Methods of Environmental Risk Management for Land Contamination Problems: Suggestions for Japan

Abstract

In Japan, the Soil Contamination Countermeasures Act was enacted in 2002. Since then, implementation of the required countermeasures to tackle land contamination in urban areas has improved considerably. However, the pollution of soil on private land may spread undetected. Moreover, contaminated land may be left untreated because ridding soil of contamination is very expensive. Therefore, further countermeasures to reduce the environmental risk of land contamination in urban areas are necessary. This study’s purpose is to suggest methods of environmental risk management for urban land contamination in Japan.

First, we consider sources of contamination, differentiating point sources and nonpoint sources, to evaluate how best to manage the environmental risk of land contamination. The characteristics of these two source types are explained through the concept of transaction costs.

Second, we discuss how Japan has approached land contamination problems and adopted regulations since the period of high economic growth. We also briefly discuss foreign countries’ regulations. We then examine what kinds of typical environmental policy measures are effective in environmental risk management for land contamination.

Finally, we suggest practical methods of environmental risk management for land contamination in urban areas. This requires efficient methods to reduce contamination with low transaction costs. In particular, the costs of monitoring and enforcing to reduce contamination caused by nonpoint sources are high. Therefore, it is important to manage these sources appropriately.