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7 <br />composite translational-rotational slide. There was no obvious evidence of heave or <br />bulging in the pit floor. However, slide debris covered most of the pit floor and would <br />have concealed evidence of the lower end of any failure surface intersecting the pit. <br />A secondary crack and scarp traversed a topographic spur (also referred to as the south <br />peak) at the top of the still-intact portion of the pit slope above the southern half of the <br />slide mass. This spur is visible in the upper left corner of Photo No. 3 and the scarp is <br />shown in Photo Nos. 5 and 6. The secondary scarp indicates a tendency for a <br />progressive failure where repeated movements follow enlargement of the rupture <br />surface. We accessed the top of the pit slope via an access road for closer examination <br />and observed this upper scarp on both December 4 and 5. At the southern side of the <br />spur where the scarp crosses the access road, the scarp exhibited up to about 2 feet of <br />vertical displacement and 1 foot of horizontal separation. On the northern side of the <br />spur, the scarp had about 4 feet of vertical displacement, 2 feet of horizontal separation <br />and the crack walls were nearly vertical and extended to a depth of approximatel20 <br />feet. The angle of the scarp's slippage at the north side of the spur was about 48 degrees <br />in the down-slope direction, as was evident by the offset of the road's safety berm <br />shown in Photo No. 6. Mr. Muller reported that the scarp's offset and separation had <br />increased considerably between December 3 and 4. On December 5, the light snow <br />cover, which fell the previous day, facilitated visual estimates of any additional <br />movement along the scarp. We observed no evidence of additional movement of the <br />scarp between late December 4, 2008, and mid-morning of the December 5, 2008. We <br />also neither saw nor heard any rockfall or raveling in the quarry area during the two <br />visits to view the site. <br />We saw no evidence of water seeps or ice in any part of the pit during the site visit. <br />Mine personnel stated that a small seasonal stream sinks into the ground near the top of <br />the pit wall where the reclamation materials for the "hole" were excavated. This water <br />from this sinking stream reportedly re-emerged at a spring near the mine office, <br />though details of how this was determined were not provided. <br />Site Briefing - December 4 <br />Following the December 4, 2008, site observations, we met at the mine office to discuss <br />the availability of additional information, and the various monitoring and analysis. We <br />reviewed the plans and cross sections prepared for the reclamation plan. Mr. Shafer <br />explained that Transit Mix has logs and possibly rock cores from borings drilled in the <br />past that can be retrieved from files and storage. <br />The drilling contractor, Yenter Companies (Yenter), also performs landslide and <br />unstable rock slope remediation services. Mick Muller, Chief Engineer for Yenter, <br />proposed the following general steps for monitoring and preparation of a remediation <br />plan: