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PERMIT #: M-1980-244 <br />INSPECTOR’S INITIALS: TC1 <br />INSPECTION DATE: November 22, 2016 <br /> <br /> <br />Page 2 of 7 <br /> <br />OBSERVATIONS <br /> <br />The Division conducted a monitoring inspection of the site on November 22, 2016. Messrs. Jeff Campbell, Erik <br />Munroe, Cheyne Mann and Ms. Clara Steward represented the Operator during various parts of the inspection. <br />Tim Cazier represented the Division. The site received approximately six inches of snow very early in the <br />morning on the day of the inspection. As fresh snow covered most of the ground, the planned inspection agenda <br />was truncated to the following facilities and areas: <br /> High Grade Mill (HGM) Vat Leach Area; <br /> East Cresson / Altman Backfill; <br /> Arequa Gulch Valley Leach Facility (AGVLF) select (accessible) leak detection system (LDS) sumps. <br /> <br />Site Inspection: <br />High Grade Mill: The Division was accompanied by Messrs. Munroe and Mann to the HGM leach tank secondary <br />containment area for the purpose of understanding the mine ’s approach to increasing the secondary <br />containment storage capacity proposed as part of TR-81. CC&V currently proposes the use of a 1/4-inch <br />continuous steel plate combined with a rubber membrane seal. A detail drawing provided by CC&V’s <br />engineering consultant (FL Smidth) shows five different configurations for the steel plate system. The purpose <br />of the Division’s visit to this area was to understand how continuity between the five designs could be achieved, <br />as the plate is proposed to be mounted on the inside of the concrete stem wall in some locations, and centered <br />on the top of the wall in others. The inspection did not clarify how this was to be accomplished and the mine ’s <br />Process Group representative was not familiar enough with the proposed design to offer any insight. <br />Observations of the area did reveal some particular challenges to the proposed design, particularly in the <br />northeast corner near the stairwell (see Photo 1) and potential interference from pipes exiting the tanks at low <br />levels (see Photos 2 and 3). The Division also noted that each of the nineteen perimeter columns (see Photo 4) <br />will require four bends each (two inside and two outside corners) on the inside wall-mounted plate. <br />AGVLF Leak Detection System Inspection: The Division was accompanied by Mr. Campbell and Mr. Jay Ballard <br />(CC&V Process group) to ten accessible AGVLF leak detection system sumps. Access was limited due to roads <br />that had not yet been plowed. LDS sump numbers: 1, 2, 3, 6, 7, 9, 12, 13. 14, and 15 were visited and or pointed <br />out. Snow-covered uneven rocky ground prevented safe foot access to a few of these LDS sumps (e.g., LDS #7 <br />shown in Photo 5). Sumps 3, 9 (see Photo 6) and 13 were dry; Sumps 6 and 12 (see Photo 7) had some water <br />in the bottom. Mr. Campbell indicated that sumps which frequently have water in them have been fitted with <br />a dedicated pump (see LDS #6 setup in Photo 8) and a rock placed in the bottom for quick assessment as to the <br />depth of water collected is sufficient to pump out and sample. <br />East Cresson / Altman Backfill: The Division visited the ECOSA/Altman backfill transition area with Ms. Steward <br />and Ben Larson from CC&V Engineering. Blowing snow reduced visibility sufficiently to prevent suitable <br />photographs. Photo 9 from the Division’s September 26, 2016 aerial inspection shows the ECOSA and Altman <br />backfill area. We discussed the need for additional stability analyses, primarily for the south slope of the Altman <br />backfill. The Division committed to providing a supplementary adequacy letter to address this. The letter was <br />sent on November 23, 2016. <br />Summary: <br />1. Fresh snow limited the scope of the inspection.