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Probable Hydrologic Consequences <br />Ground Water Effects <br />The ground water-bearing units having the greatest potential to be affected by mining <br />at the King I and II Mines are the Hay Gulch alluvium, the Menefee Formation, and <br />the Cliffhouse Sandstone. (The Point Lookout Sandstone is well beyond the azea of <br />influence of the mines because it is approximately 250 feet stratigraphically below the <br />workings. The Point Lookout has been monitored since late 2000 in the Haugen well <br />about 5000 ft. down-dip from the workings. Monitoring data show no impacts from <br />mining at the King I and II Mines.). <br />Hay Gulch Alluvium -The mine will not discharge enough water to the Hay Gulch <br />alluvium to impact the alluvium. The Hay Gulch alluvium has been monitored in the <br />Wiltze well, downstream from the west sediment pond at the King I Mine. <br />Monitoring data indicate no mining impacts to this unit. The King II Mine will also <br />monitor alluvial water quality in adown-gradient well. <br />Cliffhouse Sandstone - It appears unlikely that the King I and II Mines will fill with <br />water after mining is finished. With the exception of one inflow event, the mine <br />workings of the King I Mine have been dry. Both mines appear to underlie the updip, <br />unsaturated portion of the Cliffhouse Sandstone. Impermeable shale and siltstone of <br />the Menefee Formation underlie the workings, and also are unlikely inflow sources <br />for the workings. If the King I Mine or King II Mine workings were to eventually fill <br />with water, it seems unlikely the water could be transmitted from the workings to the <br />Cliffhouse Sandstone through intergranulaz porosity in roof rock of the workings <br />because the roof rock is composed of shale, which probably is impermeable to water. <br />(Drill hole sample logs in Appendix 4 of the permit show the Upper Coal Seam of the <br />Menefee Formation, the seam mined at the King I Mine, is bounded above and below <br />by shale.) Subsidence fractures in the roof rock, however, could provide a conduit of <br />flow for water from the workings to the overlying Cliffhouse. Therefore, if the <br />workings fill with water, and subsidence fractures convey that water to the Clifthouse <br />Sandstone, then impacts could possibly occur to the water quality in the Cliffhouse <br />Sandstone aquifer down-dip from the workings, if mine water is lower quality than <br />ambient ground water. Significant flow from the workings to the Cliffhouse through <br />subsidence fractures is unlikely, however, because head in the overlying (higher <br />elevation) Cliffltouse would be greater than the head exerted by the mine water. The <br />State Engineer's records show two wells have been completed in the Cliffhouse <br />Sandstone approximately one mile downgradient from the King I Mine workings (the <br />V. Paulek and G. Paulek wells). <br />Menefee Formation -Like the Cliffhouse Sandstone, mining impacts to the Menefee <br />Formation aze improbable because it is unlikely the workings of the King I and II <br />Mines will fill with water. <br />Ground water points of compliance are not warranted for the Hay Gulch alluvium, the <br />17 <br />