Matt Mina, 17, was visiting his aunt and uncle and was spending the day in Newport Beach with his older cousin and other friends when he decided to dig a 6-foot pit and a trench that branched off to the side.
The sand on the sides of the trench collapsed on him suddenly while the others in his group were nearby playing bocce ball, he told The Associated Press.
As the sand pressed down on him, he wiggled his head to get a small pocket of air but then began to panic and lost consciousness after a few minutes. He realized no one could see what had happened because he had been hidden from view by the depth of the trench.
"It was really scary. I thought I'd just die," said Mina, who lives in Free Union, Va. "I didn't expect to be rescued. I didn't even know if anybody could hear me screaming for help or if anybody knew I was trapped."
A few minutes later, Mina's cousin, Eyan Alferos, went to tell him two pretty girls had arrived at the beach and wanted to hang out with them. He saw the sand was flat where the trench had been just moments before - and there was no sign of his cousin.
Alferos, 26, immediately began to dig but at first was shoveling sand from the wrong spot. Then the sand began to collapse on him, as well, and he had to be pulled out by another cousin when the sand reached his waist.
"There was a split second when I thought, `He's not going to make it because he's been down there way too long,"' Alferos recalled. "It's a miracle he's alive because his body shut down and he went unconscious. Who knows how long he was unconscious for?"
Lifeguards were at the scene almost immediately, followed by paramedics, and bystanders quickly began to help dig, using everything from snorkeling fins to toy shovels, Alferos said. Some surfers came in from the waves to help.
Video taken at the scene by a bystander shows dozens of people digging franticly then Mina being pulled out of the sand, half-conscious, in a black-and-white bathing suit. Alferos estimates his cousin was under the sand for 20 to 30 minutes.
"I just remember hearing people and people, like, pulling at me. I didn't expect it," Mina said. "I was surprised when I woke up."
The gritty feel of sand now gives Mina the chills and even on the ride to the hospital, the straps on the gurney holding him down made him feel panicked and claustrophobic. He was still covered in sand.
"It kind of freaked me out. I thought I was being buried again," he said of the straps. "I could feel the sand and the compression."
He's been picking sand out of his ears and hair since Wednesday, but otherwise Mina said he's doing well. He was released from the hospital after about three hours and talked to his mother that night.
Melissa Mina told the AP she got a call from her sister-in-law Wednesday evening while her son was in a hospital emergency room.
He grew up in Hawaii and has dug in the sand before, but she wasn't aware of how big the latest hole was until she saw it on TV.
"When I finally spoke to Matt last night I asked, `How does it feel to be buried alive?"' she said. "He said, `Different, mom. You have no idea how heavy the sand was."'
Associated Press Writer John Mone reported from Los Angeles.