ST Enclosure A

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(See Table 1 (on-site) and Table 3 (on and off-site) in Appendix C for project impacts categorized by Cowardin/HGM) The following wetland classes, per COWARDIN (1979) and Hydrogeomorphic (HGM) are found within the project and mitigation areas. For the purpose of this document these wetland classes are described below with the corresponding wetland number impacted by the project. A description of each wetland is contained in the Port’s wetland delineation for the project area (Port of Seattle, December 2000) and the Corps MFR confirming the wetland delineation (dated February 2001). In cases where the wetland contains more than one classification, it is listed under all applicable classes. A. Cowardin Classification 1. Forested Wetlands (PFO) - these wetlands contain woody vegetation over 20 feet (6 meters) tall (such as alder, cedar, hemlock, black cottonwood, and some species of willows, etc.) and covers at least 30% of the area. In mature forested systems, the deciduous trees are more than 60 years old and the coniferous trees are more than 80 years old. There are many individual trees within the project area which likely meet the 60- year-old criteria for mature forested wetlands, however most of the PFO systems in the project area are younger (average 20-40 years of age). The following wetlands/wetland complexes in the project area are considered PFO and/or contain PFO components: Miller Creek Basin: 1, 2, 3, 4, 5, 7, 9, 11, 12, 14, 18, 19, 21, W2, 35, 37, 39, A1, A6, A7, A8, A13, A14, A17, R4b,…

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