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' A couple of outboard bench edge failures (limited to individual benches)occurred in late <br /> 1996 and early 1997 at 80 ft interim highwalls where south dipping foliation joints <br /> daylighted. Current mining of 40 ft highwalls progressing in a westerly direction <br /> ' improved interim stability conditions. <br /> Due to the geometry of the current mining configuration with respect to the filial <br /> proposed mine buildout, none of the 1997 highwalls in the North Quarry are expected to <br /> be fully developed final quarry highwalls. About 200 linear ft of two 40 ft to 60 ft <br /> highwalls near the north-central part of the North Quarry between approximately El. <br /> ' 6,760 ft and E1.6,860 ft are approaching final highwail locations near the haul road that <br /> runs inside the Limits of Mining and these will be evaluated during 1998. Because no <br /> final highwalls were established in the North Quarry in 1997, detailed geotechnical <br /> ' evaluations were not necessary and were not performed. Observations were made, <br /> however, by both Haley & Aldrich and CAMAS, to assess highwall stability and safety, <br /> respectively. <br /> 1 <br /> 1 ' <br /> ' 5 G:IPROJEr-TS\20200=2\97ANNRPT.WPF <br />