Clear Creek off-roader paradise lost due to asbestos

But on Thursday, a 48-square-mile swath of the Diablo Mountains in San Benito and Fresno counties was labeled a virtual death zone where five visits a year over three decades could lead to lung cancer and other crippling diseases.

The recreation area was abruptly closed for the foreseeable future by the federal Bureau of Land Management, after a three-year by the Environmental Protection Agency found that dangerous levels of asbestos dust were being stirred up by motorcycles and other off-road vehicles.

Any human use -- even camping and hiking -- was deemed potentially dangerous, especially to children, and outlawed until the BLM develops a new plan for the area.

Clear Creek, which registers 35,000 visits a year, has long been known as the largest U.S. deposit of asbestos, a natural mineral and known human carcinogen. It harbors an EPA-designated toxic Superfund site, the former Atlas asbestos mine. Previous studies over several decades found high levels of asbestos in the area, but the results were not as conclusive as in the new 160-page assessment, EPA officials said Thursday.

For the last three years, the BLM has closed the area from June to October, the dustiest months. Closing the site year-round was "an extremely tough decision," said bureau Field Manager Rick Cooper. "But my first priority must be protecting the health of visitors and employees."

The bureau, which first studied Clear Creek asbestos in 1992, has warned visitors in parts of the area to avoid breathing dust and drinking water from the creek. BLM employees are required to wear respirators on dusty days and to decontaminate after each visit.

But off-roaders have largely ignored the warnings. Don Amador, the western representative of the BlueRibbon Coalition, a national off-road group, said his group was raising funds to challenge the closure in court.

The type of short-fiber asbestos in the region, known as Coalinga chrysotile, he contended, is "not a health risk." Noting that the management area, which has 800 miles of trails, has been named one of the top 10 off-road areas in the nation by motorcycle magazines, he added, "We are in for a long, hard battle."