A 53-year-old Tracy man has been sentenced to six months of home confinement for a cyber attack on the Discovery Bay Water Treatment Facility in 2021, prosecutors said. The sentence was handed down on May 8, according to the U.S. Attorney’s Office. A federal grand jury indicted Rambler Gallo last June, charging him with a single felony count of transmitting a program, information, code and command to cause damage to a protected computer, prosecutors said. Gallo pleaded guilty to the charge. Gallo was a full-time employee for a Massachusetts-based company that contracted with Discovery Bay to operate the town’s water treatment plant, which serves 15,000 residents.