Through a method called sparging, the air is blown into the ground and rises as bubbles to the surface where it releases pollutants. Another way is to pump and treat groundwater and filter it through biological or chemical means.
Microorganisms are introduced into the ground in an action called inoculation, which degenerates the harmful contaminants.
Pollutant molecules are broken up with liquid or gas chemical oxidation processes. Chemical precipitation, ion exchange, and carbon absorption remove heavy metals from the groundwater.