There are speed limit signs, barrels and other barriers to slow vehicles down. But the box truck still managed to kill a toll taker and injure other drivers.
A union spokesperson told ABC7 that if investigators find anything to prevent future accidents like this one, the union will work to ensure those changes are made.
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A bouquet of flowers sits on the curb beside what's left of booth 14 at the Bay Bridge toll plaza. That's where 46-year-old Si Si Han was killed Saturday, only minutes after starting her shift.
"It's been rough," said Caltrans spokesperson Bob Haus. "Any time you lose a coworker on the job, it's terrible."
Haus says grief counselors are working with employees.
"It was just as one shift was ending and another was beginning," he said. "So quite a few actually saw. They are understandably traumatized. They will need a lot of help and support over the next several days."
He says Han's husband saw the crash as well.
The CHP is still investigating how this happened.
They arrested 32-year-old Daniel Berk on suspicion of DUI and vehicular manslaughter and say there's no indication the driver ever tried to slow down.
Han's coworkers wore orange ribbons Monday morning in her honor. Han's name will be added to a plaque with all 36 district 4 employees killed on the job.
Si Si Han's name will be added to this plaque. Names of all CalTrans employees killed while working. pic.twitter.com/mm0B9fPv5c— Elissa Harrington (@ElissaABC7) December 4, 2017
"I think we are in mourning right now," said toll worker Renaldo Iglesias.
Iglesias says Han was quiet, nice, and a very hard worker.
When asked if he felt safe at work, he said, "It's tough but we have to handle it day to day. But you know, I can't say if it's safe or not. But we leave it upstairs."
TRAFFIC: Current road conditions and backups
Toll workers take underground tunnels to staircases that lead to their booths.
In a statement, SEIU Local 1000 President Yvonne R. Walker said the union is working tirelessly to make sure members work in the safest possible conditions.
"Our SEIU Local 1000 family is mourning the loss of one of our own, Si Si Han, because of a tragic workplace accident. Not only did she serve our state with distinction for 10+ years, she was also a wife, mother, and friend to so many of us. Our deepest condolences go out to Si Sis family, coworkers and all those who knew her. Local 1000 works tirelessly to ensure that all our members work in the safest conditions possible. If investigators find there are actions that can be taken to prevent future accidents like this from happening, we will work to ensure those precautions are put in place."
Commuters can expect to see at least one booth closed on Tuesday morning.
Click here to help the families of fallen Caltrans workers.