The concepts of industrial ecology are now a major
part of industrial engineering. Their rise to prominence
is partially due to the environmental laws passed in the last 20 years, which include Clean Air Act,
Clean Water Act, Resource Conservation and Recovery
Act, (all in 1970s); Pollution Prevention Act of
1990, Clean Air Act Amendments of 1990, and Intermodal
Surface Transportation and Ef®ciency Act of
1991. (Brown, 1989) Industry's emphasis on the
environment is in addition a response to public awareness
of environmental issues and a response to the
market force of competition, technological advances
in recycling, and the ef®ciency of machines (Piasecki,
1992).