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Susan Burgmaier <br />C -1996 -083 TR -84 PAR <br />06 -Mar -2014 <br />Page 4 of 5 <br />Title could be revised to indicate that this map is for CMWDA No. 3. Other than the fact <br />that this map resides in Volume XI, there is nothing to identify it as such. <br />The map was revised as requested; this item has been addressed. <br />8. MLT 03/06 (New): The second bullet in the Assumptions section of the 15- Oct -2013 <br />Buckhorn analysis states, "revised gob properties were derived from recent laboratory <br />testing on consolidated gob material by ATT Laboratories ". Laboratory test results, <br />particularly those upon which model assumptions are based, should be incorporated <br />into the appropriate geotechnical report(s), as was done by Buckhorn in 2006 and 2007. <br />a) Please expand the TR -85 (and any current or future) stability analysis to include <br />the results of any additional laboratory testing that has been conducted on coal <br />mine waste at the Bowie No. 2 Mine. <br />b) For the native soil, an assumed (� of 34 degrees was used. This value is not <br />consistent with the (i of 30 degrees that was determined by Buckhorn in Mar - <br />2007, based on laboratory testing of on -site materials. Please provide <br />justification for using a revised value for the angle of internal friction of native <br />soil, or revert to using the original value. <br />9. MLT 03/06 (New): The third bullet in the Assumptions section of the 15- Oct -2013 <br />Buckhorn analysis refers to piezometers at Pile #3 that were monitored in June 2013 (no <br />groundwater was observed). The Mar -2007 Buckhorn report approved under TR -45 <br />documents the installation of seven standpipe piezometers in the footprint of <br />CMWDA #3. Based on readings taken in Nov -2007, a phreatic surface was developed for <br />use in the various stability analyses. <br />a) Please expand the discussion of the groundwater phreatic surface to address the <br />condition of each of the piezometers installed in 2007. Which of these <br />piezometers have been disturbed or destroyed? Which, if any, are still in use? <br />What piezometers were utilized in 2013? <br />b) The current analysis fails to consider the effects (if any) of the sub - excavation of <br />soil from the footprint of the pile on the proximity of the phreatic surface. <br />Please expand the analysis to consider Buckhorn's original predicted location of <br />the groundwater phreatic surface (based on the seven standpipe piezometers) <br />and the approved additional excavation of soil material from the footprint of the <br />pile. <br />Volume I <br />1 (14) MLT 01/07: Stover's application cover letter indicates that Volume Xi (CMWDA #3) is <br />being modified to follow the format of Volume IX (CMWDA #2), which will be extremely <br />helpful. Currently the Stability Analysis reports in Volume XI (Table of Contents) are <br />