The Shadow of Groundwater: The Tokorozawa Disaster Prevention Well Contamination Incident and Environmental Anxiety in the 1990s (June 1998)

The Shadow of Groundwater: The Tokorozawa Disaster Prevention Well Contamination Incident and Environmental Anxiety in the 1990s (June 1998)

In the late 1990s, Japan faced stagnation after the bursting of the bubble economy, and concerns about the living environment and health were on the rise. Among these, the risks posed by chemical substances attracted considerable attention, and following dioxin and environmental hormones, the safety of groundwater and drinking water was placed at the center of people's concerns. In the midst of all this, the detection of chloroethylene, a known carcinogen, in a disaster prevention well in Tokorozawa City, Saitama Prefecture, sent shockwaves through the community, as well water, which was supposed to be a lifeline in times of disaster, became a symbol of danger. Groundwater contamination originating from former factory sites and industrial wastes has become a reality that threatens the infrastructure of life in urban and suburban areas.

Against the backdrop of this problem, measures were taken in terms of both environmental technology and the legal system. Methods such as activated carbon adsorption, air sparging, soil cleaning, and bioremediation were studied for groundwater purification to strengthen on-site response capabilities. At the same time, the Water Pollution Control Law and Waste Disposal and Public Cleansing Law were revised, and the Environmental Impact Assessment Law came into effect in 1997, establishing a legal framework. Furthermore, the Environment Agency promoted the introduction of the PRTR system, and a system to monitor the release and transfer of chemical substances was being established. The Tokorozawa case provided an opportunity to hasten the institutionalization of the system.

The case encouraged citizens' movements and local governments to tighten regulations, and showed once again that the threat to the safety of water, a familiar resource, directly links environmental problems to daily life. As a result, the case marked a milestone in the intersection of technological innovation, legislation, and public awareness, and was a major step forward for environmental administration in Japan.