Agenda - Environmental Policy Board - 01/18/2017

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Item-by-item guidance Chapter 10. Geology, soils,topography/land forms This item provides a basic understanding of geology and soils in the project area. This information will be used in other EAW items to understand potential environmental effects from groundwater contamination,erosion,or soil suitability for the proposed project. Other EAW items that may be more appropriate for detailed discussion on environmental effects include Item I I.b.ii.for erosion and Item 12 for groundwater contamination. a. Geology Describe the geologic features,including any geologic or landform features of special concern. Possible sources of information include: site surveys, soil surveys,topographic maps,county sanitation or health departments,the Minnesota Department of Health,USGS,the Minnesota Geological Survey-County Geologic Atlas,or other maps of state bedrock geology, surficial geologic map,or Karst features.The source of information about geologic features should be provided, such as whether geotechnical studies were done or if the information was taken from a geologic atlas. Once the geologic features are described,discuss potential environmental effects on those features that may result from the project. If any special concern features are present at the site,the EAW should describe measures to prevent potential groundwater contamination or other problems related to such feature or other mitigation efforts the project proposes to address potential environmental effects. b. Soils &topography Describe the types of soils present using the Natural Resources Conservation Service (MRCS)classification system. Soil surveys showing this information are available from the county offices of the University of Minnesota Extension Service, and soil and water conservation districts. If several soil types exist on the site,a soils map can be helpful. The NRCS maintains an internet-based application called the Web Soil Survey. If this data is available in the project area,this web tool should be used to identify soils and any limitations of those soils. Additional Resources: • The NRCS Web Soil Survey is located at: http://websoilsurvey.nres.usda.gov/app/HomePage.htm • USGS Hydrologic atlases: http://pubs.usgs_gov/ha/ • MNGS County geologic atlases: http://www.mngs.umn.edu/county atlas/countyatlas.htm • Site-specific soil boring logs. Discuss the soil suitability as it relates to project features such as erosion, stability, and strength. Soil series information can be used to identify physical properties,engineering features, and limitations.This information should be used to identify potential problem areas and identify measures to address those areas.Detailed discussion of erosion control, stormwater management and effects to water quality should be discussed in response to Item I I.b.ii.NOTE: If the project will grade or otherwise alter one or more acres, an NPDES Construction Stormwater permit is required from the MPCA. Steep slopes of 12 percent or more and erosion prone soils should be described and shown on the site plan or on a separate grading plan. Environmental Quality Board EAW Guidelines—October 2013 21