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COR Wetland Mitigation Memorandum October 7, 2021 Page 7 Soils within the wetland were dominated by black and dark brown coarse sand, which is likely the soil present from construction. Hydrology was present as inundation for most of the basin, and saturation near the perimeter. Hydrology was present as inundation for most of the basin, and saturation near the perimeter. Inlet and outlet structures are present to assist with moderating hydrology within the site. Wetland Delineation Results—Wetland Area and Credits The wetland delineation was used to determine the amount and types of wetland present at each of the wetland mitigation site locations. During the wetland delineation, the location and extent of storm water features was also verified, although the mapping was completed using GIS resources and previous as- built maps of the areas. The extent of upland buffer was mapped using the extent of unmanaged vegetation in place currently. Areas within the parcel that are not functional buffer was not included. The area available for consideration as the mitigation site was verified to be within the drainage and utility easement identified within the recorded plat. A summary of the results in provided in Table 7. This includes areal estimates provided in the 2011 and 2012 monitoring reports, to show the progression from what was originally planned to the conditions ten years ago, to current conditions. Table 7: Summary of NWC and PVC Credits Proposed and Created Feature Area (Square Feet) Proposed T 2011/2012 Current (2021) Charter Site New Wetland (Shallow Marsh) 26,181 17,973 40,154 New Wetland (Wet Meadow) 191819 291514 0 New Wetland (Deep Marsh) 0 0 91862 Stormwater Treatment Area 19,476 71933 19,366 Upland Buffer 26,524 37,997 43,952 Subtotal 92,000 93,417 113,334 Northwest Site New Wetland (Shallow Marsh) 71592 71640 17,688 New Wetland (Wet Meadow) 171224 171717 0 New Wetland (Deep Marsh) 0 0 71086 Stormwater Treatment Area 41860 41659 51980 Upland Buffer 27,958 29,201 15,825 Subtotal 57,634 59,217 46,579 Total 149,634 152,634 159,913 Although a total area of 149,634 ft2 (3.44 acres)was proposed, a larger area of 159,913 ft2 (3.67 acres) is present. Specific to the area of wetland, a total of 70,816 ft2 (1.63 acres)was proposed, but a total of 747790 ft2 (1.72 acres) is present currently. This additional area of wetland was identified in 2011 and appears to be related to a larger area of wetland that was graded. This has increased further, which may be related to the site maturing or following a prolonged period of above average annual precipitation (2014-2019, according to the MN Climatology Working Group). The wetland is currently located at the toe of the slope and is not likely to expand beyond the current footprint. The increase in the total footprint is