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recommendations or justify it's proposal to use a less stable, steeper pit wall overall slope angle. East Cresson Mine Stability Evaluation The East Cresson mine pit wall stability evaluation, contained as section 2 of Appendix 5 in Volume 3 of the Amendment No. 8 application was prepared as a portion of Amendment No. 7 application in June of 1998. As such it has been previously reviewed and approved by the Division. The Division found the evaluation and report to have been prepared by Adrian Brown Consultants in accordance with the standards of pit wall stability evaluation. CC&VG presents it's permit commitments to pit wall overall slope angles for the East Cresson Mine within table 5-4 on page 49 of the "Project Description" in Volume 1 of the Amendment No. 8 application. In my opinion, table 5-4 faithfully reflects the recommendations of Adrian Brown Consultants. North Cresson Mine Area Slope Stability Evaluation The North Cresson mine pit wall stability evaluation, contained as section 3 of Appendix 5 in Volume 3 of the Amendment No. 8 application was prepared by Adrian Brown Consultants. The North Cresson mine area includes five separate mine pits, designated as "A Area", "B Area", "C Area", "D Area", and the "East Cresson Extension". These mine areas are depicted on figure No. 1 of the report. As such, it appears the first four of the mined areas ("A" through "D") will be completely backfilled beneath the Squaw Gulch Overburden Storage Area. Once backfilled their pit wall stability becomes a mute point to the Division. Prior to their being backfilled, however, the Division is concerned in the unlikely event that mining were to cease and the Division were to assume the responsibility of reclaiming the site. Portions of the highwall of the East Cresson Extension mine pit will probably remain exposed as a portion of the final reclaimed configuration for that mined area. During their data collection and the completion of their evaluation, Adrian Brown Consultants determined that the bedrock geology of the North Cresson mine area differs from that of the Main Cresson and East Cresson mine areas. The North Cresson mine area contains a "schist island", comprised of Precambrian biotite gneisses and schists. These materials are potentially weak, due to foliation and intense deformation. In completing the final recommendations, Adrian Brown Consultants include an accommodation for schist materials that form the northwest and southeast walls of the North Cresson "D" Area. The bench overall slope angle is reduced to 45° to reflect the lower anisotropic strength parallel to the schistosity planes. In addition, rock quality data (RQD) averaging 30% collected from the upper 200 feet of core data in the North Cresson "A" mine area suggest that fractured bedrock in this zone may be unstable. For this reason Adrian Brown Consultants also recommends an overall slope angle of 45° for the uppermost 200 feet of the "A" area mine. The remainder of the North Cresson mine area, including the East Cresson Extension area are found capable of maintaining stable pit walls at an overall slope angle of 60°. Adrian Brown Consultants summarizes it's slope design recommendations for the five North Cresson mine areas, including the East Cresson Extension area, on page 35 of it's report. CC&VG presents it's permit commitments to pit wall overall slope angles for the five North Cresson Mine areas within table 5-6 on page 53 of the "Project Description" in Volume 1 of the Amendment No. 8 application. However, CC&VG overlooked a commitment for slope design of the East Cresson Extension mine area within table 5-6. CC&VG presents it's commitments for slope design on pages 48 and 49 of the "Project Description" of Volume 1 of