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ST -02 Slide Repair <br />At the time of our inspection, the ST -02 slide repair was completed and we don't have a <br />comparison of designed and as -built construction, or if the recommendations in the Ground <br />Engineering report were complied with. Portions of the final slope at ST -02 appears to be slightly <br />oversteepened from the design 2:1 slope. Unfortunately, we didn't have a brunton or inclinometer to <br />actually measure the slope. However, the reconstructed slope appeared stable at the time of our <br />inspection. <br />HR -1 Slide Repair <br />At the time of our inspection, the HR -1 slump areas were reconstructed but the slopes were <br />only roughed in and no preparation for revegetation was completed yet. The roughed -in slope <br />appeared to be slightly oversteepened and small slumps and earth flows were partially blocking the <br />drainage blanket interceptor trench ( ?) below. Tension cracks were also noted near the crest of the <br />rough -in slope of the east slump area and below the lateral ditch. <br />1. In the Barr report, Page 1, 1.1 Background section, it states that "Mountain Coal <br />Company began construction of the RPEE in the summer of 2010 and was completed in <br />early 2012." While it may be a misunderstanding on our part, at the time of our <br />inspection, the RPEE is far from completed. <br />2. Our understanding of the Barr report is that there are two stability analyses. The first for <br />the modeled designed slope, and the second for the as- built. The analyses shows that <br />there was a decrease in safety factors from the modeled design shown in Table 3 on <br />page 7, compared to the as -built analyses shown in Table 5 on Page 10. That as -built <br />analyses shows that a saturated reconstructed slope under seismic conditions could fail <br />(i.e., below unity, or a safety factor below 1). We are unsure whether this is permissible <br />according to DRMS rules and regulations. <br />3. We found no discussion in the Barr report on what is considered the designed final slope <br />grade for the reconstructed slope below the haul road at the east and west slump areas. <br />As measured with a protractor the HR -1 finished grade ranged from 27 (2:1) to 35 (1 <br />'/2:1) from Figure 5 details and the stability analyses geometry in the Barr report (though <br />the stability analyses did not appear to be scaled at exactly 1(H):1 (V). The actual design <br />grade needs to be explicitly stated. <br />4. The carbonaceous shale discussed in the report is not shown in the Figure 5 details. <br />5. At the time of our inspection (April 10, 2012) the HR -1 reconstructed slope has a gravel <br />blanket that simply daylights into a roughed -in ditch and runs laterally, eastward, to <br />another ditch. Small earth slumps were filling the ditch and covering the filtration - blanket <br />gravel. It is unclear whether this open ditch is part of the not - completed drainage blanket <br />