SUNOL, Calif. (KGO) -- ACE Train officials are now looking into the possibility of using sensors to detect when debris falls on the tracks after a mudslide caused a train to derail Monday night.
The trains are running again on Wednesday, a day after the accident.
ACE Train passengers couldn't help but get out of their seats and look out the window Wednesday morning at the site of the train derailment as they passed by it for the first time.
Some felt a little anxious for their own safety - all said they had the victims on their minds.
"Little nervous, little scary. I am trying to imagine how those people felt," passenger Lisa Lizarrago said.
"It's pretty overwhelming. It must have been scary. It's quite a drop, we didn't think it was that far down when we saw it on the news," passenger Brian Grewal said.
The drop was down an embankment and into the Alameda Creek, where one of the two derailed train cars landed.
Nine people were hurt in Monday night's crash - all survived.
Work crews cleared the wreckage from the tracks by late Tuesday and train service was restored Wednesday.
"I was happy to have it back. It is my only mode of transportation into Silicon Valley," Lizzarago said.
Ridership was down by about 200 people on each of the morning's first few trains. ACE officials don't know if that's because people were nervous about taking the train or just didn't know that trains were running again.
Those who did decide to ride say this still beats driving. "I don't want to drive. I drove yesterday. Traffic was really, really bad," another passenger said.