SSTS and MSTS Technical and Compliance Criteria
SSTS and Midsize SSTS (MSTS) are governed by a combination of state regulations, local government unit (LGU) ordinances, and food/beverage/lodging establishment requirements.
The technical criteria and inspection requirements for SSTS are governed by Minn. Rules Chapter 7080; MSTS by Minn. Rules Chapter 7081. How both apply at the local level is detailed in each LGUs ordinance; therefore it’s important you have the most recent copy of the local ordinance.
This page contains links to current Minn. Rules Chapter 7080 and Chapter 7081 regulations, plus links to fact sheets and forms to assist in interpreting and understanding the technical criteria.
SSTS technical criteria (7080.1550 to 7080.2500)
Links under this heading take you to the Minnesota Revisors of Statutes website. 
- Acceptable and Prohibited Discharge
- Design Phase I: Site Evaluation
- Design Phase II
- Sewage Tanks
- Dosing of Effluent
- Final Treatment and Dispersal
- Type I Systems
- Type II Systems
- Type III Systems
- Type IV Systems
- Type V Systems
- Maintenance
- System Abandonment
SSTS compliance criteria and inspections
Links under this heading take you to the Minnesota Revisors of Statutes website.
MSTS technical criteria (7081.011 to 7081.0300)
Links under this heading take you to the Minnesota Revisor of Statutes website.
- Flow Determination
- Infiltration
- Preliminary Evaluation
- Field Evaluation
- Soil Interpretation for System Design
- Site Protection
- Groundwater Investigation
- Design Standards
- Sewage Tanks
- Distribution of Effluent
- Dosing of Effluent
- Final Treatment and Dispersal
- Construction Requirements
- Operation and Maintenance
- System Abandonment
MSTS compliance criteria (7081.0040 to 7081.0080)
Links under this heading take you to the Minnesota Revisor of Statutes website.
- State Regulation
- Federal Regulation
- Local Regulation
- Compliance Criteria for New, Replacement, or Existing Systems
Advanced design guidance
All sizes of Type IV SSTS (systems with advanced treatment), and all SSTS with a flow of 2,501 gallons per day to 10,000 gallons per day need to be designed by an Advanced Design business with some components needing to be designed by AELSLAGID professionals. Below are Prescriptive Standards and Design Guidance that Advanced Designers must follow in designing the above mentioned systems.
Subsurface Sewage Treatment Systems - Prescriptive Designs and Design Guidance for Advanced Designers
- October 2010 Design Guidance Update (wq-wwists4-44b)
- September 2011 Design Guidance Update (wq-wwists4-44c)
- Single Pass Sand Filters - Recommended Standards and Guidance (RSG) Document (wq-wwists4-42)
- Recirculating Sand Filters - Recommended Standards and Guidance (RSG) Document (wq-wwists-41)
Related fact sheets and links
General
- Why Treat Sewage?
- Soil-based Sewage Treatment Systems
- Septic System Additives
- Antibacterial Products in Septic Systems
- High-efficiency Furnaces, Iron Filters, Water Softeners
- Comparison of Plumbing and SSTS Regulations (wq-wwists4-43)
Design
- Policy on Utilizing Artificial Drainage Methods For Subsurface Sewage Treatment Systems
- SSTS Design Worksheets and Forms
- Bedroom Definition for Determining Subsurface Sewage Treatment System Size
- Well Setbacks
- Wells and SSTS Setbacks (wq-wwists4-36)
- Waste Concentrations - U of MN OSTP Manual
- Minnesota NRCS Soil Survey Manuscripts (PDF files of printed soil surveys manuscripts)
- NRCS Soil Data Mart (Official Soils Data)
- NRCS Web Soil Survey (Online Soil Maps)
- Perc Test Procedure
- SSTS and Building Setbacks (wq-wwists4-47)
Compliance inspections
-
Compliance Inspections for SSTS (wq-wwists4-39) - Compliance Inspections Fact Sheet - Existing Systems
- Compliance Inspections Fact Sheet - New or Replacement Systems
- Existing System Inspection Form (wq-wwists4-31)
- Instructions for Compliance Inspection Form (wq-wwists4-31a)
- Septic Tank Maintenance Reporting Form (wq-wwists4-38)
- Guide to Septic System Disclosure at Property Transfer
- Vertical Separation Factsheet
