The use of complex
mathematical models is central to the U.S. Environmental Protection Agencys
(EPAs) decision-making process. It is generally impractical to obtain
measured data to support the many scenarios involved in environmental decision-making.
Thus, EPA relies heavily upon models for a host of applications, including estimating
the behavior of chemical substances released into the environment.
Because of the
strategic role that models play in environmental decision-making, EPA and other
regulatory bodies recognize the critical importance of employing best practices
for the selection, assessment, and use of environmental models. The need for
clear and objective criteria in these areas has become all the more essential
with the passage of the Information Quality Act (IQA) in 2000.
This Washington Watch column outlines the reasons why models are so much a part of the environmental decision-making process, how models can be used and abused, and what EPA is doing to ensure that models are created and used in ways that are legally and scientifically defensible.