CHAMPAIGN — A DeWitt County controversy is quickly gaining the attention of officials across East Central Illinois who say they want to protect the source of drinking water that is pumped into the homes of more than 750,000 people.

Twenty-two top-ranking officials from agencies around the region met in the Champaign City Building this week to discuss what might be done to stop Clinton Landfill from obtaining a federal EPA permit that would allow it to store polychlorinated biphenyl waste, which contains known carcinogens and is harmful to human health.

At stake, they say, is the Mahomet aquifer, a huge natural reservoir hundreds of feet below the landfill that provides drinking water to much of central Illinois.

The landfill, located about 2 miles south of Clinton, applied for the EPA permit in 2007. Since then, it has received attention in DeWitt County but has drawn little concern outside that area and has just recently come across the radar of officials elsewhere.

An EPA public-comment period has recently been extended to Aug. 14, and those officials who say they are trying to protect the region's drinking water are hustling to submit their comments.

"In a short period of time, we've generated quite a few letters of concern," Champaign City Manager Steve Carter said.

Opponents of the permit say it is possible that the PCB waste could leach into and contaminate the aquifer.

A representative from Area Disposal Service Inc., the Peoria-based parent company of Clinton Landfill, could not be reached on Wednesday. But the EPA has published information that says the proposal goes beyond federal requirements in protecting groundwater. Unique to the facility is "the number and extent of safeguards employed," according to EPA documents. "In many cases, the stringent design and performance standards contained in state and federal landfill regulations have been exceeded."

EPA geologists have concluded a layer of waterproof clay 150 feet underground would provide a natural protection against contamination. And Clinton Landfill would install three layers of liners, a liquid-waste collection system and a 3-foot layer of clay.

But George Roadcap, a hydrogeologist with the Illinois State Water Survey, said there is limited data to make any conclusions.

"The EPA geologists are relying on what information the landfill gives them, for the most part," Roadcap said. "They didn't have the resources to collect their own data."

There is little information on how water actually gets down to the Mahomet aquifer, Roadcap said.

"It may be well protected; it may not be as well protected as we hope," Roadcap said. He added that there are long-term concerns about what will happen to the waste after the landfill closes.

Mayors from Champaign and Urbana and the village administrator of Savoy attended this week's meeting. They were joined by the board chairman and top administrator from Champaign County, a representative from the University of Illinois, the mayor of Clinton, members of the Mahomet Valley Water Authority, the Illinois State Water Survey and Illinois American Water, among others.

All said they wanted in on the discussion of how to block the EPA permit.

"I think the one thing that pulls everyone together is our concern for the aquifer," Carter said.

The options may be few: The EPA has already given preliminary approval to the application and could formalize the agreement once the public-comment period is closed and all the materials have been reviewed.

While there is no reason that Clinton Landfill would be entitled to the permit, officials this week acknowledged that the EPA might be hesitant to withdraw its preliminary approval on public comment alone.

The group hopes to garner support from federal legislators — in the past, Sen. Dick Durbin and then-Sen. Barack Obama submitted comments to the EPA, as did U.S. Rep. Tim Johnson.