2011-01-13_REVISION - C1981038 (8)

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Alluvial/colluvial deposits in the Terror Creek drainage near the Morrell Cow Camp are also being utilized for water supply purposes. However, no impact is predicted for these areas since lands affected by mining lie to the south and east. Occurrences of ground water have been noted in the Mesaverde Formation from information obtained from drilling, experience in the mine and from the presence of springs and seeps in the permit area and hydrologically adjacent area. This information indicates that the only potential regional aquifer in the area is the continuous Rollins Sandstone, located stratigraphically approximately 200 feet below the D coal seam. Recharge to the Rollins Sandstone occurs along outcrops and along subcrops beneath the alluvium of Terror Creek to the east and Steven's Gulch to the southwest. However, due to the steepness of the topography in the outcrop areas (i.e. sandstones are cliff formers) and the narrowness of the stream valleys, the Rollins Sandstone receives little recharge. Some recharge to this continuous unit may come directly from the percolation of snowmelt and precipitation downward through fractures. While no site-specific aquifer characteristics for this unit are available from the permit area, indications are that saturated portions of the Mesaverde Formation are not good aquifers (pages 33 to 37, Section 2.04.7, Volume 1). Ground water occurrences in the stratigraphic interval of the Mesaverde Formation above the D seam are a function of the depositional environment and are characterized by saturated horizons of localized lateral and vertical extent, separated by low porosity, unsaturated intervals. These saturated horizons do not appear to contribute significantly to overall regional ground water flow. When in operation, the Bowie No. 1 Mine had experienced maximum inflows of around 1,500 gpd. This inflow came from both the floor and roof and were generally roof drips or wet areas on the floor. Mining progressed below East Roatcap Creek and mine inflows increased but still remained insignificant to the local hydrologic regime. The portals of the East Mine were sealed in 2001 and the portals at the West Mine were sealed in 2000, so no recent mine inflow information is available. Inflows from faults and fractures located outside stream valleys (such as in the Bowie No. 1 Mine) generally dry up with time or flow intermittently at discrete points along the fault or fracture. Those which continue to flow have flow rates which diminish to a trickle. Such inflows may represent the dewatering of lenticular sandstone units with limited recharge areas, or may represent flows through fracture zones extending to the surface which have narrow recharge zones on steep slopes. Surface Water - Surface water information may be found in Volume 1, pages 42 to 47 of Section 2.04, pages 114 to 135 of Section 2.05.6, and in Volume 4. Water rights tabulations and an augmentation plan are found in Volumes 5 and 5A. Annual hydrologic reports have been prepared since 1982 and exist as stand- alone volumes. For a description of the surface water hydrology of the mine permit area and a discussion of the impacts of mining on surface water, please refer to the Hydrologic Balance and Probable Hydrologic Consequences portions of Section B of this document. BRL's baseline surface water collection for the permit area consisted of reviewing existing baseline studies on the area, compiling a list of water rights on file with the State Engineer, identifying water resources using aerial photographs, and actual on-the-ground surveys. In the 1988 Findings, only one concern with the baseline study that pertained to a proposed area to be mined outside that five-year permit term was noted. CWI had not obtained right of entry to conduct on-the-ground baseline surveys on two tracts of land totaling 286 acres within the East Roatcap Creek drainage basin. COVCC obtained the required rights of entry during 1992-93 and performed ground reconnaissance for surface water sources on these areas as baseline data for Permit Revision No. 3. 15