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• r 1 U N~olo@e Dena huvp~eradon and bnpaa A~a®nau Jar the Permit andAdjacov.Lear "F" Seam 1st West Submain Seals were constructed between the crosscut of the; 1WSS panel bleeder and the 2W1N panel bleeder' (inby crosscut 28). Three rows of pillars were left to protect the bleeders. Also, the southern-most row of pillars was left in the 1st West Submain. The rest of the 1St West Submain was retreat mined to crosscut 10. Panel 1W1S in this panel during development or retreat. How- ever, flow from panel I W2S appeared on the Door of the 1st West Submain near the 1WZS seals shortly after secondary mining was completed. During the 4th quarter of 1987 Dow was estimated at 3 to 5 gpm. The Dow increased to 5.5 gpm and 9.8 gpm during the 1st and 2nd quartets of 1988, respectively. Since this time the flow declined steadily, to 1.2 gpm during the 3rd quarter of 1988 and to an unmeasutable amoun[ by the end of 1988. During 1989 the area outside the panel seals dried up completely. The area has remained dry since. Monitoring of well 38-H-1 during the 1991 water year indicates well water levels were still at pre- mining levels. The water level in this well dropped about 100 feet from January to July 1987 while retreat mining waz occurring (November 1986 to March 1987). Well 38-H-1 is screened at three 20- foot intervals midway between the surface and the "F' seam coal. The "F' seam depth of Dover is about 1000 feet at the 38-H-1 well loption and averages about 900 feet over this panel. The total depth of well 38-H-1 is 580 feet No water was observed in the mine during devel- opment or retreat mining. No in-mine Dows have been observed since. Water observed in adjacent areas waz thought to be coming from panel 1 W2S because it did not appear until retreat mining occurred in panel 1W2S. During 1990, water levels in well 38-H-1 remained near pre-mining levels. Thus, data from we1138-H-1 indicete groundwater in the barren member above the rubble wne will not suffer long-term impacts from secondary mining. Wells 3~H-2 and 38-H-3 provided little ttseful information (see hydrographs in Appendu I). Subsidence apparently damaged the casings o[both wells and connected them with the mine ventila- tion system. In well 38-H-2 the casing was ob- structed at 415 feet below the surface. Panel 1W2S Retreat mining of panel 1W2S waz completed in November, 1987. Very little water was enwuntered Panel 1W3S Development mining in panel 1W3S began in March, 1987. Wet and damp roof areas were encountered from apprordmately 11 crosscut to 24 crosscut These wet areas (roof drippers) produced very little Dow but were fairly extensive over a wide area. Some were associated with a badly fractured immediate mine roof (overburden averages about 700 feet). The water is probably azsociated with sandstone channels directly above the coal seam and with Lone Pine Gulch features. Retreat mining was completed during September 1988. To date, no evidence of water is visible near the panel seals or in adjacent areaz. Panel 1W4S Development mining began in panel iW4S during October 1987. The "F' seam depth of cover aver- ages about 500 feet over this panel. Roof drippers and wet areas were encountered in roof fractures and near the sandstone channel margins. The wet areas were not az large az those present in panel 1W3S and did not produce any measurable flows. No significant Dows were encountered during retreat mining in 1989. No in-mine flows were observed during 1991. Panel 1 W5S Development and retreat mining of this panel oavrted during 1989. The overburden continues to thin to the west; depth of cover averages about 400 feet over panel iWSS (ranging from <200 feet to •