Minnesota Administrative Rules
Pollution Control Agency
7080 - INDIVIDUAL SUBSURFACE SEWAGE TREATMENT SYSTEMS
7080.1500 - COMPLIANCE CRITERIA.
Subpart 1. Treatment required.
Sewage discharged from a dwelling, group of dwellings, or other establishment that is not served by a system issued a permit by the agency that contains effluent and discharge limits or specific monitoring requirements must be treated according to applicable requirements.Subp. 2. Hand-carried graywater.
Graywater that originated from hand-carried water must not be discharged directly to surface waters, drainageways, or poorly drained soils; in a manner or volume harmful to the environment or public health; or in a manner that creates a public health nuisance as determined by the local unit of government.Subp. 3. Compliance criteria for new construction.
An ISTS regulated under a current construction permit is considered compliant if it meets the applicable requirements of parts 7080.2150 to 7080.2400.Subp. 4. Compliance criteria for existing systems.
To be in compliance, an existing ISTS must meet the provisions of this subpart.
A. The ISTS must be protective of public health and safety. A system that is not protective is considered an imminent threat to public health or safety. At a minimum, a system that is an imminent threat to public health or safety is a system with a discharge of sewage or sewage effluent to the ground surface, drainage systems, ditches, or storm water drains or directly to surface water; systems that cause a reoccurring sewage backup into a dwelling or other establishment; systems with electrical hazards; or sewage tanks with unsecured, damaged, or weak maintenance hole covers. A determination of protectiveness for other conditions must be made by a qualified employee inspector or licensed inspection business.
B. The ISTS must be protective of groundwater. A system that is not protective is considered a system failing to protect groundwater. At a minimum, a system that is failing to protect groundwater is a system that is a seepage pit, cesspool, drywell, leaching pit, or other pit; a system with less than the required vertical separation distance described in items D and E; and a system not abandoned in accordance with part 7080.2500. A determination of the threat to groundwater quality for other conditions must be made by a qualified employee or licensed inspection business.
C. The ISTS must be operated, meet performance standards, and be managed according to its operating permit.
D. ISTS built after March 31, 1996, or in an SWF area as defined under part 7080.1100, subpart 84, must have at least a three-foot vertical separation or a vertical separation in compliance with part 7080.2350, subpart 2, Table XI. The local ordinance is allowed to provide for a reduced vertical separation for existing systems that were designed with at least a three-foot vertical separation distance.
The local ordinance must not allow more than a 15 percent reduction in the vertical separation distance. A 15 percent reduction is only allowed to account for settling of sand or soil, normal variation of measurements, and interpretations of the limiting layer conditions.
E. ISTS built before April 1, 1996, in areas that are not SWF areas as defined under part 7080.1100, subpart 84, must have at least two feet of vertical separation.
F. The vertical separation measurement for items D and E must be measured outside the area of system influence in an area of similar soil.Subp. 5. Compliance criteria for systems with a flow of greater than 2,500 gallons per day.
In addition to the requirements under subpart 4, systems designed under part 7080.2150, subpart 4, must demonstrate that the additional nutrient reduction component required under those items is in place and functioning.Subp. 6. Compliance criteria for systems receiving replacement components.
Components of an existing system that result in the system being in noncompliance must be repaired or replaced according to part 7082.0100, subpart 1. The repaired or replacement components must meet technical standards and criteria for new construction according to local ordinance. The remaining components of the existing system must result in the system being in compliance with subpart 4.Statutory Authority:
MS s 115.03; 115.55History:
32 SR 1347; 35 SR 1353Published Electronically:
October 10, 2013