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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 azea (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 drippets) 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 Stmctures remained essentially unaffected during the period with the exception of the <br />predicted impacts to [he Union Pacific Railroad and Fish Creek as reflected in the data and on [he associated <br />subsidence map. No adverse impacts, i.e. imminent failure of stmcture, 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 neazby surface sites. These sites are shown on the attached Second Half 2005 <br />Subsidence Map. These include alluvia] 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 />A short segment of Fish Creek crosses approximately 160 feet into the zone of anticipated subsidence (based on <br />the subsidence limit line) along the extreme eastern edge of the 19-Right Longwall Panel. Minima] subsidence <br />impacts were anticipated along roughly 500 linear feet of Fish Creek, in this area. Note that during 2006, no <br />significant ponding effects were observed in this azea. Hydrologic monitoring in 2006 did not indicate significant <br />water quality impacts to Fish Creek. Iron concentrations for surface sites SW-14, SW-15, and 305 ranged from <br />350 ug/I to 1300 ug/1. Note that seasonal fluctuations in the concentrations of some analytical parameters (e.g. <br />iron, conductivity, TDS, etc.) do occur at the surface sites. Increases in iron concentration are often related to <br />accumulation and leaching of iron-bearing strata/sediments during spring mnoff. Some elevated iron <br />concentrations may also be related to ponding effects (e.g. increased solids in ponded samples) <br />Foidel Creek: was historically undermined and subsided by TCC's mining of the 9 Rt, 8 Rt, 7 Rt, and to a very <br />limited extent, the 6 Rt panel, and extreme eastem end of panel 12 Rt. Mining in 12 Rt was completed in 2001, <br />and subsequently sealed in September 2001. No significant changes to [he creek channel were noted in 2006. <br />15 <br />