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Oakwater Ridge EAW 9 Findings of Fact and Conclusions, Response to Comments, and Record of Decision stormwater features (infiltration basins and stormwater ponds). The BMPs will control the rate of stormwater runoff discharges to comply with local and state requirements. The Minnesota Pollution Control Agency’s (MPCA) 2024 impaired waters list designated the portion of the Mississippi River adjacent to the project area as impaired. No other impaired waterbodies are within one mile of the project area. The project area is not within a wellhead protection area. Compliance with stormwater requirements will minimize and mitigate potential adverse effects on receiving waters. 7. Wetlands and Surface Waters. Two wetlands are present within the Project Area. A DNR qualified specialist from Midwest Natural Resources (MNR) found that both wetland features lacked any evidence of calcium carbonate and the soils throughout were generally sandy with some organic matter present but not similar to soils typically found in river terrace fens. The wetlands were determined not to be calcareous fens. The Mississippi River, a MnDNR Public Water Watercourse is along the western site boundary (within 300 ft of the project area). The project area was not within 1,000 feet of any Public Waters or Wetlands. No trout streams/lakes are present within or near the project area. There are no county/judicial ditches within the project limits. 8. Groundwater. Four groundwater seep locations were observed along the base of the hillslope in the lower cultivated portion of the project area associated with the wetlands. Groundwater levels encountered during the geotechnical exploration and piezometer water level readings are summarized in Table 15 of the EAW (Appendix B). Two of the piezometers documented water within 20-feet of the surface during the February and April 2025 readings. The extent/duration of dewatering is still being determined and an MnDNR water appropriation permit for temporary dewatering will be acquired if withdrawal exceeds 10,000 gallons/day or one million gallons/year. The project area is not within a wellhead protection area (WHPA). 9. Wastewater. Sanitary sewer would be extended to serve the commercial/residential development. The existing sanitary sewer connection is located at the intersection of 165th Avenue NW & Gateway Road NW. With project development a lift station will be installed to move sanitary sewer to the 165th and Gateway intersection for the project to have service. The gravity system and the lift station that serves this system are sized to accommodate development per the City Engineer. The total proposed/estimated wastewater flow is 0.2136 million gallons per day. 10. Water Appropriation. Project development will include the extension of a public water main. The City of Elk River's trunk water line is present east of the project area, at the intersection of 165th Avenue NW and Gateway Road NW. The Elk River Municipal Utilities (ERMU) operates the water system for the City and operates six water treatment plants, with capacity to treat eight million gallons of water per day. The four water towers within the City have the capacity to store four million gallons of water. The Project is located within the urban service area boundary and is not anticipated to require the expansion of any municipal water infrastructure. The development will require a DNR water appropriation permit for temporary dewatering and groundwater appropriation if withdrawal exceeds 10,000 gallons per day or one million gallons per year. The current extent of dewatering is not known at this time. 11. Hazardous Materials. A Phase 1 Environmental Site Assessment was completed in the fall of 2024. The onsite bus repair, maintenance, and fueling activities, particularly the bus maintenance garage, are considered a recognized environmental condition (RECs). Likewise, the diesel and gasoline underground storage tanks (USTs) located on the former bus lot and the gasoline USTs located near the garage are considered RECs. The Phase I ESA did not identify any Controlled Recognized Environmental Conditions (CRECs) or Historic Recognized Environmental Conditions (HRECs) within the site. A limited Phase II investigation was completed on January 2nd, 2025. Recommendations from the Phase II ESA will be followed and if contamination is found to be present, a Response Action Plan/Construction Contingency Plan (RAP/CCP) would be prepared for the project area to ensure contaminated media (if encountered) is managed in compliance with local, state, and federal regulations during redevelopment. Prior to site development, underground storage tanks will be removed in accordance with local, state, and federal standards. Surficial solid waste and hazardous chemicals/petroleum products will be removed and disposed of in accordance with local, state, and federal standards.