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Susan Burgmaier 13- Nov -2014 <br />C- 1996 -083 2014 -Q3 CMW Review Page 2 of 2 <br />Referring back to Attachment 1, the second table shows there exists a large gap between the MDD for <br />Sample Nos. 14 -0195 (104.0 pcf) and 14 -0553 (93.5 pcf). As noted in the Division's review of the 2nd <br />Quarter 2014 CMW report, the average MDD reported by Buckhorn Geotech from Jan -2012 to Mar - <br />2014 was 100.0 pcf. We believe that Curve 14 -0195 may present an unreasonably high MDD to which <br />some of the compacted material is being compared, and that this, rather than marginal compactive <br />effort, may be contributing results for % compaction that are borderline. Please consider the <br />development of an additional Moisture- Density curve(s) that will successfully represent materials that <br />lie intermediate to the two curves addressed here. The inclusion of Gradation, Atterberg Limits, and <br />Description (Classification) for any curve so developed would be highly beneficial. <br />Compaction Test results reported for four sample locations on July 25, 2014 referenced Lab No. 14- <br />0553, but the OMC is reported as 14.2% rather than 15.4 %. Please submit a revised report for that <br />date, showing the correct OMC for 14 -0553. <br />With respect to the Instrumentation Report, I have no comments to be addressed. HBET corrected two <br />pore pressure entries that Buckhorn's report misrepresented. The Division should wait until October <br />monitoring results for VWP -06 and VWP -08 are submitted before we determine whether BRL can revert <br />to quarterly monitoring for these two instruments. <br />This concludes my review of the 3rd Quarter 2014 Coal Mine Waste Bank and Instrumentation <br />Monitoring Reports. Please let me know if you have any additional questions. <br />Attachments: <br />1) HBET Moisture - Density Relationship Curves <br />2) Curve No. 14 -019 "Gob #3 Borrow Blend" <br />cc: Dan Hernandez, DRMS <br />