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Ground Water Impacts <br />The underground workings of the Blue Flame Mine probably are above the current ground water <br />saturated zone (Figure 3). The elevation of the top of the saturated zone is considered to be <br />stabilized at its approximate current position. Only a significant long-term change in regional <br />climate or significant nearby well pumping would significantly raise or lower this elevation. <br />Over time, meteoric water probably infiltrates from the land surface down into the abandoned <br />underground workings of the Blue Flame Mine. As this water slowly accumulates in the workings, <br />it would seep into the bedrock walls of the workings, and migrate downgradient to the saturated <br />zone. The expected migration direction would be generally southward from the workings. Any <br />minerals which this migrating water picks up in the mine workings would be carried to the saturated <br />zone. If the mineral content of this migrating water is high, then it could pollute the ground water in <br />the saturated zone. The infiltration and migration process would take many decades owing to the <br />slow infiltration rate and the low hydraulic conductivity of the Cliff House Sandstone and Menefee <br />Formation. It is improbable that any water from the Blue Flame workings has reached the saturated <br />zone, yet. <br />Also, it is improbable that the Blue Flame workings have discharged water to the land surface in the <br />portal area because it would take many decades to fill the workings high enough to exert significant <br />pressure in the portal area. No seepage or discharge from the portal area has been found during the <br />Division's regular inspections. The improbability of current degradation to the saturated zone, and <br />the absence of discharges from the portal, indicate the Blue Flame Mine is not causing ground water <br />pollution, and the operation is in compliance with the Basic Standards for Ground Water (Colorado <br />Water Quality Control Regulation 41.S.C.6). <br />Surface Water Impacts <br />The only surface water feature that would receive surface runoff from the Blue Flame surface <br />disturbance is Hay Gulch. The Gulch does not have a stream channel. An irrigation ditch flows <br />through the bottom of the Gulch. GCC Energy monitors the quality of Hay Gulch alluvial water in <br />alluvial wells, a few hundred feet upstream and approximately 1.5 miles downstream from the Blue <br />Flame Mine. This monitoring indicates no adverse impacts to the alluvial water from the Blue Flame <br />Mine. The only surface water from the Blue Flame surface disturbance that would reach Hay Gulch <br />is surface runoff from rain or snowmelt. (As previously discussed, a discharge from the portal area <br />has not occurred.) Surface runoff from the disturbed area can be expected to be alkaline and free of <br />contaminants as there are no leachate-forming materials on the land surface. The quality of this <br />runoff should be closely similar to runoff from surrounding undisturbed lands, and therefore, does <br />not have the potential to degrade surface waters or alluvial water in Hay Gulch. <br />Impacts to Alluvial Valley Floors (AVFs) <br />Hay Gulch meets the regulatory definition of an alluvial valley floor. The essential hydrologic <br />functions of the Hay Gulch AVF are flood irrigation and subirrigation. The only surface disturbance <br />to this alluvial valley floor from the mining operations at the Blue Flame Mine was the construction <br />11 <br />