Laserfiche WebLink
undisturbed flow at the underground development waste disposal site will <br />also be stable under the 10-year, 24-hour peak flow conditions. <br />Central Facilities Area Collection Ditches, Culverts and Diversions <br />The collection ditches and culverts conveying runoff from the disturbed <br />areas at the central facilities area will adequately carry the flow <br />resulting from the 10-year, Z4-hour event. The ditch collecting <br />disturbed flow and diverting undisturbed flow at the coal processing <br />waste disposal site will also be stable under the 10-year, 24-hour peak <br />flow conditions. <br />Munger Creek Permanent Stream Channel Relocation <br />The combination channel, bank, and floodplain configuration of the <br />relocated stream channel will safely pass the peak runoff of a 100-year, <br />24-hour precipitation event. The capacity of the reconstructed channel <br />will be at least equal to the capacity of the unmodified channel <br />immediately upstream and downstream of the reconstructed channel. <br />These components of the surface drainage system are in compliance with <br />the Rules and Regulations. <br />Ground Water-Rules 2.04.5, 2.04.7, 2.05.6(3) and 4.05 <br />Information provided by the applicant with respect to ground water in the <br />permit area can be found in Sections 2.3.2, 2.6, and 4.4 in Volume I and <br />Sections 2.3.9, 2.4.4, and 4.2 of Volume VI of the application. Based on <br />an analysis of these data and information, the following determinations <br />have been made by the Division: <br />Drilling in the area indicates the presence of a saturated zone within <br />the Cameo seam (Figure 4.4-1). This saturated zone occurs outside of the <br />permit area within the Munger Canyon Mine plan area and will not be <br />encountered by projected mining within the Munger Canyon Mine. Data <br />indicates that the Carbonera seam, which overlies the Cameo seam, also <br />becomes progressively saturated to the northeast of the five-year permit <br />area. The zone of saturation in the Cameo seam is probably recharged at <br />the point where the Cameo seam subcrops below the East Salt Creek <br />alluvium, approximately three miles upstream of the mine. Very little <br />recharge of water in coal seams and sandstones will occur along the <br />outcrops due to the low annual precipitation rate (8.8 inches) and the <br />steep slopes which favor runoff over infiltration. <br />The applicant has no monitoring well completed in strata overlying the <br />underground mine workings. This is because of the inaccessibility of the <br />characteristically steep terrain of the "Book Cliffs" region to <br />truck-mounted drill rigs. Previous explorations drill holes in the area <br />of the McClane Canyon Mine have been dry to a depth in excess of 200 feet <br />below the Cameo seam. The Cameo seam's associated roof and floor strata <br />are not saturated in the area of the mine. The mine is not a recharge <br />area for these strata (see Figure 4.4-1 and Appendix G). The Munger <br />Canyon Mine is located updip of the McClane Canyon Mine, which suggests <br />that a similar situation will occur. <br />-25- <br />