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pumping to Lake Owasso is unknown and difficult to estimate due to the infiltration characteristics of the site. It is possible that pumping would only occur during very large and inftequent rain events. If this is the case, pollutant discharge to Lake Owasso would be minimal. Because of the granular nature of the soils on the site, the site could be considered Hhigh risk" with regard to groundwater contamination. While the majority of pollutants from urban run-off that infiltrates into the ground would be filtered in the first feet of soil, some pollutants that are soluble in stormwater may eventually reach nearby aquifers, This condition, however, has existed on this site since the development of the adjoining residential areas and would not be greatly exacerbated by the proposed development. Wetlands The delineated wetlands on-site provide valuable wildlife habitat, stormwater filtration, flood control, and groundwater recharge. In addition, they are an important aesethic feature to the proposed residential development. As such, it is important that their integrity is preserved, in order to protect existing wetland vegetation and wildlife habitat, it is necessary to limit the amount of water elevation bounce during rain events. As such, the amount of stormwater available in wetlands storage may be limited requiring additional storage to be constructed in non-wetland areas. Staff is working with the developer to analyze the impact of the proposed stormwater system. As of the date of this report, this issue has not been resolved, The proposed grading plan shows two small wetland areas that will be filled. The first is in Wetland Basin 6 and is needed to construct the new roadway to Dale Street. The second is a small amount offill on the north side of Wetland Basin 1. The Wetland Conservation Act requires that these encroachments be approved and mitigates at a 2: 1 ratio. No mitigation is currently shown in the submitted proposal. Grass Lake Water Management Organization The proposed development is within the Grass Lake Water Management Organization (GLWMO) boundaries. This organization, governed by a board appointed by the Cities ofRoseville and Shoreview, manages water resources in that area that eventually drains to Grass Lake. Grass Lake is a large wetland located in the City of Shoreview north of 1-694 and west of Rice Street. This area includes Snail Lake, Lake Wabasso, and Lake Owasso. GL WMO was originally formed to address flooding concerns within the watershed and has constructed a number of improvements to improve both flood storage and stormwater quality. More recently, this organization has focused primarily on water quality issues in an effort to protect our major lakes. At its January 30, 1995, meeting, the school district presented its proposed development to the GL WMO Board. Following discussion, the board passed a resolution to be forwarded to Roseville The resolution identifies the following concerns: ~ The potential pumping from Wetland Basin 5 should be analyzed with regard to flooding on Lake Owasso. Some properties, especially on Sandy Hook Drive, are very susceptible to high water levels on Lake Owasso. 11