Brownfields have been defined as abandoned or underused industrial and commercial facilities where real or perceived contamination complicates expansion or redevelopment. This definition characterizes a tremendous number of properties as brownfields—because the severity of contamination is not specified and the environmental problems can be merely suspected as well as actually documented. Many brownfields are found in central cities and industrial suburbs with a legacy of traditional manufacturing. These sites include abandoned industrial and railroad facilities or [Page 297]manufacturing plants that are operating but show signs of pollution; they also include commercial lots such as dry cleaners or gasoline stations.