Software weighs municipal waste options

The U.S. Environmental Protection Agency (EPA) and the U.S. Department of Energy have signed a three-year cooperative agreement with the Research Triangle Institute (RTI), Research Triangle Park, N.C., to develop a computer model to help local municipal officials evaluate the environmental and economic impacts of different options for managing municipal solid wastes (MSW) in their communities.

In an effort to conserve landfill space and protect the environment, many communities run extensive recycling programs. Specific wastes, such as tires and yard wastes, have been banned from landfills in many areas, and new legislation dictates how nonhazardous commercial waste can be handled. Although well-intentioned, it is not always clear that these efforts result in resource conservation. The recycling process itself consumes energy resources and generates its own set of waste products.

The computer model will use life-cycle concepts to assess different waste management options in terms of collection, transport, processing/recycling, disposal and remanufacturing. Included will be data on energy consumption, costs and environmental releases from using recovered and virgin materials. The system will provide MSW managers a means of evaluating a variety of alternative disposal options.

“This research is an effort to provide policy-makers with a tool that will enable them to make more informed decisions regarding their waste management options,” says Susan Thorneloe, project officer with EPA’s Air and Energy Engineering Research Laboratory. “We want to provide a model that will give state and local decision makers credible data for use on their specific community sites.”

Management professionals are often forced to make decisions about waste management strategies without being able to look at the strategies in the context of the entire MSW system and factor in site-specific information regarding available markets, transportation and environmental and energy impacts.

As communities struggle to develop better strategies for integrated waste management to meet federal, state and local goals, recent regulations for landfilling and combustion of waste have resulted in increased protection of human health and the environment.

In addition, waste management costs have increased, and there is increased interest in more efficient management of waste. A decision support tool is one way to combat the numerous difficulties in MSW and to provide data and a methodology in applying life-cycle principles for evaluating integrated waste management strategies.

The major effort with developing a life-cycle inventory is collecting data for conducting material and energy balance calculations. The first two years of the project will consist of collecting the data from public and field sources, verifying it and then translating it to a mathematical formula. The model, designed to run on a personal computer and based on a Microsoft Windows program, will be completed in the third year.

Several recently completed studies are being reviewed for available data and information, including: The Role of Recycling in Integrated Solid Waste Management to the Year 2000 (Keep America Beautiful, 1994), Mandated Recycling Rates: Impacts of Energy Consumption and MSW Volume (ANL, 1993) and Data Summary of Municipal Solid Waste Management Alternatives (SRI, 1992).

The database of the LCI will be the ultimate product of the research. A user-friendly decision support tool will assist state and local solid waste management personnel in evaluating the economics, energy and resource consumption and environmental releases associated with alternate integrated solid waste management strategies.

The database will also allow the user to analyze a particular solid waste management system and evaluate more efficient alternatives.