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segment of geotextile and sufficient circumferential area to allow visual observation of any <br /> potential damage to the underlying primary liner(60 mil HDPE). Ultimately, the full extent <br /> of the topmost geotextile drainage layer (down to a point immediately above the in-place <br /> tailing materials) was removed in order to provide full visual access to the underlying <br /> primary (60 mil HDPE) liner component and assess the full extent of damage to the liner <br /> system. <br /> VRI had retained, within Technical Revision No. 4 (Section 4.0: Non-Repair Options), the <br /> right to make a determination as to the technical and/or economic viability of undertaking <br /> liner system repair and re-certification. Based on the observed extent and severity of <br /> damage that the liner system had incurred, it was determined by VRI that it was both <br /> technically feasible and economically viable to proceed with liner system repair and re- <br /> certification, and VRI concluded contract arrangements with Colorado Lining International, <br /> Inc. (CLII) to commence said repairs at the earliest available date. <br /> The CLII repair crew arrived onsite on Wednesday, August 16, 2017 to commence repair <br /> activities. Mr. Randy Cosgrove was the CLII installation supervisor, the repair crew <br /> consisted of Mr. Carlos Rivera and Mr. Noe Saenz. CLII assigned Job No. 6398 to the <br /> repair effort. A schematic diagram of damaged/replaced areas, field recordation of repair <br /> and/or replacement actions (daily installation reports), and liner test results are provided <br /> in Attachment I: Colorado Lining International, Inc. — Liner Repair and Replacement <br /> Documentation. <br /> Upon completion of full exposure of the existing composite liner system, it was jointly <br /> determined by CLII and VRI that effort would be made to ensure that the existing liner <br /> system anchor trench not be disturbed. Accordingly, to protect the existing and fully intact <br /> anchor trench, and in order to facilitate future liner expansion, a "dedicated" anchor trench <br /> was excavated at a lateral distance of approximately four(4) to five (5) feet exterior to the <br /> periphery of the existing anchor trench for purposes of anchoring the topmost (and to-be- <br /> replaced) geotextile drainage layer component (i.e., the non-woven geotextile that <br /> overlays the primary 60 mil HDPE liner. This "dedicated" anchor trench was excavated to <br /> a depth of approximately three (3) feet. <br /> It was similarly determined (as the approved Plan incorporated leaving the existing tailing <br /> material in-place in the lowermost portion of the impoundment and immediately behind the <br /> concrete barrier wall) that the geotextile drainage layer would be cut approximately three <br /> (3) feet above the level of the impounded tailing, in order to allow overlapping of the to- <br /> be-installed (topmost) replacement geotextile drainage layer upon completion of the <br /> repairs. Peripheral tailing materials were, in turn, hand-shoveled back onto the main <br /> portion of the impounded tailing to further facilitate maximum overlap. Following <br /> overlapping placement of the replacement geotextile drainage layer, the earlier-removed <br /> quantities of tailing material were hand-shoveled back onto the overlap to ensure that the <br /> component(s) remained in position. <br /> 5 <br />