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• (Page 2) • MINE ID # OR PROSPECTING ID # INSPECTION DATE July 14, 1994 M-80-244 INS PfiCTOR'S INITIALS JAP Phase 1 Toe Dam Embankment Pootprint I inspected the footprint of the heap leach pad, including the recently stripped foundation for the phase 1 toe dam embankment. I was accompanied by John Hardaway of CC~VG and David Kidd of Golder Associates, Inc., consultant to CC~VG. The foundation of the toe dam had been stripped and two inspection trenches had been excavated to examine the bedrock. The majority of the bedrock appears competent. Two shear zones were delineated. One was a narrow (3 feet wide) shear in the northern portion of the footprint near center line of the embankment. This zone is characterized by two discreet several inch wide clay-filled gouges, separated by three feet of intensely jointed, but competent, fractured granodiorite. The fractured granodiorite exhibits thick, black manganese staining. However the rock fragments have not been invasively weathered. This steeply-dipping narrow shear zone immediately adjoins an Aplite dike on its south. This shear zone is damp, having yielded several hundred gallons of water into the trench in the past day. A second shear zone was encountered near the southern extremity of the valley bottom. This zone, unlike the previously encountered structures appears more disseminated. The zone is approximately ten feet wide and characterized by intensely fractured granodiorite. This zone does not contain the discrete clay-lined gouge zones evident in all the others encountered within the valley footprint. The western portion of the toe dam footprint was exposed by excavating the historic tailings from the Carlton Mill. These lens shaped tailings reach a thickness of approximately ten feet, standing without difficulty in a steep cut face. The tails are underlain by three to five feet of soil and subsoil. On the southernmost third it appears the soils are peaty in composition. The tails are also overlain by up to three feet of sediment and transported soil washed out onto the top of the tailings lens. Both of these soil layers appear to be relatively impermeable. A minor flow of approximately 1 gpm is flowing from the exposed tailings lens and ponding in the foot print of the toe dam. The excavated tails have been piled atop the south-central portion of the tailings pond. In discussions with CC~VG's site geologists, i recommended that they complete the inspection trench by connecting the two existing portions. An unexcavated portion had been retained to accommodate equipment movement. This would allow them to exactly define the larger southern shear zone. i then recommended that they observe the footprint while the final scalping is ~ completed by the contractor. it appears that this zone is sufficiently wide to facilitate excavation the contract wan to excavate loose material and replace it with compacted `c structural fill. None he ear ier shear zones have been large enough to facilitately excavation and replacement. Condition of the Heap Leach Footprint I have been impressed by the limited structural disruption encountered in the footprint area, including both the underdrain and the toe dam foundation areas. Based upon the extensive \ ~ land form development within the Arequa Gulch I anticipated more extensive structural control M in the form of more intense and dense shear zones. The footprint shows relatively limited ~ j shear development. The shear zones which have been detected are usually narrow and very ~` discretely bounded by competent bedrock. The impact of the shear does not appear invasive in the adjoining country rock. As a result the majority of the footprint has been excavated ,~ to competent bedrock and will provide a firm foundation for the multilayered liner and the ~ heap leach structure. The shears are usually moist and yield some groundwater flow. While ~ ' it has been a relatively dry winter and spring in Cripple Creek, it does not appear that VJ these shear zones will yield significant flow. The operator and their consultants should ~ b continue to apply the same foundation examination techniques as they progress into the upper elevations of the footprint. Construction of the First Secondary Finger Drain The contractor had excavated the trapezoidal receiving trench for the finger drain to be installed in the first Swale east of the toe dam on the south valley slope. This drainage has evidenced very little flow during excavation of the footprint. We observed some dampness above a clay-filled gouge during several of our earlier inspections. Delay in assembling the crusher intended to produce the underdrain material (12-inch minus), underdrain filter