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PERMIT #: M- 1980 -244 <br />INSPECTOR'S INITIALS: TC1 <br />INSPECTION DATE: April 29, 2013 <br />OBSERVATIONS <br />The Division conducted a monitoring inspection of the site on April 29, 2013. Mr. Timm Comer (CC &V) & Mr. Adrian <br />Brown (consultant) were present for a pre- inspection meeting and for the inspection. The primary focus of this inspection <br />was to observe construction activities associated with the ECOSA Field Fit Ditches and monitor solution levels. <br />Pre - Inspection Overview: <br />Mr. Comer indicated the following activities are in progress: <br />• Four new nested compliance wells have been installed in Arequa Gulc near the confluence with Cripple Creek. <br />The wells were being developed on the day of this inspection. <br />• CC &V is collecting baseline data for the Grassy Valley monitoring wells downgradient of the ECOSA. <br />• The new fuel island (TR -63) is now operational. The old fuel island is being decommissioned. <br />• CC &V is installing a water supply line upgrade for their fresh water system. <br />• CC &V is runnig wires from one deep piezometer (750 ft) that will be covered by the ECOSA to facilitate remote <br />future monitoring. <br />Inspection: <br />Mr. Brown provided an overview of the hydrogeology in the Grassy Valley area. Photos 1 and 2 show the <br />ECOSA encroaching into Grassy Valley. The first of three ECOSA drainage mitigation ditches was observed <br />(see Photos 3 and 4). The ditch construction appeared to meet or exceed the design specifications. The design <br />was for a minimum slope of 1 %. The first ditch is constructed at roughly 3 %. The natural segregation of <br />overburden (see Photo 5) will cause the ditch to fill' with coarser rock to facilitate infiltrated water to migrate <br />towards the diatreme, ultimately being expressed at the Carlton Tunnel discharge. <br />Mr. Lawrence Myers presented an overview of the new Arequa Gulch compliance CRMW5 A, B, C and D <br />wells (see Photo 6). They are completed at roughly 205 ft, 143 ft, 60 ft, and 27 ft, respectively. CC &V has <br />constructed a small diversion channel around the wells (see Photos 7 and 8). Mr. Myers pointed out the Arequa <br />Gulch discharge flume AG 2.0 (see Photo 9). <br />The new mill platform retaining walls are complete (see Photos 10 and 11). Clearing, grubbing, and topsoil <br />salvage are continuing in Squaw Gulch (see Photo 12). <br />The new Phase IV drain mitigation collection pipes (for diverting upgradient flow from the north end of Phase <br />IV to the south, thereby reducing solution volume to the part of the system that overflowed in April 2012. <br />The inspection continued as the Division visited each of the high and low solution collection system transducers <br />and recorded water level values. The recording sheet is included as Attachment A, and the values are <br />summarized below in the Transducer Readings. <br />The Arequa Gulch underdrains were inspected. The South Underdrain discharge was determined to be 0.78 <br />gpm (measured 2.5 quarts in 48 seconds). Both the North Underdrain and the AG /Spring were dry. Both the <br />A35 pumpback and B63 pumpback lines were dry. No flow was observed in the Arequa Gulch flume (AG 1.5- <br />001 A). <br />Transducer Readings: <br />Phase I Hieh Volume Solution Collection (readines in ft) <br />Pump #299 / XDCR #xx Pump #300 / XDCR #00 <br />43.1 36.6 <br />Page 2 of 10 <br />