Laserfiche WebLink
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 l ORT well shaft during 2011. <br />Northern Mining District (NMD): At the time of the 2010 inflow study, the mine operation had completed the 23 <br />Rt panel. The primary sources of water came from the two most recent shafts in the 6MN area, and two fault <br />crossings. Total inflow was estimated to be on the order of 80 gpm. Inflows continued in the Northeast <br />Submains, although there appears to be a continued decrease in ceiling dripping. The highest inflows were about <br />20 gpm for the new 6MN shaft, and about 15 gpm from a floor sump at inflow site 8 (IF8) with a conductivity of <br />2270 (Trout Creek Water). This may have been impacted by the addition of roof drip collection to the sump <br />system. The next highest inflow was at raise bore area (IF 38 and IF 37), which was on the order of 10 -gpm <br />(down from an estimated 20 gpm in 2005), Field conductivity measurements were about 1500 umhos /cm. This <br />site is a blend of Wadge and Twentymile Sandstone water. Inflow at the remaining sites (primarily roof drippers) <br />were either dry or significantly lower, often less than a gallon per minute. <br />New Western Mining District (WMD): The 2011 inspection along the newly completed 17LT and 18LT gate <br />roads indicated estimated inflows of 15 to 20 gpm. The majority of sites were modest roof drippers, with sites 55 <br />and 57 exhibiting the highest flows, both on the order of 1 to 2 gpm. The majority of the drippers seen in 2010, <br />had dried up. <br />3.9 Water Balance <br />In early 2009, TC conducted a water balance study to better access water use and allocations for mine operations, <br />as well as mine dewatering. A flow chart was provided in the 2009 AHR, illustrating water movement for the <br />mine in early 2009. Note that there have been some changes in flow patterns since this study. Another mine <br />water balance is anticipated to be performed in 2012, which would be reflected in the 2012 AHR. <br />4.0 SUBSIDENCE IMPACTS <br />Fish Creek: Historically, hydrologic monitoring of potential subsidence impacts from the earlier 17 and 18 - <br />Right Panels utilizes four alluvial wells and four nearby surface sites. These sites are shown on the attached First <br />Half 2008 Subsidence Map. These include alluvial well AVF -14 and associated surface site SW -14 (upstream of <br />17 -Right subsidence zone). Also utilized are alluvial well 008-AU3 and associated surface Site 305 (downstream <br />of 17 -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 /early- October of 2004. The creek bed flow path subsequently reestablished itself. <br />A portion of Fish Creek was last subsided in 2006. In that year, a short segment of Fish Creek crossed <br />approximately 160 feet into the zone of anticipated subsidence (based on the subsidence limit line) along the <br />16 <br />