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` Tcital Suspended Solids z Iron s Settleable Solids 3. Potential Effects on Ground Water The mine's operations have affected and will affect bedrock ground water of one formation, the Williams Fork Formation. The Williams Fork contains the ten coal seams to be mined and is the surface outcrop on the permit azea. Ground water within the pemut azea occurs under perched conditions in the interbedded and lenticulaz sandstones of the Williams Fork Formation. These sandstones aze predominately fine to medium grained, poorly sorted and calcareous. The thickness of the sandstones is estimated to be 1,600. feet. There is no continuous; regional ground water system on the property within the stratigraphic section of the Williams Fork Formation. This was documented in the 1979 report prepazed by Leomard Rice Consulting Water Engineers' study (LRCWE}_ The report concluded that there was an absence of ground water from the site (see Extul~it TA of the Permit}..In addition, ITtesthoIes were dnTied and then corresponding records collected when the property was originally explored. All well data confirmed that where water was encountered, it was limited both vertically and laterally and encountered under perched conditions. For further information on the well test data, see pages 2.04.7-5 and 6 of the PAP. 'There is little development of the.graund water resource in the. local.area_ The few wei1S that. . . have been completed in the Williams Fork interbedded sandstones yield less than five gallons per minute and their uses aze limited to domestic and/or livestock use. Neazby residents haul drinking watersuppliesfroraCraig.andll4eeker.. Saturation of the Williams Fork sandstones is weak to nonexistent, with the flow controlled by the geologic structure of the Cotlum Syncline in a downdip direction. Ground water direction follows the geologic structural trend and flows to the northeast. Following the downdip direction, where the ground water flow meets the land surface, infrequent discharges from the Williams Fork formation are seen as seeps and springs on the valley walls of Goodspring and Taylor Creeks. Further analysis of the Goodspring and Taylor Creek basins show the recharge rate to be 0.2 to 0.35 inches per yeaz from the Williams Fork surface outcrop area (PAP, page 2.04.7-11). Anmial precipitatioa.variesfiom year to yea;, and due to topography and.elevatiorx changes, varies even across the permit area. Precipitation averages 21.5 inches (PAP, Page 2.04.7-I), but has been recorded at less (12.45 to 18.6 at the Permit area during 1978-1980) (PAF, Table 7, page 2.04.8-1 I). The Iles Formation, of varying thickness, is located beneath the Williams Fork Formation (and the coals to be mined). The Trout Creek Sandstone, a regional aquifer reaching thickness of up to 75 feet, is located within the Iles Formation. The Trout Creek sandstone is fine, well sorted, calcareous, and is a continuous unit that can be correlated over a lazge azea. It is mainly from this sandstone member that the two creeks on the permit azea, Goodspring and Taylor, receive their flow. The Trout Creek Sandstone is believed to contain water due to a saturation zone found October 21, 2002 31