State environmental officials are investigating the recent release of industrial sludge into two Opelika waterways.
Alabama Department of Environmental Management spokesman Scott Hughes says the agency received a call Friday from the city of Opelika regarding some material that had been found in the Pepperell Branch and Saugahatchee Creek.
Hughes tells the Opelika-Auburn News (http://bit.ly/V9RInR) that the release likely started sometime Thursday afternoon.
Officials say the Birmingham area's air-pollution rating is the best it has been in more than three decades.
The Alabama Department of Environmental Management says the region including Jefferson, Shelby and Walker counties has met a set of federal pollution standards for the first time in more than 30 years.
The state asked federal officials to certify that the area was in compliance, and the Environmental Protection Agency agreed.
Environmental officials say the improvements in air quality result from reductions in emissions mandated by government regulators.