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progressed since the December 2008 readings. The previous movement in the B -axis of <br />BH05 -05 is interpreted to be due to settlement of the coal refuse. <br />Vibrating Wire Piezometers <br />Five vibrating wire piezometers, designated VWP -01 through VWP -05, were installed in <br />coal refuse at CWDA No. 2 in June 2005. The piezometers were grouted in drilled <br />boreholes as described by BGI (2006). Piezometer locations are presented on the <br />attached Instrumentation Site Plan. Since installation a total of five vibrating wire <br />piezometers have stopped working correctly (VWP -01, VWP -02, VWP -03, VWP -04 and <br />VWP -07). The first two VWP's were damaged and went out of service between June and <br />August 2005. VWP's 03 and 04 had apparent damage and gave spurious readings on <br />June 15, 2011 and were not read after that date. Diagnostic tests on the damaged VWP's <br />indicate that shorts have developed, likely due to damaged cables. Three additional <br />vibrating wire piezometers, designated VWP -06 through VWP -08, were installed at CWDA <br />No. 2 in June 2009 to supplement the remaining piezometers. VWP -07 went out of <br />service between March and June 2011. Completion details of these piezometers are <br />described by BGI (2009). Due to damage to existing vibrating wire piezometers, an <br />additional two VWP's (VWP -9 and VWP -10) were installed on May 18, 2012. Table 1. <br />Below summarizes their locations. During the December 17, 2013 site visit we were able <br />to extract information at installations VWP -05, 06, 08, 09 and 10, which provides good <br />lateral representation of the coal waste in CDWA No. 2. <br />Table 1. Location of VWP's Installed Mav 18, 2012 <br />VWP ID # <br />Northing <br />Easting <br />BH Elev. (FT) <br />VWP Elev. <br />FT <br />VWP -09 <br />18974.15 <br />37495.80 <br />6017.0 <br />5987.0 <br />VWP -10 <br />19096.87 <br />37997.36 <br />6020.3 <br />5990.3 <br />Pore pressures measured to date are presented on the attached Pore Plat figure. Pore <br />pressures at all recording piezometers were constant or decreasing during the 4th <br />quarter of 2013. Those reading indicate generally stable conditions at those plezometer <br />sites. Readings at these piezometers have generally decreased since they were installed. <br />This is a good indication that internal drainage is occurring and that waste material is <br />dewatering due to consolidation and trending towards equilibrium. All measured pore <br />pressures are well below the pore pressures at failure for similar confining pressures for <br />the CU triaxial shear tests that have been conducted as part of the on -going stability <br />evaluation for CDWA No. 2. Tablet. Summarizes the individual pore pressures since <br />installation for the currently active VWP's. <br />2013- REVISED 41" Quarter Monitoring Report PN #05- 126 -GEO <br />March 14, 2014 <br />Page 2 of 7 <br />