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<br />These long-term data records are necessary to identify any pattern of <br />water quality changes. Energy Fuels Coal Company's hydrologic monitoring <br />plan should be adequate to plan for modification of surface or <br />underground mining activities, if necessary, to minimize disturbances to <br />the prevailing hydrologic balance (Rule 4.05.13(1 )(b )), <br />The Southfield Mine workings have the potential to deplete the quantity <br />of groundwater through mine-induced groundwater inflows. The mining <br />operation will induce inflows by dewatering the coal seam and the <br />associated roof and floor strata as the mine workings advance. In <br />addition, overlying aquifers could be dewatered through <br />subsidence-related fractures. Locally perched groundwater aquifers in <br />strata above the workings may be dewatered through subsidence cracks or <br />fractures. Thus the water will drain down through the fractures to the <br />voids created by the mine. <br />The greatest potential effect on groundwater is for perched aquifers in <br />the Vermejo and the overlying Raton Formations to be dewatered by <br />subsidence. Wells which use these perched aquifers could experience <br />drawdown effects. However, due to the low hydraulic conductivity of the <br />aquifers, the fact that aquifers in this area tend to be laterally <br />discontinuous, and the effects of past surface and underground mining, <br />groundwater impacts (both magnitude and extent) are difficult to <br />predict. The operator is obligated to comply with Rule 4.05,15 <br />pertaining to water rights and replacement if an owner is injured as the <br />result of the operation, The groundwater monitoring plan has been <br />designed to identify groundwater impacts before they extend to water <br />supply wells, These measures will ensure a better understanding of the <br />impacts to the groundwater system and protection of water resources in <br />the future. <br />The existence of the mine workings will permanently modify the pattern of <br />groundwater flow. The flooded mine constitutes a region of essentially <br />infinite permeability that will tend to cause groundwater to <br />preferentially pass through the workings. The water passing through the <br />flooded mine may be degraded in quality, relative to that in the <br />undisturbed strata. <br />Another potential groundwater impact due to subsidence would be <br />fracture-related drainage of surface water bodies. These surface water <br />bodies would be the mine water ponds, ephemeral drainages, and the <br />perennial Newlin Creek. Dewatering the ponds would short-circuit the <br />water system during mining, which is not considered a significant <br />impact. Also, the effects to ephemeral drainages would be minimal. <br />However, diverting stream flow of Newlin Creek underground may be <br />significant. The interception of surface water or shallow groundwater by <br />underground workings presents a potential impact to water availability in <br />Newlin Creek. However, as previously mentioned, Newlin Creek is diverted <br />upstream of the mine by the City of Florence. This reduces the <br />significance of any depletion of the creek due to the mine. <br />-14- <br />