The National Transportation Safety Board has launched an investigation into the deaths of two BART workers who were struck by a train during maintenance work on Saturday.
NTSB investigator Jim Southworth said on Sunday that the agency will be in the Bay Area for the next four to 10 days collecting information
on what happened during the collision, which occurred shortly before 2 p.m. on a northbound track around one mile north of Walnut Creek.
The agency has walked the area of the collision and requested relevant documents, images and data from BART, and will interview those involved and inspect all involved equipment, Southworth said.
It could be six months to a year or longer before a final report is issued, however, Southworth said. That report could include recommendations for changes to prevent similar accidents in the future.
The four-car train involved in the collision was a "non-revenue" train, meaning that there were no passengers on board. Southworth said investigators would determine, among other things, who was driving the train, how fast it was going and why it was on the tracks at the time.
The train was not equipped with a forward-facing video camera that would show the tracks, but did have a video camera inside the cab that could
help show who was there when the collision occurred, he said.
The two men who were killed -- a BART employee and a contractor -- were inspecting a reported dip in the tracks on the Pittsburg-Bay Point line, when they were struck by an out-of-service train that was being moved to Concord, BART assistant general manager Paul Oversier said Saturday.
Oversier said the two men were highly experienced track workers.
Some question remains about who was at the controls of the train.
BART officials initially issued a statement on Saturday saying that an experienced operator was at the controls of the train but that it was
operating under computer control.
However, Oversier later partially retreated from that statement, saying he did not know who was at the controls of the train.