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The MPCA encourages the beneficial reuse of biosolids in a manner that protects human health and the environment. The treatment of domestic wastewater can generate biosolids. The treatment of these solids produces a nutrient-rich organic material that farmers can use. Various wastewater treatment processes stabilize and disinfect the solids, destroying harmful bacteria and reducing odors. The result is a humus-like organic matter, dry powder, pellets, slurry, or liquid that bears little resemblance to the untreated solids from which it was derived. Biosolid recycling reduces both the amount of waste going to landfills and incinerators and the total use of petroleum-based chemical fertilizers.

State and federal rules govern the use and disposal of biosolids, set limits for contaminants such as metals, and require pathogen and vector attraction reduction, site and crop harvesting restrictions, and record keeping and reporting. Biosolids that will be applied to land must meet strict regulations and quality standards.

Permitting biosolids activities

Biosolids activities are authorized though NPDES/SDS or SDS permits. Types of facilities listed below that manage biosolids should have a biosolids section in their NPDES/SDS or SDS permit or apply for an SDS permit using application forms located on the MPCA Wastewater permit forms webpage: 

  • municipalities with mechanical treatment
  • large subsurface treatment systems that are publicly owned
  • a large subsurface treatment system that has a mechanical component like denitrification
  • private entities that provide biosolids treatment services to domestic wastewater treatment facilities throughout the state of Minnesota

Domestic wastewater facilities planning to decommission or clean out their ponds may add a biosolids section to their NPDES/SDS permit, but it is not required. Permittees who are relining a wastewater pond must apply for a permit modification to include a construction schedule. All of these activities require a permittee to follow this guidance for decommissioning and relining:

Staying in compliance

Forms and reporting requirements you'll need to maintain compliance with biosolids regulations.

Site application forms

Submit these forms to the MPCA for approval prior to land-applying biosolids;

Annual reports

State of Minnesota (MPCA)

The biosolids annual report is due December 31 of each year. This report must be submitted even if no biosolids were land applied during a cropping year. A cropping year runs from Sept. 1 through Aug. 31.

PFAS biosolids analysis is required once per cropping year. Biosolids must be sampled, analyzed, and the results reported to the MPCA before the first land application event of each cropping year.

Federal (U.S. EPA)

Federal annual reports are due by February 19 each year. Any facility described below must submit reports:

  • Class 1 management facilities (EPA Title 40, Chapter I, Subchapter O, Part 501.2)
  • facilities with a design flow rate of greater than 1 million gallons per day
  • publicly owned treatment works that serve a population of 10,000 people or more

For more information about federal reporting review the following links:

Resources

Land application

Biosolids PFAS

Federal