2013-01-29_PERMIT FILE - C1981022A (3)

Home Browse Search

Ssriar - ?.05.6 Due to quality and yield considerations, surface water and associated alluvial/colluvial units are the • prirnaty water supply sources in the area. Of the four identified ground water units, the only unit that could potentially provide adequate quantities of water of suitable quality to support beneficial use is the alluvial/colluvial aquifer system In the mine permit and adjacent areas, beneficial surface water uses are limited to the Nonh Fork of the Gunnison River, Thompson Creek, and Hubbard Geek Existing water rights documentation, indicates a total of fifteen ground water rights and twenty-one surface water rights in the mine and adjacent areas. Of the identified ground water rights, the majority are associated with alluvial/colluvial deposits along the Noah Fork or in the lower portions of some of the tributary drainages or with shallow ground water in the Hubbaid Creek drainage to the west. Ground water uses in the area are limited to individual domestic water supply, small stock watering and imgation, small municipal water supply, and mine use. Of the identified surface water rights; five are associated with mine ponds used for drainage and sediment control and water for duct control; one is associated with the Blue Ribbon Reservoir No.l; one fs associated with an individual domestic water supply, and the rem~~n~~g rights are associated with irrigation ditches, canak, and pipelines. Because of the ragged terrain in the mine vicinity, most imgation use occurs at least five miles downstream, east of the Town of Paonia, where the North Fork Valley opens out into a broad alluvial plain. With limited flows and significant seasonal fluctuations in the smaller drainages, the North Fork, Thompson Geek, and Hubbard Geek are the only drainages in the mine vicinity which are subject to surface withdrawak. Hydrologic Protection Plans - In order to minimi~a potential mining-related impacts to existing hydrologic systems in the pemrit and adjacent areas, OMI has incorporated specific monitoring, operational, and mitigation measures into the mining and reclamation plans for the Somerset, Sanborn Geek, and Elk Geek Mutes. These measures are based on historic and baseline monitoring information for the site, the experience of other nearby mining operations in controlling hydrologic • impacts, applicable regulatory requirements, and the results of ongoing monitoring programs. Ffutoric and baseline monitoring data have been rued to characterize current hydrologic conditions including seasonal charatteristics as described in Section 2.04.7, Hydrologic Description. During the operation of the mine, monitoring will be performed to determine if any mining-related impacts to the hydrologic balance have occurred and remedial attions taken, if necessary. Measttres that tray be taken to remediate any miming-related impatts to the hydrologic balance are addressed in the hydrologic restoration plans. Operational plans for the active, Sanborn Creek and Elk Geek Mines include standard hydrologic controk and mitigation meastuES that are designed to prevent significant changes in the quantity and quality of surface and ground water resources, preserve existing hydrologic fimaionc, comply with regulatory requirements, and limit adverse impacts to surface water or ground water users. These measures include: • Limiting surface disturbance areas • Proper design, construction, and grading of facilities areas and roads • Construction of drainage and sediment control structures to divert undisturbed nmoff azotmd disturbance areas, collect and route disturbed area rtmoff to sedimentation ponds to allow settlement of suspended solids, and provide any treatment which may be necessary to meet applicable discharge effluent limitations • Interim revegetation of disturbed cut and fill slopes not used for operations and • revegetauon of topsbu stocicpues, poha outstopes aha-other unus6a areas. • L h;l;>ation of localized erosion control measures, as appropriate, in any areas having high erosion potential PR04 2.05-77 Revised August 2000