This document is available in the Adobe Acrobat PDF Format. The photolysis stage converts organic contaminants into more easily degradable compounds. The rate of photolytic degradation is several times faster with artificial UV light.
Degradation is enhanced by adding surfactants to mobilize the contaminants.
The second step, the biodegradation stage, further destroys the organic contaminants and detoxifies the soil. When sunlight is used, the soil is continually tilled and sprayed with a surfactant. Water may be added to maintain soil moisture. When UV lights are used, parabolic reflectors are suspended over the soil to increase the amount of UV radiation. After photolysis is complete, biodegration is enhanced by adding microorganisms and nutrients and further tilling the soil.