Michigan officials say the state's investigation into old tannery waste disposal has expanded. The state Department of Environmental Quality says it's now investigating 75 sites for toxic industrial chemicals that were used by Wolverine World Wide to waterproof shoes.
Department spokesperson Mel Brown says about 26 locations have been referred to the shoe manufacturer for further testing. State officials say the latest testing area includes about 100 homes in Rockford.
The department says private well tests indicate that sludge may have been used as fertilizer in the area.
Brown has urged residents to drink bottled water until testing is completed.
Wolverine has distributed bottled water to residents as it conducts tests.
Gov. Rick Snyder has created a task force to oversee the response to contaminants found across the state.