A labor contractor was fined the maximum penalty for safety violations following a fatal car accident that killed one vineyard worker and left four others injured last summer in Santa Rosa, the U.S. Labor Department announced Monday.

The workers were carpooling to a vineyard owned by Jackson Family Wines on Aug. 3 when their Astro van drifted onto a gravel shoulder, jumped the ridge of a driveway, struck a pine tree and flipped, according to the accident report.

Mid-Valley Labor Services, a Madera-based contractor hired by Sonoma County's largest wine producer, was fined $21,100 for violating labor laws.

The Astro van was not properly insured, the company had not registered the vehicle with the Labor Department as is required when shuttling workers, it had non-functioning seat belts, and the 19-year-old driver was unlicensed, according to the Labor Department.

"This is an issue that the Department of Labor responds very quickly to," said Alberto Raymond, the agency's assistant district director. "They received the maximum penalties."

Ben Mascarenas, president of Mid-Valley Labor Services, said the van did not belong to his company and the employer played no part in arranging the transportation. The workers were carpooling to work that morning just like thousands of other people in the county, he said.

"They were just trying to get to work. Many don't have their own cars," he said. "There is no public transportation to the farms. There is no BART. There are no buses."

Mascarenas said he applauded the Labor Department for enforcing labor safety and preventing abuse of workers, but said he views the fines as a classic case of an over-reaching bureaucracy.

"We try to do our best," he said. "But the regulations have gone too far, and it's making it really hard to do business."

The Aug. 3 crash killed Manuel Acosta Montano, a passenger. The driver, 19-year-old Laureno Terrazas, fled and was later arrested and charged in connection with the crash, including a count of driving without a license.

Mascarenas said the company provided financial assistance to the worker's widow, including sending the body back to Mexico and paying for the funeral service.

"We didn't have to do that. But it was the right thing to do," he said.

Raymond declined to provide a copy of the Labor Department's investigation on Monday. While the investigation is closed, the government is still working to have Mid-Valley Labor Services pay $49,527 in back pay to 114 workers in Sonoma County.

Workers were not paid for attending daily 10-minute safety meetings that occurred before workers entered the vineyards in the morning, according to the Labor Department.