HAMMOND | Mayor Thomas McDermott Jr. says he's concerned that the BP Whiting Refinery wants to put more chemicals into Lake Michigan near the intake pipe for city drinking water.

Hammond's Water Works supplies water to residents of Hammond and 10 other communities, including Munster and Lansing. The intake pipe is about a mile from where BP is proposing to increase its wastewater discharge.

"Anybody who drinks water in Northwest Indiana should have the right to ask questions" about the increases, McDermott said. "I don't know what effect this will have on our drinking water."

BP spokesman Scott Dean said the company cleans all wastewater before it is discharged and that "99.9 percent" of what goes into the lake is pure water.

"We absolutely don't release sludge or toxic waste streams into Lake Michigan," Dean said. "We don't now, nor will we under this permit."

State and federal regulators have been working with BP to define how much more ammonia and "suspended solids" the company can release once it finishes construction of new equipment that will allow the refinery to process more Canadian crude petroleum.

Dean said the company has agreed to release far smaller quantities of the chemicals than it could have under the most permissive federal guidelines. He said more information is available at www.bp.com/us.

But McDermott said he opposes the increased discharges into the lake, and urged regulators to reconsider their support of increases that "could pose harm to Lake Michigan and those who depend on it for their drinking water and recreation."

McDermott said residents who oppose the increases can contact the Indiana Department of Environmental Management and the U.S. Environmental Protection Agency.