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Bowie No. 2 notes for site visit June 19, 2013: <br />Bill Bear and I met with Dan Quigley (Buckhorn Geotech) on site today to <br />look at the W. Diversion ditch #1 extension and the area where water was <br />found exiting gob pile #4. <br />Dan was not concerned with the configuration of the new ditch. He agrees <br />that it will be a maintenance issue as opposed to a stability issue and will <br />plan on monitoring it as part of his quarterly inspections. The way the ditch is <br />configured through the coal fines area limits the drainage area above it. So <br />there will be a small amount of sheet flow, and some rilling in the more <br />defined channel areas. Dan does not think there will be any deep seated <br />rotational failures, just the potential for surficial slumping on the face of the <br />upslope. Monitoring will occur after large precipitation events, and <br />maintenance will be performed as needed. Diligent initial maintenance will <br />be key to the success of this ditch. <br />Water exiting gob pile #4 at the toe, or at terrace drains is the natural location <br />where de- watering should occur. Dan inspected a few other locations on the <br />pile that were damp or had obvious signs of being a location where <br />dewatering occurs and expressed confidence the pile is functioning correctly. <br />Old ditches F20 and part of F11 are still in place and connected by C -F3 (see <br />page 2 for structure location). To keep C -F3 operational and clear of debris, <br />rock has been placed around the inlet, and on the slopes around the inlet in <br />an effort to keep the gob from sloughing into and clogging the culvert. Where <br />the culvert outlets, a slight v -ditch will be established to direct flow to F14. <br />Although it was previously reported that rip rap in F20 and F11 will be <br />removed prior to placement of gob in that area, it is now uncertain if that will <br />occur. Since those ditches were plated with well graded rip rap, gob <br />placement over top will not create any stability issues since there are no <br />gaping holes between the rock. <br />We inspected the top of gob pile #2, and the material that had been stacked <br />over the winter continues to dewater and dry out. The operator is trying to <br />keep ditches cut at the bottom of the stacked gob material in order to provide <br />positive drainage away from the pile. Ron Grimlin who is the gob pile <br />foreman understands that keeping the ditches cut is a part of on -going pile <br />maintenance and is working hard to stay on top of the ever changing pile <br />conditions. <br />Pond F is still being cleaned out. Efforts to dewater were somewhat <br />successful, but due to the nature of the material in the pond, it will not <br />completely dewater. The pond dewaters to a point, then a crust forms and <br />what is below the crust does not dewater. The material currently in the pond <br />bottom is very wet and soupy. Therefore, dry gob is being brought down to <br />the pond and mixed with the soupy sediment, then the combined <br />sediment /gob material is being hauled back up to the gob pile. <br />The weather for the next few weeks is hot and dry. Significant progress on <br />placing and compacting gob should continue. <br />I will not be going up to Bowie next week, Jim will be headed up mid -week to <br />do his quarterly inspections. <br />