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' IRIS MITIGATION AND DESIGN,INC. <br /> IRIS 2022 Arapahoe Street <br /> MITIGATION AND DESIGN,INC. Golden,Colorado 80401 <br /> Environmental Consulting Phone: 720-272-1985 <br /> bleisure@irismitigation.com <br /> Therefore, by August 2013, the 293 establishing planted trees and shrubs had achieved 89 <br /> percent establishment success and the planted willow stakes had achieved 92 percent <br /> establishment success. The 0.25 acre seeded areas all had good grass establishment equal to <br /> at least 50 percent overall cover throughout (see Appendix A - Photos 1 through 16, and Table <br /> ' 4). <br /> ! IRIS planned to collect more detailed seeded area success data in September 2013 through <br /> plot and transect data collection. However, mid-September rains created flood conditions <br /> ! destroying much of the seeded areas, as detailed below. <br /> SEPTEMBER 2013 FLOOD EVENT (the "Flood") <br /> ! The Site experienced an epic, greater than 500-year, storm event that released over 20 inches <br /> of rainfall during the week of September 9, 2013. The highest amount of rainfall on record for <br /> the Flood occurred in the vicinity of the Site, and along the associated section of the Creek. It <br /> caused destructive flows along the Creek and adjoining steep drainages such that rock, gravel, <br /> sediment and woody material (including trees up to and including 3 to 4 feet in diameter) <br /> entered the Creek. This rapidly moving river of rock, gravel, and woody material clogged <br /> culverts, deposited sometimes large amounts of material in the existing creek bed, and <br /> ! destroyed up to 50 percent of riparian vegetation along the Creek due to scour, erosion, and <br /> depositional forces. The force of the flow, and associated eroded materials so entrained, <br /> ! destroyed several miles of Glencoe Valley Road (the "Road"), located parallel to the Creek, <br /> ' Schwartmalder Mine Phase 1 -2013 Mitigation Monitoring Report Page 5 <br /> May 31,2014 <br />