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SPRINGS AND SEEPS
<br />• A spring and seep survey was conducted by TCC in the Fish Creek drainage during May 1986. The survey
<br />identified all significant discharges to Fish Creek and delineated the specific stratigraphic interval of bedrock
<br />discharges, where possible. The locations of these discharges are shown on Map 37, Fish Creek Ground Water
<br />Inflow Survey. Selected locations were measured for flow, temperature, specific conductance, percent salinity,
<br />and pH. The field data collected during the survey is shown on Table 60, Fish Creek Stream and Inflow
<br />Investigation. Flows were measured using a portable 4 -inch cutthroat flume, or a bucket and stopwatch. Field
<br />water quality was measured using standard instrumentation.
<br />The only significant spring identified during the survey was 20 -14, which issues from the Twentymile sandstone
<br />and is located in Section 11, T5N, R86W. This spring was eliminated from the overall Hydrologic Monitoring
<br />program in May, 2003 (TR03 -42).
<br />The spring and seep survey, previously referenced, indicated two springs or seeps that could be affected by
<br />planned mining operations. The two springs, located in the north half of Section 36, T5N, R87W appear to issue
<br />from the Fish Creek Sandstone, and were undermined in the SWMD. Monitoring data indicates the springs
<br />produce limited discharge, typically discharging at a rate of 5 gpm or less, and were not affected by mining. These
<br />two springs were added to TCC's Hydrologic Monitoring Plan, and were monitored during and following active
<br />mining, on a quarterly basis for quantity and quality. Exhibit 14 was modified to include these springs.
<br />NMD and WMD (Panels 17 -Right through 24 -Right and 12 -Left through 17 -Left, PR03 -06, PR06 -07, and
<br />PR09 -08)
<br />Supplemental Spring and Seep Survey
<br />• Supplemental spring and seep surveys of the TCC permit area were conducted by TCC during May, in 2002 and
<br />2003. The surveys included an investigation of the NMD and WMD areas to identify potential discharges to Fish
<br />Creek. The locations of these discharges and other historical discharges can be found on Map 37A, 2003 Spring
<br />Survey. Discharge locations were measured for flow, temperature, pH and conductivity when adequate pooled
<br />water was available. The field data collected during the survey is presented on Table 60.1, Northern Mining
<br />District Spring and Seep Survey. Flows were measured using a portable cutthroat flume or a bucket and
<br />stopwatch. Field water quality was measured using standard instrumentation.
<br />Generally, groundwater migrates along bedding planes, faults, joints or fracture zones. Given adequate head
<br />pressure and recharge, if these zones of water migration intercept the ground surface, springs or seeps develop.
<br />The NMD and WMD are located within the Twentymile Park synclinal basin. The dominant near - surface
<br />lithologic unit, which occupies most of the basin is the Lewis Shale, which can be upwards of 700 feet thick. The
<br />lack of significant bedding planes, faulting, or fracture zones in this area, may account for a general lack of springs
<br />or seeps in the central basin. In general, as documented by Table 60. 1, any springs or seeps identified by the spring
<br />and seep survey in the central basin are characterized by seasonal, low- volume flows, that may vary significantly
<br />from year to year dependent primarily on snowfall levels and the rate of spring snowmelt. Given the survey data
<br />and field observations, essentially all of the identified springs and seeps probably result from infiltration of
<br />snowmelt, and resulting shallow ground water flows along zones of lower permeability, to the point where these
<br />zones daylight on the sides of hills or in the numerous small ephemeral drainages in the area. Flows are typically
<br />of limited duration, drying -up within 30 to 60 days of snowmelt.
<br />Fish Creek Alluvial Wells
<br />Water quality is monitored at several alluvial wells located along Fish Creek. Alluvial wells going downstream
<br />include 006AY -1, 006 -AZ -3, AVF -13, 006 -AW -2 (to be abandoned in 2003), AVF -14, AVF -15, 008 -AU -3 and
<br />• 008 -AW -3. Figures 4j through 4q present water quality data (conductivity) for these sites, respectively. Tables 8m
<br />through 8t present a summary of period of record water quality data for these sites, respectively.
<br />PR09 -08 2.04 -25 09/15/09
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