ABSTRACT
We walk on a history book every day, yet most of us are not fully aware of its signiœcance. The arrangement, thickness, and composition of the sediment layers beneath our feet have a profound in¡uence on where cities are located, how buildings are constructed, where roads are built, and perhaps most important to the development and redevelopment of our urban centers-how contaminants behave and how they affect the environment and people.
