PACIFICA (KPIX) — Somewhere below the jagged cliffs of the San Mateo coast, beneath the churning surf, Dan Moss hopes he will find the body of his son, Richard.

Twenty-one-year-old Richard Moss went missing in late May and investigators now believe his car went off the road on Highway 1 south of Pacifica.

The sea has tossed up tantalizing evidence of Richard’s whereabouts — his AAA card and a tire from his car have washed ashore — but, so far, efforts to locate the car or his remains have been unsuccessful.

The search has taken a toll on the Moss family.

“I wouldn’t wish this on anyone to be honest with you,” Dan Moss said.

In the meantime, Dan Moss has been working with other families who have lost loved ones along this stretch of Highway 1 to convince Caltrans to install a guard rail. Families like the DeAlbas. In September, 2016, Rose DeAlba died when her car plunged into the sea at the same spot where Richard Moss is believed to have perished.

“Our main goal here is for another person not to lose their life. If there were barriers in place, both my sister and Richard may have had a chance to live,” Rose’s sister Lorina DeAlba said.

“(Richard) shouldn’t have died. Rose shouldn’t have died because they should have put up these barriers a long time ago,” Dan Moss said.