April 26, 2007 | General

Managing Organic Residues In A South Pacific City (The Solomon Islands)

BioCycle April 2007, Vol. 48, No. 4, p. 59
Waste materials from the city’s open market are shredded, then placed in a frame where water is added, removed and feedstock is composted.
Luis. F. Diaz

TO MANY, the South Pacific islands evoke thoughts of white sand beaches, crystal clear water and sun. To others, some of the South Pacific islands bring back sad memories of World War II.
The Solomon Islands (the Solomons) are a chain of islands in the South Pacific between latitudes 5 and 12 degrees south of the equator. The country is located southeast of Papua New Guinea and about 1,000 miles northeast of the Australian Great Barrier Reef.
Total land area of the Solomons is about 28,450 km2 and is subdivided into nine provinces: Central, Choiseul, Guadalcanal, Isabel, Makira, Malaita, Rennell and Bellona, Western, and Temotu. The terrain consists of mostly rugged mountains with some low coral atolls. The country has a wet tropical climate; wet and dry seasons are poorly defined. The total amount of precipitation averages about 260 mm per year.
Population of the Solomon Islands has been estimated in July 2006 at 533,672. The majority of the population is Melanesian. However, there is a sizeable indigenous Polynesian population.
The capital of the Solomon Islands is Honiara, a city located in one of the driest areas of the north coast of Guadalcanal Province. Honiara was the site of a relatively large American military base during World War II. Some of the fiercest fighting took place in the Solomon Islands campaign between 1942 and 1945 which includes the well-known battle of Guadalcanal. The population of Honiara has been estimated at more than 60,000 in 2006.
The Honiara City Council (HCC) currently is emphasizing resource recovery and recycling. As part of this program, the council collects organic wastes from the city’s main open market and transports it to an area for processing. The processing is carried out by the “Custom Garden Association”. Employees of Custom Gardens shred the wastes with the use of a small shredder (Figure 1). The shredded wastes are then placed inside a cylindrical frame made out of a reinforcing bar and a wire mesh. A view of the cylinders is shown in Figure 2.
The frame and its contents are placed longitudinally on the ground and water is added to the mass with a hose as needed. The frame is manually rotated along the ground every day. The cylindrical frames have been made with financial assistance from the HCC. Each frame costs about 2,000 SB dollars (about 300 USD). Small composting units suitable for home composting are made out of plastic barrels which are perforated to allow aeration of the material.
Material is removed from the frames after about 30 days and placed in small piles to cure for an additional 30 days. At the completion of the curing phase, the material is considered ready for use.
The finished compost is either sold to farmers for about 3 USD/10 lb bag or taken to a demonstration garden managed by Custom Gardens where a variety of vegetables are grown. Custom Gardens is a charitable organization supported by the Australian Agency for International Development (AusAID) and the European Union. The Custom Garden Association also operates a Farmer Demonstration Facility on the same site aimed at training farmers how to properly feed their poultry.
HCC is planning on assisting Custom Gardens in the construction of additional composting units to increase the production of compost from market wastes generated in the Honiara area.
Luis F. Diaz is with CalRecovery, Inc., based in Concord, California.

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