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exhibiting the highest flow in 2013, are almost dry. The majority of the drippers seen in 2013 and 2014, had <br />dried up by 2015. <br />Wolf Creek Seam: Inflow notes were made by Twentymile consultant and geologist, Rocky Thompson during <br />2018. A summary of his observations follows: <br />Overall there were few long term inflow sites, one floor spring remains in 8 EAST with 0.5 GPM inflow <br />continuing for more than several months, possibly still flowing from fractures in floor. The roof drippers tend to <br />dry out within less than 3,000 feet from active CM face, often in less than three months. <br />A few roof drippers associated with 15' to 25' deep test holes have been noted but are generally dry within three <br />months. The majorities of roof drippers are less than 0.05 gpm and must be calculated for a larger square area <br />with several often found in one or more entries at the same time. Long term the roof drippers seldom have <br />significant contribution to inflow rates. <br />Water quality samples were collected and sent to ACZ Lab for analyses. Test results for water samples <br />Are posted on the AutoCAD base map. <br />10 EAST: 10 East had more roof drippers on development than 9 East. The 10 East roof drippers per the <br />mapping would average about 1 GPM per 1,000 feet of 3 -entry gate road. I realize this may seem low - well <br />documented that a small (1 16 gpm) dripper can cause a wet spot in the roadway resulting in a big hole full of <br />mud. <br />9 EAST: The 9 East roof drippers per the mapping would average about 1 GPM per 1,500 feet of 3 -entry gate <br />road, less than observed in 10 East. All active drippers are mostly dry now, 9 East from XC 74+00 into XC <br />144+00, a distance of 7,000 feet. <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 may be performed in 2020, which would require expenditures for flow meters at key locations. <br />4.0 SUBSIDENCE IMPACTS <br />Historical subsidence information can be found in previous Annual Hydrology Reports. <br />Wolf Creek Seam Mining: <br />In 2018, TC hired the consultant SubTerra, Inc. to perform subsidence evaluations for the mine site. Their reports <br />and maps were provided to Tabetha Lynch of DRMS via emails from Michael Berdine of TC, on March 29, <br />2017. Excerpts from their reports follow in the conclusion section below. <br />17 <br />