Updated

As families of two slain teenagers called for the closure of the abandoned Utah mine shaft where the teens' bodies were dumped, a state mining official said Friday she's hoping it can be sealed off.

The bodies now confirmed to be Riley Powell, 18, and Brelynne "Breezy" Otteson, 17, were dumped in the mine in late December. The teens were stabbed to death following a visit to a woman whose boyfriend had warned her not to have male visitors, Utah County sheriff's officials said.

They were found down a hole large enough to swallow a car, one of hundreds of abandoned mine shafts near the desert town Eureka, about 75 miles (120 kilometers) south of Salt Lake City, said Utah County Sheriff's Sgt. Spencer Cannon. It's nearly 1,800 feet deep, and if the bodies hadn't landed on a shallow ledge they might never have been recovered, he said.

Abandoned mines are a serious problem in the former silver mining area, "just sitting right there waiting for someone to fall in them or get put in them," Powell's father, Bill, told reporters at a Thursday news conference.

The West is dotted with abandoned mines, and there are about 20,000 in Utah alone, Hollie Brown said, spokeswoman for the Utah Division of Oil, Gas and Mining.

"Sadly, it's a great place to go and dispose of, unfortunately, bodies and other items," she said.

The state has closed several thousand abandoned mines, but the shaft known as the Tintic Standard No. 2 is on private land, she said. She's hoping the state can work with the landowner to seal it off.

Tim Buchanan with the Chief Consolidated Mining Company, the company that owns the land, declined to comment.

The bodies found Wednesday were believed to be the missing couple, but a Friday determination from state medical examiners made the identification official.

Under arrest on suspicion of aggravated murder and other charges is Jerrod W. Baum, 41. Police say he tied up the two teenagers, stabbed them to death and dumped their bodies in the abandoned mine shaft after they visited his girlfriend in late December. His attorney has not returned calls seeking comment.

His girlfriend told police that Baum told her he'd made Powell suffer after the teenage couple visited their shared home to smoke marijuana with her, but kept Otteson's death quick and painless because he felt bad, according to police documents.

He said he'd already warned his girlfriend about having male friends at the house and "it was too bad because he has never killed an innocent before," she told authorities, according to police documents.

The break in the case came Sunday, when police say the girlfriend was found with weapons in her car after an unrelated traffic stop. She led them to the mine where police eventually recovered the bodies.