Harmful, hard-to-eliminate toxins from firefighting foam and other industrial and household products have made their way into the water supply not just at Luke Air Force Base, as was announced last month, but across Arizona.

Along with the groundwater on base, at least 19 other water systems in the state have found the same chemicals in their drinking water in the last five years, a review by The Arizona Republic of federal data and state documents found.

Water systems, whether municipally operated or privately run, deliver water to Arizona households. The results show the toxins made their way into wells used for drinking water by 19 water systems.

Of those 19 systems, nine detected the chemicals at a level higher than the federal health advisory level for perfluorooctane sulfonate (PFOS) and perfluorooctanoic acid (PFOA), according to 2014 federally mandated tests, and subsequent tests by the state and public water systems.

Two of those nine systems are in the Phoenix area: Liberty Utilities in the West Valley and Tempe city water.

These water systems, along with most others in the state that detected high amounts of the chemicals, say they have since found ways to get the chemicals out of their water, either by shutting down the wells or treating the water, or both.

Tempe and Liberty officials say the chemicals in their drinking water wells are now well below the federal advisory level, and their water is safe to drink.

At Luke, the Air Force found the contaminants in the base's groundwater only, not in drinking water.

The other wells that tested high in the state have all been used for drinking water at some point.

But some of the wells were not being used for drinking water at the time of the tests, and water with high levels of the chemicals may have never made it to customers, because water systems often mix well water with other sources.

Officials with many of the affected water systems say there is no way for them to know how long the chemicals have been in the water, since they haven't historically tested for them.

Water systems don’t have to act

Their effort toget the chemicals out of their water was voluntary.

Even though the chemicals have been linked to cancer and other serious health issues, the Environmental Protection Agency hasn’t yet set an enforceable rule dictating at what level water systems need to remove PFOS and PFOA from their drinking water.

There’s debate across the country about what level is potentially hazardous to health, with some studies putting the level much lower than the EPA’s health advisory level of 70 parts per trillion, including one released this summer by the federal Agency for Toxic Substances and Disease Registry.

Some states, such as New Jersey, New York and Vermont, aren’t waiting for a federal standard. They are in the process of setting enforceable levels much lower than the EPA’s.

In Arizona, though, under state law, state agencies can’t make more stringent environmental rules than the federal government, unless the Legislature gives permission.

READ: Can Arizona fix its water problems? Here's what (and who) will answer that

Misael Cabrera, director of the Arizona Department of Environmental Quality, said he isn’t planning on suggesting the Legislature act on this until the health effects of the chemicals are more clear.

“Before I could make any suggestion like that, I would need to understand the toxicology a lot better, and the fact of the matter is there is still a lot of debate on the toxicology,” he said.

Cabrera said, from what his department has found, the chemicals aren’t as widespread in Arizona as they are in other states that are acting.

That said, the department has been actively testing for the two chemicals, and putting pressure on water systems to remove them from their water.

Pressure from the state

Water systems in the U.S. aren’t required to regularly test drinking water for PFOA and PFOS under federal law.

In 2014, though, water systems of a certain size nationwide were required to test for the chemicals, which gave states clues about the extent of their problems.

In Arizona, those tests discovered the chemicals higher than the advisory level in three systems:

Liberty Utilities.

Oatman Water Company.

Tempe’s city system.

After that, the state got a $121,000 federal grant to test further.

Through those tests, they identified four other contaminated systems:

Dry Gulch Water Company in Prescott.

Calportland Rillito Cement Plant near Tucson.

Tucson Water.

Orange Grove Ready Mix in Tucson.

The town of Marana and Metro Water District in the Tucson area also found high levels of the chemicals in their water, after conducting their own tests.

All but Dry Gulch and Marana have implemented fixes so the drinking water they serve has chemicals below the advisory level, Cabrera said, and those two are working on solutions.

At this point, the Arizona Department of Environmental Quality has tested water systems that provide drinking water to about 80 percent of the state’s population for PFOA and PFOS, including all areas believed to be high risk, Cabrera said.

The water systems that have turned off their wells or started new treatments say they have done so because they are committed to delivering clean and safe water to their customers. They have also faced some pressure from the state.

“We have successfully worked with every water system known to have a concern,” Cabrera said. “We let them know that if they aren’t willing to work with us, we always have the discretion to inform their customers.”

Where are the chemicals coming from?

The state hasn’t yet pinpointed exact sources for contaminants found in specific water systems, and it’s unlikely to investigate further until the EPA sets an enforceable level, Cabrera said.

It does have a list of potential sources, though.

PFOA and PFOS are in many different products, including industrial products and household products such as stain- and water-repellent fabrics, nonstick pans and paint.

While some states have found high amounts of the chemicals in the water near businesses that make those products, in Arizona, the main source is thought to be from a type of firefighting foam frequently used at Air Force bases, airports and other locations.

The Air Force is conducting tests around all of its bases and has found contaminated water on and around several bases in the U.S., including Luke.

The firefighting foam, used for decades at Luke and Davis-Monthan Air Force Base in Tucson, contains high concentrations of the chemicals, and easily seeps into the ground when not contained.

PFOS and PFOA spread easily and are hard to destroy or remove from water, giving them the nickname “forever chemicals.”

To find out where the chemicals spread in Arizona, the state put together a list of 45 potential sources of contamination, including Air Force bases, airports, industrial users and firefighting training facilities across the state.

The state tested 109 wells around these locations: 89 didn’t detect the chemicals, 14 detected the chemicals below the advisory level and six were above the advisory level.

Liberty starts treating water

During the required federal testing in 2014, Liberty Utilities found PFOS of 270 parts per trillion — or more than three times higher than today's federal advisory level — in one of its wells.

The well at the time had not been used for drinking water since 2011.

When the EPA lowered its advisory level to 70 parts per trillion in 2016, Liberty “took immediate and aggressive action to ensure the drinking water provided to customers remained compliant with health advisory levels for PFOA and PFOS on a continuous basis,” said Matthew Garlick, president of Liberty Utilities Arizona.

Liberty began treating the well to filter out the chemicals in 2016, and, once it was treated, began to use it again, “only on an as-needed basis during peak demand periods,” Garlick said.

Water safety is “of upmost importance” to Liberty, he said.

Liberty serves customers in several West Valley cities near Luke Air Force Base. The well that found high levels of the chemicals is in the area that Luke has identified as potentially contaminated from firefighting activities on the base.

The Air Force began testing around the base in April to see how far the chemicals spread. The results have not been released.

Tempe shuts down wells

Tempe found high levels of the chemicals in three of its wells during the mandatory 2014 federal testing. The tests at two of those wells showed the chemicals above the federal guidelines set two years later.

When the EPA set its advisory level in 2016, Tempe shut off all three wells, which feed into distribution points for drinking waterfor the entire city.

READ: Tempe water violates EPA drinking-water standards

By shutting down the wells, the city was able to get its water under the advisory level.

The city has the flexibility to leave the wells off because it gets its water from multiple sources, said Holly Rosenthal, who runs the city's water division.

Tempe could choose to mix in the water from the contaminated wells at a point to which the levels would still be under the advisory level, but Rosenthal said she has decided the wells will stay offline.

Tempe recently began to study how it can potentially treat the water and get the wells back online.

The city hasn’t tried to identify the source of the contaminants, Rosenthal said.

The state has identified a potential source: the Tempe APS Joint Fire Training Facility, which provides firefighter training for Tempe and APS firefighters.

Tucson systems take cautionary approach

The chemicals were detected in the groundwater in three main areas in Tucson during the 2014 federally mandated tests, state tests and tests completed voluntarily by water systems.

One large potential source of the chemicals there is Davis Monthan Air Force Base, which hasn't yet released the results of its site investigation, as Luke did in April.

Three water companies provide drinking water to the public from the three affected areas: Tucson Water, the town of Marana and Metro Water.

Metro Water's wells were already not being used for drinking water at the time the chemicals were detected over the advisory level.

Tucson Water has since found ways to get its water below the advisory level, either by shutting down wells or through treatment.

Tucson Water also is expanding its treatment plant at one of the sites to more effectively reduce the chemicals in the water, said Tim Thomure, Tucson Water director.

Tucson Water is unique among water systems in the state in that it set an internal goal of reducing the chemicals far below the advisory level, to below 18 parts per trillion, across its system.

It wants to be ultraconservative, Thomure said.

In Marana, there's no easy fix.

The town found the chemicals in two of its seven separate water systems through its own voluntary testing, said Scott Schladweiler, deputy water director for the town.

The tests in 2016 showed levels above the federal guidelines, between 80 and 109 parts per trillion, in all six wells in the two systems.

Because all wells in the two systems were affected, they couldn’t just shut them down.

The town just borrowed $15 million for new treatment plants that will filter the chemicals out of the water. It has recommended that residents use filters at home, as well.

Town officials haven’t pinpointed a specific source for the chemicals, but Schladweiler said they have their theories.

They are downstream the Santa Cruz River from Tucson, since that river flows north from Tucson, so anything dumped in Tucson could end up finding its way to the groundwater there, he said.

Last year, Marana and Tucson Water filed a joint lawsuit in Pima County Superior Court against 3M and four other manufacturers of the toxic firefighting foam to try to recover the costs of treatment.

Other systems come up with solutions

The two other water systems in or near Tucson that have detected high levels of the chemicals in their drinking water are private businesses, Calportland Rillito Cement Plant and Orange Grove Ready Mix in Tucson.

They do not distribute the water to the public, and they provide bottled water to employees, according to information from the Arizona Department of Environmental Quality.

Oatman Water Company, another water system that detected high levels of the chemicals, is a small, privately owned drinking-water company that serves about 500 people in Oatman, a community in western Arizona.

One of its wells tested the chemicals at 330 parts per trillion during the 2014 federal tests. The company took that well offline.

The last known affected water system in the state, Dry Gulch, actually serves just one restaurant in Prescott, according to Cabrera. The department is helping the water system identify potential point-of-use treatment.

Reach the reporter at jen.fifield@azcentral.com or at 602-444-8763. Follow her on Twitter @JenAFifield.

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