Soon, other family members became ill. Her brother-in-law contracted fatal kidney cancer. Her father-in-law developed esophageal cancer. Then her 32-year-old son began having severe kidney problems.

It wasn’t until 2016 that scientists tested the tap water they had been drinking and found it was contaminated with man-made chemicals known as perfluorinated compounds, part of a family of chemicals called PFAS. The chemicals were traced to firefighting foam from a nearby military airfield, one of hundreds of Pentagon bases nationwide that for decades may have contaminated drinking water used by tens of thousands of people.

“We had no clue,” said Rash, 58.

The role played by PFAS in the family’s illnesses is not known. Studies have shown a link between the chemicals and a range of health problems, including an elevated risk for some cancers, but they have not established a clear cause-and-effect relationship.

Rash’s family history of illnesses is common in Fountain, a Colorado Springs suburb flanked by mountains and military bases. And the scientific uncertainty about how much risk residents face has only worsened the anxiety many feel, as Fountain and surrounding towns have become a center of the growing national furor over the possible health effects of ingesting PFAS.

Congress is trying to expand regulation of the chemicals. Earlier this month, the House voted 247 to 159 in favor of a bill requiring the Environmental Protection Agency to designate PFAS as hazardous substances, which would free up funds for the cleanup at contaminated sites.

But the Trump administration has threatened to veto the bill, saying in a Jan. 7 statement that such a move would force high compliance costs on businesses and states, and that the EPA, not Congress, should make the decision.

PFAS chemicals — used in food packaging, waterproof fabrics and nonstick pan coatings — have been found in the water and soil in more than 1,300 communities in 49 states, including California.

In October, The Times reported the results of California’s first test of PFAS in drinking water. Officials sampled 600 wells throughout the state and found that the two most common PFAS compounds were detected in 86 water systems that serve up to 9 million Californians.

Beginning this month, a new state law requires utilities to inform customers if PFAS are found at any level in their water. It will also force water systems to either shut down wells that test over the federal health advisory level or notify customers of the contamination.

Fountain offers a preview of the battles California could be facing as it begins a years-long effort to track the scale of the state’s PFAS contamination.

California has at least 21 current and former military bases — more than any other state — where testing by the military revealed elevated levels of PFAS in the soil and groundwater, The Times reported in October.

In Fountain and two nearby towns, Widefield and Security, military facilities were also the source of the contamination.

The communities are now in year five of a water safety crisis that stands as a case study of how difficult it is for residents to get clear information about — much less compensation for exposure to — a chemical that has yet to be federally regulated but is considered a health risk to humans by many scientists and environmental advocates.

Residents have filed suit, testified in Washington and nevertheless remain deeply disillusioned by what they describe as the grudging, sometimes evasive, government response.

“This community wants answers. They want to see action on the regulatory issues,” says Tyler Cornelius, a Colorado College professor and a local clean water activist. “They continually get the short end of the stick.”

The contamination near Colorado Springs was traced to Peterson Air Force Base, 12 miles north of Fountain, where firefighters for decades sprayed PFAS-laden foam that seeped into an underground aquifer that supplies the area’s drinking water, Pentagon testing records show.

“The Air Force believes Peterson AFB is a likely source of at least some of the PFAS … contamination that impacts the Widefield aquifer, which provides water for Security, Widefield and Fountain,” said Mark Kinkade, an Air Force spokesman. “The Air Force does not accept responsibility for unknown or undefined potential health effects, particularly when the cause of those effects are not identified.”

The revelation has strained the community’s relationship with the military, a major employer in the area; as many as two-thirds of the residents are military retirees or active-duty families, according to officials in Fountain.

“We’re just looking for justice and accountability,” said Mark Favors, a former Army reservist who grew up in Colorado Springs and has seen 16 of his family members contract cancer. Four of those died of kidney cancer, including his father.

Before 2016, residents and local officials didn’t know they had been drinking contaminated water, perhaps for decades. The EPA, which had ordered nationwide testing for PFAS, made public the results of its testing in May.

Fountain tested at twice the EPA health advisory level, which is nonbinding. Widefield came in at more than three times higher. It was even worse in Security.

At one drinking well in Security, the PFAS level reached 1,370 parts per trillion — nearly 20 times higher than the EPA’s health advisory level of 70 parts per trillion.

Among the three towns, 53 municipal and private wells — which provide most of their water — tested above the EPA standard. As many as 70,000 residents may have been exposed to the chemicals, local officials said.

In Fountain, officials shuttered four of the town’s large wells during the high-use summer months. The move reduced the water supply by 20%, and the city scrambled to replace it with uncontaminated water from nearby reservoirs, said Curtis Mitchell, Fountain’s utility director.

To pay for the extra water, and to build new pipelines to guarantee enough future supply, Fountain had to raise water rates by 5.4% in 2016, then 4.3% the next year.

The effects were more severe in Security, where the water supply was dependent on two dozen groundwater wells — all of which had been contaminated with PFAS.

“Literally overnight, none of our wells were compliant,” said Roy Heald, manager of Security’s water and sanitation districts. “People thought they were being poisoned.”

People in Fountain Valley reacted with fury. More than 500 people showed up at a meeting where officials from the EPA, Air Force and local communities insisted they were doing all they could to clean the water.

Pregnant women or those who were breastfeeding should consider drinking bottled water, a Colorado Department of Public Health and Environment official said. According to local news accounts, when asked whether others were at risk, officials said federal regulators were continuing to study the health effects.

According to the Centers for Disease Control and Prevention, some studies of PFAS exposure in humans have shown that the substances can increase the risk of cancer, affect the immune system, increase cholesterol levels or affect child development, among other things. But the scientific effort to understand possible health dangers is ongoing.

In September, the agency launched an investigation into the health effects of drinking PFAS-contaminated water. The study includes 8,000 adults and children at seven locations around the country, including El Paso County, which includes Fountain, Security and Widefield. The findings are not expected to be made public for five years. The study will not look at cancer rates, which the agency said would require studying a larger population.

A state health report published in June 2016 that examined cancer rates in the contaminated areas of the county did little to allay concerns. Kidney cancer rates were found to be 16% higher in the three communities than in the unaffected areas of the county, while bladder cancers were 34% higher and lung cancer was 66% greater.

The report did not attribute the higher cancer rates to tainted water, citing a lack of data. Instead, it suggested that rates of smoking and obesity may be responsible.

“We don’t know a lot about health effects” of PFAS, the report by Colorado’s Department of Public Health and Environment said. “There is inadequate information available to make definitive causal associations between drinking water exposures” and cancer rates.

Residents saw the findings as a slap at a community that is less affluent than other areas near Colorado Springs.

“They said we’re low-income and eat a lot of fast food — that’s the cause,” Rash said.

The report’s authors said they did not intend to dismiss residents’ health worries.

“We care about them and their health,” said Kristy Richardson, a state toxicologist who conducted the study. “While relatively little is known about the specific human health effects of these chemicals at levels that were found in their drinking water, the concerns are entirely valid.”

Others saw the conclusions as a way to shift responsibility away from state officials and the military.

“My reaction was, ‘Our voices are not being heard,’” said Liz Rosenbaum, who formed the Fountain Valley Clean Water Coalition to press for state and federal assistance, including blood testing and health monitoring of residents.

For local governments, the immediate need was to install temporary filters to remove the chemicals — an expense that the Air Force agreed to pay.

Shutting off all the wells at once would have left Security unable to meet even minimal daily water needs. Heald, who oversees the city of Security’s water quality, decided to rotate which wells were in service each day. That meant some customers were still drinking tainted water, but not every day.

Some residents stopped using tap water altogether. A food bank started distributing free bottled water. Widefield set up a bottled water distribution station, where residents could take up to 10 gallons a week for free from a yellow fire hydrant fed by an untainted nearby reservoir.

The source of the contaminants was clear to city officials: The closer the wells were to Peterson Air Force Base, the higher the PFAS levels.

One of the specific PFAS chemicals found at elevated levels in the water in Fountain, Widefield and Security was perfluorohexane sulfanate, a key component of firefighting foam.

Former firefighters at the base told Air Force investigators that hundreds of gallons of foam had been sprayed in regular training exercises and in weekly tests of the equipment, according to a report about PFAS contamination at Peterson last May and made public by the Air Force.

The runoff was funneled into sewers or soaked into the ground, filtering into the aquifer beneath Peterson that supplied much of the drinking water to communities south of the base.

Air Force officials initially offered $4.3 million for new filter systems to all three communities, calling it a “good-neighbor gesture.”

At two of Fountain’s wells, the military paid for a system that allows water from the ground to be piped through newly installed 20-foot-high tanks containing granular carbon to remove the chemicals.

But the military’s help came with restrictions. The Air Force would not pay the millions of dollars each year required to operate the filter systems, replace worn out filters or regularly sample the water. Nor would they initially agree to build treatment plants, the permanent solution favored by local officials.

In Fountain, officials estimated it would cost as much as $7 million to overhaul its water system.

Mitchell and other local officials flew to Washington in late 2017 to ask Air Force officials at the Pentagon to pay the bill. They also enlisted Colorado’s congressional delegation, including Sens. Michael Bennet and Cory Gardner, who sent letters to the Air Force and pushed through legislation authorizing the military branch to reimburse the towns for costs they had already incurred.

In March 2018, the Air Force agreed to pay for treatment facilities for all three communities. The project is underway and is expected to be completed this year. Air Force officials, however, would not agree to reimburse the three communities for the annual cost of operating the plants.

Air Force officials told The Times that they had to complete a formal investigation of the extent of the contamination before they can authorize further payments, a process that is ongoing.

“The Air Force is focused on the installation of the treatment systems and has not made a determination on any potential future operation support,” said Kinkade, the Air Force spokesman. He added that federal laws give the military “limited authority” to provide additional funds once Fountain, Security and Widefield wells are producing drinking water with PFAS levels that fall below the EPA advisory level.

Officials in Security sued the Air Force in March for $17 million in cleanup costs, alleging that spraying of firefighting foam at Peterson Air Force Base was negligent and violated its own hazardous waste disposal policies.

Hundreds of residents also sued the foam manufacturers.

But the prospect for the lawsuits, which have been combined with 120 other PFAS-related suits into class-action litigation in federal District Court in South Carolina, is unclear. The Air Force claims that federal sovereign immunity shields it from such legal challenges. U.S. District Judge Richard Gergel is reviewing preliminary motions in the case. A determination of whether the Pentagon, or manufacturers of the foam, are liable for contamination in those communities could be years away, experts say.

The dispute has damaged the goodwill that Peterson Air Force Base — a source of jobs and dollars for the economy — had with the community, residents say.

“Through this process, people have realized they can’t trust certain aspects of what they hear from the government,” said Cornelius, the Colorado College professor.

Many residents point to evidence that the Pentagon was alerted decades ago that the chemicals in firefighting foam could be harmful.

Ft. Carson, a sprawling Army base also near Fountain, halted its use of toxic firefighting foam in the early 1990s after the Army Corps of Engineers warned that PFAS was hazardous, according to internal Defense Department documents obtained by the Environmental Working Group, a research organization that has pushed for strict PFAS regulations.

Firefighters at Peterson stopped using the toxic foam for training in the early 1990s, though it is still used in case of fire emergencies, according to a 2019 Air Force report.

In 2015, the Air Force deemed PFAS a toxic substance.

Today, more than 200 people from the three areas are participating in a study funded by the National Institutes of Health that has found PFAS levels in their bloodstreams well above samples taken from the U.S. population as a whole.

Preliminary results released in December 2018 showed that the median PFAS level in the bloodstream of those sampled was 14.8 nanograms per milliliter, 10 times higher than the national average.

The PFAS levels were “quite a bit higher than I expected,” said Anne Starling, a researcher with the Colorado School of Public Health, one of the study’s authors.

Favors, the former Army reservist who has emerged as a spokesman for the community’s grievances, testified at a congressional hearing in November, breaking into tears at one point as he recounted his family’s history of illnesses and sudden deaths. His mother worked for four decades at Peterson, one of many relatives who served in the armed forces or were employed by the Defense Department.

“Back in Colorado, their loved ones were being poisoned by Peterson Air Force Base dumping toxic chemicals into Fountain Creek,” he told the House Oversight and Government Reform Committee. “We can’t even get a transparent investigation.”

Favors testified alongside actor Mark Ruffalo, the star of “Dark Waters,” a movie account of an Ohio attorney’s lawsuit alleging DuPont chemical company exposed employees and communities near its factories to PFAS contamination.

Actor Mark Ruffalo listens to Mark Favors, a former Army reservist who grew up in Colorado Springs and has seen 16 of his family members contract cancer. Favors testified at a congressional hearing in November.

(Kirk McKoy / Los Angeles Times)

But Favors’ real-life story prompted pushback from Republicans, who warned it would be a mistake to impose overly strict federal controls on PFAS and would lead to expensive liability claims on manufacturers and the Pentagon.

“PFAS chemicals have helped many people’s lives,” and any regulatory steps “need to be based on science,” Rep. James Comer (R-Ky.) told Favors, though he added that “if any families have been poisoned intentionally by corporate America,” they should be compensated.

Activists in Colorado say that is exactly what they are owed. But many are tiring of the battle.

When the Fountain Valley Clean Water Coalition held its November meeting in the back room of a brewpub in Fountain Valley, only 20 people showed up. Two EPA representatives present said the agency was weighing restrictions on two of the most common types of PFAS and would issue regulations soon.

The reaction of residents reflected their frustration and cynicism about the military: The Pentagon would find a way to block the regulations, one told the EPA representatives.

Janice King, who lives just outside Fountain and drank backyard well water for two decades, came away fearful and confused. She’s stopped using the water for drinking and cooking.

Tests run on her in 2018 revealed an elevated PFAS level of 12 nanograms per milliliter in her bloodstream, well above the national average, King says. But no one can tell her if drinking from the well all those years could cause future illnesses.

“I’ve lived here for 21 years, and I would really like to see more concern by local and national officials,” she said. “As Americans we just kind of assume that somebody, somewhere, is regulating our drinking water to ensure it is safe.”