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Page 3-66 Environmental Ana/ysis February 2000 Increased groundwater flow potential is expected near fault and fractured zones in all of the water-bearing strata of the area. However, little information is currently available to confirm this, except where mining operations have crossed fault zones. As stated above, the Sanborn Creek Mine experienced peak inflow rates about 2.5 times greater than average rates when crossing faulted zones (Oxbow, 1999). The Bowie mines have been typically dry, even in fractured terrain. 3.6.2.3 Groundwater Quality Bowie and Oxbow have collected groundwater quality data for the past several years. Bowie has long term data from monitoring wells and springs at the Bowie No. 1 Mine on the west side of Terror Creek. Bowie has also collected baseline data from numerous springs and wells near the Bowie No. 2 Mine and within the Iron Point Coal Lease Tract, Oxbow has collected limited baseline data on groundwater quality from their current fee areas for the Sanbom Creek Mine. Baseline data is not available from the Elk Creek Lease Tract area. For the purpose of this document, the water quality data from the Sanbom Creek monitoring sites are assumed to be similar to the Elk Creek Lease Tract. It is important to note that the Oxbow and Bowie laboratory water quality parameters are slightly different and that the groundwater quality discussions vary accordingly. A summary of water quality data is presented in Table 3.6-3, Selected Water Quality Summary - Springs, Alluvial Wells, Drill Holes. Locations of the monitoring sites are shown on Figure 19, Groundwater Hydrology. The following discussion considers average water quality data and parameters that exceed federal primary and secondary drinking water standards (USEPA, 1994). Iron Poinf Exploretion License Area and Coal Lease Tract -The groundwater quality in the Iron Poirit Coal Lease Tract andiron Poiht Exploration License area varies depending on the - geologic unit. The water quality from the alluvial monitoring wells located in the drainages below the Bowie No. 2 Mine (B Gulch and C Gulch) is calcium sulfate type. Water quality is poor with high concentrations of TDS, aluminum, iron, sulfate, and manganese. An alluvial monitoring well installed in the Freeman Gulch (DH-34C) has calcium bicarbonate type water with high concentrations of iron. The groundwater quality of the alluvial wells is similar to the surface water quality in the respective drainages indicating a connectivity between ground and surface water. The high sulfate concentration in ground and surface water of the mine drainages, B Gulch and C Gulch, indicate impacts from past mining activity. Historic waste coal materials and mine portals are located in the B and C gulches below the Bowie No. 2 Mine (personal communication with Greg Hunt, Bowie). Seepage from these sites likely impacts the TDS, sulfate, iron and manganese concentrations in the surface water and associated shallow groundwater. Other monitoring wells are installed in the D coal seam overburden, D coal seam, and Rollins Sandstone. Two wells (DH-39 and 49) are installed in the overburden directly above the D seam. The water quality of these wells is sodium/calcium bicarbonate type with high concentrations of TDS, iron, sulfate, and manganese. The water qualify from the well installed in the Rollins Sandstone (DH-34B) is sodium bicarbonate type with high concentrations of TDS, sulfate, iron and chloride. Water quality from wells installed in the D coal seam is sodium bicarbonate and sodium sulfate type with high concentrations of TDS, sulfate, iron, and manganese.