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indicates that the wells are relatively shallow. This is important because the wells are completed in a local sandstone (presumed to be the Fish Creek sandstone) which overlies the massive Marine shale. I• Spring and Seep Survey A spring and seep survey was conducted by TCC in the Fish Creek drainage during May 1986. The survey identified all significant discharges to Fish Creek and delineated the specific stratigaphic interval of bedrock discharges where possible. The locations of these discharges are shown on Map 37, Fish Creek Groundwater Inflow Survey. Selected locations were measured for flow, temperature, specific conductance, % salinity, and pH. The field data collected during the survey is shown on Table 60, Fish Creek Stream and Inflow Investigation. Flows were measured using a portable 4-inch cutthroat flume or a bucket and stopwatch. Field water quality was measured using standard instrumentation. The only significant spring identified during the survey issues from the Twentymile sandstone was 20-14, located in Section 11, TSN, R86W. This spring was eliminated from the overall Hydrologic Monitoring program in May, 2003 (TR 03-42). As described above, two springs (SWl & SW2) occur within the north half of section 36, TSN, R87W. The existing monitoring data indicates the springs aze low producers, typically discharging at a rate of 5 gpm or less. The springs appear to issue from the Fish Creek Sandstone. These two springs were added to Twentymile Coal Company's hydrologic monitoring plan and will be monitored on a quarterly basis for quantity and quality. Exhibit 14 has been modified to include these springs. NMD (Panels 17 Right through 23 Right) (PR 03-06) • ~rin~ and Seep Survey Spring and seep surveys of the TCC permit area were conducted by TCC dwing May in 2002 and 2003. The surveys included an investigation of the NMD to identify potential discharges to Fish Creek. The locations of these discharges and other historical discharges can be found on Map 37A, 2003 Spring Survey. Dischazge locations were measured for flow, temperature, pH and conductivity when adequate pooled water was available. The field data collected dwing the survey is shown on Table 60.1, Northern Mining District Spring and Seep Survey. Flows were measured using a portable cutthroat flume or a bucket and stopwatch. Field water quality was measured using standard instrumentation. Generally, groundwater migrates along bedding planes, faults, joints or fracture zones. Given adequate head pressure, if these zones of water migration intercept the surface springs are created. The NMD is located within the Twentymile Park Syncline Basin. The predominant lithologic unit nearest the surface and occupying most of the basin is the Lewis Shale, which can be upwards of 700 feet thick. The lack of significant bedding planes, faulting or fracture zones in this area may account for the lack of springs in the central basin. Seeps observed in the central basin may be the result of surface weathering of the Lewis Shale, which may allow some accumulation of water beneath overbwden resulting in a short period of seepage immediately following spring mnoff. Fish Creek Alluvial Wells Water quality is monitored at several alluvial wells located along Fish Creek. Alluvial wells going downstream include 006AY-1, 006-AZ-3, AVF-13, 006-AW-2 (to be abandoned in 2003), AVF-14, AVF-15, 008-AU-3 and 008- AW-3. Figures 4j through 4q present water quality data (conductivity) for these sites, respectively. Tables 8m through 8t present a summary of period of record water quality data for these sites, respectively. • Water quality data indicates that prior to 1995 there were no significant influences from discharges from disturbed azeas to Fish Creek upstream of alluvial monitoring wells. Water quality is characterized by sodium bicarbonate PR 03-06 2.04-25 05/07/03