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1999 to September 2000. During the inflow study, flow rates and filed parameters are recorded for measurable inflows from [he accessible areas of the mine. Results of the 2000 survey are presented on Figure 134, 2000 Inflow Study Mined Area as of 12/31. The mining is almost complete in the Eastern Mining District, with the longwall move scheduled for late December or early January. During 2000 development work has been completed in the 11 and 12 Right Gateroads, and limited mining in [he 13 Right Gateroad and the Northwest Mains. As can be seen on Figure 134 the majority of the previously mined areas are sealed, and it is anticipated that the Eas[em Mining District will be sealed during 2001. During the year inflows continued in the Northeast Submains and the reported high flow value was approximately 15 - 20 gallons per minute, which is less than reported in 1999. The results are presented on Table 76 and also shown on Figure 134. The field conductivity for the water was measured at 1500 umhos/cm, which is consistent with [he 1999 measurement. As presented previously, in November and December 1997 higher Flows were encountered in cross-cu[ 26 of the 6 Right Gateroad. The flows were measured throughout the year and show seasonal variation, with an average annual flow of approximately 65 gpm. The pumping data are presented on Table 77. The field conductivity was measured at 3800 umhos/cm. It appears the higher flow result from the geological environment within this particular area, i . Fotdel Creek lineament and steep dip section of anticline. The combination of these features appears to have esul[ed in a setting, which allows for increased permeability and higher flows \\ in~~,Gn wo~• .., ~/ocr ~/oo><~~. ~ ...~,~,~ [ 2000,~...,l~na~,..,i\ • In summary, the inflows encountered in the mine are similar to those reported in prior AHR's. The inflows are J within the projected flows presented in the permit. Water quality has not changed significantly and appears to mirror the quality of the adjacent spoil water. It should be noted [hat water quality pumped from [he Fish Creek Borehole has changed as elevated EC and iron readings are reported for the site. It appears the elevated readings are associated with the water that has pooled in the mine sump, and this water has been in contact with the overlying Marine Shale. This contact has provided the opportunity far additional salts and iron to be leached from this unit. The pumping of the sump will see a decrease in the elevation of the pool over time, with an anticipated decrease in the EC and concentration of iron in [he effluent. FOIDEL CREEK SUBSIDENCE IMPACTS Foidel Creek was undermined and subsided by TCC's mining of [he 9Right, 8 Right, 7 Right and to a very limited extent 6Right. Figure 135 provides the location of the creek in relation to [he previously mentioned longwall panels. The figure also reflects the ponding that occurred over the panels. As noted on Figure 135, the largest area of ponding resulted from mining of Panel 7 Right. Pond 4 had the greatest surface area, 3.1 acres, of all of the ponds over the mined area. Field observations indicate that [his pond dries up later in the summer. It appears that this is due to [he fact that the creek is not deeply incised and after the completion of spring run-off the Flooded areas quickly dries as the creek returns to its historic channel. The • 2000 field observations indicated that the area did not flood as extensively as it did in 1998, and [his is most likely associated with [he timing of spring run-off. 12