Compost handling in agriculture systems: Appropriate storage options

Erica Rogers, Sarah Fronczak, and M. Charles Gould<gouldm@msu.edu>, Michigan State University Extension - February 08, 2022

Part three of a six-part series on compost utilization and management on farms.

for decorative purposes only — Compost storage pad. Photo by Charles Gould | Michigan State University Extension

To maximize the improvement of soil health and plant protection that compost’s beneficial microbial population can provide, compost should be applied as soon as it is delivered. However, circumstances may arise where it is necessary to store compost until it can be land-applied.

Because it is sometimes difficult to immediately land-apply compost, Michigan State University Extension recommends locating a proper compost storage site. When choosing a site, minimization of odors and pests, as well as potential environmental implications must be considered. While composted manure is less likely to contaminate crop and water sources than raw manure, the best practice is to cover and store compost as far away as possible from water sources. If composting was not done correctly, the site could attract pests such as flies and scavengers. This can bring about not only the concern of disease, but also the potential for mess and lack of containment. If a proper storage site is not chosen, there is the potential for nuisance complaints from neighboring residents, and potential visits from state regulatory agencies.

Composting is aerobic and requires active management

Nuisance odors can be associated with composting that is not done correctly. For instance, a pile of manure or other organic materials just left sitting to decompose is considered decomposition, not composting. Decomposing is an anaerobic process in which there is a lack of oxygen, whereas composting is an aerobic process that requires adequate oxygen. The introduction of oxygen in a composting system allows for the survival of advantageous microbes that help to breakdown organic components. Without oxygen, these beneficial microbes cannot survive, and will often generate anaerobic microbes that produce an offensive odor.

Other points surrounding odor that must be recognized are neighbor relationships, including the distance to property lines. This can be especially important if those properties are home to non-farm residents. Furthermore, if the compost is not properly managed, it is considered a stockpile. It is important to realize that stockpiles have specific setbacks and regulations that must be followed, so it is very important to make sure compost is sufficiently managed as compost.

Lack of containment and proper location may lead to potential environmental impacts, specifically, to surface waters and groundwater. A few ways to help prevent possible contamination include:

Placing compost on an impermeable surface such as clay ground, cement pad, etc.
Using a covering to keep rainwater off such as a fleece blanket or roofed structure, allowing clean water to stay clean.
If not covering, then a way to contain, collect, or filter leachate from the compost such as a vegetative buffer to filter nutrients allowing for eventual movement of clean water.

In the next article, we will discuss the safe transfer of composted materials. Part four in this series will address compost application.