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West Etk Mine fault systems encountered in the Rollins Sandstone below the B-Seam. Amore • thorough discussion of these fault systems can be found later in this section. There are no domestic, irrigation, stock, commercial or industrial groundwater wells within the permit area. This lack of wells adequately reflects the resource potential of the groundwater beneath the mine property, with the exception of the fault systems described in this section. The CHIA, Jumbo Mountain Decision Document, and the West Elk Mine permit, including revisions and renewals, stress the lack of groundwater (and groundwater use) at the mine and surrounding properties. Domestic water for mine use is supplied by surface water from the North Fork. There are essentially three ways in which mining activities at West Elk Mine can affect groundwater quantity. These include: (1) the construction of mine entries, (2) the direct mining of the coal, including the effect of roof collapse and mine subsidence on water-bearing formations above the coal, and (3) the storage of water in previously mined and sealed portions of the mine. These are discussed in turn. Construction of Mine Entries Access to the B-Seam is by two sloped entries driven from the F-Seam South Main Intakes. Access to mining within the current permit and Box Canyon permit revision areas, and subsequent mine development, is also planned via these same sloped entries. • Mine exhaust air is currently routed westward through the B-Seam to the Lone Pine ventilation fan, as well as through the F-Seam, via an inter-seam ventilation raise, then to the Sylvester Gulch ventilation fan. Mine intake air enters the mine at three locations: (1) F-Seam Portals, (2) Lone Pine Portals, and (3) Shaft #3 in Sylvester Gulch. Major ventilation facilities are currently under construction in Sylvester Gulch, and further described in Exhibit 69. Two large diameter shafts will serve future intake and return ventilation needs for B-Seam and E- Seam mining. No significant groundwater was encountered during slope or shaft excavation. Aerial photo studies coupled with subsurface structural data indicate the entry slopes and ventilation shaft are not located in an area which has significant fracture zones and, as such, significant inflows have not been induced. The F-Seam South Main Intakes were completed in 1982 and consist of five entries. Prior to construction of these entries and as an effort to enhance MCC's understanding of the area groundwater system, piezometers were installed in the colluvial/landslide strata immediately upslope of the entries. Based on data from construction of these piezometers, the thickest saturated stratum appeared along Entry No. 4 (numbered east to west). The colluvium over Entry #2 and #3 exhibited only a thin saturated thickness which dried up that summer and fall. • Entry construction began near the end of September 1981. During the period August 20, 1981 to December 12, 1981 some piezometer water levels dropped a maximum of 2 feet above the 2.05-211 Revised Jun. 1995 PRO6: Rev~sedNav. 1998 TR80; l/98 PR08