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Risk and Uncertainty Analysis Procedures for the Evaluation of Environmental Outputs,

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Ecosystem restoration projects are replete with uncertainties, large and small. A major source of uncertainty in many such projects is the environmental output of the project. To estimate existing and future environmental outputs, many U.S. Army Corps of Engineers projects rely on habitat evaluation models like the Habitat Evaluation Procedures REP developed by the U.S. Department of the Interiors Fish and Wildlife Service U.S. Fish and Wildlife Service. REP analysis, as this process is called, relies on the estimation of the number of habitat units that exist at a site under certain environmental conditions. Habitat units are the simple product of a number of acres of habitat and a habitat suitability index that indicates the relative suitability of those acres for a particular wildlife species. The habitat suitability index is based on the mathematical manipulation of a set of habitat variables. A case study is used to illustrate the role that habitat variable measurements play in the uncertainty that attends the estimation of project outputs. The lessons learned during the course of the case study investigation can be grouped into three categories preparation, data collection and analysis. During the preparation of the risk-based analysis several things were learned. First, it is necessary to realize that uncertainty exists, it cannot be eliminated and it is best to address it explicitly. Second, one must understand the nature of uncertainty and how to think about it. Third, the purpose of the risk analysis, to improve decision-making, must be clear to all. Fourth, the major sources of uncertainty must be identified as soon as possible. Fifth, care must be taken to assure that everyone is using the language consistently. Sixth, preparing ahead of time for the risk-based analysis is important.

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  • Operations Research
  • Air Pollution and Control

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