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along the Sylvester Gulch Access Road, and Section F-F' is through the large cut slope north of the proposed substation. Golder Associates performed stability analyses for all eight locations based on soil and rock strength pazameters consistent with the available data. Summary tables of this information were included in MCC's previous response as well. In reviewing the submitted geotechnical data and stability analyses, the Division responded that the lack of site specific strength parameters and the omission of sensitivity analyses (e.g., back calculation of soil strength properties based on assumed safety factors of 1.0) for cut slopes within mapped slide zones made the current slope stability analyses inadequate to fully address prevailing slope stability concerns. The Division also disagreed with the use of preemptively conservative strength pazameters based on the historic data, which may or may not be representative of actual, site-specific conditions. Finally, the Division has stated that regazdless of analytical results, localized slope failures at these areas during construction are probable, and it is incumbent on MCC to proceed cautiously. The Division has also recommended that MCC use constmction techniques that will not destabilize slopes under constmction, make frequent observations of field conditions and activities, and have contingency plans in place to redesign facilities and mitigate slope failures in response to observed conditions. MCC agrees that a conservative approach for cut slopes in potentially unstable areas is justified. Based on MCC's conversations with the Division, we believe the Division agrees that the selection of these cut slopes as the critical locations for site specific analysis is appropriate. The scope of MCC's proposed program mirrors the Divisions stated concerns, and focuses on cut slopes in the critical aeeas defined above. For these aeeas, MCC intends to conduct full scale constmction • activities only after additional site-specific soils data is collected and analyzed, and designs are verified and/or modified. Field observations, and close control of the construction process will also be implemented. As a first, proactive step toward obtaining additional site specific data for critical locations, MCC conducted a drilling program in early April 1997 for the lower Sylvester Gulch road and substation (MR 210). Twelve holes were planned, however, due to weather conditions only 8 sites could be accessed. Samples for strength analysis were obtained and are currently undergoing laboratory analysis. Within these eight locations four piezometers and one slot track inclinometer were also installed. Initial readings on these installations were done the week of April 7th. Additional readings aze scheduled at two week intervals until construction activities destroy the installations. Laboratory results, field measurements, and updated stability analyses are pending, and will be forwarded to the Division for review once completed. The four drilling locations not accessed in eazly April, and additional locations above the shaft site and along the upper portion of the water tank road will be investigated as weather and access conditions permit. Constmction of drill roads to these locations will be required, however, soil cuts will be minimized to extent possible. Water control and "top down" construction techniques described in the next section will be employed to avoid potential destabilization of affected slopes. Additionally, sensitivity analyses (e.g., back calculations) as requested by the Division, for Sections A-A', D-D', and F-F' have been prepazed and are detailed below.