As part of U.S. EPA's Brownfields Action Agenda, Administrator Carol Browner removed approximately 30,000 sites from the Superfund Tracking System List (CERCLIS) as a result of further investigation of these properties. U.S. EPA released these sites because potential developers and others feared the CERCLIS designation. This map organizes these sites by Congressional district, showing how Superfund's far-reaching liability provisions affect every part of the country. These CERCLIS sites approximate a very small fraction of the brownfields problem (the U.S. General Accounting Office estimates that there are more than 400,000 brownfields through the nation).