Environmental systems analysis tools for decision-making : LCA and Swedish waste management as an example

Abstract: Decisions are made based on information of different kinds. Several tools have been developed to facilitate the inclusion of environmental aspects in decision-making on different levels. Which tool to use in a specific decision-making situation depends on the decision context. This thesis discusses the choice between different environmental systems analysis (ESA) tools and suggests that key factors influencing the choice of ESA tool are object of study, impacts considered and information type regarding sitespecificity and according to the DPSIR-framework.Waste management in Sweden is used as an example to illustrate decision-making situations, but discussions concerning choice of tools are also thought to be of general concern. It is suggested that there is a need for a number of ESA tools in waste management decision-making. Procedural tools like Environmental Impact Assessment (EIA) and Strategic Environmental Assessment (SEA) should be used e.g. by companies applying for development of waste management facilities and by public authorities preparing plans and programmes. Within these procedural tools analytical tools providing relevant information could be used, e.g. Risk Assessment (RA), Life Cycle Assessment (LCA) or Substance Flow Analysis (SFA). Analytical tools may also be used separately. If the decision-making situation concerns a choice between different waste management options, such as recycling, incineration and landfilling, environmental aspects could be assessed using LCA or Material Input Per unit Service (MIPS). To study certain substances within the waste system, RA or SFA could be used.An LCA of different strategies for treatment of municipal solid waste was made. A conclusion from this study is that the waste hierarchy is valid as a rule of thumb. Suggestions resulting from this study are that decisions promoting recycling of paper and plastics should be pursued, preferably in combination with decisions promoting the use of plastics replacing plastics made from virgin sources. The study further identifies a need for limiting transportation by private car for options requiring source separation of waste. When recycling is not an alternative, incineration is in general preferable to landfilling. Key issues that may affect the ranking of the waste treatment options include alternative energy sources, the material the recycled material replaces and the time perspective chosen.It is suggested that LCA may be a useful tool in waste management, both on its own and as a part of an SEA. Results from LCAs can provide advice on ranking of alternatives. More importantly, key assumptions and value choices that may influence the rankings can be highlighted and thus made clear to the decision-makers. In general, LCA results are not site-specific and provide information in the form of potential environmental impacts, and thus could be combined with other tools if other type of information is needed.