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Attachment A Not applicable. ii.Stormwater –Describe the quantity and quality of stormwater runoff at the site prior to and post construction. Includethe routes and receiving water bodies for runoff from the site (major downstream water bodies as well as the immediate receiving waters). Discuss any environmental effects from stormwater discharges. Describe stormwater pollution prevention plans including temporary and permanent runoff controls and potential BMP site locations to manage or treat stormwater runoff. Identify specific erosion control, sedimentation control, or stabilization measures to address soil limitations during and after project construction. The site will utilize multiple infiltration ponds to treat stormwater, as well as underground treatment systems below the proposed parking areas. The final design and size willbe determinedduring the schematic design phase. Ultimately, the ponds and detention systems will outlet the treated stormwater to the adjacent drainage channel to the west and north of the site, which drains into the regional pond near Oasis Park to the north of the site.Itwill be designed to meet the Rice CreekWatershed District requirementsfor rate control and water quality. A stormwater pollution prevention plan (SWPPP) will be developed in accordance with the NPDES permit administered by the MPCA, the City of Roseville, and Rice Creek Watershed District. The SWPPP will cover temporary measures to prevent pollution during construction. Silt-fence, bio-rolls, and fabric covers for existing catch basins will be used to provide erosion and sediment control during construction and site disturbance. iii.WaterAppropriation–Describe if the project proposes to appropriate surface or groundwater (including dewatering). Describe the source, quantity, duration, use, and purpose of the water use and if a DNR water appropriation permit is required. Describe any well abandonment. If connecting to an existing municipal water supply, identify the wells to be used as a water source and any effects on, or required expansion of, municipal water infrastructure.Discuss environmental effects from water appropriation, including an assessment of the water resources available for appropriation. Identify any measures to avoid, minimize, or mitigate environmental effects from the water appropriation. Water appropriation is not anticipated for the project; however, if dewatering is required for construction, a permit will be obtained from the Minnesota Department of Natural Resources (DNR). The proposed project will abandon two Minnesota County Well Index (MCWI) monitoring wells, which was identified by the geotechnical engineer during site reconnaissance. These wells will be properly sealed and grouted according to the current well sealing guidance prior to redevelopment of the site, and the appropriate permits will be obtained from MDH. Twin Lakes Station11 March 2020