SACRAMENTO - Fourteen abandoned mines that pose a dangerous threat to San Bernardino County residents are being permanently sealed by the state of California.

The Office of Mine Reclamation, part of the Department of Conservation, and the California State Lands Commission will oversee the backfilling of 13 shafts and the installation of a heavy-steel barrier known as a cupola over a 14th shaft in October.

"Some of these sites probably date to the Gold Rush," said Doug Craig, head of the OMR. "Mining helped make California great, but the race to find gold and other minerals left a sometimes-hazardous legacy that we're working to mitigate."

A contractor last week, hired by OMR's Abandoned Mine Lands Unit backfilled six shafts near the Calico Ghost Town outside Barstow - just a mile from an abandoned mine that was the site of a fatal accident in 2006 - and three others that were part of the Trade Rat copper mine near Fort Irwin.

The Calico District boomed in the 1880s and went on to become the richest silver district in the state.

The area contains extensive abandoned mine workings, including numerous small shafts, collapses and underground voids waiting to collapse, according to a press release from the department of conservation.

Last year on private property in the same area, a man was killed after falling 50 feet down a hidden vertical opening located inside an adit, a horizontal tunnel with only one opening.
A week later, another man was paralyzed after falling into the same opening. Around 60 emergency workers helped in the rescue effort.

This week, OMR and the CSLC will start backfilling four additional abandoned mines including two near Lucerne Valley.

Also, the cement foundation for a bat-friendly cupola over a hazardous shaft in the Whipple Mountains near Needles has been laid.

"The backfills are low-cost, high impact projects that will permanently eliminate some hazardous openings in and near areas that are attractive to off-road vehicle riders," said Cy Oggins, manager of the Abandoned Mine Lands Unit. "Our work in Calico marked the 400th abandoned mine feature we've remediated since we started closing abandoned mines in 2002, so we're averaging one closure a week since we've begun."

A 2001 update to an earlier OMR report estimated that there are about 12,000 abandoned mines in San Bernardino County, far more than any other in the state.

Anyone who encounters an abandoned mine site is asked to not the location and call (877) OLD-MINE so the site can be investigated and ultimately remediated.