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N O V- 2 9- 9 3 M O N 1 2 4 6 W A T E R W A S T E~ L A N D P_ 0 3 Larry Oshlsr • November 29, 1993 Pape 2 • Prior to Serrot beginning their patching activities, pre-weld destructive tests wens performed. Pre-weld tests were conducted at the beginning of each day, after env shutdown, and after approximately tour hours of patching. Quality assurance tests results collected 6y SRK were in agreement with quality control test results collected by Serrot. Patching of onanon-passing seam and several tears in the liner are being completed today. • Embankment Construction On the main embankment, the second and third lifts were completed and approximately 25 percent of the fourth lift had been placed and compacted. The top of the fourth lift is approximately two feet above the top of the existing embankment. Construction was slowed due to a change in borrow material characteristics. On the afternoon of November 22, material coming from the pit was deemed unsuitable for embankment constructioh (by SRKI. The unsuitable material was removed from the pit, another area of the pit was blasted, end embankment construction resumed on the morning of November 24. Overall material characteristics have remained the same as outlined in WWL's first weekly report. Densities appear to have been achieved throughout each lift. No frozen materials are being incorporated into the fill. Previous lifts are being scarified before placement of successive lifts. • Liner Cover Several acres of liner cover was placed during this period in addition to completian of the haul road around the north end of the impoundment. SRK instructed the contractor to install additional dreins on the north side of the impoundment to decrease drain spacing. On the morning of November 22, I measured the spacing between two adjacent drains to be 40 feet at the top of the impoundment and approximately 150 feet at the old to ner~v~ liner tie-in (where the new VLDPE was tied into the existing geosynthetic-. After pointing out the spacing to Glenn Buyer of SRK, he informed the contractor, who then added dveral extra drains across the slope to reduce the spacing to approximately 60 feet et t~~ maximum spacing. I believe that if the spacing or lack of drains had not been mentioned to SRK, the contractor would have installed the drainage layer in that area without sufficient dreins. The contrector has been more cognizant of drain spacing since that morning. • Miscellaneous Tailings deposition has been switched to the eastern impoundment. Water accumulating at the base of the newly lined areas from snow melt and precipitation is being pumped across the haul roads and into the existing impoundments to prevent the overnight formation of ice. QUALITY ASSURANCE TESTING AND PROCEDURES WWL has received and reviewed a summary of the field tests conducted up to November 23, on the soils and VLDPE. Actual test results from the field and a summary of laboratory tests have not yet been received, but are in the process of being prepared by BMRI. According to DMG's letter to BMRI (Ken Kluksdahl) dated November 2, 1993, the requirement of a minimum of one gradation per half acre (material already placed) and one gradation per