Citizens in Bavaria, Germany's largest state, take drop-off centers for granted. For their convenience, the state has established a network of unmanned drop-off centers, called "container islands," as part of its multifaceted system for recyclables collection.
Since 1992, more than half of the municipalities had a container island to collect at least three materials, according to a 1994 study by the Bavarian State Ministry for Development and Environmental Issues. The study offers tips on how to plan and operate effective drop-off centers.
The most popular container system combination in Bavaria is for glass, metal and textiles. On average, each of the state's 11.2 million citizens delivers 32 kilograms of used glass, 2.8 kilograms of tinplate (predominantly cans, sometimes with aluminum included) and 2.2 kilograms of textiles to these centers annually.
In communities that rely on containers for collecting paper products, the average drop-off rate is 50 kilograms per person per year. Materials that are more difficult to sort or collect, such as plastics, typically are taken to staffed drop-off centers.
More than 30 German companies, in addition to other European manufacturers, offer container systems on the German market, giving the communities a wide variety of choices (see figure). Forms include igloo, cube, honeycomb and disk shapes; sizes range from 0.8 to 4.5 cubic meters.
Typically, the containers are made of galvanized or painted steel or plastic reinforced with glass, flax or jute fibers. Recyclable containers with natural fibers also are gaining popularity. Other options include flame-retardant coatings for plastic containers, reinforced sides and corners as well as rubber profiles or other means of noise suppression.
Standard containers are emptied by crane or through lockable side openings or can be wheeled away when full. Those equipped for crane emptying are preferred in Bavaria, partly due to their space-saving features.
Specialized containers also are available, such as small boxes that are designated for household batteries and can be attached to the front of recovered metal containers. These are being phased out, however, in favor of collection through retail outlets, mobile programs and staffed drop-off centers.
Since 1993, the Dual System Deutschland (DSD) has been responsible for collecting used packaging materials. To minimize disruption to the existing collection system, the network of drop-off centers was largely retained, while new Dual System Deutschland collection methods were added as needed and meshed with the in-place system. Contracts between the communities and the DSD ensure cooperation for financing, public education and site maintenance.
A perpetual challenge at container islands is balancing quantity and quality. From 1986 to 1991, a pilot program tested fully automatic, battery-powered optical sorting to separate glass by color and to remove impurities. Because of sensitivity to temperature fluctuations and a general tendency for breakdowns, the system was abandoned in favor of manual separation into separate, labeled containers or compartments. Similarly, containers with compaction and size reduction equipment proved to be unsuitable.
When selecting a container island site, according to the Bavarian study, communities should consider the following factors: convenience for residents, the catchment area, collection network density, the availability of public versus private land, zoning restrictions, size and the configuration of the drop-off center, proximity to hospitals and parks, noise protection, impact on services such as telephone booths and utility right-of-ways, available parking, traffic safety and maneuverability of collection vehicles.
Other important considerations in Germany are compatibility with historic landmarks and protection of existing trees.
The study stresses that success hinges upon winning public acceptance and voluntary, responsive participation by making centers both functional and optically pleasing.
Other crucial elements, aside from container and site selection, include container placement and accessibility as well as site screening, safety and upkeep. For example, communities should avoid chaotic-looking, littered drop-off centers and refrain from unpopular surveillance tactics such as video taping to apprehend offenders.
The study concludes with some general recommendations. Communities should limit the number of materials collected at the container islands, even if waste management calls for further diversification; expansion should occur only after adequate testing.
The Bavarian study also recommends upgrading the container island's image based on the motto "beautiful doesn't have to mean expensive." Planning solutions should be practical and aim for simplicity.
Despite anticipated changes in production, communication and recycling as the turn of the millennium approaches, the container island is not likely to be displaced soon by other methods of collecting used materials from the public.