within the site; therefore surface hydrology would be minimally impacted. In addition to the mine, the proposal would eventually drill a well to supply water for the operations. It is unknown what volume of water would be required; however, considering that water would be trucked in until the well is complete and the system recycles all water, it is not anticipated that large amounts of water would be needed from the well. The well would be constructed with a state permit and would be required to obtain water rights for the water used. This would protect existing users as the well would most likely have a junior water right. It is assumed that the well would be drilled into the near surface, tributary alluvial aquifer. There is the possibility that it could be drilled deeper into a non - tributary aquifer, either way it would be required to go through the Colorado water courts. Cumulative Impacts: The South Platte Basin is a fully or over appropriated basin meaning that there is no new water available. The addition of the Proposed Action would further commit more 50