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that the Blue Flame site is not contributing more suspended solids to offsite streamflow or runoff than premining conditions. Evaluation of Hydroloaic Impacts Required by Section 3.03.2(2) Rule 3.03.2(2) requires the Division to evaluate hydrologic impacts prior to releasing reclamation liability. This evaluation must consider whether pollution of surface or subsurface water is occurring, and the probability of future occurrence of such pollution. The Division's evaluation is summarized below. Cround Water Impacts - As shown in Figure 1, the underground workings of the Blue Flame Mine aze above the current ground water saturated zone. The elevation of the top of the saturated zone is considered to be stabilized at its approximate current position. Only a significant long- term change in regional climate would significantly raise or lower this elevation. Over time, meteoric water probably infiltrates from the land surface down into the abandoned underground workings of the Blue Flame Mine. As this water accumulates in the workings, it would seep into the bedrock walls of the workings, and migrate downgradient to the saturated zone. The expected migration direction would be generally southward from the workings. Any minerals this migrating water has picked up in the mine workings would be carried to the saturated zone. If the mineral content of this migrating water is high, then it could pollute the ground water in the saturated zone. The infiltration and migration process would take several decades owing to the low hydraulic conductivity of the Cliff House Sandstone and Menefee Formation. It is improbable that any water from the Blue Flame workings has reached the saturated zone, yet. Also, it is improbable that the Blue Flame workings have discharged water to the land surface in the portal area because it would take many decades to fill the workings up to the portal area. No seepage or discharge from the portal area has been found during the Division's regulaz inspections. The improbability of current degradation to the saturated zone, and the absence of discharges from the portal, indicate the Blue Flame Mine is not causing ground water pollution, and the operation is in compliance with the Basic Standards for Ground Water (Colorado Water Quality Control Regulation 41.S.C.6). Surface Water Impacts -The only surface water feature that would receive surface runoff from the Blue Flame surface disturbance is Hay Gulch. The Gulch does not have a stream channel An irrigation ditch flows through the bottom of the Gulch. The only surface water from the Blue Flame surface disturbance that would reach Hay Gulch is surface runoff from rain or snowmelt. (As previously discussed, a discharge from the portal area has not occurred.) The volume ofrunofffrom the disturbed azea is small because this area covers only 4.1 acres. Surface runofffrom the disturbed area can be expected to be alkaline and free of contaminants as there are no leachate-forming materials on the land surface. The quality of this runoff should be closely similar to runoff from surrounding undisturbed lands, and therefore, does not have the potential to degrade surface waters or alluvial water in Hay Gulch. 2