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Water quality analysis for the Steven's Gulch well water indicates good <br />quality water, with none of the parameters exceeding the recommended standards <br />of the U.S. Public Health Service. <br />Alluvial/colluvial deposits in the Terror Creek drainage near the Morrell Cow <br />Camp are also being utilized for water supply purposes. However, no impact is <br />predicted for these areas since lands affected by mining lie to the south and <br />east. <br />Occurrences of ground water have been noted in the Mesaverde Formation from <br />information obtained from drilling, experience in the mine and from the <br />presence of springs and seeps in the permit area and hydrologically adjacent <br />area. This information indicates that the only potential regional aquifer in <br />the area is the continuous Rollins Sandstone, located stratigraphically <br />approximately 200 feet below the D coal seam. Recharge to the Rollins <br />Sandstone occurs along outcrops and along subcrops beneath the alluvium of <br />Terror Creek to the east and Steven's Gulch to the southwest. However, due to <br />the steepness of the topography in the outcrop areas (i.e. sandstones are <br />cliff formers) and the narrowness of the stream valleys, the Rollins Sandstone <br />receives little recharge. Some recharge to this continuous unit may come <br />directly from the percolation of snowmelt and precipitation downward through <br />fractures. While no site-specific aquifer characteristics for this unit are <br />available from the permit area, indications are that saturated portions of the <br />Mesaverde Formation are not good aquifers (pages 33 to 37, Section 2.04.7, <br />Volume 1). <br />Ground water occurrences in the stratigraphic interval of the Mesaverde <br />Formation above the D seam are a function of the depositional environment and <br />are characterized by saturated horizons of localized lateral and vertical <br />extent, separated by low porosity, unsaturated intervals. These saturated <br />horizons do not appear to contribute significantly to overall regional ground <br />water flow. <br />To date, the Orchard Valley Mine has experienced maximum inflows of around <br />1,500 gpd. This inflow came from both the floor and roof and were generally <br />roof drips or wet areas on the floor. Mining has progressed below East <br />Roatcap Creek and mine inflows have increased but still remain insignificant <br />to the local hydrologic regime. <br />Inflows from faults and fractures located outside stream valleys (such as in <br />the Orchard Valley Mine) generally dry up with time or flow intermittently at <br />discrete points along the fault or fracture. Those which continue to flow <br />have flow rates which diminish to a trickle. Such inflows may represent the <br />dewatering of lenticular sandstone units with limited recharge areas, or may <br />represent flows through fracture zones extending to the surface which have <br />narrow recharge zones on steep slopes. <br />Surface Water - <br />Surface water information may be found in Volume 1, pages 42 to 47 of <br />Section 2.04, pages 114 to 135 of Section 2.05.6, and in Volume 4. Water <br />rights tabulations and an augmentation plan are found in Volumes 5 and SA. <br />Annual hydrologic reports have been prepared since 1982 and exist as stand- <br />alone volumes. For a description of the surface water hydrology of the mine <br />-14- <br />