Radioactive contamination is creeping into drinking water around the U.S.

When Jeni Knack moved to Simi Valley, California, in 2018, she had no idea that her family’s new home was within 5 miles of a former nuclear and rocket testing laboratory, perched atop a plateau and rife with contamination. Radioactive cesium-137, strontium-90, plutonium-239 and tritium, along with a mix of other toxic chemicals and heavy metals, are known to have been released at the industrial site through various spills, leaks, the use of open-air burn pits and a partial nuclear meltdown.

Once Knack learned about the Santa Susana Field Laboratory and the unusual number of childhood cancer cases in the surrounding community, she couldn’t ignore it. Her family now only drinks water from a 5-gallon (19-liter) jug delivered by Sparkletts water service. In August, she began sending her 6-year-old daughter to kindergarten with two bottles of the water and instructions to not refill them at school, which is connected to the same Golden State Water Company that serves her home.

Members of Parents Against Santa Susana Field Lab protested in 2018 out of concern over a proposal by the city of Simi Valley, California, to use more well water as drinking water. Image courtesy of Parents Against Santa Susana Field Lab

A federal report in 2007 acknowledged that two wells sourced by the water company were at risk of contamination from the site. “The EPA has said we’re at risk,” says Knack. And Golden State, she says, has at times used “possibly a very hefty portion of that well water.” To date, radioactivity above the natural level has not been detected in Golden State’s water.

Concerns across the country

All water contains some level of radiation; the amount and type can vary significantly. Production of nuclear weapons and energy from fissionable material is one potential source. Mining for uranium is another. Radioactive elements can be introduced into water via medical treatments, including radioactive iodine used to treat thyroid disorders. And it can be unearthed during oil and gas drilling, or any industrial activities that involve cracking into bedrock where radioactive elements naturally exist. What’s more, because of their natural presence, these elements can occasionally seep into aquifers even without being provoked.

The nonprofit Environmental Working Group (EWG, a partner in this reporting project) estimates that drinking water for more than 170 million Americans in all 50 states “contains radioactive elements at levels that may increase the risk of cancer.” In their analysis of public water system data collected between 2010 and 2015, EWG focused on six radioactive contaminants, including radium, radon and uranium. They found that California has more residents affected by radiation in their drinking water than anywhere else in the U.S. Yet the state is far from alone. About 80% of Texans are served by water utilities reporting detectable levels of radium. And concerns have echoed across the country — from abandoned uranium mines on Navajo Nation lands, to lingering nuclear waste from the Manhattan Project in Missouri, to contaminants leaching from phosphate mines in Florida.

To read more, go to ewg.org. Click the image to expand.

While ingesting radioactive elements through drinking contaminated water is not the only route of human exposure, it is a major risk pathway, says Daniel Hirsch, a retired University of California, Santa Cruz, professor who has studied the Santa Susana Field Laboratory contamination. “One thing you don’t want to do is to mix radioactivity with water. It’s an easy mechanism to get it inside people,” he says. “When you drink water, you think you excrete it. But the body is made to extract things from what you ingest.”

Strontium-90, for example, is among elements that mimic calcium. So the body is apt to concentrate the contaminant in bones, raising the risk of leukemia. Pregnant women and young kids are especially vulnerable because greater amounts of radiation are deposited in rapidly growing tissue and bones. “This is why pregnant women are never x-rayed,” says Catherine Thomasson, an independent environmental policy consultant based in Portland, Oregon. Cesium can deposit in the pancreas, heart and other tissues, she notes. There, it may continue to emit radioactivity over time, causing disease and damage.

Scientists believe that no amount of radiation is safe. At high levels, the radiation produced by radioactive elements can trigger birth defects, impair development and cause cancer in almost any part of the body. And early life exposure means a long period of time for damage to develop.

Health advocates express concern that the government is not doing enough to protect the public from these and other risks associated with exposure to radioactive contamination in drinking water. The legal limits set by the U.S. Environmental Protection Agency (EPA) for several types of radioactive elements in community water systems have not been updated since 1976. Further, many elements are regulated as a group rather than individually, such as radium-226 plus radium-228. And water system operators, if they are required to monitor for radioactive elements, only need to do so infrequently — say, every six or nine years for certain contaminants.

Meanwhile, private wells generally remain unregulated with regard to the elements, which is particularly concerning because some nuclear power plants are located in rural areas where people depend on private wells. More than one out of every 10 Americans use private wells or tiny water systems that serve fewer than 15 residences.

The Santa Susana Field Laboratory was rural when it was first put to use about 70 years ago. Today, more than 700,000 people live within 10 miles (16 kilometers). Recent wildfires have exacerbated these residents’ concerns. The 2018 Woolsey fire started on the property and burned 80% of its 2,850 acres (1,153 hectares). Over the following three months, the levels of chemical and radioactive contamination running off the site exceeded state safety standards 57 times.

The 2018 Woolsey fire, which started on Santa Susana Field Laboratory property, led to high levels of chemical and radioactive contamination running off the site. Photo courtesy of Peter Buschmann, USDA Forest Service.

Hirsch highlights several potential avenues for drinking water contamination related to nuclear weapons or energy development. Wind can send contamination off site and deposit it into the soil, for example. Gravity can carry contaminants downhill. And rains can carry contamination via streams and rivers to infiltrate groundwater aquifers. While vegetation absorbs radioactive and chemical contaminants from the soil in which it grows, those pollutants are readily released into the environment during a fire.

While no tests have detected concerning levels of radioactivity in Golden State’s water, advocates and scientists argue that testing for radioactive elements remains inconsistent and incomplete across the country. Federal and state regulations do not require monitoring for all potential radioactive contaminants associated with the known industrial activity on the site. For some of the regulated contaminants, water companies need only test once every several years.

“This is not an isolated matter,” says Hirsch. “We’re sloppy with radioactive materials.” 

“We need stricter regulations”

In 2018, around the same time that fires stirred up radioactive elements in and around the Santa Susana Field Laboratory, drinking water concerns arose just outside of Pittsburgh, Pennsylvania. Guy Kruppa, superintendent of the Belle Vernon Municipal Authority, had been noticing major die-offs of the bacteria in his sewage treatment plant. The bugs are critical for breaking down contaminants in the sewage before it is discharged into the Monongahela River. About 1 mile (1.6 kilometers) downstream is a drinking water plant.

Kruppa and his colleagues eventually linked the low bacteria numbers to leachate they accepted from the Westmoreland landfill. The landfill had begun taking waste from nearby fracking sites — material that included bacteria-killing salts and radioactive elements such as radium.

The Belle Vernon Municipal Authority subsequently got a court order to force the landfill to stop sending its leachate — the liquid stuff that flows off a landfill after it rains. “We sealed off the pipe,” Kruppa says.

Today, radiation is no longer discharging from his plant. Yet he remains concerned about where the leachate might now be going and, more broadly, about the weak regulation regarding radioactive waste that could end up in drinking water. The quarterly tests required of his sewage treatment plant, for example, do not include radium. “The old adage is, if you don’t test for it, you’re not going to find it,” adds Kruppa.

Concerns that radioactive elements from fracking could travel into community drinking water sources have been on the rise for at least a decade. A study led by Duke University researchers and published in 2013 found “potential environmental risks of radium bioaccumulation in localized areas of shale gas wastewater disposal.” Kruppa’s actions in 2018 drove widespread media attention to the issue.

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In late July 2021, the state of Pennsylvania announced it would begin ordering landfills that accept waste from oil or gas drilling sites to test their leachate for certain radioactive materials associated with fracking. The state’s move was a “good step in the right direction,” says Amy Mall, a senior advocate with the nonprofit Natural Resources Defense Council, which published a report on radioactive waste from oil and gas production in July. “We do need more data. But we don’t think monitoring alone is adequate. We need stricter regulations as well.”

The EPA drinking water standard for radium-226 plus radium-228, the two most widespread isotopes of radium, is 5 picocuries per liter (0.26 gallon). The California Office of Environmental Hazard Assessment’s public health goal, set in 2006 and the basis of EWG’s study, is far more stringent: 0.05 picocuries per liter for radium-226 and just 0.019 picocuries per liter for radium-228. “There is a legal limit for some of these contaminants, like radium and uranium,” says Sydney Evans, a science analyst with EWG. “But, of course, that’s not necessarily what’s considered safe based on the latest research.”

“We don’t regulate for the most vulnerable,” says Arjun Makhijani, president of the nonprofit Institute for Energy and Environmental Research. He points to the first trimester in a pregnancy as among the riskiest windows of development.

The known toxicities of radioactive contaminants, as well as technology available to test for them, have evolved significantly since standards were established in the 1970s. “We have a rule limited by the technology available 40 years ago or more. It’s just a little crazy to me,” says Evans. Hirsch points to a series of reports from the National Academies of Sciences, Engineering, and Medicine on health risks from ionizing radiation. “They just keep finding that the same unit of exposure produces more cancers than had been presumed,” he says. The most recent version, published in 2006, found the risk of cancer due to radiation exposure for some elements to be about 35% higher per unit dose than the 1990 version.

The EPA has begun its fourth review of national primary drinking water regulations, in accordance with the Safe Drinking Water Act. The results are anticipated in 2023. While advocates hope for stricter standards, such changes would add to the difficulties many drinking water providers already face in finding the finances and technology necessary to meet those regulations.

Seeking solutions

The aquifer beneath Winona, Minnesota — which supplies drinking water to residents — naturally contains radium, resulting in challenges for the city water department to minimize levels of the radioactive element.

Recent tests of Winona’s drinking water have found levels of radium above federal standards. In response to results, in April city officials cautioned residents that low-dose exposure over many years can raise the risk of cancer. However, they did not advise people to avoid drinking the water.

The city is now looking to ramp up their use of a product called TonkaZorb, which has proven effective in removing radium at other drinking water plants, notes Brent Bunke, who served as the city’s water superintendent during the time of the testing. The product’s active ingredient is manganese, which binds to radium. The resulting clumps are easy to sift out by the sand filter. Local coverage aptly likened it to kitty litter. Bunke notes that the city also plans to replace the filter media in their aging sand filters. Of course, all these efforts are not cheap for the city. “It’s the cost of doing business,” says Bunke.

Winona is far from alone in their battle against ubiquitous radium. And they are unlikely to be the hardest hit. “Communities that are being impacted don’t necessarily have the means to fix it,” says Evans. “And it’s going to be a long-term, ongoing issue.” Over time, municipalities often have to drill deeper into the ground to find adequate water supply — where there tends to be even larger concentrations of radium.

Some are looking upstream for more equitable solutions. Stanford University researchers, for example, have identified a way to predict when and where uranium is released into groundwater aquifers. Dissolved calcium and alkalinity can boost water’s ability to pick up uranium, they found. Because this tends to happen in the top 6 feet of soil, drinking water managers can make sure that water bypasses that area as it seeps into or is pumped out of the ground.

The focus of this research has been on California’s Central Valley — an agricultural area rich in uranium. “When you start thinking about rural water systems, or you think about water that’s going to be used in agriculture, then your economic constraints become really, really great,” says Scott Fendorf, a professor of earth systems science at Stanford and coauthor on the study. “You can’t afford to do things like reverse osmosis” — a spendy form of filtration technology.

In general, radiation can be very difficult to remove from water. Reverse osmosis can be effective for uranium. Activated carbon can cut concentrations of radon and strontium. Yet standard home or water treatment plant filters are not necessarily going to remove all radioactive contaminants. Scientists and advocates underscore the need for further prevention strategies in the form of greater monitoring and stronger regulations. The push continues across the country, as the issue plagues nearly everywhere — an unfortunate truth that Knack now knows.

Why doesn’t her family simply move? “I’m not saying we won’t. I’m not saying we shouldn’t,” she says. “But I don’t even know where we’d go. It really looks like contaminated sites are not few, but all over the country.”