2021-07-29_INSPECTION - M2001022

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r To: Ms. Fancher-English Date: July 28,2021 Page 3 RESULTS AND DISCUSSION ' Existing Reclamation Slopes ' Sheet 1 shows the results of the 38 cross sections evaluated. All show compliance with Rule 3.1.5(7). For Zones 9, 20, 25, 26 and part of 27: ' • Zone 9: Both sections(Zone 9a and Zone 9b) show slopes at or shallower than 3H:1 V for 15 feet horizontally from water's edge, and flatter below the water surface ' • Zone 20: Both sections (Zone 20a and 20b) show slope compliance because the average slopes 15 feet and 20 feet horizontally from water's edge (above and below water level, respectively) are shallower than Rule 3.1.5(7) requirements 0 Zone 25: Section Zone 25a is shallower than the Rule requirement. Section Zone 25b averages 31-1:1 V for 15 feet from the water's edge • Zone 26: Above the water level,both sections show the slopes are gentler than Rule requirements. Below the water level, the average slopes are at the requirement Part of Zone 27: Meets average reclamation slopes The common factor with the Zones 20 through 27 is the presence of shoreline erosion, providing irregular topography along the slope. The irregular topography over short ' distances has not affected the overall average slope as shown in the cross sections. These erosional features are commonplace in all similar ponds along the Front Range where wind generated waves either pound and erode the shoreline,or where retreating water erodes the bank. Our experience is that they are limited in depth and heal over time. They do not typically result in deterioration of the entire slope, especially after vegetation establishment. ' King Y Surve Comparison ' Most of the reported slopes in the King Survey were too short and biased by local irregularities(e.g.,plow lines from drill seeding and cross ripping placed for soil retention and seed germination) for us to use in comparison. To calculate slopes, the approach ' should utilize the elevation at the water's edge,the average elevation at least 15 and 20 feet horizontally from the water's edge,above and below the ponded surface,respectively. The calculated slope above and below the water is then calculated as the difference between the elevations divided by the horizontal distance. Thus, we used the few King Survey slope calculations that were of appropriate length in our comparison. Sheet 2 summarizes the comparison between the King Survey and the PLS Corporation survey and our interpretation. Zones 12 and 19 show that the beginning and ending points the King Survey 20210727_SlopeEvaluatlon DRMS RTC_SFE.docx T E L E S T O 1