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P4INE ID # OR PROSPECTING ID#: M-1973-021 PAGE: 3 :CNSPECTION DATE: 6-26-01 INSPECTOR'S INITIALS: ACS :>igns of bulk instability. The mitigation and continued quarrying of the east wall of the central quarry has resulted in the stabilization of the pit wall failure that occurred in the early 1990s. The only potentially adverse affect of the east highwall mitigation is a slight lowering of the crest of the east side of the quarry and potentially :_ncreased visibility of the quarry from populated areas to the east. A walking inspection was conducted on one of the lower benches of the central quarry. Most of the depth of the central quarry daylights to t:he north, so the highwalls on the east, west and south :;ides were zivailable for inspection. The quarry is developed primarily in hard, competent gneiss that is jointed, foliated, and faulted. Near surface rock is weathered, but the weathered material quickly grades into i:resh, competent rock at depth. Visible ,ground water seepage on the cTuarry walls was minimal at the time of this inspection. The most concentrated area of seepage emerged below a draw that enters the c;uarry area from the west. Joints and foliation dipping into the pit were observed, particularly on the east (west facing) side, but these joints appeared to be tight and relatively discontinuous (i.e., intact Pock appears to heal the joints at somewhat regular intervals). Areas of small scale sloughing off benches were observed. These small i'ailures are controlled by fractures dipping into the pit or by the intersection of joints resulting in V-shaped rock wedges dipping into t:he pit. The dip angle of these joint sets appears to be too steep to result in bulk failure of the quarry walls. This observation agrees with the data and conclusions reported in the geotechnical addenda to t:he annual reclamation reports. ]:n summary, qualitative observations of the benches and highwalls in t:he central quarry were recorded. All observations correlate~9 with the creotechnical reports submitted each year by the Operator. No indications of bulk slope instability were observed. In accordance with the approved quarry plan, all perimeter blasts that cre~ste final, F~ermanent faces for the quarry are controlled blasts. Controlled r~lasting techniques preserve intact rock bridges within joint sets to minimize raveling from final quarry walls. Half cast blasting holes were observed where pre-split controlled blasting techniques were employed along the final central quarry perimeters. 'T'here are three large product stockpiles located just north of the central quarry and back against the east facing hill slope. See attached photos for additional information on these piles. Backfilled benches along the north (south facing) wall of the north