Laserfiche WebLink
2.04.3(11 <br />"D" and "E" coal seam subcrop below this alluvial material in the <br />area west of the mine entrance. These subcrops are covered by as <br />•- much as 175 feet of this highly permeable aquifer material. Due <br />to the fractured nature of the coal seams and the direct contact <br />of these fractures to the saturated alluvial material, there will <br />be direct induced recharge from the aquifer when this coal material <br />is excavated. However, as evidenced by the Electric Logs - "E" <br />Coal Seam !dap, 2.04.5-3a, and the Electric Logs - "D" Coal Seam <br />idap, 2.04.5-3b, and driller's log included in Figures 2.04.5-16, <br />2.04.5-17, 2.04.5-18, 2.04.5-19, 2.04.5-20, 2.04.5-21, 2.04.5-22, <br />2.04.5-23, 2.04.5-24; and 2.04.5-25, the "D" and "E" coal seams are <br />both overlain by impervious material such as claystone and silts tone. <br />Due to the impervious nature of these materials, as soon as the coal <br />seams are buried a few feet, they are essentially isolated from <br />overlying groundwater. This was personally observed in the present <br />workings of ttie "E" coal seam where a dry roof exists in most areas. <br />Therefore, the areas of most concern and influence upon alluvial <br />groundwater will be within 100 to 400 feet of the subcrop of both <br />"D" and "E" coal seams. <br />• The Geology tSap, 2.04.5-1, showing the general geology and location <br />of all wells in the area, illustrates that only three wells exist <br />within the potentially affected area near the subcrops of the "D" <br />and "E" coal seams. These include the Carson Well, southwest <br />quarter, Section 11. At the present time, Grand Mesa Coal Company <br />holds title to the Gentry and Ewing properties, therefore the only <br />well which may be effected by mining "D" coal is the Carson well. <br />If this well is in fact completed in the "D" coal seam (a log of <br />this well is not presently available), mining of the "D" coal could <br />adversely affect the Carson well. However, if the Carson well is <br />producing from the alluvial material above the "D" coal seam, this <br />well should not be adversely affected, due to the large storage <br />capacity and permeability of the alluvium. <br />Because all additional wells up gradient and down gradient from <br />ghe subcrop area are located and completed in zones vertically and <br />horizontally some distance from the subcrops, no serious adverse <br />• effects are forseen. Any induced recharge caused by mining coal <br />seams will be of relatively small quantity, and the water available. <br />REVISED May 8, 1.981 49 <br />