Environmental Decisions in the Face of Uncertainty

New report from the National Academies Press on decision making under uncertainty.

Description: The U.S. Environmental Protection Agency (EPA) is one of several federal agencies responsible for protecting Americans against significant risks to human health and the environment. As part of that mission, EPA estimates the nature, magnitude, and likelihood of risks to human health and the environment; identifies the potential regulatory actions that will mitigate those risks and protect public health1 and the environment; and uses that information to decide on appropriate regulatory action. Uncertainties, both qualitative and quantitative, in the data and analyses on which these decisions are based enter into the process at each step. As a result, the informed identification and use of the uncertainties inherent in the process is an essential feature of environmental decision making.

EPA requested that the Institute of Medicine (IOM) convene a committee to provide guidance to its decision makers and their partners in states and localities on approaches to managing risk in different contexts when uncertainty is present. It also sought guidance on how information on uncertainty should be presented to help risk managers make sound decisions and to increase transparency in its communications with the public about those decisions. Given that its charge is not limited to human health risk assessment and includes broad questions about managing risks and decision making, in this report the committee examines the analysis of uncertainty in those other areas in addition to human health risks. Environmental Decisions in the Face of Uncertainty explains the statement of task and summarizes the findings of the committee.

Table of Contents

1. Introduction
   
2. Risk Assessment and Uncertainty
   
3. Uncertainty in Technological and Economic Factors in EPA's Decision Making
   
4. Uncertainty and Decision Making: Lessons From Other Public Health Contexts
   
5. Incorporating Uncertainty into Decision Making
   
6. Communication of Uncertainty
   
7. Synthesis and Recommendations
   

• Appendix A--Approaches to Accounting for Uncertainty
  
• Appendix B--Committee Member Biographical Sketches
  
• Appendix C--Meeting Agendas
  

Table 5-1

Type of Uncertainty	Factors Considered in the Decision
	Health Effects Only	Technology Availability	Cost-Benefit
Variability and Heterogeneity	Use of safety or default factors (using statistics) if little or no data on uncertainties are available, and Analysis of statistical distributions, including extreme value analysis if data are available	Using statistics for: Direct assessments, and Technological choice/risk analysis	Using statistics for: Cost-effectiveness analysis Cost-benefit analysis, and Multiattribute utility analysis
Model and Parameter Uncertainty	If little or no data are available, using expert judgments and the use of safety or default factor, and If data are available, using expert elicitation and analysis of probability distributions, including extreme value analysis	Using formal expert elicitation to assess technology availability, and Using expert judgments for technology choice/risk analysis	Using expert judgments for: Cost-effectiveness analysis Cost-benefit analysis, and Decision analysis
Deep Uncertainty	Scenario analysis, and robust decision-making methods

Lots of room for expert judgment. How comforting. I guess I'll have to read the report to figure our what Deep Uncertainty is...