What are EQ Biosolids?

EQ Biosolids are a product of wastewater treatment that supplies organic matter and improves the structure and porosity of soils, which allows plants to more effectively utilize nutrients. Air-dried biosolids can be used as a soil amendment or conditioner for establishing turfgrass and for mixing into custom topsoil blends.

EQ Biosolids look and feel like dark, fine-textured topsoil. They can be used on turfgrass at golf courses, athletic fields, parks and other recreational areas, and for restoration of brownfields and other disturbed lands. Better soil and healthier plants require less maintenance and make for more robust and durable landscaping.

EQ Biosolids meet the USEPA’s 40 CFR Part 503 requirements for exceptional quality (EQ), which are based on comprehensive risk assessments that are protective of human health and the environment. The regulations establish levels of trace metals and pathogens that are based on scenarios of a person coming into contact with biosolids or food grown on land receiving biosolids. These scenarios include children ingesting biosolids, workers breathing dust while applying biosolids, and homeowners using biosolids in their vegetable gardens.

The Metropolitan Water Reclamation District of Greater Chicago (MWRD) has an exemplary biosolids management program. EQ Biosolids go through an extensive testing regimen to ensure each batch is of the highest quality. The MWRD has been successfully using EQ Biosolids on golf courses and athletic fields at both public parks and schools in the Chicago area for more than 20 years.

State law prohibits the application of EQ Biosolids on snow-covered or frozen ground. Additionally, EQ Biosolids must be applied in a manner that follows recommended application rates when used on agricultural land, and must be applied in a manner that follows best management practices to protect water quality when used on all other land.

Regulatory Development- In 2015, Illinois Governor Bruce Rauner signed legislation (Public Act 99-0067) that amended the Illinois Environmental Protection Act to recognize biosolids as a safe, beneficial and renewable resource that should be used locally. This legislative amendment also allows composted biosolids to be available to the public.

How To Use EQ Biosolids

        Athletic Fields- Topdress athletic fields and other turfgrass areas.

       Topsoil Blending- Blend 25-50 percent uniformly with topsoil and spread as needed for establishing           turfgrass and landscaping.

Benefits of using biosolids Include: 

  •  Increased infiltration and water holding capacity
  •  Longer retention of nutrients for better uptake by plants
  •  Improved topsoil structure and porosity for a better plant root environment

EQ Biosolids Analysis*

Parameter Units Range EPA EQ Metal Limits Parameter Units Range EPA EQ Metal Limits
pH   5.8-6.7   Hg mg/kg 0.69-0.92 17
Dry Matter % 60-73   Ni mg/kg 26-51 420
As mg/kg 6.0-8.0 41 Pb mg/kg 81-120 300
Cd mg/kg 2.0-8.0 39 Se mg/kg <5 100
Cu mg/kg 330-493 1,500 Zn mg/kg 976-1,237 2,800
*Please see the EQ Biosolids Safety Data Sheet for more information 

Ordering EQ Biosolids 

EQ Biosolids Current Applications 

Maggie Daley Park
EQ Biosolids were used to help transform the roof of an underground parking garage into Maggie Daley Park, a lushly landscaped park and playground in downtown Chicago. The landscape contractor used EQ Biosolids in a blend to make nearly 12,000 cubic yards of custom topsoil. The grass and landscaping is flourishing in spite of heavy use and the park is a popular destination for residents and tourists.

Related Information

PFAS - Per- and Polyfluoroalkyl Substances

PFAS By numbers - Source: CASA

Analytical Results for PFAS in 2019 Total Diet Study Sampling (Parts Per Trillion)—Dataset 1 (fda.gov)

Uptake of Perfluoroalkyl Acids into Edible Crops Grown in Biosolids-Amended Soil 

Environmental Management System

EQ Biosolids Safety Data Sheet


Fact Sheet: Biosolids and COVID-19   (Español) - May 12, 2020

Biosolids/Compost Windy City Newsletters