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The WMD was closed in 1996 at that time inflows were 52 gpm. Note that water elevations for the WMD were <br />• monitored periodically at the Fish Creek Borehole. Our best estimate is that inflows for the WMD are still on the <br />order of 50 gpm. <br />Longwall mining was completed in the EMD by early-January 2001. Production from the NMD, 12 Rt Longwall <br />Panel, was underway by late January 2001. The EMD was petmanently sealed in October 2001 removing all <br />access to the 6 Rt and 7 Rt gate roads. Thus, no measurements are available in this area for 2006. Historical data <br />is available in previous AHRs. The last flows measured for 2000 showed seasonal variations, with an average <br />annual flow of approximately 65 gpm. The EMD was monitored periodically at the lORT well shaft during 2006. <br />Norther Mining District (NMD): At the time of the 2006 inflow study, the mine operation was nearing the end of <br />the 19 Rt panel. During 2006, the main sources of water came from the two most recent shafts in the 6MN area, <br />and [wo fault crossings. To[al inflow is estimated to be on the order of 90 gpm. Inflows continued in the <br />Northeast Submains, akhough there appears to be a continued decrease in ceiling dripping. The highest inflows <br />were about 25 gpm for the new 6MN shaft, and about 15-20 gpm from a floor sump at inflow site 8 (IF8) with a <br />conductivity of 2268 (Trout Creek Water). This may have been impacted by the addition of roof drip collection <br />to the sump system. The next highest inflow was at raise bore area (IF 38 and IF 37), which was also on the order <br />of 15 gpm (down from an estimated 20 gpm in 2005), Field conductivity measurements were about 1500 <br />umhos/cm. This site is a blend of Wadge and Twentymile Sandstone water. Inflow at the remaining sites <br />(primarily roof drippers) were significantly lower, often less than a gallon per minute. <br />• 4.0 SUBSIDENCE IMPACTS <br />During the second-half of 2006, water quality data was collected from established sites along Fish Creek in areas <br />underlain by gate-roads or longwall panels, as well as from representative downstream sites located away from <br />the subsidence area. Structures remained essentially unaffected during the period with the exception of the <br />predicted impacts to the Union Pacific Railroad and Fish Creek as reflected in the data and on the associated <br />subsidence map. No adverse impacts, i.e. imminent failure of structure, were evident. (See Second Half 2006 <br />Subsidence Survey Report). <br />Fish Creek: Hydrologic monitoring of potential subsidence impacts from the 17 and 18 -Right Panels utilizes <br />four alluvial wells and four nearby surface sites. These sites are shown on the attached Second Half 2005 <br />Subsidence Map. These include alluvial well AVF-14 and associated surface site SW-14 (upstream of 17-Right <br />subsidence zone). Also utilized are alluvial well 008-AU3 and associated surface Site 305 (downstream of 17- <br />Right subsidence zone). Note that sites 305 and 008-AU3, were designated under TR03-42 as downstream <br />subsidence monitoring sites. <br />Alluvial well AVF-15 and associated surface site SW-15 are located between the two sets of upstream and <br />downstream sites, presently within a ponded subsidence zone. Localized ponding occurred in this area in <br />• September/eazly-October of 2004, and has persisted through the second half of 2006. <br />14 <br />