Memories of the Earth: Progress and Current Status of Soil Contamination Countermeasures in Japan (2003-2023)

Memories of the Earth: Progress and Current Status of Soil Contamination Countermeasures in Japan (2003-2023)

Soil contamination countermeasures in Japan began in earnest with the enactment of the Soil Contamination Countermeasures Law in 2003. This made surveys mandatory at the time of land conversion, and especially in Shiga Prefecture, low-cost surveys utilizing simple diagnostic technology from the U.S. became widespread. Mitsubishi Material Resources Development Corporation and Mitsui Real Estate Sales Co., Ltd. also strengthened their real estate surveys, and the market expanded. 2005 saw the introduction of an impairment accounting system, which required risk assessment of land prices.

In the 2020s, the number of surveys increased due to stricter environmental regulations and increased corporate awareness; in 2021, 1,415 soil surveys were conducted, and many trichloroethylene, lead, and fluorine were detected as contaminants. The impact of industrial activities continues in Tokyo and Osaka Prefecture, and soil risk assessment associated with redevelopment is also becoming more important in Shiga Prefecture.

Going forward, measures must be strengthened to achieve the SDGs, and the Ministry of the Environment and local governments are using subsidy programs to support companies in introducing remediation technologies. More efficient decontamination is expected through the latest technological developments.