FRESNO, Calif. (AP) -- In a trailer park tucked among irrigated orchards that help make California's San Joaquin Valley the richest farm region in the world, 16-year-old Giselle Alvarez, one of the few English-speakers in the community of farmworkers, puzzles over the notices posted on front doors: There's a danger in their drinking water.

Uranium, the notices warn, tests at a level considered unsafe by federal and state standards. The law requires the park's owners to post the warnings. But they are awkwardly worded and in English, a language few of the park's dozens of Spanish-speaking families can read.

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"It says you can drink the water -- but if you drink the water over a period of time, you can get cancer," said Alvarez, whose working-class family has no choice but keep drinking and cooking with the tainted tap water daily, as they have since Alvarez was just learning to walk. "They really don't explain."

Uranium, the stuff of nuclear fuel for power plants and atom bombs, increasingly is showing in drinking water systems in major farming regions of the U.S. West -- a naturally occurring but unexpected byproduct of irrigation, of drought, and of the overpumping of natural underground water reserves.

An Associated Press investigation in California's central farm valleys -- along with the U.S. Central Plains, among the areas most affected -- found authorities are doing little to inform the public at large of the growing risk.

USGS researchers recently sampled 170 domestic water wells in the San Joaquin Valley, and found 20 to 25 percent bore uranium at levels that broke federal and state limits.

State and federal regulators say the U.S. Congress, outlining drinking water standards, has limited their enforcement authority to public water systems. "Your home's your castle. If you've got a well at home, that's your business," said Bruce Macler, a San Francisco-based water program toxicologist for the U.S. Environmental Protection Agency.

Uranium is on the radar of California water officials, but the officials are paying more attention to other farming-related contaminants, including nitrates, as well as simply having enough water in the fourth year of the state's drought, said John Borkovich, head of water quality at the state Water Resources Control Board.

"When it comes to private domestic wells, we do what we can to get the word out," Borkovich said. "It's safe to say that there's always more that can be done."

The Associated Press commissioned sampling of wells at five homes in the countryside outside Modesto, to look more closely at whether unregulated private wells that families depend on were as vulnerable as contaminated public water systems nearby.



The results: Water from two of the five wells contained dangerous levels of uranium.

None of the five families, however, had ever heard that uranium could be a problem in groundwater -- let alone that it was a problem in their area.

"That's something I'm sure a lot of people are unaware of," said Reyna Rico, whose rural home overlooking farm fields had a well that tested three times the federal and state health limits.

"It would be nice to be informed, so we can make an informed decision, and those wells can be tested," said a resident nearby, Michelle Norleen, who was relieved to know that her own water -- unlike those of two of her neighbors -- tested below the limits in the AP sampling.

Even for bigger water systems for which government help is available, accessing safe water doesn't always come quickly. That's true at the Double L Mobile Ranch outside Fresno, where Giselle Alvarez lives in the one-room trailer with her mother and father.

Authorities have recorded years of tests showing dangerous levels of uranium in the water provided to the Double L's low-income residents.

The park's owner, Carl Hunt, minimized the health risks to the families who live there.

"Not afraid of that water at all," Hunt told the AP.

An independent water test commissioned by the AP found water at Hunt's trailer park remained over the limits for uranium.

Officials trying to set up delivery of safe water for the Double L's families have arranged with a local farm town, Kerman, to run its own water lines out to the trailer park -- but Kerman is awaiting funding to deal with its own, uranium-contaminated well first. State officials expect it will take another three years to get safe water to the trailer park.

For now, families in the rural trailer park mostly throw away the regular water notices, unable to comprehend their meaning. Suspicious in general of the park's tap water, families at the Double L who can afford it buy bottled water.

That doesn't include Alvarez's family.

"We can't really do anything about it," she says on the wooden steps of her mobile home. "As you can see, we're not rich."

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