## Column

## Past initiatives

Prompted by the oil crises in the 1970s, pioneering initiatives such as recycling were started in many parts of Japan.

## (1) Urban-Rural Environmental Connections Plan (URECs Plan)

In 1980, Toyohashi City started mandating its residents to separate their household garbage into five categories in order to facilitate the effective use of waste. In the same year, the following five plants were built on a single site to enable the integrated treatment of waste: (i) a waste incineration plant, (ii) a composting plant, (iii) a sorting and crushing plant, (iv) a chicken feces drying plant, and (v) a night soil disposal plant. The heat generated from the incineration of combustible waste and residues from the composting plant was used for heating in an adjacent greenhouse complex and for generating electricity for the internal facilities. The overall plan also involved the production of compost from combustible waste and night soil disposal sludge for use by local farmers to fertilize their farmland.

However, the usage of plastic by local residents increased year after year, eventually making it impossible to produce good-quality compost from combustible waste. Although Toyohashi was therefore unable to accomplish the plan’s original goals, its attempt to construct a mechanism in which urban waste is used on rural farms while the food produced in rural farms is supplied to urban communities, in return, had something in common with today’s concept of constructing a recycling loop under the Food Waste Recycling Law, and can be regarded as a pioneering attempt to establish SMC blocks.

## (2) Stardust 80 Plan

In 1973-1980, to cope with the problems of urban waste disposal and the exhaustion of natural resources, the then Agency of Industrial Science and Technology, part of the Ministry of International Trade and Industry, working in cooperation with the Yokohama City Government, constructed and operated a research/demonstration plant for a resource recycling system centered on material recovery. In this system, mixed waste was divided into three groups: (i) garbage, glass and rubble, (ii) paper, and (iii) plastic and metal, so that resources could be recovered from each group by using (i) fast composting equipment, (ii) purifying and pulping equipment, and (iii) thermal decomposition and gasification equipment. However, limitations in the capability of the machine sorting stage for mixed waste prevented the production of good-quality compost and pulp and increased costs. Although the system did not, therefore, come into general use, the project raised awareness of the importance of sorting by waste generators and contributed to the improvement of more appropriate technologies, including those for waste gasification.

## (3) Vacuum transport system for waste

Garbage is usually collected by a sanitation truck, but this method involves problems such as foul odors and pests released from the exposed garbage, and the mess made on the streets. To counter such problems and to meet the growing needs of the public for a better living environment and amenities, some municipalities constructed a system that combined waste incineration facilities and vacuum transport pipelines for the waste.

This system provided benefits such as (i) allowing citizens to throw away garbage whenever they liked, (ii) preventing odors and therefore improving sanitation, (iii) not marrying the street appearance, and (iv) requiring less labor for waste collection and transport. However, it also had disadvantages such as the need for huge initial investments, long transport distance, a lack of flexibility, and the fact that it made people less motivated to reduce waste because of the “invisibility” of the waste. This attempt served as an unsuccessful example from which the 21st century, “the century of the environment,” can learn a great deal on how to plan and implement more eco-friendly approaches such as