A look at hidden dangers after at least 47,000 abandoned mines recorded in California
SAN FRANCISCO (KGO) -- California officials have identified at least 47,000 abandoned mine sites statewide, but many more may remain undocumented, creating ongoing risks for residents, visitors and emergency responders.
The challenge of locating and assessing those sites falls to California's Abandoned Mine Lands Unit, where a staff of six works to inventory mines, evaluate hazards and coordinate remediation efforts across the state.
"Six staff only, three engineering geologists and three environmental scientists. And we go out the entire state inventorying these mines, getting them on record, figuring out where the risks are, and then partnering with land-managing agencies on a potential remediation," said Kyle Johnson, program manager for the unit.
The dangers associated with abandoned mines extend beyond California. Recent incidents elsewhere in the country have included a Pennsylvania grandmother who died after falling into an abandoned mine while searching for her cat, a family car swallowed when a driveway collapsed into a mineshaft, and a roadway failure linked to an old mine.
In California, risks are associated not only with historic gold mines in the Sierra Nevada but also with former silver, copper, mercury and sandstone mining operations throughout the state.
To prepare for emergencies, rescue agencies conduct specialized training. During a recent exercise in Nevada County, firefighters and search-and-rescue volunteers used a tripod-style rope rescue system known as a vortex to simulate extracting a victim from a shaft.
"The way we're successful is training with our partners. So, today is a way for us to blend our talents in our operations. So, if we are called to a scene, those operations are seamless," said Jason Robitaille of the Nevada County Consolidated Fire District.
Responders said abandoned mines can contain unstable walls, hazardous gases and low-oxygen environments.
"We have to do air monitoring to make sure it's safe to go down to. We need respiratory protection to go down in there because if we don't take those things into consideration, we become part of the problem," Battalion Chief Josh Sunde said.
The dangers are not theoretical. In December, rescue crews in Nevada County responded after an off-duty firefighter searching for a stray dog fell into a hidden mineshaft concealed by thick underbrush. He dropped about 40 feet, injured his leg and was unable to climb out before rescuers brought him to safety.
Officials said many mine locations remain unknown.
"We don't. We've had incidents where some of the mines that, no one was aware of, or at least we were not aware of," Robitaille said when asked whether authorities know how many mines exist and where they are located.
For Melinda Chellew, the threat became personal tragedy. In April 2006, her son Jason Chellew was staying in a basement apartment beneath her home when he heard a rumbling sound. After stepping onto the carpet, he fell into an abandoned mine beneath the property.
"But they couldn't get him out because the earth just kept moving, and he was going deeper and deeper as the earth moved," Chellew said.
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His border collie, Junta, jumped in after him and also could not be recovered.
"Of course she did try to save him, but they couldn't get her out because her, she kept going lower and lower, as well," Chellew said.
The property was later found to be above an old gold mine. Over the following year, crews filled the 20-by-20-foot shaft beneath the house with more than 200 tons of concrete. Chellew still lives there.
"I felt really comfortable doing it. Now, my friends don't think that way. They think I'm a little crazy, but I'm not because in my heart, I know this is where I belong," she said.
Chollew said she decided to speak publicly because she wanted people to understand the true cause of her son's death.
"And it upset me only because I wanted the truth to be out there," she said. "I think it does because I only had one child, and I lost him in this tragedy. And I want people to know that this is a possibility. There are mines here."
Seven On Your Side Investigates recently toured the historic Tesla coal and sand mine near Tracy, including one opening where state officials installed a gate intended to prevent unauthorized entry while allowing bats to continue using the site. The gate was later damaged by a vandal.
"And we don't want you entering these mines, so please do not vandalize these, these gates. They're there for a reason," Johnson said.
According to state figures, 185 people have died in abandoned mines in California since 1950, while another 443 incidents have resulted in injuries or what the state classifies as near misses.
Officials said the work of identifying and evaluating abandoned mines continues, but the scale of the task remains significant.
