The San Mateo County Coroner's Office listed the cause of death for 16-year-old Ye Meng Yuan as multiple blunt injuries consistent with being run over by vehicles.
Flight 214 collided with a rocky seawall just short of the runway at San Francisco International Airport on July 6, killing three girls and injuring dozens.
Police said the runway was covered with fire-retardant foam that rescuers had sprayed on the burning wreckage.
San Francisco Fire Chief Joanne Hayes-White said she does not see disciplinary action against the driver, calling it a "a tragic accident."
"There's not a lot of words to describe how sorry we feel, how badly we feel about it," Hayes-White said.