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<br />III. COMMENTS -COMPLIANCE <br />Below are comments on the inspection. The comments include discussion of observations made <br />during the inspection. Comments also describe any enforcement actions taken during the <br />inspection and the facts or evidence supporting the enforcement action. <br />Day Two Inspection (7/10/1997): <br />On the morning of July 10, 1997, Dr. Pendleton and Mr. Mende of MCC inspected the remainder <br />of the Sylvester Gulch surface facilities including the Lower Sylvester Gulch Access Road, Main <br />Ventilation Shafts bench, and the Ventilation Shaft #3 drill pad located to the east of the <br />proposed Electric Borehole. Mr. Boulay and Ms. Johnston inspected the Sylvester Facilities <br />areas, the North Soil Storage area, and the Material Storage Bench. Dr. Pendleton's geotechnical <br />findings from the day two inspection are presented below under "Support Facilities". <br />Support Facilities <br />Lower Sylvester Gulch Access Road -Slope Distortion <br />Pursuant to my suggestion, MCC installed two slot-track tiltme[ers in combination with <br />piezometer installations immediately upslope from the lower Sylvester Gulch Road. The first of <br />these installations has been in place for a month. Offsets have been documented at depths of <br />approximately 15 and 30 feet, roughly corresponding with the existing access road. The <br />approved plan for the widening of the lower Sylvester Gulch road included the excavation of a <br />relatively high cutslope at the location of this tilt-meter. The evidence suggests that excavation <br />of the planned cutslope will initiate an accelerated slope failure at this location. Appropriate <br />methodology exists with which to reinforce this slope prior to excavation of material which <br />currently buttresses the slope. Whether or not these techniques aze adequate to prevent <br />accelerated failure should be analyzed in detail. As an alternative, design consideration could <br />be focused upon the development of a traffic signal controlled single lane access road. <br />The second slot-track tiltmeter was installed the day before my tour of the site. The initial <br />orientation data had been collected, but no comparative subsequent observations had been <br />completed. Based upon my observations of the active landsliding which has characterized this <br />location I anticipate movement similaz to that observed at the first installation. [Nine iterative <br />sensitivity slope stability analyses were conducted for this site. Safety factor results vazied from <br />0.940 to 1.523. It appears the 0.940 may have been accurate.] <br />cutslope South of the Ventilation Shaft Bench -Stability Concern <br />The slope southwest of the main ventilation shafts was being grubbed and excavated. <br />Reconnaissance examination of the large conifers and aspen occupying this slope revealed a high <br />frequency of curved (pistol grip) trunks, suggesting active soil movement. I suspect that this <br />5 <br />