U.S. Sens. Dick Durbin and Tammy Duckworth and nine other members of Congress are demanding the federal government provide a time line for ridding three downtown Chicago buildings and a courthouse in Rockford of the bacteria that causes Legionnaires’ disease as well as harmful metals in drinking water.

The Sun-Times reported in August that three Loop buildings — Ralph H. Metcalfe Federal Building, John C. Kluczynski Federal Building and Everett M. Dirksen U.S. Courthouse — have Legionella, and in some cases, traces of lead or copper that exceed safe levels set by the government.

The Metcalfe Building is the Chicago regional headquarters for the U.S. Environmental Protection Agency, and also includes a children’s day care that detected Legionella and lead. Its employees — and workers at the Department of Housing and Urban Development — have filed grievances against their employers.

The Government Services Administration, which manages the buildings, said in August that it was working to resolve the contamination threat at the Loop offices. The agency has not responded to requests for updates over the last few weeks.