Composting is becoming increasingly popular, whether it occurs in a compost bin in the backyard or in windrows lined up at a large-scale compost operation. Residential composting by a homeowner provides an easy alternative to throwing away food scraps and yard waste; simply place them in a small pile or bin. For those interested in learning about residential composting and setting up their own compost bin, review the department's Homeowners’ Composting Guide - PUB0183 fact sheet.

Rows of composting materials waiting to be composted.
Rows of composting materials waiting to be composted.

Large-scale composting facilities often provide a welcome service to their communities by providing a point of collection for leaves, grass clippings, yard and garden debris and brush, tree and other yard waste. Co-composting facility operations combine some or all of the same composting facility materials, along with additional feed stocks like food waste and animal manures. These facilities can provide their communities with a processed end-product that helps protect the soil from erosion, keeps the soil moist and adds organic matter to the soil. For more information about composting and co-composting, visit U.S. Environmental Protection Agency's Reducing the Impact of Wasted Food by Feeding the Soil and Composting.

Operating a compost or co-composting facility or site must be carefully planned and diligently operated so it does not negatively impact individuals occupying neighboring properties or the environment. The Missouri Solid Waste Management Law and regulations allow compost facilities to operate with an exemption from meeting some of the legal requirements, once initial conditions are met and an approval of operations has been granted. The information provided below is written to guide those interested in establishing and operating a composting/ co-composting facility or site so that a permit exemption may be granted. To learn about other activities that may be exempt from permitting requirements, visit Activities Potentially Exempt from Solid Waste Regulations.

Although farmers that compost or co-compost their own organic wastes may conduct these activities without any permit, or even a permit exemption approval under the Missouri Solid Waste Management Law and regulations, they must still meet regulatory requirements under the Missouri Clean Water Law. Farmers should coordinate composting or co-composting operations with the department's Water Protection Program

Step 1:  Stormwater and Wastewater Management 

For all composting operations, the first consideration in the planning process is to determine the regulatory requirements for stormwater and wastewater management. Questions about determining how the facility should be designed and located on the property to ensure it complies with the Missouri Clean Water Law should be directed to the department’s Water Protection Program. Be prepared to discuss the following information about the facility with the department and be able to provide additional information about the following aspects of the proposed composting or co-composting facility. At a minimum, be prepared to answer the following questions: 

  • What types of materials are going to be composted? Will it be only yard waste, or will the facility co-compost yard waste with other types, such as food waste?
  • How much material will be composted and stored on-site? What is the estimated number of tons of each type of material to be composted per day, week or month? 
  • What are or will be the source(s) of the materials to be composted? Are the sources of these materials sustainable?
  • What method will be used to process the compost materials into the desired end product?
  • What will be produced after the composting process is complete and how will the new product be used?
  • What is the address and county where the compost operation will be located?

Step 2:  Solid Waste Processing Facility Permit Exemption

Once the site's stormwater and wastewater needs are determined, the next step is to contact the department's Waste Management Program to determine if the composting or co-composting operation must have a solid waste processing facility permit. Department staff will discuss the proposed site design and operation with the prospective owner and operator, review documentation about the proposed facility and ensure the stormwater and wastewater management requirements are addressed. The department will also provide additional guidance to ensure the compost facility or site operates in compliance with the Missouri Solid Waste Management Law and regulations. Based on the information provided, the department's Waste Management Program will determine if the planned operation requires a permit. The department's Waste Management Program will follow-up with the prospective owner and operator to get any additional information to obtain a permit or permit exemption approval.

The department has some general guidelines to assist prospective compost facility owners and operators in obtaining a permit or receiving a permit exemption. The department's Waste Management Program will guide prospective owners and operators through this process and continue to help as needed throughout the design, construction and start-up of the composting or co-composting operation.

Step 3:  Changes to the Site or Facility 

Piles of finished mulch separated by large concrete block dividers.
Finished mulch ready to be applied to landscaping.

Once the facility or site is constructed and operating, department staff will still need to periodically inspect, discuss compost operations and review any proposed changes with the composting facility owner and operator. Examples of some changes that may be made to the sites and require input from the department include expanding the site’s processes to increase capacity or improve efficiency, improving operational processes or changing the type(s) of waste materials accepted for processing. The department must approve these changes before they are implemented at the site to ensure the operation remains in compliance with regulatory requirements if the changes are made. By doing this, both the department and the composting or co-composting facility owner and operator will ensure the facility provides goods and services to the surrounding communities for many years, without negatively impacting neighboring properties, public health or the environment.