(A) List of more restrictive adopted standards.
(1) An inspection pipe of 4 inches in diameter shall be installed on every drop box, cross pipe used to top-load, or distribution box.
(2) A SSTS shall be upgraded to conform in entirety with all requirements of this chapter when additional bedrooms or water-using appliances are added to a building or the SSTS is disconnected from a building and being replaced and connected to a new building such as in the case of replacement of mobile homes, modular homes, etc.
(3) The setback distance from an ISTS to the delineated boundary of a Type 4 or Type 5 wetland greater than 10 acres in size shall be 150 feet and the bottom and sides of trenches and beds shall be in original soils at least 3 feet above the saturated soil or bedrock. In cases where a property owner can demonstrate through legal description, or plat, or certified survey that there is insufficient depth on a lot to accommodate placement of the drainfield at the 150 foot setback, the Zoning Administrator may vary the setback administratively, but in no case shall the setback be less than 75 feet.
(4) The top of sewage tanks shall be buried no deeper from final grade than the tank manufacturer's maximum designed depth for the tank. This provision is adopted per the city's ability to do so as stated in Minnesota Rules, Chapter 7080.2000, C.
(5) On holding tanks, the maintenance hole of at least 20 inches in least dimension must extend through the cover to above final surface grade rather than follow the requirement in Minnesota Rules, Chapter 7080.2290, C.
(6) SSTS designs that will be used for a self-installed SSTS must include detailed construction/installation specifications and instructions meeting Department policy criteria for such designs.
(B) Determination of hydraulic loading rate and SSTS sizing. Table IX entitled "Loading Rates for Determining Bottom Absorption Area and Absorption Ratios Using Detailed Soil Descriptions" or Table IXa entitled "Loading Rates for Determining Bottom Absorption Area and Absorption Ratios Using Percolation Rests" from Minnesota Rules, Chapter 7080.2150, Subd. 3(E) and herein adopted by reference shall be used to size SSTS infiltration areas.
(C) Compliance criteria for existing SSTS.
(1) SSTS built before April 1,1996 outside of areas designated as shoreland areas, wellhead protection areas, or SSTS providing sewage treatment for food, beverage, or lodging establishments must have at least 2 feet of vertical separation between the bottom of the dispersal system and seasonal saturation or bedrock.
(2) SSTS built after March 31,1996 or SSTS located in a shoreland area, wellhead protection area, or serving a food, beverage, or lodging establishment as defined under Minnesota Rules, 7080.1100, Subd. 84 shall have a 3-foot vertical separation between the bottom soil infiltrative surface and the periodically saturated soil and/or bedrock. Existing systems that have no more than a 15% reduction in this separation distance (a separation distance no less than 30.6 inches) to account for settling of sand or soil, normal variation of separation distance measurements and interpretation of limiting layer characteristics may be considered compliant under this chapter. The vertical separation measurement shall be made outside the area of system influence, but in an area of similar soil.
(D) Holding tanks.
(1) Holding tanks may be allowed for the following applications: as replacements for existing failing SSTS and SSTS that pose an imminent threat to public health or safety on lots with limitations that will not allow for the installation of a Type I SSTS or for uses that are seasonal or intermittent in nature and will not use more than 150 gallons of water per day.
(2) Holding tanks meeting the above-mentioned criteria may be used for structures with limited water use as determined by the Department under the following conditions:
(a) The owner shall install a holding tank in accordance with Minnesota Rules, Chapter 7080.2290.
2015 S-13
(b) An alarm device shall be installed that identifies when the holding tank is at 75% capacity per Minnesota Rules, Chapter 7080.2290 Subd. F.
(c) The owner shall maintain a valid contract with a licensed maintainer to pump and haul the holding tank contents to a licensed treatment facility or an MPCA approved land application site. This requirement is waived if the owner is a farmer who is exempt from licensing under M.S. § 115.56, subd. 2(b)(3).
(d) The holding tank shall be regularly pumped, no less frequently than once a year or other regular schedule approved by the Department based on water use.
(e) The maintainer shall certify each date the tank is pumped, the volume of the liquid waste removed, the treatment facility to or site on which the waste was discharged, and the water meter reading at the time of pumping and report to the Department.
(3) Failure to meet these requirements shall constitute a violation of this Ordinance and will result in enforcement actions being taken by the city per § 153.031 of this chapter which may include, but not be limited to, banning use/occupancy of the structure(s) served by the holding tank(s).
(Ord. 555, passed 7-28-2015)