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N O'V - 2 2- 9 3 M O N Larry O~hl~r November 22, 1993 P~p~ 2 6 0 2 7 W A T E R W g S T E+ L q N D • • P 0 3 o Approximately 3 - 5 percent of materials placed appear to be greater than the 6' maximum size specified in the construction status report, SRK, October 13, 1983, pg 7. These materials are not being moved to the ouuside or inside sections of the fill, but are being compacted in place. WWL believes that this quantity of oversize will not significantly effect the perfprmanca of the facility. o Densities appear to have been achieved throughout the entir¢¢ lift after cpmpactlpn by the haul truck. This Is being checked with field dan9ity testing. o Materials ere not freezing after removal from the borrow area, transport to the embankment, placement, and compaction. This is confirmed by soil temperature measurements taken by SRK. o Existing Type 2 materials along the upstream face of the main embankment ere being blended into the new fill material with a D-$ cat. • Llner Cover - No liner cover materiel was placed during this period due to erlow and ice on the exppsed VLDPE, Numerous methods are being tried to remove thg snpw end ice including shoveling, adding large quantities of water, pumping of snoVvmelt, and adding Salt. This shoveling created a number of holes in the liner in one: area (Acre 57). These holes were marked by SRK and will be patched by Serrot when they return on site. i • Haul Road Construction - As the northern "loop road' haul route ooUld not be completed, all traffic was routed onto the southern haul road. The road wbs widened in several areas to allpw for two-way truck traffic. Embankment material Was used for the haul road expansion. Haul road materials were not placed on the uncovered VLDPE liner. Borrow Areds - I have regularly inspected both the main pit (embankment rllateriaq and borrow pit (liner cover material) to verify motorists, excavating Conditions and screening operations. All appear to be satisfactory. • Miscellaneous -Tailings deposition is occurring the west impoundment. BMRI is preparing to switch to the east impoundment within several days. The current 'pond' in the west impoundment is several hundred feet away from the main embankment. Deposition on the north side of the west impoundment has eroded the draindge layer at approximately four discharge locations. Therefore, the liner iS exposdd from the main tailings line to the impoundment surface (a digtance of 100 to ' 150 feet). Significant quantlties of oversized materials (over 1'rS-inch size) are nqw in direct contact with the existing geosynthetic liner. Also, tailings are being deposited directly on the liner at the 6esa of these discharge locations li.e. where the current surface of the tailings is located). WWL believes that although these areas are small in comparison to the entire impoundment, they should be corrected (backtilled with suitable liner cover materials).