A temporary wall has been placed to protect the rail line from falling debris.
"This pile barrier wall is more like a grate that's going to collect any debris that falls from the landslide," explained Orange County District 5 Supervisor Katrina Foley.
Experts like Brett Sanders, who's a professor of civil and environmental engineering, urban planning and public policy at UC Irvine, are studying the shifting landscape and said the slope is made up of materials that loosen up when moisture sets in.
"It's more of like a mixture of soil," Sanders said. "A mixture of sand, and gravel and silts that when wetted, starts to flow like a liquid."
He said people across Southern California live on hillsides just like the one in San Clemente. Sanders said residents need to be aware that this could happen to them.
"Most property owners have access to geotechnical reports. They can research the soil conditions on the property they own and learn more about the safety of their property and they can look for insurance," Sanders said.
As far as finding a permanent solution in San Clemente, he said it is possible.
"That is done by designing sort of often deep piles or structures that sort of, like pins, that can stick deep into the ground and then you build up with that type of a foundation," said Sanders.
However, he said that will require money.
Foley, who also serves on the Board of Directors for the Orange County Transportation Authority, which owns the rail line, said millions of dollars have already been committed to addressing the issue, but more is needed.
"It's a collaborative effort," she said. "It takes all different agencies from the federal government all the way down to the local to make this happen."
Sanders said beach erosion could also cause slope instability because hillsides have less protection when sand is washed away.
Passenger train service through San Clemente is set to restart again on Monday, July 17.