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L LJ ltydrn(ogic Draw bueapefmtan and lmpan Aeo®nnu fo the Permit mdAdjocau Arent "F" Seam 1st West Submain Seale were constructed between the crosscut of the iWSS panel bleeder and the 2W1N panel bleeder (inby crosscut 28). Three rows o[ 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. Pane! 1W1S in this panel during development or retreat. How- ever, flow from panel 1W2S appeared on the floor of the 1st West Submain near the 1W2S seats shortty after secondary mining was completed. During the 4th quarter of 1987 flow was estimated at 3 to 5 gpm. The flow increased to 5.5 gpm and 9.8 gpm during the isi and 2nd quarters of 1988, respectively. Since this time the flow declined steadily, to 1.2 gpm during the 3rd quaver of 1988 and to an unmeasurable amount 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 was oceurring (November 1986 to March 1987). Well 38-H-1 is screened at throe 20- foot intervals midway between the surface and the "F" seam coal. The "F" seam depth of cover 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 slows have been observed since. Water observed in adjacent areas was thought to be coming from panel 1 WZS because it did not appear until retreat mining occurred in panel 1W2S. During 1990, water levels in we]] 38-H-1 remained near pre-mining levels. Thus, data from well 38-H-1 indicate groundwater in the barren member above the rubble zone will not suffer long-term impacts from secondary mining. Wells 38-H-2 and 38-H-3 provided little rueful information (see hydrographs in Appendu I). Subsidence apparently damaged the casings of both wells and connected them with the mine ventila- tion system. In well 38-H-2 the casing was ob- structed at 415 feet bclow the surface. Panel 1 W2S Retreat mining of panel 1W2S was completed in November, 1987. Very little water was encountered Panel 1W3S Development mining in panel 1W3S began in March, 1987. Wet and damp roof areas were encountered from approximately 11 crosscut to 24 crosscu~ These wet areas {roof drippers) produced very little flow 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 associated 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 areas. Panel 1W4S Development mining began in panel 1W4S 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 as large as those present in panel 1W3S and did not produce any measurable flows. No significant flows were encountered during retreat mining in 1989. No in-mine flows were observed during 1991. Panel iW5S Development and retreat mining of this panel oavrred during 1989. The overburden continues to thin to the west; depth of cover averages about 400 feet over panel 1WSS (ranging from <200 Ceet to 9