Matthews Band in sewage flap

The Dave Matthews Band says it is cooperating with Chicago authorities in their investigation of a waste-dumping incident and “will work quickly to make amends� if the group is found to be responsible.

About two-thirds of the 120 passengers on a Chicago River boat were doused Aug. 8 with roughly 800 pounds of raw sewage that police say was dumped by one of the band’s tour buses as it crossed a grated bridge.

A civil lawsuit filed by Illinois Atty. Gen. Lisa Madigan identified one of the band’s drivers, Stefan A. Wohl, as the person who dumped the sewage. The suit seeks $70,000 in fines.

In an unsigned letter posted on its website, the band said that the driver was the only person on the bus during the time that police say the incident occurred, and “he has told us that he had nothing to do with this incident.�