ARA Automated Finishing was convicted on Sept. 23 for releasing hazardous chemicals into a sewer line, which eventually flows into the San Francisco Bay, said the Santa Clara County District Attorney's Office in a press release. The company was caught after an investigation by the district attorney's office, the Sunnyvale Water Pollution Control Plant and the Sunnyvale Department of Public Safety. Part of the investigation involved the secret sampling of sewer contents coming from ARA operations.

ARA—which uses various chemicals in the process of finishing metal—was convicted two felonies and three misdemeanors, resulting in five years of probation and $100,000 in fines, penalties and other costs.

According to the press release, the company was caught releasing chromium, zinc, copper, nickel and other corrosives, which violated a number of regulatory limits.

The district attorney's environmental protection unit prosecuted the case.