NR 2001-02
January 24, 2001

Contact: Carol Dahmen
Mark Oldfield
Don Drysdale
Ed Wilson
(916) 323-1886


WEIMAR, Ca. -- David Stam didn't mean to eavesdrop, but he couldn't help but overhear his three children talking about the "hole in the ground" they had discovered last spring near the family's property in Weimar, about 38 miles northeast of Sacramento near Colfax. He was absolutely right to be alarmed.

"We had the property cleared and the kids were running around playing," Stam recalled. "I asked them, "What's this hole you're talking about?' Once I saw it, I told them, 'If you ever want to see the outside of the house again, stay away from that hole.' "

The "hole" discovered by Stam's twin 10-year-olds, Danielle and Gabrielle, and 13-year-old son Kyler, is 5 1/2 feet in diameter and at least 32 feet deep. It is probably a test shaft, one of the many thousands of potentially hazardous legacies of mining in California.

"We were lucky," said Kim Hughes, Stam's wife. "We moved here five years ago when the kids were very small. They or one of their friends or one of the dogs could have fallen in."

A recent report following a nearly three-year study by the California Department of Conservation concludes that there are at least 39,000 abandoned mine sites in the state. Prior to this report, the number of abandoned mines reported in California was based solely on old databases and ranged from a low of 7,000 to a high of 20,000.

Of the 39,000 abandoned mines, approximately 32,760 (84 percent) present physical safety hazards, many with several openings such as the one on Stam's property that pose a threat to humans and wildlife. Other physical hazards include unstable highwalls or structures such as mine buildings that could collapse at a touch; dark, twisting tunnels in which an explorer could become hopelessly lost; and disease-carrying, predatory or poisonous animals which sometimes make old mines their homes.

On November 30, a deer was discovered 15 feet down an abandoned mine shaft in Mokelumne Hill. The landowner had no idea the shaft existed on the property. The buck, nicknamed "Lucky" by local children, was pulled to safety after several hours and released. Fortunately for Stam, the Department of Conservation contracted with Foam Concepts Inc. of Aurora, Minn., to permanently close the hole on his property as a demonstration of what can be done with some hazardous openings. The foam sealant requires no equipment, no power source, can be backpacked into remote areas and is environmentally friendly.

"I wanted that hole sealed up for my kids' safety," Stam said. "It's a big hazard. Kids will be kids."

The DOC study states that approximately 4,300 (11 percent) of California's abandoned mine sites present environmental hazards. There are acute environmental hazards such as old explosives, drums of chemicals or direct exposure to toxic mine tailings. There are also subtle hazards inside of a mine --

poisonous gases or low oxygen levels. More often, there are chronic environmental hazards. Contaminated runoff from abandoned mines affects land, groundwater, streams, rivers and lakes in many areas throughout the state. Water can carry heavy metals associated with acid-rock drainage, mercury from placer gold processing, mercury from mercury mines, arsenic, asbestos and chromium. Windblown dust containing contaminants such as chromium and asbestos also is a concern.

"The mining industry today is high tech and generally environmentally conscious," DOC Director Darryl Young said. "But the historic mining industry that helped build this state developed in a time of less-sophisticated mining methods and before environmental regulations. Since most of these sites date back to the 19th century, the individuals or companies responsible for the problems are no longer present to assist with remediation and reclamation.

"Additionally, there isn't a statewide clearinghouse for information or a coordinated statewide effort to address abandoned mine lands. But the danger of abandoned mines is becoming more evident as the population grows in high-density abandoned mine areas such as the Sierra Nevada foothills."

Another example of the danger is ongoing near Grass Valley, where a Bay Area family's dream home, built over a mine shaft that had been covered with topsoil, had to be condemned after the ground collapsed under it.

Approximately 50 percent of the abandoned mines are on private lands, while 48 percent are on federal lands and 1.5 percent on state lands. The report recommends field visits to assess the physical hazards of each site. It states: "A mine site may be represented by one five foot shaft, presenting only a safety hazard; or a site may include 42 shafts, three waste piles, two tailings dams and a processing area, all encompassing in excess of 200 acres and presenting both safety and environmental hazards."

With a limited staff, DOC's Office of Mine Reclamation/Abandoned Mine Lands Unit worked from September 1997 to June of 2000 to produce the statewide inventory and report. Staff collected and entered data for 790 mine sites and 3,980 features in 21/2 years. Thus, while confident in its extrapolated figures, the report points out that only 1.5 percent of the state's sites and features have been located and recorded using modern methods.

The report -- entitled "California's Abandoned Mines: A Report on the Magnitude and Scope of the Issue in the State" -- was mandated by and has been given to the Legislature. It concludes, "in general, the existing authorities and funding mechanisms are inadequate to address this huge statewide issue." The abandoned mines report can be accessed here

DOC's Office of Mine Reclamation urges citizens who come across a suspected abandoned mine to call its toll-free number, 1-877-OLD-MINE (653-6463). That's how DOC learned of Stam's problem.