SAN FRANCISCO (CBS SF) — The California Public Utilities Commission has fined BART a record $1.348 million for an accident that killed two transit agency workers as they were inspecting a track during the 2013 strike.

The agency imposed the fine at its Thursday meeting after an investigation revealed that a BART trainer was on his cell phone and wasn’t properly supervising his trainee at the time of the accident on the East Bay tracks.

It also found that the train never blew its horn as a warning and that the agency failed to provide a timely and adequate investigative report. The decision included a 3-year probation period allowing the agency to improve its safety policies and reduce the fine by 50 percent.

BART engineer Christopher Sheppard and consultant Laurence Daniels were checking on a dip in the rail north of the Walnut Creek station when they were struck by a train at around 1:44 p.m.

Both were fatally injured in the accident. A trainee was at the controls of the train at the time of the accident with a supervisor riding along.

The deaths occurred in the second full day of a strike by two of BART’s unions, the Service Employees International Union Local 1021 and the Amalgamated Transit Union Local 1555.

“These fatalities were totally preventable,” CPUC Commissioner Liane Randolph said in a statement. “We cannot undo the harm to Mr. Sheppard and Mr. Daniels or their families, What we can do is to make sure that BART makes safety its number one priority now and in the future.”

The transit agency must also comply with various orders, including tracking and submitting a report on all violations of safety rules, re-evaluating its current safety training programs, and posting a sign at each station about the CPUC fine.

BART issued a statement in response to the CPUC’s decision, saying it is “currently evaluating” it and that the agency “has worked with the CPUC and others to identify and address all potential causes of the accident.”

“BART responded swiftly to the accident by abolishing its prior wayside access procedures, working with an independent association to create and implement new wayside access procedures, and retraining all employees and contractors who might access BART’s wayside,” the statement said.

BART officials said they have put up trackside physical barriers to protect crews and installed $2 million worth of safety barrier fencing.

“Nothing is more important to BART than safety,” the statement said. “A safer system for our employees will provide for a safer system for our riders and a better BART.”

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