In March 1969, companies that were scheduled to set up operations in the Petrochemical Complex No. 3 concluded an agreement with Yokkaichi City to work towards preventing environmental pollution.
The terms of the agreement included proactive implementation of environmental pollution prevention measures, temporary stoppage of operations in the event of an environmental pollution, and the right to examine the plants on-the-spot by the relevant authorities. A committee including local residents was also set up to ensure smooth implementation of the agreement.
Companies in the area actively engaged in measures to prevent pollution, and the agreement was later extended to include the No. 1 and No. 2 petrochemical complexes.