Soil Amendments
Why is soil health important?
All components of an ecosystem are dependent on viable and healthy soils for the system to function properly. Increased acidity, the presence of heavy metals and other contaminants, and high concentrations of salts can render a soil infertile by inhibiting plant growth, limiting microbial activity, and altering its physical properties. Therefore, it is critical to revitalize soil health in order to restore a degraded ecosystem. In many cases, adding soil amendments such as compost, manure, or lime can revitalize soil by adjusting pH, addressing chemical imbalances, and improving soil texture and structure.
What are soil amendments?
Some treatments involve adding soil amendments to the contaminated media. Soil amendments are materials added to soils in order to revitalize and make them suitable for sustaining plant life or development. Superfund sites and other sites with contaminated or disturbed soils exhibit a variety of problems that often can be addressed effectively and directly through the use of soil amendments. Project managers could evaluate their effects in the subsurface, their potential for eventual transport to surface waters, and their possible subsequent adverse effects on plant and animal communities.
Compost and biosolids are among the most commonly used soil amendments. Other amendments include manure, digestates, sludges, yard waste, and ethanol production by-products. Inorganic amendments include lime, wood ash, coal combustion products, foundry sands, steel slag, dredged materials, and water treatment residuals.
For additional information on soil amendments, please visit the EPA publication The Use of Soil Amendments for Remediation, Revitalization, and Reuse.
What is compost?
Compost is organic material produced by aerobic (utilizing oxygen) decomposition of organic materials such as yard trimmings, food scraps, and manures. Mature compost is frequently used as a soil amendment because it is rich in nutrients, stable, and safe to use near water sources.
Composting is used frequently to significantly reduce pathogens in organic waste streams, since the process generates temperatures hot enough to achieve this reduction. Compost availability and composition varies widely, but in general, compost is generated in much smaller volumes nationally than manures or biosolids.
For more information on compost and how to create your own composting pile, please visit the EPA Composting and Organic Materials Management Pages:
What are biosolids?
Biosolids are the nutrient-rich organic materials resulting from the treatment of sewage sludge (the name for the solid, semi-solid or liquid untreated residue generated during the treatment of domestic sewage in a treatment facility). When treated and processed, sewage sludge can be safely recycled and used as a soil amendment. These biosolids can help maintain productive soils and stimulate plant growth in a sustainable fashion. However, only biosolids that meet stringent Federal and state standards can be approved for use as soil amendments. Now, through a Voluntary Environmental Management System developed by the National Biosolids Partnership (NBP), community-friendly practices also will be followed.
EPA provides the public with educational information, based on the best science, about the safe recycling and disposal of biosolids. To access this information, please visit the EPA Office of Wastewater Management Biosolids web page:
Biosolids Recycling: Restore, Reclaim, Remediate
Film by the EPA Environmental Response Team that outlines the use of biosolids as a remediation tool for contaminated lands and former mining sites.
Further Information and Resources:
- The Use of Soil Amendments for Remediation, Revitalization, and Reuse. (Download 1.74MB PDF)
- Jump-Starting Ecological Restoration - Soil Health U.S. EPA. 2006.
- Soil Remediation, Revitalization, and Reuse: Technical Performance Measures
- Soil Amendments for Remediation, Revitalization, and Reuse Tools: Fact Sheet (Published 2007)
(Download 2.26MB PDF)
This fact sheet describes two tools developed by U.S. EPA in cooperation with 18 federal and local government, academic, and private sector experts. These tools–a white paper titled "The Use of Soil Amendments for Remediation, Revitalization, and Reuse" and an Internet website and search engine titled "Soil Remediation, Revitalization, and Reuse: Technical Performance Measures"–are designed to encourage and assist site cleanup managers to use soil amendments for remediation, revitalization, and reuse of their sites resulted from this collaboration.
