This document discusses bioremediation techniques for cleaning up contaminated soils. It defines bioremediation as using microorganisms, fungi or plants to restore a natural environment impacted by pollution. Methods include stimulating indigenous bacteria to break down oil spills or other contaminants, and augmenting soils with bacteria to degrade pollutants. Bioremediation can occur in situ or ex situ and examples provided are bioventing and phytoremediation using plants to extract heavy metals. The advantages highlighted are lower costs than traditional methods while preserving the natural environment.