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• • Hydrologic Dam fnrerprcrarion and Impact A.csectrnem /or the Permit and Adjacent Arcar As expected, water was encountered in the sub- main. Some water was anticipated because colluvi- um overlays this submain. In addition, cover over the area is low to moderate. Although the submain was wet and Moors were muddy, the inflows were not measurable. Panel NWiS During 1990, WECC began developing this panel to the southwest from the Northwest Submains. This development will continue in 1991. Also, the 2 Northwest Submain will be developed from this panclin 1991. Water conditions in this panel were similar to those encountered in the 1 Northwest Submain. Most of the developed area was we[ and muddy. Also, none of the inflows were measurable. "B" Seam Siopes WECC began developing "B" seam access and ventilation during 1990. Two parallel sloped entries wcrc completed to provide access to the "B" seam from the "F' seam. Once in the "B" seam, two crosscuts wcrc developed south and cast to the ventilation raise site. Work on the raise was almost complete by the end of 1990. No significant water was encountered during this initial development of the "B" seam. The "B" seam itself turned out to be the wettest of the three areas. Roof drippers occurred following develop- ment. Water from immeasurable drippers in one arcs associated with a small fault at the bottom of the slopes continues to accumulate in a sump area. WECC anticipates minimal inflows from continued development of the "B" scam. Based on overbur- den conditions, only minimal inflows should occur. Furthermore, (lows encountered during initial development of the "B" seam were minor. Except for the fault-associated drippers, (lows were not measurable and subsequently dried up. Water Quality Samples taken during 1990 indicate water quality in the mint to be good. Accordingly, it should pose no problem for discharge. The discharges should readily meet NPDES effluent limitations after settling and should not measurably impact receiv- ing waters. Quality of water discharged in 1991 should be similar to the 1990 values shown in Table 5. 11 Groundwater Some groundwater wells exhibited slightly changed conditions in some instances and the subsidence monitoring deep wells showed some in0uencc from mining. Overall however, the wells remained fairly constant compared to previous years. Most notably, the 1990 data indicate: • Refuse area wells SG-1 and GP-1 continued to show lower levels than in years previous to 1987. This is due to persistent lower precipi- tation paucrns. • Refuse arcs wells GP-3 through GP-5, as in previous years, contained no water. • Barren Member well 38-H-I, as previously described, was affected by subsidence. This well has since recovered to nre-minine water levels. • Barren Member well 38-H-2 continued to have casing blockage problems which oc- curred after it was installed. Very little data were collected at this well due to the prob- lem. The casing was apparently damaged by subsidence as described earlier in this section. • Barren Member well 38-H-3 provided no useful well data in 1990. Moisture problems with the casing and later communication with the mine workings, probably caused by subsi- dence, precluded the determination of water levels.