ATSDR works closely with communities to evaluate the public health effects related to redevelopment of brownfields properties. These are sites that were formerly used for industrial purposes and may still be contaminated with hazardous substances. ATSDR has worked at more than 400 brownfield or land reuse sites to assess health effects of potential exposure to hazardous substances. The agency has created resources to provide guidance to communities when planning redevelopment projects, including tools to evaluate the potential threat of chemicals at development sites. In addition to evaluating the health effects of contamination at specific brownfield sites, ATSDR encourages communities to monitor community health. One of the agency's brownfields projects was the Menomonee Valley in Milwaukee, Wisconsin, where the agency evaluated potential health effects of contamination at the site and worked closely with developers and the city.