The Air Force ignored decades of warnings from its own researchers in continuing to use a chemical-laden firefighting foam that is a leading cause of contaminated drinking water for at least 6 million Americans, including thousands of people south of Colorado Springs. Multiple studies dating back to the 1970s found health risks from the foam, and even an agreement 16 years ago between the Environmental Protection Agency and the foam's main manufacturer to stop making the substance did not curtail the Air Force's usage. Until drinking water tests announced by health officials this year revealed contaminated wells here, the Air Force did almost nothing to publicly acknowledge the danger of the firefighting chemical.

That contamination sent residents across southern El Paso County scrambling to buy bottled water and to test their blood for the toxic chemical, which, when ingested, can remain in the body for decades.

The Gazette's investigation into the military's research of perfluorinated compounds, the intensely powerful chemical in the foam, found:

Studies by the Air Force as far back as 1979 demonstrated the chemical was harmful to laboratory animals, causing liver damage, cellular damage and low birth weight of offspring.

The Army Corps of Engineers, considered the military's leading environmental agency, told Fort Carson to stop using the foam in 1991 and in 1997 told soldiers to treat it as a hazardous material, calling it "harmful to the environment."

The EPA called for a phaseout of the chemical 16 years ago and 10 years ago found the chemical in the foam "likely to be carcinogenic to humans."

Despite the warnings, the Air Force still uses the chemical in Colorado Springs, with at least 600 gallons of the firefighting chemical at Peterson Air Force Base. While that might not sound like much, it is mixed as a 3 percent solution with water. At that ratio, 600 gallons of chemical would combine with about 20,000 gallons of water to make 80 tons of fire suppressant.

The service plans to phase out the chemical in its firetrucks in coming weeks, but the Air Force still hasn't determined when it will remove the chemical from firefighting foam systems at Peterson's hangars.

The urgency of the issue came clearly into focus last week when Peterson Air Force Base announced the release of an additional 150,000 gallons of water polluted with the chemical into the Colorado Springs sewage system and from there into Fountain Creek.

After acknowledging the spill, Peterson officials said they weren't required by law to notify downstream users of the water in the contaminant's path.

Colorado Republican U.S. Sen. Cory Gardner said he's upset that the Air Force apparently knew the hazards of its firefighting foam but kept spraying it in Colorado Springs above the shallow Widefield aquifer.

"It is alarming that a substance was used that people knew then was a dangerous substance," Gardner told The Gazette.

The Air Force says some of its early studies were flawed but hasn't explained its apparent lack of reaction to the piles of later studies finding the foam toxic.

Air Force Undersecretary Miranda Ballentine highlighted the Air Force's $24 million effort to deliver clean water to the Pikes Peak region and elsewhere and defended the toxic foam as the "only fire-fighting product that met military specifications used to protect people and property from aviation fuel-based fires.

"The Air Force takes ownership of the possible negative impacts of our fire-fighting mission, and where we are responsible we will do the right thing to protect people and the environment," she wrote in an email to The Gazette.

But even as the Air Force spends millions of dollars to filter water from the fouled aquifer below Security, Widefield and Fountain, the problem could last for generations.

"The problem is that people now have a sense of false security - they think if it's out of the water, then you're out of danger," said Dr. Paul Brooks, a West Virginia physician who led a study of the effects of such chemicals on 69,000 people. "The problem is that people who were contaminated built it up."

The firefighting chemical sticks in the human body like few others. Its half-life, the time it takes the body to part with half of the chemical in the blood, is 5.4 years - 60 times that of lead.

EPA-mandated testing found at least 6 million Americans are dealing with water contaminated by the firefighting chemical and similar compounds - with many of them drinking from wells that likely were fouled by the Air Force, other military services or manufacturing sites.

Studies show that such chemicals can slowly kill. They can cause immune system and liver damage and have been linked to cancers, especially of the kidneys and testicles. Fetal development problems and low birth weight are a concern. And at a minimum, the firefighting foam can cause high cholesterol, a precursor to heart disease.

Exactly how the foam's chemical harms people remains unclear, though scientists have strong theories. Researchers generally agree the chemical doesn't directly damage human genetic material. Rather, it has largely been shown to suppress the immune system - allowing disease and ailments to surface over time.

Each person's risk is based on myriad factors, including one's genetic makeup, lifestyle, gender and the length of exposure to the chemical.

"It just tells us that it's not possible under our current testing guidelines to fully capture every potential toxicological effect that could occur from exposure to a synthetic compound," said Jamie DeWitt, associate professor of pharmacology and toxicology at the University of East Carolina's Brody School of Medicine.

"I think it's important that the people who are getting exposed understand that these exposure levels are based on probabilities," DeWitt said. "So exposure does not equal toxicity - it equals probability of toxicity at a sustained exposure."

'We bathed in it'

While the Air Force has offered $4.3 million to help filter water in the Security, Widefield and Fountain areas, it claims that serious concerns first arose in 2009 - 30 years after its first known studies into the toxic effects of the chemical and 16 years after the EPA and the chemical's largest manufacturer, 3M, issued a strong warning. By that time, such man-made chemicals had been found on every continent.

"3M data supplied to EPA indicated that these chemicals are very persistent in the environment, have a strong tendency to accumulate in human and animal tissues and could potentially pose a risk to human health and the environment over the long term," the EPA said in a 2000 news release.

The EPA has yet to ban the chemical. The Air Force says it will remain in use through the end of the year. The military and the Department of Veterans Affairs said they have no plans to study the effects of the firefighting chemical on airmen and other troops who may have used it.

"The Air Force's goal is to ensure that any health condition sustained by our Airmen pursuant to the support of an Air Force mission is properly cared for and compensated," the service's surgeon general said in a statement responding to Gazette questions. "We encourage our airmen and veterans to seek care for any health condition they believe is connected to chemical exposure during service."

Former Air Force firefighter Jeff Warrick of Delaware said he used the foam for years with no warning of its risks.

During training exercises, his bunker gear was soaked in the foam.

"We bathed in it," he said.

Now he worries the foam that was so effective in extinguishing burning fuel could be connected to a tumor he had on his genitals and other health conditions. Doctors have few answers for him, he said.

"Oh, yeah, it does the job," Warrick said. "We just didn't realize what it might be doing to us."

'I do feel like a lab rat'

Studies show the first laboratory rats died from exposure to a perfluorinated compound in the 1960s.

More studies have found rats in the experiments had pups with low birth weights. Some rats suffered liver and kidney damage. Some contracted cancers.

According to Air Force documents obtained by The Gazette, a study by the service's research laboratory in 1979 linked the chemical to damaged "thymus, bone marrow, stomach, mesentery, liver, and testes in the male rats."

The service ordered a study published in 1981 that found the chemical could cause damage to female rats and their offspring, including low birth weight.

In the second study, pregnant female lab rats died when exposed to high doses of the chemical. The researchers wrote that the 1979 study confirmed exposure danger for male airmen, "but did not depict the potential hazard in Air Force women," necessitating the follow-up.

That study also says the Air Force was a leader in studying the toxicity of firefighting foam, with the only literature on the subject coming from the service's laboratory at Wright-Patterson Air Force Base in Ohio.

More Air Force studies came after that, with several in the 1980s and 1990s.

Despite alarming findings, the service kept using it, leading it to seep into drinking water in Colorado and around the globe.

In response to Gazette questions about its studies, an Air Force spokeswoman questioned the validity of the service's own scientific work in the 1981 study of the foam.

"We were able to do an initial review of the report you provided and determined that specific chemical was never used in our Aviation Fire Fighting Foam and was only used for the purpose of that study," spokeswoman Laura M. McAndrews wrote.

The study, though, says the chemical tested was a perfluorinated acid that Air Force scientists called "structurally related to a surfactant agent used in fire retardant foams by the Air Force."

Some firefighters who used the foam are angered by all the science they weren't told about.

"I do feel like a lab rat," admitted former Peterson Air Force Base Fire Chief Steve Kjonaas, who used the foam frequently during a 28-year Air Force career that was cut short by prostate cancer in 2007. He worries that his condition was caused by exposure to the foam's active ingredient - perfluorooctane sulfonate.

Bridgette Swaney wonders if the Air Force's science experiments of 1979 and 1981 played out in her own house more than 30 years later.

Over the past year, Swaney has raised rats in her split-level home off Southmoor Drive in Widefield's water district, feeding them tap water now known to be laced with the firefighting foam chemical. Several of the black and white rodents grew massive tumors, even as pups. Swaney, 31, also has faced ailments since moving to Widefield six years ago, including high cholesterol and worsening thyroid issues - two possible symptoms of firefighting foam exposure.

If the Air Force knew perfluorinated compounds could harm rats at least 37 years ago, then the Air Force should pay, Swaney said.

"It's really frustrating - it really, really is," Swaney said. "It's frustrating to know that my 4-year-old has drank this water her entire life. I drank the water the entire time I was pregnant. We're just expected to accept it."

A different view

The Air Force's view of the chemical's history is different.

The Air Force's top expert on the toxic chemical said the military didn't really understand the danger of such chemicals, also known as PFCs, until 2009.

"So in 2009, taking this through 2009, EPA then issued a provisional health advisory for PFCs. And I think this is a real key point here is that's when they issued that provisional health advisory," explained Daniel Medina, a civilian at the Air Force's Civil Engineer Center in San Antonio.

While the Air Force studied the firefighting foam's toxicity, Medina said, the service would not change its chemical policies without direction from the EPA.

"Right, so again that's where we'd look at the regulations that EPA and in this case the health advisories put out there to look to defer to that," he said.

The toxic chemical in the firefighting foam and its sister chemical, a key ingredient in Teflon, were born out of the chemistry revolution after World War II.

The firefighting foam is a Vietnam-era military invention patented by the Navy's Naval Research Laboratory as an alternative for battling aircraft fires aboard carriers.

The foam is credited with saving thousands of lives from shipboard and fuel fires. It seems almost miraculous for stopping burning fuel, forming a Jello- like barrier between the flames and the fuel that quickly stops the blaze.

"What it does is it helps you against flammable liquid fires," explained the Air Force's fire chief, James E. Podolske Jr.

Days after Podolske was presented to The Gazette as a spokesman on the issue, he was indicted on charges brought by the Justice Department for procurement fraud, alleging he "knowingly disclosed defense department contract bid or proposal information to give a competitive advantage to a corporate defense contractor." He was also accused of pocketing $133,000 in donations related to a charity golf tournament, the Justice Department said in a news release.

"Sometimes you may spray the foam and eliminate the potential for ignition from vapors; it'll keep from reignition, even if firefighters walk through it, because it forms that vapor barrier back over it," Podolske said in his interview with The Gazette.

Once the foam gets into the environment, though, it's not going away.

Like fuel, the chemical's backbone is a long string of carbon atoms - eight of them. Attached to those carbons is fluoride, forming a remarkably stable concoction using one of the strongest chemical bonds known to science. Perfluorinated compounds in the environment could outlast the sun before breaking down in a time frame normally precise scientists like Colorado School of Mines chemist Christopher Higgins can only describe as "geologic."

Concerns about the firefighting foam were serious enough that a 1991 environmental assessment of Fort Carson by the Army Corps of Engineers concluded, "Firefighting operations that use (the foam) must be replaced with nonhazardous substitutes."

In June, Gardner sent a letter to Air Force Secretary Deborah Lee James asking the Air Force to publicly release all information it possessed on contamination in the Pikes Peak region. The senator, though, hadn't been made aware of the repeated Air Force studies into the health risks of the foam.

"We have to have the measures taken to assure public safety," Gardner told The Gazette. "We need the commitment of the Air Force to do a full reckoning of the documents you have cited.

"This isn't something that can be swept under the rug," Gardner said. "It has to be met with the full faith and credit of the United States."

Routine use of foam for years

Even as the Air Force studied the risks of its firefighting foam, firefighters at Peterson Air Force Base sprayed the foam over and over onto the ground as practice for putting out airplane fires.

Using two unlined pits, firefighters dumped pools of jet fuel on the ground and lit it - simulating the perils of an airplane crash. The flames were extinguished by coating the pond in foam, said Kjonaas, the former base fire chief.

The practice at those pits continued until the early 1990s, when the Air Force completed a lined pit for those exercises, sending the remnants into the base's sewer system. Scientists say a sewer system, though, is unlikely to remove the toxic firefighting chemical from water.

The foam was used routinely until 1999, when a propane-and-water system was installed.

The exact number of times the training was conducted at Peterson has not been released. Kjonaas said training was routine at Peterson during his time as chief, which ended in 2007, with foam being used as often as quarterly.

Until last year, the Air Force also put a small amount of foam on the ground for a daily check to make sure the foam system on fire trucks worked properly, said Podolske, the Air Force's top firefighter.

"Spray testing at Fire Station No. 1 is done on the concrete ramp during good weather and at the volleyball court during inclement weather," a report on contamination at Peterson says.

That daily testing has stopped.

"Because of the environmental concerns and the health hazard concerns right now while we were working this, we put out a cease and desist," Podolske said.

One of the largest known local uses of the foam in recent years came on Dec. 23, 2010, when a single-engine plane crashed just north of a Peterson runway, killing the pilot and his passenger. A report on contamination at Peterson says "at least 100 gallons" of firefighting foam was sprayed to extinguish the wreckage.

Last week, Peterson acknowledged additional recent discharges of the foam, including a 2013 training exercise and two leaks from firetrucks this year.

On Tuesday, Brooks, the environmental officer, said that someone had turned two valves and operated an electric switch to send 150,000 gallons of foam-contaminated water - the equivalent of more than 16 gasoline tankers - into the Colorado Springs Utilities' sewer system. The base had not sampled the wastewater to determine the level of its contamination.

Asked whether the release could have been intentional, Brooks said, "That's an option."

The incident, which remains under investigation, was discovered by the Air Force on Oct. 12 and announced to the public six days later.

Asked what he would do to clean up the new release, Peterson's Brooks said there was little he could do because the chemical had left his base.

Pattern of contamination found

Industry has found plenty of uses for the same sturdy chemical in firefighting foam as well as similarly structured compounds. Most commonly, they've been used to treat carpets as a stain fighter. They were also used in nonstick cookware and at one time were used in food wrappers.

Those manufacturers harbored concerns about such chemicals decades ago.

DuPont issued an internal memo raising health concerns in the early 1960s, according to a Harvard University report. A study in the 1970s on the chemical's effects on monkeys' immune systems went unpublished, though other studies in the 1980s and 1990s deepened health concerns, the Harvard report said.

But the firefighting foam, so commonly sprayed on the ground in large quantities, is "likely the most important way in which we have contaminated water supplies around the globe with fluorochemicals," said Higgins, the School of Mines chemist.

A recent study by Higgins and other researchers found that one of the greatest predictors of contaminated water systems in the U.S. is their proximity to a military firefighting training area that used the foam, along with manufacturing sites and wastewater treatment plants.

The Air Force is studying an estimated 2,800 fire training areas and other places the foam was sprayed at present and past installations around the world. That includes a half-dozen sites at Peterson Air Force Base and the Colorado Springs Airport.

Results of the Colorado Springs study are not due until March.

Near Fairchild Air Force Base outside Spokane, Wash., researchers found how the firefighting foam chemical is passed through the ecosystem, with each species accumulating more of the toxin as it moves up the food chain.

The study, by the Washington State Department of Ecology, focused on ospreys, the predatory birds that rule lakes and rivers around the Spokane base.

"The osprey come back in the spring, and they just eat a ton of fish," said Callie Mathieu, a research coordinator for the agency.

The fish swim in Medical Lake, near the base, where a sewage outflow has pumped the firefighting chemical. Ospreys pick up more of the chemical with each fish they consume.

"When they lay their eggs a month later, they pass on that contaminate burden to their eggs," Mathieu said.

The concept is the same for humans. When the EPA issued its latest advisory in May, Colorado health officials said women who are pregnant or breastfeeding or bottle-feeding infants may want to avoid their water. That's largely because infants are the most susceptible to the dangers such chemicals pose. The threat includes miscarriage and low birth weight, a key factor in infant mortality.

That EPA advisory warned that water could be harmful if such chemicals surpassed more than 70 parts per trillion - significantly lower than an advisory issued in 2009. Speaking again to the power of the foam, the 3 percent chemical with 97 percent water solution used to fight fires is 300,000 parts per trillion. A tablespoon of the chemical in 20 Olympic-sized pools would easily exceed the EPA threshold.

Contamination in wells in the Security, Widefield and Fountain areas ranged from just a couple of parts per trillion to 2,000 parts per trillion, nearly 30 times the EPA's advisory level, tests this year showed. The average reading of 108 groundwater test sites was 164 parts per trillion, according to the Colorado Department of Public Health and Environment, more than two times the EPA's health advisory level. The median for those groundwater tests was about 115 parts per trillion.

Philippe Grandjean, who teaches at Harvard and the University of Southern Denmark, isn't satisfied with current limits. He wants the EPA to further limit exposure to an infinitesimal level - 1 part per trillion, because such chemicals stay in the body for years.

"These compounds are much more toxic than we thought," Grandjean said.

'A lot of unanswered questions'

The military has yet to face any lawsuits stemming from its use of the chemical in Colorado. For the most part, federal agencies are immune from liability.

Some local politicians have praised the military for its actions to clean Pikes Peak region drinking water while refusing to comment on how the water got contaminated.

"The Air Force is going above and beyond in their willingness to be a good community partner and neighbor with their multi-million dollar response commitment to this particular issue," Colorado Springs Republican U.S. Rep. Doug Lamborn, a member of the House Armed Services Committee, said in a statement. "The money and time they are investing will go a long way toward addressing the needs of the citizens of our region."

Several firefighting foam manufacturers and other companies making perfluorinated compounds have been sued.

Manufacturers of certain perfluorinated compounds have faced lawsuits since at least the late 1990s, and a landmark settlement in one case led to Dr. Brooks' research project that collected blood samples from 69,000 people in the mid-Ohio Valley, a region east of Cincinnati centered on Parkersburg, W.Va.

Brooks said the study revealed many health problems, especially high cholesterol stemming from such chemicals. Worse, he said, the health impacts can last a lifetime because the human body can't get rid of them.

Two federal lawsuits seeking class-action status for Security, Widefield and Fountain residents have been filed against 3M and several other companies that made the foam and supplied it to Peterson Air Force Base. They seek money for local medical studies and damages.

A spokesman for the law firm representing 3M, which phased out production of the chemical in 2002, said last month that the company will "vigorously" defend itself against the lawsuits, just as it has in the past.

The chemical that 3M included in its foam is similar - though slightly different - from what DuPont made. The EPA, however, lumped them together in its May advisory, citing similarities and health concerns about each.

A resolution to the lawsuits might take years.

For now, the people receiving contaminated water in their kitchen taps have been left with the tab.

Swaney, whose rats developed tumors, estimates having spent about $30 a month on bottled water for her family. But her pets still use the toxic water.

"It's hard - it's hard, especially when you have pets," Swaney said. "I do love my dog. But can I afford to spend the money to make sure my dog drinks bottled water? Not so much."

Samantha Beckner, 37, said she spends $30 to $40 a week on bottled water, which she stuffs into her children's backpacks each day for school.

The worst part is grappling with the uncertainty their tap water brings.

She recently underwent a scan to determine if she had the first stages of breast cancer. The test came back as benign. Her family is often sick with cold and flu-like symptoms.

Did the water cause it? She can't say for sure.

"We have never been as sick as we have been since we have lived in that house," Beckner said.

The one certain effect from the contaminated water will be higher water bills for many residents in 2017, water district managers say.

Combined, Security, Widefield and Fountain water officials have spent millions of dollars purchasing additional, cleaner water from other agencies or to widen their existing pipes and install new ones that bring in contaminant-free water from the Pueblo Reservoir or both.

Permanently disconnecting from the Widefield aquifer is infeasible, water district leaders say, because too little water exists elsewhere to meet demand without skyrocketing costs. As a result, the water district might build new treatment plants to filter the chemicals from their well water.

Those projects, however, typically cost millions of dollars and take years to complete.

Tedy Stockwell, 61, is furious she has been left to pay for a problem someone else created.

She moved to Widefield after the Black Forest fire in 2013 to improve her family's health. Her house survived that blaze, but her children had trouble breathing from the smoke damage.

She and her husband have since had cholesterol issues, and she plans to visit the doctor to find out whether the water had anything to do with it.

"There's just a lot of unanswered questions," Stockwell said.

Little has been left unaffected, Stockwell said. She invested in a garden, complete with special soil, seeds and fertilizers. She now questions whether she should grow anything in that soil and whether the water she used on it turned her vegetables toxic.

She paid nearly $100 last month for bottled water and $65 for her tainted tap water.

And knowing the chemical is still being used is "ridiculous," she said. "There has to be a stopping point."

But long after the Air Force follows through with its plan to destroy its remaining stocks of firefighting foam, a toxic legacy will remain for those who drank water from contaminated wells, Dr. Brooks said.

"If you are 60 years old, you can't live long enough to get down to a level that it is not going to bother you."