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l~ J n U Hydrologic Dora huopaadon and rmpaa Avemnatt fa the Pamir and Adjacau Anar 750 feet at the southern panel end). Coal height also thins to the west Mining wnditions were similar to those in panel 1W4S. Roof drippers and wet areas occurred, but no significant inflows were encountered. Panel 2W1N This panel waz developed and completely reveat mined during 1990. The panel consisted of 18 crosscuts driven west off of Panel 1W1N. After the panel was retreat mined, a small wet area developed on the floor in the 1st West Submain adjacent to the panel. However, pumping waz unnecessary and the wet area dried up. During 1991, no in-mine [lows were observed in this area. Panel 1 WfiS Mining o[ this panel began during 1989. Panel 1W6S is under an average of about 350 feet of overburden. Due to the trend of decreazing cover and thinning coal with westward expansion, this panel was the last panel to the west driven off the 1st West Submain. Hydrologic conditions in this panel were similar to the other panels off the 1st West Submain. The panel was mostly dry. Howev- er, afew very small localized damp roof areas or roof drips have occurred. Panel 1W6S was completely retreat mined during 1990. No new wet areas were encountered during retreat mining. No in-mine flows were observeA during 1991. Panel 1W1N This panel was developed and retreat mined during 1990. The panel consisted of 12 crosscuu. Roof and overburden conditions over the last five crosscuts in this panel were not favorable for extensive mining. Overburden thickness ranges from 500 feet to 800 feet In addition, a drainage overlays these five crosscuts. Thus, the roof in this area was highly fractured and unstable. Berettse retreat mining could not safely occur under these conditions, the pillars were leh in place. Although water was present in the panel during mining, it was very limited. Roof drippers were present in the Iazt five crosscuts for the first mont4 after development Thereafter, the roof remained damp. No in-mine flows were observed from this panel during 1991. 10 Roof and overburden conditions over most of this panel were similar to those is Panel 1 W 1N. Over- burden thickmess ranges from 200 fee[ to 750 feet In addition, a drainage overlays most of this panel. In particular, the roof over crosscuts one through 12 was highly fractured and unstable. Because the entire panel could not be reueat mined safely, some pillars were leh in place. At one point, a roof fall buried a ramcar. This ramcar waz parked and unoccupied at the time of the fall. However, all attempts to safely recover the equipment failed and the ramcar was left buried. Limited water waz present in this panel. During development, roof drippers appeared in the south half of the crosscuts, This area continued to be wet through retreat mining. However, at no time waz pow from these drippers meazurable. No in-mine [lows were observed during water year 1991. 1st East Submain The 1st East Submain was retreat mined and sealed during the first half of 1989. Poor roof conditions (fractures, water, and weak rock materi- al) were the major reasons for retreat mining this Submain section. Although increased flows may occur following subsidence, they are not expected to be significant. No Oows have developed to date. An alternative access Submain to coal in the eaztern portion of Federal Lease C-1362 fr planned. Placement of this Submain would be further to the south under higher overburden and further from the fracture zones associated with the branches of Sylvester Gulch. However, due to ongoing development o[ the "B" seam, this Sub- main is unlikely to be driven Cor several years. 1 Northwest Submain MCC began developing the 1 Northwest Submain during 1990. This Submain strikes out from the