r PROBLEM PREVENTION STRATEGIES LOW TECH APPROACHES TO ~ - - - COMPOSTING SUPERMARKET ORGANICS

M ORE than 6.6 million tons of compostable grocery residuals are disposed of each year in the United States at a cost of $482 million, according to recent estimates bv the Grocerv Industry Commit tee on Sol id Waste . In contrast, supermarkets participating in composting programs report saving upwards of 30 percent on disposal costs. Fullscale organic g r o w debris composting projects in Washington, Maine, Michigan and New Hampshire show the feasibility of using low technology approaches similar to methods for yard trimmings composting. However, for many facilities to successfully implement this approach, a higher level of process management is required. In general, low tech composting relies on windrow turning for aeration, utilizes an uncovered composting area, and limits the use of capital equipment. Physical and chemical characteristics of produce residuals differ significantly from yard trimmings. Overall, produce residuals have a higher nitrogen, moisture, and readily available carbon (sugars, starches and proteins) content than yard trimmings. Consequently, there is a greater potential for odor generation, nuisance animal and insect attraction and leachatelsurface water production when composting organic grocery debris. The nonrecyclable cardboard content of organic grocery debris presents another challenge. Including nonrecyclable cardboard (especially wax coated) as a composting feedstock is a relatively new practice, so there is limited information available. Questions include preprocessing requirements, suitability as a bulking material, rate of decomposition and potential trace metal and organic compound content. In recognition of the potential obstacles to implementing grocery waste composting programs, the Clean Washington Center (a Division of the Washington State Department of Economic Development) commissioned a project to address these issues and