### History of Waste Disposal - Kagawa Prefecture - April 2007 - 2020s

### History of Waste Disposal - Kagawa Prefecture - April 2007 - 2020s

#### 2007: Technology Development and Introduction
In 2007, Ikeda Construction Industry Co. in Kagawa Prefecture developed a technology to solidify and improve the treatment of dredged mud generated at construction sites. This technology enables approximately 10,000 tons of dredged soil to be reused annually as roadbed material and other construction materials, reducing costs by about 30% compared to conventional treatment methods. The project also succeeded in reducing carbon dioxide emissions, and attracted attention as a model case for recycling construction waste generated in Kagawa Prefecture. The technology is now being deployed throughout the region, and the project has received high praise from local governments and the construction industry.

#### 2010s: Expanding the Scope of Application
In the 2010s, the scope of application of this technology expanded throughout Kagawa Prefecture. Ikeda Kensetsu Kogyo worked with local municipalities to promote the use of this technology at harbors and river dredging sites. In addition, the gypsum-based soil stabilizer was improved, further enhancing processing efficiency. During this period, the amount of dredged soil reused in Kagawa Prefecture reached approximately 12,000 tons per year, which was widely used in public and private construction projects in the prefecture. Furthermore, the stabilization of the quality of the improved soil has led to its use in a wide variety of applications, including road construction and levee reinforcement projects.

#### 2020s: Technological Evolution and Development
In the 2020s, Ikeda Kensetsu Kogyo introduced new high-density thin-layer dredgers and pump vessels to improve the efficiency of dredging operations. The use of gypsum-based soil improvement and solidification materials enabled homogeneous improvement of dredged mud, enabling immediate removal and early reuse. With this technology, more than 10,000 tons of muddy soil is recycled annually, simultaneously reducing processing costs and environmental impact. In addition, Kagawa Prefecture has established "Kagawa Prefecture Construction Waste Recycling Guidelines" and is promoting Ikeda's technology throughout the prefecture.

#### Future Prospects
In Kagawa Prefecture, further technological innovation and the expansion of recycling within the region are expected. Ikeda Kensetsu Kogyo plans to develop new construction materials using improved soil, and has plans to increase its annual processing volume to 15,000 tons in the future. This initiative will continue to attract nationwide attention as an advanced model case for the realization of a sustainable society.