Chapter 2
Assessing Environmental
Impact
Environmental engineering requires that the impact and interaction of engineered struc-
tures on and with the natural environment be considered in any project. In 1970 this
principle was enacted into federal law in the United States. The National Environ-
mental Policy Act (NEPA) requires that environmental impact be assessed whenever
a federal action will have an environmental impact, as well as requiring that alterna-
tives be considered. Many states have enacted similar legislation to apply to state or
state-licensed actions. Since 1990, a number of “programmatic” environmental impact
statements have been drafted.
Environmental impact of federal projects currently is performed in several stages:
environmental assessment, a finding of no significant impact (FONSI) if that is appro-
priate, an environmental impact statement (if no FONSI is issued), and a record of
the decision (ROD) made following the environmental assessment. In this chapter we
consider the methods for making an environmental assessment as well as introducing
the economic and ethical implications of environmental engineering.
Engineers ideally approach a problem in a sequence suggested to be rational
by the theories of public decisionmaking: (1) problem definition, (2) generation of
alternative solutions, (3) evaluation of alternatives, (4) implementation of a selected
solution, and (5) review and appropriate revision of the implemented solution. This
step-by step approach is essentially the NEPA process defined by the federal and state
governments. This chapter presents an overview of environmental impact analysis.
The specific analytical tools as well as the specific impacts and mitigation measures
are discussed in detail in the other chapters of the book. However, impact assessment
provides an integrated view of the problems of environmental engineering.
ENVIRONMENTAL IMPACTOn January 1,1970, President Richard Nixon signed NEPA into law, setting a national
policy to encourage “productive and enjoyable harmony” between people and their
environment. This law established the Council on Environmental Quality (CEQ),
which monitors the environmental effects of all federal activities, assists the President
in evaluating environmental problems, and determines solutions to these problems.
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