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Pore pressures at the active VWP locations are anticipated to continue to decrease as <br />drainage occurs. Upward spikes in pore pressure occur in locations where gob is either <br />temporarily stored prior to spreading and compacting or where the pile has received <br />additional coal waste as it is built upward. In our analysis we look at those spikes and <br />monitor the trend in reading after the spikes. In all cases, the VWP's have recorded <br />declining pore pressures following those spikes. Triaxial testing, performed in 2008 and <br />again in 2013 on gob samples, indicates a range of pore pressures at shear failure from <br />37.8 to 38.9 psi with an average of approximately 38.0 psi. Therefore, a pore pressure in <br />excess of 35.0 psi at any VWP location would be a concern and would require immediate <br />attention. To date, the highest recorded pore pressure has been 20.9 psi at VWP -07 (no <br />longer active) on December 21, 2009. Among active VWP's the highest pressure has <br />been 15.0 psi at VWP -08, also reported in our December 21, 2009 instrumentation <br />monitoring report (4t' Quarter, 2009). <br />In any event, on -going monitoring of all piezometers is recommended to monitor pore <br />pressure responses to the on -going refuse placement. Otherwise, the measured pore <br />pressures are consistent with the revised stability evaluation for the coal refuse <br />performed by BGI (2008). <br />Site Visit Observations <br />During my site visit on December 17, 2013 with Mr. Gary Harding (Bowie Resources) and <br />Ms. Tamme Bishop of J.E. Stover & Associates, no gob stockpiling or processing was <br />being performed at CWDA No. 2. It is our understanding that, due to winter conditions, <br />Pile #2 will not be used until spring. Ms. Bishop and I walked the perimeter of Pile #2, <br />including the drainage ditch upslope of the pile, and I did not observe any surface <br />failures in either compacted or uncompacted gob. The air temperature was approximately <br />40 degrees F in sunny conditions and surface drainage from snow melt was observed in <br />several of the drainage culverts and ditches that serve Pile No. 2. <br />In general, the grading and compaction of CWDA No. 2 appears to be progressing well <br />and significant work has been done since our last site visit in September 2013, as <br />indicated by our weekly compaction testing and observation reports. CDWA Pile No. 2 <br />appears to be stable and in good condition for winter storage until processing operations <br />begin again in spring 2014. <br />2013- REVISED 411 Quarter Monitoring Report PN #05- 126 -GEO <br />March 14, 2014 <br />Page 4 of 7 <br />