Agenda - Council - 05/24/2005 - Laserfiche WebLink

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c. If wastes will be discharged into a publicly owned treatment facility, identify the facility, describe any pretreatment provisions and discuss the facility's ability to handle the volume and composition of wastes, identifying any improvements necessary. Sanitary sewer waste will be conveyed by the trunk sewer to the Metropolitan WWTF in St. Paul, Minnesota. Th~ existing plant has adequate capacity to service the project's design average flow, therefore no improvements will be necessary. Expansion or'the Metropolitan WWTF is'anticipated within the next 20 years. d. If the project requires disposal of liquid animaJ manure, describe disposal technique and location and discuss capacity to handle the volume and composition of manure. Identify any improvements necessary. Describe any required setbacks for land disposal systems.. Not applicable. a. Describe any of the following geologic site hazards to ground water and alSo identify them on the site map: sinkholes, shallow limestone formations or karst conditions. Describe measures to avoid .or minimize environmental problems due to any of these hazards. Minimum depth (in t~et) Average depth Groundwater 15 Et (but 4 Et Groundwater 29 Et according to borings) Bedrock 59 Et Bedrock 90 Et Groundwater and bedrock information is for four wells in Section 20 in T32 R25 of Anoka County, fi.om the County Well Index (CWI). The first bedrock encountered is the Franconia formation. There are no known sinkholes, shallow limestone formations or karSt conditi.ons at the site. In addition to tile information obtained from the geologic survey, an in-depth geotechnical evaluation was performed on the Pulte Homes property in Fall 2004 that included 't5 soil borings and 55 test pits. The maximum groundwater elevation was found to be as shallow as 4 ft within numerous pits at the 10 Et or greater depth. The geotechnical report noted drainage characteristics for the property ranging from poorly drained for the silty sands and clays to fast draining for the sands. b. Describe the soils on the site, giving NRCS (SCS) classifications, if known.'Discuss soil granularity and potential for grodndwater contamination from wastes or chemicals spread or spilled onto the soils. Discuss any mitigation measures to prevent such contamination. According to the Soil Survey of Anoka County, soils on-the alignment are DnA (Dickman sandy loam, 0 to 2 percent slopes), Dp (Duelm loamy coarse sand), HuA, HuB, HuC (Hubbard coarse sand, 0 to'2 percent slopes, 2 to 6 percent slopes, and 6 to 12 percent slopes, respectively), Is (Isan sandy loam). The distribution of these soil types is shown in Figure 4. Type A soils (sand, loamy sand, or sandy loam) have low runoff potential.and high infiltration rates even when thoroughly wetted. They consist chiefly of deep, well to excessively drained sands or gravels and have a high rote of water transmission (greater than 0.3 in/hr). Since th~ rate of water transmission is high on a majority of the site, there is a risk of groundwater contamination from wastes or chemicals reaching the groundwater. Care will be taken to prevent spills. Type D soils (clay loam, silty clay loam, sandy clay,silty clay, or clay) have high runoff potential. They have very low infiltration rates when thoroughly wetted and consist chiefly of clay soils with a high swelling potential, soils with a permanent high water table, soils with a, claypan or clay layer at or near the surface, and shallow soils over nearly impervious material. These soils have a'¥ery Iow rate of water transmission (0 to 0.05 in/hr). -478-