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Se7im - 1.04.7
<br />Analyse values indicate a neutral to slightly alkaline pH and elevated EC, TDS, hardness, and
<br />dissolved iron and manganese, as S,imman~rd by Tables 2.04.7-T3B, B Coal Seam Water Quality
<br />Summary and 2.04.7-T3C, D Coal Seam Water Quality Summary. Characteristic of deeper perched
<br />ground water, the stored mine water e somewhat isolated from and less subject to seasonal
<br />fluctuation in water level and water quality Generally, the quality of stored mine water is consistent
<br />with deep perched ground water, being fair to good with somewhat elevated TDS, TSS, and dissolved
<br />metals. For active mine areas, the only treatment typically required for mine water discharge to meet
<br />applicable effluent standanis e temporaryretention to allow settling of suspended solids.
<br />Ground Water Rights and Use -Due to quality and yield considerations, surface water and
<br />associated alluvial/colluvial units are the ptirnary water supply sources in the area. Of the three
<br />identified ground water units previously discussed, the only unit which provides adequate quantities of
<br />water of suitable qualityto support beneficial use is the alluviaVcolluvial aquifer syscem.
<br />Existing water rights documentation, as updated by the Colorado Division of Water Resources in
<br />August 1997 and s,~mmari~rd in Table 2.04.7-T4~Water Rights Surturtaty -Mine and Adjacent Areas,
<br />indicates a total of fifteen ground water rights in the mine and adjacent azeas. Of the identified
<br />ground water rights, as shown on the Surface Water Hydrology Map, (Map 2.04-M6), all are
<br />associated with the North Fork or tributary alluvial/colluvial deposits except Hotchkiss Spring No. 1,
<br />TonyBeaz Yuma Spring, Mt. Gunnison Mine, and several water rights associated with shallow ground
<br />water in the Hubbard Cmek drainage to the west (Blue Ribbon Well, J&M Spring, and Pipeline Nos. 1
<br />and 2).
<br />As indicated by Table 2.04.7-T4, allocations for the identified ground water rights are relatively small,
<br />ranging from 0.004 to 1.002 cfs. Ground water use in the area is limited [o individual domestic water
<br />supply (Kanzler Well, Norris Well No. 1, Tony Bear Yuma Spring, New Majnik House Well, Sell No.
<br />1 Well); small stock watering and imgation (Hotchkiss Spring No. 1, J&M Spring and Pipeline Nos. 1
<br />and 2); small municipal water supply (Somerset Water Supply System, Somerset P/A); and mine use
<br />(Somerset Mine Well, Bear Well No. 1, Hawk's Nest Well, Mount Gunnison Mme, Blue Ribbon
<br />Well).
<br />Surface Water Information
<br />In the mine permit and adjacent areas, beneficial use of surface water is generally limited to ditch
<br />withdrawak from the larger surface drainages for small-scale local or downstream irrigation use.
<br />Because of the rugged terrain in the mine vicinity, most irrigation use occurs at least five miles
<br />downstream, neaz the Town of Paonia, where the North Fork Valley opens out into a broad alluvial
<br />plain. Because of limited flows and significant seasonal fluctuations in the smaller drainages, the
<br />North Fork, Thompson Creek, and Hubbard Creek are the only drainages in the mine vicinity which
<br />are subject to surface withdrawak. Given these considerations, the significance of surface water
<br />resources relative to ongoing and proposed mining operations involves potential mining-related
<br />impacts on surface runoff characteristics, perennial drainages, and disturbed area or mine water
<br />discharge to surface drainages. The following sectioru characterize surface water occurrence,
<br />environment and conditions as a basis for evaluation of these potential impacts.
<br />Mine Area Watersheds, Surface Water Occurrence, and Relationship to Mining Disturfiance -
<br />The regional surface watershed area, which includes the mine pemtit and adjacent areas, is the
<br />watershed of the North Fork of the Gunnison River as shown by Figure 2.04.7-F8, Surface
<br />Watershed Area. The regional watershed is defined bythe crest of Grand Mesa to the north, the crest
<br />of the Elk Mountains to the east and south, and the Colorado River Valley to the west. Within the
<br />regional surface watershed area, the terrain is generallymountainous with Englemann spruce/blue
<br />r~
<br />u
<br />PR04 2.04-50 Revised August 2000
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