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Jai um-Y 1 5. 2008 Page JJ <br />SontliNNest NOIIIIW St <br />IV. <br />IV:IH <br />Figure 38. Schematic Example of Mining in Steeply Dipping Beds Locations of K-Pit <br />Outside the Landslide Area <br />material. Some material might be sufficiently loose in this area that a lower angled cut face <br />should be used (1.311:I V). The decision to flatten the slope will be at the discretion of the TMI <br />engineers depending on local conditions. Blasting may be required for tight interburden below <br />the l'-scam. <br />Once mining has progressed sufficiently eastward and spoils are being piled in previously <br />cut areas spoil, movement may be problematic in areas where the weak Q-floor mudstones are <br />steeply dipping. There is potential for the spoils to 'creep' if saturated. The spoils should be <br />placed a sufficient distance from active mining to prevent spoil creep from interfering with <br />operations. Recommendations for spoil pile design were discussed in Section 4.4. <br />The following four types of monitoring are recommended for the K-Pit area: (I) large- <br />scale downdip hillside movement, (2) local cut-face slope movement, (3) bedding slip, and <br />(4) groundwater elevations. Global movement can be monitored near the bottom of the hillside <br />(K 18- K20) out of the way of mining operations. Survey benchmarks should be installed and <br />monitored in this location to collect data on the magnitude and direction of any large-scale <br />surface movements. Ifthe data indicate significant movement, additional benchmarks should be <br />installed. <br />Local instability of the cut face slope should be monitored for unstable loose blocks and <br />larger-scale face raveling. Because the cut-face will be excavated by dozer, the cut-face is <br />expected to be smooth with few visible blocks. The most effective monitoring of'such faces is <br />visual inspection of loose blocky areas. Unstahlc blocks should be taken dawn as nceded. <br />Characterization borehole 07-(iX6-('('R had inclinometer casing installed to provide <br />information on bedding slip. Borehole 07-GX5-CCR had three piezometers installed to monitor <br />groundwater elevations. <br />Agap ito Associates, Inc.