In a trailer park tucked among the irrigated orchards outside Fresno 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 this community of farmworkers, puzzles over the notices posted on front doors: There’s a danger in their drinking water.
Tests for uranium, the notices warn, show a level considered unsafe by federal and state standards. The trailer park’s owners are legally required to post the warnings. But the notices are awkwardly worded and in English, a language few of the park’s dozens of Spanish-speaking families can read.
“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 to 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 up 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 Central California — 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.
At particular risk are the San Joaquin Valley families who rely on private wells; as many as one out of every four of them are unknowingly drinking dangerous amounts of uranium, researchers determined this year and last. Government authorities say long-term exposure to uranium can damage kidneys and raise cancer risks, and scientists say it can have other harmful effects.
In this swath of farmland, roughly 250 miles long and encompassing major cities, including Fresno, Bakersfield, and Modesto, the pre-treated water of up to one in 10 public systems has uranium levels that exceed federal and state safety standards, the U.S. Geological Survey has found.
More broadly, nearly 2 million people in California’s Central Valley and in the U.S. Midwest live within a half-mile of groundwater containing uranium over the safety standards, University of Nebraska researchers said in a study published in September.
Everything from state agencies to tiny rural schools are scrambling to deal with hundreds of tainted public wells — more regulated than private wells under safe-drinking-water laws.
That includes water wells at Westport Elementary School, where 450 children from rural families study outside the Central California farm hub of Modesto.
At Westport’s playground, schoolchildren take a break from tetherball to sip from fountains marked with Spanish and English placards: “SAFE TO DRINK.”
The school, which draws on its own wells for its drinking fountains, sinks and cafeteria, is one of about 10 water systems in the farm region that have installed uranium removal facilities in recent years. Prices range from $65,000 for the smallest system to millions of dollars.
Just off Westport’s playground, a school maintenance chief jangles the keys to the school’s treatment operation, locked in a shed the size of a garage. Inside, a system of tubes, dials and canisters resembling large scuba tanks removes up to a pound a year of uranium from the school’s wells.
The uranium gleaned from the school’s well water and other Central California water systems is handled like the nuclear material it is — taken away by workers in masks, gloves and other protective garments, said Ron Dollar, a vice president at Water Remediation Technology, a Colorado-based firm.
It is then processed into nuclear fuel for power plants, Dollar said.
Before treatment, Westport’s water tested up to four times state and federal limits. After treatment, it’s safe for the children, teachers and staff to drink.
Other Central California farm schools opt to buy bottled water in place of drinking fountains, which are off limits because of uranium and other contaminants.
We don’t have a choice,” said Terri Lancaster, principal of the 260 students at Waukena Elementary School in rural Tulare County. “You do what you have to do.”
Until winning a state grant to pay for trucked-in drinking water, her school was spending $10,000 a year from its general fund on bottled water.
Meanwhile, the city of Modesto, with a half-million residents, recently spent more than $500,000 to start blending water from one contaminated well to dilute the uranium to safe levels. The city has retired a half-dozen other wells with excess levels of uranium.
State officials don’t track spending on uranium-contaminated wells. But the state’s Water Resources Control Board identified at least $16.7 million the state has spent since 2010 helping public water systems deal with high levels of uranium.
In coming years, more public water systems likely will be compelled to invest in such costly fixes, said Miranda Fram, a researcher with the U.S. Geological Survey in Sacramento.
Fram and colleagues at USGS have taken the lead over the past decade in identifying the problem in farm centers, including Central California, which produces a quarter of the country’s agriculture.
Geologists and water experts are still piecing together the ways in which levels of uranium exceeding federal and state health standards are seeping into more public water systems and household wells in major farm areas.
Fram and her colleagues believe the amount of uranium increased in Central Valley drinking water supplies over the last 150 years with the spread of farming.
In California, as in the Rockies, mountain snowmelt washes uranium-laden sediment to the flatlands, where groundwater is used to irrigate crops.
Irrigation allows year-round farming, and the irrigated plants naturally create a weak acid that is leeching more and more uranium from sediment, said Fram and Bryant Jurgens, another USGS researcher.
Ongoing Drought is a Factor
Groundwater pumping pulls the contaminated water down into the earth, where it is tapped by wells that supply drinking water.
California is now experiencing its driest four-year span on record, and farmers and other users are pumping groundwater at the highest rates ever, helping to pull yet more uranium into areas of aquifers tapped by water wells.
“This has been a decades-long process that has occurred,” Jurgens said.
And even if authorities were to intervene to somehow curb uranium contamination — and no such effort is under way — “we expect that it’s going to take many decades to reverse this,” Jurgens said.
The USGS calculates that the average level of uranium in public-supply wells of the eastern San Joaquin Valley increased 17 percent from 1990 to the mid-2000s. The number of public-supply wells with unsafe levels of uranium, meantime, climbed from 7 percent to 10 percent over the same period there.
But the problem remains so unpublicized that even Fresno County farmer Mark Sorensen — who grows grapes and blueberries in one of the most impacted parts of the country, and deals with water issues routinely as a leader of the local farm bureau — admits to not knowing about it.
“To be honest, I have never spoken to anybody about uranium,” said Sorensen, a fifth-generation farmer. “I’ve never even heard of it in drinking water.”