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Table 2. Su mary of Active VWP Pore Pressures <br />VWP ID <br /># <br />Initial Pore <br />Pressure <br />(psi) <br />12/17/13 <br />Pore Pressure <br />(psi) <br />Difference <br />(psi) <br />Comments <br />VWP -05 <br />6.8 <br />2.5 <br />-4.3 <br />Steady decline <br />VWP -06 <br />11.3 <br />15.2 <br />+3.9 <br />Peak of 16.2 (3/14/13 <br />VWP -08 <br />12.2 <br />13.4 <br />+1.2 <br />Peak of 15.0 (12/21/09 <br />VWP -09 <br />1.5 <br />1.7 <br />+0.2 <br />Stead <br />VWP -10 <br />0.6 <br />0.7 <br />+0.1 <br />Stead <br />Discussion of Individual Active VWP's <br />VWP -05: Installed on August 3, 2005, VWP is installed near the toe of the CDWA #2 <br />pile adjacent to the access road /bench. This VWP monitoring indicated a decline in pore <br />pressure from an initial value of 6.8 psi to the March 2006 reading of 3.5 psi. The <br />readings at VWP -05 have remained generally stable with a range from 3.6 to 2.1 psi <br />since March of 2006. <br />VWP -06: Installed on June 5, 2009, VWP had an initial pressure of 11.3 psi. We <br />recorded a spike of 16.2 psi in our March 14, 2013 monitoring report which is consistent <br />with the additional storage of coal waste near the VWP -06 site at that time. Since that <br />time, VWP -06 has shown a steady decline in pore pressures to its most recent reading of <br />15.0 psi. This indicates that the upper Pile #2 slope near VWP -06 is experiencing <br />anticipated dewatering. Pore pressures are expected to increase slightly as additional coal <br />waste is added to the slope near the VWP -06 site, but again, we are looking for a <br />downward trend in pressures as the pile dewaters and reaches equilibrium. <br />VWP -08: Also installed on June 5, 2009, VWP -08 had an initial pressure reading of 12.2 <br />psi and a peak of 15.0 as reported on December 21, 2009. That peak, as with VWP -06, <br />was coincident with the addition of coal waste near the VWP -08 site: By March 2010 the <br />peak pore pressures at VWP -08 had dropped and have remained steady with a range of <br />13.9 to 13.0 psi. <br />VWP -09: This VWP was installed on May 18, 2012 to provide an additional analysis point <br />near the toe of CDWA #2. After an initial reading of 1.5 psi, VWP -09 has remained <br />generally stable with the latest reading at 1.7 psi. These readings are indicative of a <br />generally stable slope with consistent pore pressure indicating mostly complete <br />dewatering. The area around VWP -09 is generally in its final grading state and over time <br />the pore pressures are expected to remain constant or slightly decrease as the area near <br />VWP -09 reaches its equilibrium state. <br />VWP -10: Also installed on May 18, 2012, VWP -10 had an initial reading of 0.6 psi and a <br />current reading of 0.7 psi. Like VWP -09, the area surrounding VWP -10 is not expected to <br />receive any additional gob and is awaiting final reclamation. Pore pressures are expected <br />to stabilize following that reclamation at or near their current readings. <br />2013- REVISED 41' Quarter Monitoring Report PN #05- 126 -GEO <br />March 14, 2014 <br />Page 3 of 7 <br />