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0 <br />upslope of the failure area. The weathered claystone materials were encountered from 7 to 10 feet beneath the ground <br />surface (bgs) in the slide area and at a depth of 2 feet bgs in TH -11. The weathered claystone materials were nil to <br />slightly sandy, moderately to highly plastic, blocky and highly fractured, moist to wet and gray to black in color. <br />Claystone bedrock was encountered below the weathered claystone materials in the test holes drilled in the failed area <br />at depths ranging from 12 to 16 feet bgs; whereas the competent bedrock was encountered in TH -I I at a depth of 5 feet <br />bgs. The claystone bedrock materials were nil to slightly sandy, moderately to highly plastic, hard to very hard, dry to <br />slightly moist and gray to dark gray in color. <br />Groundwater seepage was not encountered in the test holes at the time of drilling; however groundwater was <br />encountered in TH -12, TH -13 and TH -14 when measured 1 day after the drilling was completed. Groundwater <br />seepage was actually flowing out the top of the drill holes at the ground surface in test holes TH -13 and TH -14 and at a <br />depth of 10 feet bgs in TH -12. TH -11 was still dry when measured on July 2, 10 10. Temporary slotted and solid PVC <br />casing was installed in the test holes so that the groundwater levels can be monitored. <br />Shrub Plot Landslide -Site Observations and Subsurface Investigations: Based on our observations made in 2010, <br />it appears that the slope failure that was previously observed below and to the northwest of the Shrub Plot had <br />increased in length to the west- southwest; however, the height and location of the head scarp appeared similar to <br />previously observed head scarps. It should be noted that the client has regraded this area several times since our initial <br />observations in 2008. At the time of our site visits in 2010 a considerable amount of water was daylighting/flowing out <br />of the failed materials situated downslope of the head scarp. In addition, a new tension crack was observed upslope of <br />the previous head scarp location and this tension crack appears to run in a southwest to west direction towards the Pond <br />016A slope failure. <br />NWCC observed the excavation of four test pits (Test Pit SP -1 through Test Pit SPA) in this slope failure on <br />September 18, 2008. The test pits were excavated with a trackhoe provided by Seneca and at locations determined in <br />the field by NWCC. NWCC also advanced two test holes (TH -15 and TH -l6) within the failed area on July 1, 2010 <br />with a track - mounted drill rig using 4 -inch diameter continuous flight augers. The test pit and hole locations are <br />provided in Figure #1- Appendix B. <br />The subsurface conditions encountered in the test pits and holes were variable and generally consisted of man -made fill <br />materials that extended to the maximum depth investigated, 19 feet. The fill materials generally consisted of clays and <br />topsoil materials with bedrock fragments. The fill materials were typically very soft to loose, moderately plastic, dry to <br />wet and brown in color. Clay fill materials that were considerably stiffer and contained more sandstone and coal <br />fragments were encountered in Test Pit SPA at a depth of 7 to 13 feet beneath the existing ground surface. It appears <br />that the majority of the fill materials encountered in the test pits were placed during reclamation. The deeper fill <br />materials encountered in Test Pit SPA appear to consist of compacted on -site materials associated with a truck access <br />ramp heading into the previous mine area. Graphic logs of the test holes are presented in Figure 92- Appendix B. The <br />Legend and Notes associated with the test holes are presented in Figure #4- Appendix B and graphic logs of the test pits <br />along with the associated Legend and Notes are presented in Figure #5- Appendix B. <br />Groundwater seepage was encountered in Test Pit SP -I at a depth of 12 feet beneath the existing ground surface at the <br />time of excavation and in Test Hole TH -16 at a depth of 18 feet bgs when measured l day after the drilling was <br />completed. The remaining test pits and holes were dry. <br />Job Number: 09 -8099 NWCC, Inc. Page 3 <br />