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Project Update <br />Page 2 <br />depth to the rock contact but a thick impermeable clay layer was found with groundwater <br />flowing on top. This flow was feasible to intercept and divert around the tailings <br />impoundment. <br />Overburden material was removed from the area down to the impermeable clay layer. A <br />ditch was then excavated into the clay layer to intercept any water flowing along the <br />overburden -clay layer contact. This ditch was lined with 40 mil PVC and in areas with <br />flowing water, liner material was extended under the flow path to assure interception and <br />diversion into the lined ditch. The liner was then covered with approximately 1 foot of <br />overburden material and the ditch and disturbed area was seeded with the MLR seed mix <br />for the area (attached). The finished ditch traverses the MLR borrow area slope extending <br />from the existing groundwater diversion /lined diversion ditch northeast, to the old <br />upland runoff diversion ditch. This section will drain to the west around the tailings pond. <br />The impermeable clay layer underlies the old upland diversion ditch to the east of the <br />intersection so a 40 mil PVC liner was installed, below the clay contact, utilizing this <br />ditch to the east of the intersection. This section will drain to the east around the tailings <br />pond. A map is attached to show the flow direction and location of the completed <br />interception ditch. <br />The finished ditch is approximately 1.5 feet wide by 1 foot deep at the invert and was <br />intercepting and diverting a small flow around the tailings area at project completion. <br />Please contact me if there are any questions on this update report. <br />CC: Wally Erickson, DMG <br />Sincerely, <br />Larry Perino <br />Reclamation Manager <br />