http://www.epa.gov/brownfields/
U.S. Environmental Protection Agency
Brownfields are real property, the expansion, redevelopment, or reuse of which may be complicated by the presence or potential presence of a hazardous substance, pollutant, or contaminant. On this site, you can find information about US EPA's Brownfields Program including the Brownfields Law, US EPA Brownfields Grants, technical tools and resources as well as information on brownfields projects across the county.