METHOD OF DECONTAMINATING GROUND AND EQUIPMENT THEREFOR

摘要

PROBLEM TO BE SOLVED: To provide a method of decontaminating a ground for effectively preventing contamination from being diffused by a ground water flowing in the ground contaminated by a harmful substance. SOLUTION: A predetermined amount (1.5-2.5 times) of ground water is pumped from a pumping well installed at a downstream side of the contaminated ground and the ground water contaminated by the harmful substance is decontaminated by a harmful substance removal device. Thereafter, the ground water is reduced using a water injection well installed at a downstream side and a flow direction of the ground water is partially directed to a reverse direction or a flow speed of the ground water is extinguished. As a second means, a water injection well is further provided at an upstream side of the pumping well, a required amount of the ground water is pumped and a required amount thereof is decontaminated and is reduced by the water injection well at the downstream side. After a remained pumped ground water is decontaminated by adding a decontaminant for neutralizing and making the harmful substance harmless thereto, the decontaminant is circulated in the ground water by reducing using the water injection well at the uppermost-stream side to neutralize and make a contaminant positioned at an original position harmless.