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page 10 251491 Domestic Sealed 115 ft. b. Describe effects from project activities on water resources and measures to minimize or mitigate the effects in Item b.i. through Item b.iv. below. i. Wastewater - For each of the following, describe the sources, quantities and composition of all sanitary, municipal/domestic and industrial wastewater produced or treated at the site. 1) If the wastewater discharge is to a publicly owned treatment facility, identify any pretreatment measures and the ability of the facility to handle the added water and waste loadings, including any effects on, or required expansion of, municipal wastewater infrastructure. The development will increase average day sanitary sewer flows by an estimated 230,000 gallons per day (274 gallons/unit/day for average flows), and was calculated based on the Metropolitan Council’s Flow Variation Factors for Sewer Design from the 2040 Water Resources Policy Plan. These flows will ultimately travel to the Metropolitan Council’s Metro Wastewater Treatment Plant via meter M104. It is planned that the wastewater from the development will enter the system at the 24” diameter PVC in the alley south of 27th Avenue NE. The pipe and downstream system is capable of handling the increased sanitary flows proposed from the development, according to the City’s sanitary sewer model. Depending on the final grading of the site, a 600 gpm sanitary sewer lift station with a 10” inner diameter forcemain will likely be required. St. Anthony will surpass the Metropolitan Council’s wastewater projections, as outlined in its Water Resources Policy Plan. The Council currently does not predict a significant increase in wastewater flows from the City between 2010 and 2040, with wastewater flows meeting their expected peak of 0.76 MGD in 2020. The City’s average daily wastewater flows from 2010 to 2015 were 0.73 MGD. Therefore, the Council is planning to treat, at most, an increase of 0.03 MGD, while this project will increase flows by an estimated 0.23 MGD, bringing the City’s total to 0.96 - 0.99MGD. The development may therefore require review by the Metropolitan Council to determine if their interceptor can accommodate the increase in flows. 2) If the wastewater discharge is to a subsurface sewage treatment systems (SSTS), describe the system used, the design flow, and suitability of site conditions for such a system. Wastewater will not discharge to a subsurface sewage treatment system. 3) If the wastewater discharge is to surface water, identify the wastewater treatment methods and identify discharge points and proposed effluent limitations to mitigate impacts. Discuss any effects to surface or groundwater from wastewater discharges. Wastewater will not discharge to surface water. 45