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Diversion Ditch RS North Portal D -D10 <br />Berms have no vegetation; however this is a newly constructed ditch and was not nominated for Phase <br />Il or III bond release at this time. Further, the ditch has recently been reseeded due to repairs as a <br />result of the storm events in August and September (see Photograph No. 12). <br />North Portal Mine Facilities Stockpile Area <br />As described previously in this report, North Portal drainage Ditches D -D6, D -D7, and D -D8 were <br />approved with PR -5 in July, 2012. These were constructed and seeded October 2012. They convey <br />a small portion of the East Diversion Ditch 2 runoff to a low-lying area in the southeast corner of the <br />North Portal adjacent to the Highline Canal. This design was requested by both the Bureau of <br />Reclamation, who oversees the Highline Canal, and the Grand Valley Water Users Association who <br />actually maintains the canal. This flow used to be directed into the canal via a 36 inch flume at the <br />end of the East Diversion. The flume was removed and disposed of in 2012 during construction of <br />the ditches. As seen in the attached Photograph No. 13, what appears to be evidence of significant <br />out flow occurred below the outfall of Ditch D -D8. This was the result of higher than normal <br />precipitation for a prolonged period (July through October). During this period, a total of 8.46 inches <br />fell in this locale as recorded at the NOAA Palisade Station located within the permit boundary <br />southeast of Interstate 70. The average precipitation for this same time period is 3.81 inches. On <br />August 24, 2013, a 24 -hr precipitation event of 1.63 inches occurred exceeding the 10 year, 24-hour <br />design capacity of 1.4 inches for Ditch D -D8. From these persistent storms, some sediment deposition <br />occurred along the edge of and adjacent to the Highline Canal where Xcel Energy has placed straw <br />wattles as a preventive measure. The area affected is very small and estimated to be about '/2 acre. <br />Ditch D -D8 was nominated for Phase I bond release only and it meets those requirements. This ditch <br />is repaired and functional. <br />South Fan <br />During the inspection, we noted the size of the South Fan reclaimed area (Photograph No. 14). We <br />had a discussion in the field that it seemed larger than 0.9 acres. SCC confirmed the size of the South <br />Fan reclaimed area and it is approximately 0.9 acres. <br />Roadside Borrow area <br />One of the drainages in the Roadside Borrow Area had damage apparently due to heavy runoff. The <br />riprap was washed out and the liner was exposed in one portion of the ditch (See Photograph No. 15). <br />SCC has already made the necessary repairs to this ditch. This was verified during an inspection <br />conducted in December, 2013. <br />For all of the areas described above as requiring maintenance, SCC has completed all necessary <br />repairs and will continue to maintain and monitor these locations throughout the bond liability period. <br />Page 13 <br />