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Basin A Basin A is a 3.63 acre partially drained remnant severed from a much larger wetland complex southeast of I -35W. Basin A is a partially drained combination of palustrine emergent, scrub shrub and forested wetland (PEMC /PSS /FO1 Cd; Circular 39 Types 1L/2/6). This remnant was historically ditched and drains first to an off-site road ditch and then via culvert under I -35W, both of which are lower in elevation than the subject wetland. Based on the presence of these drainage facilities and the character of existing plant communities, it is evident that this wetland remnant once had a much wetter hydrologic regime. The emergent portion of Basin A is dominated by reed canary grass (Phalaris arundinacea; FACW +) and has smaller remnants of tussock sedge (Carex stricta; OBL) and Canada bluejoint (Calamagrostis canadensis; OBL) in the deeper portions of the wetland basin. With partial drainage, the fringes of the basin have been invaded by woody species, including cottonwoods (Populus deltoides; FACW, trembling aspen, and paper birch. Speckled alder (Alnus rugosa; OBL) still occupies a portion of the basin. A small stand of tamarack trees (Larix laracina; OBL) once existed within the wetland. With the drainage that has occurred, only a one or two of these trees lies within the delineated wetland boundary. The remaining trees are now on the effectively drained fringes the former wetland. Basin B About 1.24 acres of Basin B lies within the project site. The remainder of this wetland lies off -site to the northeast. Basin B is a partially drained combination of emergent, scrub shrub and forested wetland (PEMC /PSS /FO1 Cd; Circular 39 Types 1L/3/6 shallow marsh, shrub swamp and bottomland hardwoods. This wetland lies in the very northeast corner of the project site and will not be affected by development. Proposed Impacts The complete wetland mitigation plan can be found in Exhibit D. Basin A The proposed project would entail 2.48 of fill and 1.15 acres of excavation within Basin A. The proposed fill is necessary due to large footprint of the type of development being proposed, the size and configuration of the project site and the central location of the subject wetland in the most visible area of freeway frontage. The applicant proposes sequencing flexibility (as defined in Minn. Rules 8420.0520 Subp. 7a) given the substantially degraded state of Basin A and the higher level of wetland functions and values anticipated in the proposed replacement wetlands. The proposed excavation would be for the purpose of providing stormwater ponding to pre -treat all runoff from impervious surfaces prior to its discharge to the larger wetland complex to the east. The proposed pond location is due its topographic position and the location of the existing outlet structure under the freeway. Basin B Impacts to Basin B have been totally avoided in the design of proposed project. Applicable Regulatory Framework and Mitigation Requirements Wetland Conservation Act The 2.48 acres of proposed wetland filling impact will be regulated under the Minnesota Wetland Conservation Act (WCA). Unavoidable impacts must justified and offset through compensatory wetland replacement at a minimum 2 to 1 acreage ratio. The WCA requires a sequencing analysis to demonstrate that the proposed impacts are unavoidable. Excavation within wetlands is only regulated under the WCA if proposed in the semi - permanently or permanently flooded portions of Types 3, 4 or 5 wetlands. Excavation within saturated, temporarily flooded and seasonally flooded wetlands is not regulated under the WCA, provided Page 13 of 28 Draft EAW Lino Lakes Marketplace May 11, 2001