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Lateral extensions of this scarp have extended tension cracks further to the north and south. <br />This movement also resulted in the rubblization of an additional portion of the southern mine <br />wall, which is the most obvious and visual aspect of the new rockslide. <br />Monitoring data indicate that the slide mass was moving prior to the initial date of <br />monitoring on September 9. 2009, and was in a pre-failure mode of movement when workers <br />were on the landslide installing the prisms. It was this potential scenario that led us to <br />discourage the installation of prisms in our January 7, 2009 memo. The data set that was <br />submitted to DRMS and forwarded to the CGS is incomplete, and only represents vertical <br />displacement (not lateral displacement) for a period of approximately 20 days, and for only the <br />southern portion of the rockslide complex. We have not received the movement data for the <br />entire array of prisms shown in the digital file: Pikeview Monitors 2.jpg (Figure 3 top). <br />13 24 <br /> <br />Figure 3. Top image of quarry wall after December 2008 rockslide forwarded to DRMS and CGS from <br />mine operator showing location of prism array. Accompanying graphical data did not included <br />movement data from prisms 20 through 30 in the northern block. Bottom image was taken during <br />our September 2009 site visit after portion of southern block failed (shown by red shading).