Bioremediation is a treatment process that uses the metabolic activity of microorganisms (bacteria and fungi) to naturally degrade organic contaminants in the soil.

Ex-situ bio-remediation systems, identical in theory to the treatment of in-situ soil, is only different in that the soil is first removed from its native location and placed in organized remediation farms. It is in these farms where these micro-organisms are injected and maintained to degrade organic activity.

Treatment can be enhanced and its efficiency accelerated by the addition of nutrients, oxygen and water to the soil, by manipulating the temperature and pH of the soil, or by combining the process with a soil vapor extraction system.

Bioremediation is particularly effective in treating petroleum hydrocarbons, volatile organic compounds, and in some cases, even chlorinated solvents.