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<br /> <br />Requirement <br />Require- <br />ment <br />citation Require- <br />ment <br />complied <br />with ? <br />es / no <br /> <br />Comment <br />Z. Agreement CDMG <br />of observed regulation <br />hydrologic 2.05.6(2) <br />impacts with and <br />"probable requireme <br />hydrologic nt to keep yes <br />consequences informatio <br />" (PHC) n current, <br />projected in CDMG <br />mining regulation <br />ermit 2.03.3(1) <br /> Mining impacts to the C1iflhouse Sandstone cannot be definitely <br /> ruled out because the Clifthouse is not monitored downgradient <br /> from the King Coal Mine. The potential for impacts to the <br /> Clifihouse is of interest because the sandstone may be used as an <br /> aquifer near the mine. The State Engineer's records show two <br /> wells have been completed in the Cliflhouse Sandstone <br /> approximately one mile downgradient from the mine workings (the <br /> V. Paulek and G. Paulek wells). <br /> If the King Coal Mine workings eventually fill with water, it <br /> seems unlikely the water could be transmitted from the workings to <br /> the Cliffhouse Sandstone through intergranular porosity in roof <br /> rock of the workings because the roof rock is composed of shale, <br /> which probably is impermeable to water. (Drill hole sample logs in <br /> Appendix 4 of the permit show the Upper Coal Seam of the <br /> Menefee Formation, the seam mined at King Coal, is bounded <br />AA. Ade uac <br />q y above and below by shale.) Subsidence fractures in the roof rock, <br /> <br />of ground <br />CDMG however, could provide a conduit of flow for water from the <br />water regulation yes workings to the overlying Cliffhouse. Therefore, if the workings <br />monitoring 4.05.13(1) fill with water, and subsidence fractures convey that water to the <br />program Cliffhouse Sandstone, then impacts could possibly occur to the <br /> water quality in the Clitifhouse Sandstone aquifer downgradient <br /> from the workings, if mine water is lower quality than ambient <br /> ground water. <br /> As explained in item T, above, it appears unlikely the King Coal <br /> Mine will ever fill with water. The mine appears to underlie the <br /> updip, unsaturated portion of the Cliffllouse Sandstone. <br /> Impermeable shale and siltstone of the Menefee Formation underlie <br /> the workings, and also are unlikely inflow sources. Based on the <br /> continued dry outlook for the workings, a monitoring well is not <br /> warranted in the Cliffliouse Sandstone downgradient from the <br /> mine. Such a well could be warranted, however, if the mine <br /> encounters significant water inflows. <br /> A regional aquifer about 250 ft. stratigraphically below the mine <br /> workings, the Point Lookout Sandstone, has been monitored since <br /> late 2000 in the Haugen well about 5000 ft. downgradient from the <br /> workin s. Data show no impacts from mining at King Coal. <br />Page 5 <br />