A case was opened earlier this week, and investigators have been conducting interviews and surveillance to see if the allegations of criminal misconduct against CSRA Waste are true, Sheriff Ronnie Strength said.

"We felt there was probable cause to open a case, and we did," Sheriff Strength said.

He declined to comment on the specifics of the investigation, saying it could compromise their work. But if sufficient evidence is found, the case could be turned over to the district attorney's office, he said.

Mayor Bob Young met with Sheriff Strength earlier this week but declined to comment on the nature of his meeting. The mayor has been in Washington since Wednesday.

"We want to finish this up as soon as possible," Sheriff Strength said.

City Administrator George Kolb said he has been asked to provide the sheriff's office with information about the city's garbage service contracts and CSRA Waste. He declined to go into detail about what investigators might be looking for.

"We'll wait and see what this investigation reveals," Mr. Kolb said. "We're fully cooperating."

The probe, which investigators say they hope to have completed within a week, follows reports by The Augusta Chronicle that CSRA Waste was tossing recyclables away with regular household garbage.

CSRA Waste has been responsible for more than 70 percent of the city-run garbage pickup since Aug. 1 when trash collection was extended to an additional 23,000 customers.

Throwing away recyclables is not a crime, Sheriff Strength said, and that activity has nothing to do with the investigation. But newspaper reports resulted in increased attention on the company's activities, which led in part to a separate criminal investigation.

Reach Heidi Coryell Williams at (706) 823-3215.