REMEDIAL METHOD FOR OIL-CONTAMINATED SOIL

摘要

PROBLEM TO BE SOLVED: To provide a method for the remediation of oil-contaminated soil, carrying out bioremediation by which widespread and low-concentration contamination can be treated at low cost by activating indigenous bacteria in contaminated soil, and capable of decomposing even persistent polycyclic aromatic hydrocarbons. SOLUTION: After nitrogen and phosphorous sources in a form of an aqueous solution are added to soil contaminated with aromatic hydrocarbons and saturated aliphatic hydrocarbons, the supply is stopped until the nitrogen content of the soil is reduced to 0.01 g per kg of dry soil and the number of aerobic heterotrophic bacteria per g of the soil expressed in terms of dry soil is reduced to 102 times the initial number or lower. While the supply of the nitrogen and phosphorous sources is stopped, the number of aerobic heterotrophic bacteria per g of the soil expressed in terms of dry soil is once increased to 102 times the initial number or higher.