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June 4,2013 C-1982-057/Seneca 11-W Mine JLE <br /> impoundment was measured using an inclinometer and found to be about 34%or at a 3:1 horizontal to vertical <br /> ratio. Overall it appears the impoundment was constructed as it is depicted on the As-Built Drawing No. 13-91)in <br /> the permit except that the outslope of the embankment was constructed at a 3:1 horizontal to vertical ratio as <br /> opposed to a 3.5:1 horizontal to vertical ratio. However, Pond 017 was designed to have a 3:1 horizontal to <br /> vertical ratio outslope as depicted on Drawing 13-8B in the permit. The Operator has not provided the required <br /> documentation that the SEO has approved the retention of this impoundment in accordance with Attachment 20-2, <br /> Appendix 20-2.2 of the permit. This documentation must be submitted prior to any bond release for the <br /> impoundment. <br /> A small .5 acre parcel near the bottom of the PM drainage is under consideration for Phase I bond release. The <br /> Operator has constructed a surge tank; PM 1-1, in this area. This tank was holding a small amount of water. The <br /> PVC discharge outlets were in place and the spillway was clear and functional. The embankment appeared stable. <br /> Pond 016 is holding water and discharging. The primary spillway is partially obstructed with logs and will need to <br /> be cleaned. The Division checked the configuration of the pond to determine if it was constructed in accordance <br /> with the As-Built approved in the permit. The top width of the embankment was 15 feet. The emergency spillway <br /> bottom width was found to be about 20 feet and at times greater. The emergency spillway was rip-rapped. The <br /> principle spillway culvert was 24 inches in diameter. The outslope of the impoundment was measured using an <br /> inclinometer and found to be about 32%or at a 3.1:1 horizontal to vertical ratio. Overall,it appears this pond is <br /> constructed in accordance with the approved plan as depicted in Drawing No. 13-9a in the permit. However,the <br /> Operator has not provided the required documentation that the SEO has approved the retention of this <br /> impoundment in accordance with Attachment 20-2,Appendix 20-2.2 of the permit. This documentation must be <br /> submitted prior to any bond release for the impoundment. <br /> The lower portion of drainage PM-2 is under consideration for Phase I bond release. This channel was partially <br /> relocated during the repairs that were conducted around Pond 016. The channel is rip-rapped and stable. The <br /> bottom width of the channel was measured to be about 15 feet which is a little larger that it was designed. A small <br /> branch of the PM-2A drainage is located within the Phase I bond release boundary around Pond 016 and connects <br /> to PM-2. This drainage appears stable. The Division walked the edge of these drainages with a YUMA GPS unit <br /> to map the location of these channels. The line feature collected with the GPS unit was downloaded and projected <br /> in ArcMap®and overlaid onto a geo-referenced Exhibit 20-2 map depicting the post mine topography and <br /> drainages. It appears the Operator has constructed these drainages in the correct location. Both drainages appear <br /> to have been constructed wider than the approved design which would increase their capacity. Otherwise they <br /> appear to have been lined and stabilized in accordance with the design. <br /> Stock tank T-5 was holding water but was not discharging. The embankment was stable and vegetated. Exhibit <br /> 13-27 of the permit contains certified as-built plans for each stock tank. The pond appears to be the proper <br /> configuration. All of the proper documentation has been submitted for this stock tank to be left as a permanent <br /> impoundment. <br /> Stock Tank T-2 was holding water but was not discharging. Exhibit 13-27 of the permit contains certified as-built <br /> plans for each stock tank. The pond appears to be the proper configuration. All of the proper documentation has <br /> Number of Partial Inspection this Fiscal Year: 12 <br /> Number of Complete Inspections this Fiscal Year: 4 <br /> Page 6 of 12 <br />