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15. Water quality—surface-water runoff. <br /> a. Compare the quantity and quality of site runoff before and after the project. Describe permanent controls to manage or <br /> treat runoff. Describe any storm water pollution prevention plans. <br /> The quantity and quality of site runoff will not change as there is not a significant change in impervious surfaces from <br /> this project. <br /> b. Identify routes and receiving water bodies for runoff from the site; include major downstream water bodies as well as <br /> the immediate receiving waters. Estimate impact runoff on the quality of receiving waters. <br /> Existing storm water intakes will collect runoff and discharge it to the Mississippi River. Runoff from the site should <br /> have no impact on the receiving water. <br /> 16. Water quality—wastewater. <br /> a. Describe sources, composition and quantities of all sanitary, municipal and industrial wastewater produced or treated at <br /> the site. <br /> The proposed site will receive domestic and industrial wastewater. The facility will be improved to handle an AWW flow <br /> of 3.55 MGD with CBOD and TSS loadings of 8,518 lb/day and 7,808 lb/day respectively. <br /> b. Describe waste treatment methods or pollution prevention efforts and give estimates of composition after treatment. <br /> Identify receiving waters, including major downstream water bodies, and estimate the discharge impact on the quality of <br /> receiving waters. If the project involves on-site sewage systems,discuss the suitability of site conditions for such systems. <br /> The expanded treatment facility will include screening,grit removal, primary clarification, biological treatment with <br /> trickling filters and activated sludge, final clarification, sand filters, and disinfection. <br /> The limits for the discharge water are expected to be as follows: <br /> CBOD5-25 mg/I <br /> TSS-30 mg/I <br /> Fecal Coliform -200/100 ml <br /> Mercury-6.9 ng/I <br /> pH -6.0-9.0 SU <br /> Phosphorus- 1.0 mg/I <br /> C. If wastes will be discharged into a publicly owned treatment facility, identify the facility, describe any pretreatment <br /> provisions and discuss the facility's ability to handle the volume and composition of wastes, identifying any <br /> improvements necessary. <br /> NA <br /> d. If the project requires disposal of liquid animal manure, describe disposal technique and location and discuss capacity <br /> to handle the volume and composition of manure. Identify any improvements necessary. Describe any required <br /> setbacks for land disposal systems. <br /> NA <br /> 17. Geologic hazards and soil conditions. <br /> a. Approximate depth (in feet)to Groundwater 20 minimum; 30 average. <br /> Bedrock: 100 minimum; 150 average. <br /> Describe any of the following geologic site hazards to groundwater and also identify them on the site map:sinkholes, <br /> shallow limestone formations or karst conditions. Describe measures to avoid or minimize environmental problems due <br /> to any of these hazards. <br /> No geological site hazards have been indentified. <br /> b. Describe the soils on the site, giving U.S. Soil Conservation Service (SCS)classifications, if known. Discuss soil <br /> granularity and potential for groundwater contamination from wastes or chemicals spread or spilled onto the soils. <br /> Discuss any mitigation measures to prevent such contamination. <br /> Soils consist of 1/2 to 3 1/2 feet of silty sand fill or topsoil at the surface. Naturallly deposited glacial outwash sands <br /> were present below the fill to depths of 20-30 feet. Glacial till consisting of silty sand was present at depths of 35-45 <br /> feet. The sands contained variable amounts of gravel,with some layers of gravel and occasional cobbles. <br /> www.pca.state.mn.us 651-296-6300 800-657-3864 TTY 651-282-5332 or 800-657-3864 • Available in alternative formats <br /> wq-wwtp2-20 • 8117112 Page 5 of 7 <br />