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• Effects on Groundwater from the Roadside North Portal There are no water rights or springs above the Roadside North Portal (RSN). Dewatering, if any, would drain undeveloped or noncritical aquifers immediately adjacent to the coal seam. The RSN will have minimal impacts to the groundwater resources of the area. Mining in Sections 28, 29, 32 and 33 will be at an elevation higher than the river. Continued in-flows from these areas beyond closure of the mine could create a higher water level in the mine than in the adjacent alluvial water table and have the effect of recharging the alluvial groundwater. The adjacent Cameo mine was primarily mined in Sections 28 and 33 above the river level. The mine was dewatered when the RSN was developed east and north of the old mine. It was estimated that less than 10 gallons per minute was being dewatered from the old Cameo mine through seepage into the RSN. Similar inflows are expected from other mining above the river. These small inflows will have minimal affects upon the groundwater. The mined out area and the adjacent rubblized zone will result in an area of high porosity. This increased porosity will have the effect of rapid dewatering above the resulting mine water level and higher storage capacity below the water level • of the mine. Effects of Groundwater Discharge on the Surface Water Another probable hydrologic effect of mining is discharge of mine water to the Colorado River. The Operator has an existing NPDES (National Pollution Discharge Elimination System) permit through the Colorado Department of Health (i.e. Permit No. CO-0027146). The Operator may discharge mine water from the Roadside South Portal from three outfalls, 001, 002 and 016. The primary discharge point is outfall 016 located at the North Decline. The Norwest Intake outfall is a backup mine discharge point, outfall 002. The South Portal mine dewatering pipe is a second backup point, outfall 001. Additionally, the Operator has outfalls designated for each of the sedimentation ponds, and water quality samples will be taken if and when there is a discharge. I • 19-6 (5103)