2019.02.04 CC Packet - Laserfiche WebLink

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Effective April 28, 2015 Chapter Four Subsurface Sewage Treatment System Regulations ii. Concrete tanks must hold water for one hour, without loss, after the tank has been filled with water to the top of the tank, let stand for 24 hours, and then refilled to the same level; or iii. Fiberglass reinforced polyester or polyethylene sewage tanks must hold water without loss for one hour after being filled. (B) Sewage tanks that do not pass the tests listed in item A must not be used until repaired and retested. The repair and retest procedure must be repeated until the tank passes the test or the tank must not be used. 13.25 Tank Identification. (1) Sewage tanks must be marked near the outlet with: (A) The manufacturer's name. (B) The model number. (C) The liquid capacity. (D) The date of manufacture. (E) The maximum depth of burial. (2) The tank manufacturer or manufacturer's agent shall provide the information in Section 13.25(1) to the installer in writing. (3) The tank inlet or outlet must be clearly marked. (4) The installer shall submit the information in Section 13.25 (1) with the as -built drawing. 13.26 Sewage Tanks for MSTS, General. All holding or treatment tanks or vessels, including lined vessels and grease interceptors serving MSTS, must conform to the applicable requirements of this Section, except as modified in Section 13.26 through 13.30, or as designed by a professional engineer and approved by the Department or local unit of government. 13.27 MSTS Septic Tank Capacity. Septic tank capacity for MSTS or Other Establishments shall be determined by: (1) Total septic tank liquid capacity for a common tank serving multiple dwellings under gravity flow to the common tank is determined by multiplying the design flow by 3.0. (2) Total septic tank liquid capacity for a common tank serving multiple dwellings under pressure flow to the common tank is determined by multiplying the design flow by 4.0. (3) Common multiple septic tanks must be connected in series. Individual tanks connected in series or any compartment of a tank must have a capacity of more than one-fourth of the required to total liquid capacity. (4) For MSTS that have individual septic tanks at each dwelling, the individual tanks must meet the requirements of Section 13.5. (5) Total septic tank liquid capacity prior to other treatment devices shall be according to manufacturer's requirements or accepted standards. (6) Holding tanks serving Other Establishments must provide storage of at least five times the design flow. (7) An effluent screen or pressure filter must be used on all systems. If multiple septic tanks are used, the effluent screen must be placed in the last tank in the series and be provided with an alarm. Lint filters are recommended if the sewage contains laundry waste. (8) Total septic tank liquid capacity for systems employing individual tanks at each dwelling discharging into a collection system must be determined: (A) By a Minnesota licensed professional engineer; or (B) According to the Prescriptive Designs and Design Guidance for Advanced Designers, incorporated by reference under Section 5.2(4) of this Chapter. (9) Total septic tank capacity for other establishments with domestic strength waste is determined by multiplying the design flow by 3.0 if receiving sewage under gravity flow, by multiplying the design flow by 4.0 if receiving the sewage flow under pressure flow, or according to Section 13.8, 53 Washington County Development Code