Bio-Remediation Bio-remediation involves utilizing the natural process of biological degradation to reduce and eventually eliminate concentration of its contaminents remaining in the soil. In-stu bio-remediation consists of the direct application of engineered petroleum-degrading, non-indigenous, bacterium cultures to the impacted soils. The microbial populations use the hydrocarbons as food, converting the containment to carbon dioxide (Co2), water (h2o) and simple proteins. This choice of remediation may take place over a longer time frame than other possibilities; however, bio-remediation is more cost effective. Although the exact time frame is difficult to predict, one to three years is usually adequate to reduce petroleum hydrocarbon concentration to M.O.E. guidelines, These bacteria are as effective as excavation and removal and eventually eliminate all concentrations remaining in the soil.