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(Page 2) MINE ID f OR PROSPECTING ID ~ H-80-246 INSPECTION DATE 30-24-94 INSPECTOR'S INITIALS ACS OBSERVATIONS A monitoring inspection of the Phase 1 leach pad construction was conducted. Several new geomembrane installation contractors have been brought on to the Bite. One or more of the new geomembrane crews use wedge welders that leave larger overlaps both top and bottom. Ae a result, when a patch ie applied to a wedge welded seam, the installer moat cut away the top overlap where the patch extrusion weld intersects the wedge. weld. Thies is done to eliminate a potential leakage pathway beneath the overlap. Verification of elimination of any leakage pathway ie through vacuum testing. The Division has no problem with the cutting away of the overlap as long as the contractor does not cut into the hot shoe weld. The installation locations for vibrating wire piezometere P4 and PS were inspected. The piezometere are et ill awaiting field calibration prior to backfilling. Piezometer location P4 has been completely surrounded by drain cover fill, but a hole in the fill has been left where the piezometer is located. The toe of the current extent of the drain cover fill on the south aide of the pad was inspected. A number of oversize rocks were observed and removed from the fill, including one boulder. The operator moat ensure that the oversize removal crews have adequate light during second shift operat lone eo that oversize ie completely eliminated from the drain cover flll. Oversize elimination ie particularly critical in the lowest one foot of the fill. eackfilling of the lower anchor trench at its upper end was observed. Backfilling of the anchor trenches le accomplished using soil liner fill. The trench fill is placed in thin lifts by hand shoveling and compacted using a hand operated smooth plate vibratory compactor. The operator must aeeure that the smooth VLDPE installed above the lower anchor trench is pulled back sufficiently to avoid damage during backfilling operations in the trench.' The operator must further aeeure that wedge and extrusion welds are carried at least one foot into the lower anchor trench, and that, at a minimum, the texture VLDPE extends all the way across the bottom of the anchor trench and starts up the back Bide in order to aeeure a good anchor. Anchoring assurance will require welding on a tag of additional VLDPE in several of the locations observed. Installation of the middle, or second finger drain on the north Bide of the pad was inspected. The finger drain trench is being installed in bedrock. The trench cross-section was measured to be 2.5• deep x 5' wide which exceeds the cross-sectional area in the approved drawings. Underdrain fill, consisting of durable granodiorite, was being placed in the lower end of the finger drain trench. A small excavator with a hammer attachment was breaking up oversize in the underdrain fill. Geomembrane deployment on the face of the toe berm was inspected. A number of pressure testa of wedge welds were audited. Installation and testing was proceeding in accordance with the approved epecif icatione. I left the Bite at approximately 3:00 p.m. I b E Contact Addreee: NAME John Hardaway OPERATOR Crinole Creek and Victor Gold Co. STREET P.O. Box 191 CITY/STATE/ZIP Victor, CO 80860 cc: Berhan Keffelew Carl Hount CE ~ BL ~ FS ^ HW ~ HMWMD (CH) ~ SE ~ WQCD (CH) ~ OTHER