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Larry Oehler November 22, 1993 PeQe 2 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, 1993, pg 7. These materials are not being moved to the outside or inside sections of the fill, but are being compacted in place. WWL believes that this quantity of oversize will not significantly affect the performance of the facility. o Densities appear to have been achieved throughout the entire lift after compaction by the haul truck. This is being checked with field density testing. o Materials are 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 are ' being blended into the new fill material with a D-8 cat. • Liner Cover - No liner cover material was placed during this period due to snow and ice ' on the exposed VLDPE. Numerous methods are being tried to remove the snow and ice including shoveling, adding large quantities of water, pumping of snowmelt, 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. • Haul Road Construction - As the northern "loop road" haul route <:ould not be completed, all traffic was routed onto the southern haul road. The road •Nas widened in several areas to allow 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 Areas - I have regularly inspected both the main pit (embankment material) and borrow pit (liner cover material) to verify materials, 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 drainage layer at approximately four discharge locations. Therefore, the liner is exposed from the main tailings line to the impoundment surface (a distance of 100 to 150 feet). Significant quantities of oversized materials lover 1 %:-inch size) are r.ow in direct contact with the existing geosynthetic liner. Also, tailings are being depcsited directly on the liner at the base of these discharge locations (i.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 (backfilled with suitable liner cover materials).