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• inflow study, Flow rates and filed parameters are recorded for measurable inflows from the accessible areas of the <br />mine. Results of the 1999 survey are presented on Figure 134, 99 Inflow Study Mined Area as of 12/I~. The <br />majority of the mine has been sealed, except that mining progressed in the Northeast Mains opening up new areas <br />to include in the survey. <br />During the year inflows were encountered in the Northeast Submains and the reported high Flow value was <br />approximately 40 gallons per minute. The results are presented on Table 76 and also shown on Figure 134. These <br />flows were encountered as the Submains were driven through the fault. The field conductivity for [he water was <br />measured at 1500 umhos/cm, which is reflective of the Wadge overburden. <br />In November and December 1997 higher Flows were encountered in cross-cut 26 of the 6 Right Ga[eroad. The <br />flows were measured throughout the year and show seasonal variation, with an average annual Flow of <br />approximately I I 1 gpm. The pwnping data are presented on Table 77. The field conductivity was measured at <br />4000 umhos/ctn. It appears the higher flow result from the geological environment within this particular area, i.e. <br />Foidel Creek lineament and steep dip section of anticline. The combination of these feautres appears to have <br />resulted in a setting, which allows for increased pemteability and higher tows <br />In summary, [he inflows encottn[ered in the mine are similar to those reported in prior AHR's. The inflows are <br />within the projected tlo+vs presented in the permit. Water quality ttas not changed significantly and appears [o <br />mirror the quality of the adjacent spoil water. It should be noted that water quality pumped from the Fish Creek <br />• Borehole has changed as elevated EC and iron readings are reposed for [he site. It appears the elevated readings <br />are associated with [he water that has pooled in [he mine sump, and this water has been in contact with the <br />overlying Marine Shale. This contact Itas provided the opportunity for additional salts and iron to be leached from <br />this unit. The pumping of the sump will see a decrease in the elevation of the pool over time, with art anticipated <br />decrease in the EC and concentration of iron in the effluent. <br />FOIDEL CREEK SUBSIDENCE IMPACTS <br />Foidel Creek was undermined and subsided by TCC's mining of the 9Right. 8 Right, 7 Right and to a very <br />limited extent 6Right. Figure 13~ provides the location of the creek in relation to the previously mentioned <br />longwall panels. The figure also reflects the ponding that occurred over the panels. <br />As noted on Figure 135, the largest area of ponding resulted from mining of Panel 7 Right. Pond 4 had the <br />greatest surface area, 3.1 acres, of all of the ponds over the mined area. Field observations indicate that this pond <br />dries up later in the summer. It appears that this is due to the fact that the creek is not deeply incised and after <br />the completion of spring run-off the Hooded areas quickl}• dries as the creek returns to its historic channel. The <br />1999 field observations indicated [hat the area did not flood as extensiveh~ as it did in 1995, and this is most <br />likely associated with how spring run-off occurred, which started earlier and slower allowing for [he water to <br />• dissipate quicker. <br />12 <br /> <br />