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COR Wetland Mitigation Memorandum October 7, 2021 Page 4 Field notes, samples, and photographs were taken at representative locations in each wetland basin, with data transect locations following spacing guidelines in the Regional Supplement. The respective wetland and upland plots for each wetland were documented on Wetland Determination Data Forms (Appendix A). Relevant photographs of the site and representative sample locations are included in Appendix B; all other photographs will be retained on file at SEH. Wetland plant species nomenclature follows the National Wetland Plant List(USACE 2016). Identification was aided with field guides for the region. Vegetation was sampled in nested circular plots: 5-ft radius for herbaceous species, 15-ft radius for shrubs, and 30-ft radius for trees and vines. Soils were observed for hydric soil characteristics. Soils were examined in cores taken with a Dutch auger. Soil profiles were observed at a depth necessary to confirm hydric soil characteristics. Typical soil profile depths are typically within 18-24 inches below ground surface to allow for: (1)observation of an adequate portion of the soil profile to determine presence/absence of hydric soil characteristics; (2) observation of hydrology including depth to the water table and saturated soils; and, (3) identification of disturbances (e.g., buried horizon, plow line, etc.). Soil color determinations were made using Munsell Soil Color Charts (Gretag-Macbeth 1994). Site soil characteristics were compared to those mapped and described in the Soil Survey for Anoka County(USDA 2021). Hydric soil characteristics were compared to those identified in the Northcentral and Northeastern Regional Supplement(USACE 2012)and the most recent version of the NRCS publication Field Indicators of Hydric Soils in the United States, Version 8.1 (USDA 2017). Primary and secondary indicators of hydrology were identified in the field to determine the presence or absence of wetland hydrology, as described in the Northcentral and Northeastern Regional Supplement (USACE 2012)and are listed in each wetland description. Subsurface wetland hydrology indicators were examined using the soil cores and/or soil pits as deep as 24 inches. Wetland classification follows the methods described in Wetlands and Deepwater Habitats of the United States(Cowardin, et al. 1979)that is used by the USFWS NWI. The Circular 39 classification (Shaw and Fredine 1956) is also provided. Wetland classification is also provided following Wetland Plants and Plant Communities of Minnesota & Wisconsin (Eggers and Reed 2014), which is used for classifying wetlands for permitting-related activities under the Minnesota Wetland Conservation Act (WCA) and the USACE Final St. Paul District Policy for Wetland Compensatory Mitigation in Minnesota (USACE 2009). Wetland boundaries were located and marked with pin flags with "WETLAND BOUNDARY'to allow for field review. The locations of the delineated wetland boundaries were collected with a sub-meter accuracy Global Positioning System (GPS) unit and mapped. The results of the delineation are shown on Figures 3 and 4. The sample points noted identify where data was collected. Wetland Delineation Results—Charter Wetland The Charter mitigation wetland is comprised of a large central wetland, with three storm water treatment areas, and a perimeter of upland buffer. A pedestrian bridge crosses the site, and a constructed platform is present on the northeast side to allow people to overlook the site. The wetland is dominated by hybrid cattail (Typha glauca), which is present throughout the basin. The three (3)storm water treatment areas are also dominated by hybrid cattail. The perimeter of the wetland has some transition to wet meadow as hydrology is drier here than the center of the basin, but it was mapped as Shallow Marsh with an eastern area of deep marsh where water depths are sufficient to prevent emergent vegetation from being established. While the majority(>90%)of the wetland area is