Ordinance - #89-21 - 09/12/1989 - Laserfiche WebLink

Home

Slowly Permeable Soils 1. Excavation for the purpose of constructing a soil treatment system must not be made in any soil layer having a percolation rate slower than 120 minutes per inch. 2. Excavation for the purpose of constructing a soil treatment system must not be made in a soil layer having a percolation rate slower than 60 minutes per inch unless the moisture content is lower than the plastic limit of the soil. 3. Drainfield rock must not be placed in contact with original soil having a percolation rate slower than 60 minutes per inch. 4. Where the percolation rate of the original soil is slower than 60 minutes per inch, at least 12 inches of fill material having a texture defined as sand must be placed between the drainfield rock and the original soil along the excavation bottom. 5. Construction equipment wheels or tracks must not be placed in contact with the bottom of the excavation during the construction of a soil treatment system in soils having a percolation rate slower than 15 minutes per inch. 6. The size of the soil treatment system must be based on an acceptance rate of 0.24 gallons per square foot, which is equivalent to a sizing factor of 4.2 square feet per gallons per day. 150o014G - FINAL TREATMENT AND DISPOSAL - ALTERNATIVE SYSTEMS Subd. 1 - General The contents of this section apply to the final treatment and disposal of the effluent of a system constructed in accordance with Section 150.01.4. The intent of this section is to provide sewage treatment solutions for those site or soil conditions where a standard system cannot be installed or is not the most suitable type of sewage treatment system. Subd. 2 - Fluctuating Groundwater 1. Where natural drainage will not provide four (4) feet of separation between the bottom of the soil treatment area and the highest known or calculated level of the water table, agricultural drain tile may be used to intercept or lower the seasonal high water table, except with shorelands of public waters. There shall be at least ten (10) feet of undisturbed soil between the sidewall of the soil treatment unit and the agricultural drain tile.