The Sustainability Imperative - Sustainable Design: The Science of Sustainability and Green Engineering - page 248

with elements defined by the National Academy of Engineering for inclusion in
their guiding strategies for the engineer of the future:

Engaging engineers and other professionals in team-based problem solving
Using technical tools
Interacting with clients and managers to achieve goals
Setting boundary conditions from economic, political, ethical, and social
constraints to define the range of engineering solutions and to establish
interactions with the public 36
Applying engineering processes to define and to solve problems using sci-
entific, technical, and professional knowledge bases

Case Study: The Warren County PCB Landfill Revisited
As noted above, the Warren County PCB landfill was constructed in 1982
to contain soil that was contaminated by the illegal spraying of oil containing
PCBs from over 340 km of highway shoulders. The landfill received soil
contaminated with over 100,000 liters of oil from 14 North Carolina counties.
The landfill was located on a 142-acre tract about 3 miles south of the town
of Warrenton, and held about 60,000 tons of contaminated soil collected solely
from the contaminated roadsides. The U.S. EPA permitted the landfill under
the Toxic Substances Control Act, which is the controlling federal regulation
for PCBs. The state owns approximately 19 acres of the tract and Warren
County owns the remaining acreage surrounding the state's property. The
containment area of the landfill cell occupied approximately 3.8 acres that
was enclosed by a fence. The landfill surface dimension was approximately
100 m 100 m, with a depth of approximately 8 m of contaminated soil at

the center. The landfill was equipped with both poly(vinyl chloride) and clay
caps and liners, with a dual leachate collection system. The landfill was never
operated as a commercial facility.
In 1994, a state-appointed Working Group, consisting of members of the
community and representatives from the state, began an in-depth assessment
of the landfill and a study of the feasibility of detoxification. Tests were con-
ducted using landfill soil and several treatment technologies. In 1998, the
working group selected base-catalyzed decomposition (BCD) as the most ap-
propriate technology (see Fig. B6.2). Approximately $ 1.6 million in state funds
had been spent by this time. In 1999, the Working Group fulfilled its mission
and was re-formed into a community advisory board. In the BCD process,
PCBs are separated from the soil using thermal desorption. Once separated,

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