Workers at two Tennessee Valley Authority power plants in East Tennessee say they are continuing to be exposed to fly ash dust and flue gas — both toxic substances — without masks or respirators, an ongoing USA TODAY Network-Tennessee investigation reveals.

USA TODAY Network-Tennessee has been investigating for two years the treatment of workers who cleaned up TVA’s massive coal ash spill — the nation’s largest — and current working conditions.

Fly ash is the term for the dry form of coal ash, the byproduct of burning coal to produce electricity. Coal ash contains concentrated forms of at least 26 toxins and heavy metals, including arsenic, lead, lithium, mercury, radium and sulfate, according to a Duke Energy materials safety data sheet.

The news organization has now obtained videos and photographs that show what workers say is coal ash dust on the dashboards and floorboards of enclosed cab heavy equipment machinery at TVA Bull Run Fossil Plant in Anderson County and on the floors and walls in enclosed work areas inside TVA Kingston Fossil Plant in Roane County.

Those videos and photographs also show what workers say is fly ash dust escaping into the air at Bull Run in an area of the plant near a public park in February, and flue gas — a toxic substance that TVA must scrub clean before emitting — escaping into the air at Kingston.

Workers' claims they were exposed to toxic coal dust led to a lawsuit by 73 contract workers or their survivors that claims they were poisoned during a cleanup that began in 2008 because they say weren't adequately protected. A federal judge has ordered the contractor — Jacobs Engineering — and the workers to try mediation in an attempt to settle the case.

Jacobs says it thinks the rulings that led to the mediation order are incorrect and plans to appeal, attorney Theodore J. Boutrous Jr. wrote in a statement released last month.

"The trial in the first phase of this case was fundamentally flawed and unfair, and it should not stand," Boutrous continued. "There has been no finding of liability in these cases, and Jacobs stands by the quality of its work in assisting TVA with the management of the Kingston cleanup. Jacobs takes pride in working on some of the world’s toughest challenges and in protecting the safety of all those who work on its projects.”

Chief U.S. District Judge Tom Varlan has said in court that Jacobs does not have the automatic right under the law to appeal his ruling or the jury's verdict.

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Protecting coal ash from scrutiny

USA TODAY NETWORK-Tennessee has been investigating for two years worker conditions during the cleanup of TVA’s record-breaking coal ash spill at its Kingston Fossil Plant in Roane County in 2008. The news organization has since expanded that probe to include current worker conditions and the safety of communities surrounding both the Kingston plant and TVA Bull Run Fossil Plant in Anderson County.

TVA insisted a decade ago — when a dike gave way at the Kingston Plant and 7.3 million tons of coal ash smothered 300 acres in Roane County — that coal ash was safe. TVA told the community and workers coal ash contained only a handful of substances, with silica being the worst of the lot.

Independent testing by Duke University and others revealed, though, that coal ash is a toxic stew of dangerous chemicals and metals. TVA now concedes in material data safety sheets obtained by USA TODAY NETWORK-Tennessee that coal ash contains more than two dozen toxins, including arsenic, cadmium, lead, mercury, radium and selenium.

TVA continues to insist coal ash is safe and that workers aren’t necessarily endangered by toiling in it without masks or respirators and Tyvek body suits, the same claim Jacobs Engineering made last year when it unsuccessfully tried to fend off the first phase of the ongoing federal lawsuit filed on behalf of Kingston coal ash disaster relief workers.

TVA put Jacobs Engineering in charge of cleaning up the spill and keeping workers and the community safe while doing it.

Disaster relief workers — 900 at the height of the spill cleanup — were immersed in the Kingston ash without masks or respirators and Tyvek body suits for as much as 60 hours a week for months at a time for some and years for others. Some workers were employed at the site for as many as seven years.

Jacobs’ safety managers told workers they could safely eat a pound of coal ash daily, a statement not scientifically supported. Jacobs officials have said the statement wasn't made to be taken literally, according to court testimony.

The investigation also revealed evidence Jacobs' managers denied them more extensive protective gear, destroyed boxes full of protective dust masks and threatened to fire them if they insisted on protection. At least one worker maintains he was terminated by a TVA supervisor after his doctor ordered respiratory protection.

A jury in U.S. District Court in November sided with workers in the first phase of their lawsuit. The jury ruled Jacobs Engineering breached its contract with TVA and its duty of care to protect the workers and that breach was capable of causing the illnesses the workers say they suffer. A second phase of the trial must be held to determine whether Jacobs actually caused the workers' ailments, which Jacobs denies.

TVA is still doing business with Jacobs — to the tune of at least $200 million in new contracts awarded since the October trial — and Jacobs still has oversight authority over contract laborers at both the Kingston and Bull Run plants.

And current workers told USA TODAY Network-Tennessee they are still being exposed to coal ash — without mandatory masks or respirators and Tyvek body suits — at both the Kingston and Bull Run plants and fear reprisals for seeking protection.

Workers still being exposed

The USA TODAY Network-Tennessee has obtained videos and photos of worker conditions at the Kingston and Bull Run plants, conducted dozens of interviews, reviewed relevant OSHA standards and obtained worker safety manuals in the past two months.

That investigation has revealed coal ash is piling up inside vehicles and the plant.

Workers say they are not provided boot washes or other decontamination facilities to clean coal ash from their boots, clothing and skin while working in coal ash. Jacobs didn’t provide that for disaster relief workers, either.

Heavy equipment operators are working inside enclosed cabs without breathing protection and surrounded — on the floorboards, the dashes and the windshields — by coal ash dust. The dust is made up of tiny particles that embed deep in the lungs and can’t be coughed out, the EPA says. Long-term exposure to fly ash dust is linked by the EPA to a host of fatal and chronic illnesses.

After USA TODAY Network-Tennessee first published a series of stories in 2017 about the treatment of the disaster cleanup workers, TVA posted signs that warned fly ash “may cause damage to lungs after repeated/prolonged exposure."

The signs said workers toiling in enclosed spaces where fly ash is present were now being required to wear masks while working inside the indoor silos.

“Do not breathe dust,” the signs warn. “Get medical advice/attention if you feel unwell.”

TVA spokesman Scott Brooks did not answer questions about why such respiratory protection is not now being required for workers who labor inside enclosed truck cabs or inside areas of TVA's plants where coal ash is present.

Brooks said the enclosed cab vehicles at both TVA plants are not scrubbed of ash as a routine procedure on a daily basis. The air filters are checked and changed on a schedule according to the owners manual. They are not routinely inspected for coal ash dust.

Workers have told USA TODAY Network-Tennessee that coal ash dust typically coats the inside surfaces, including the windshield, of the vehicles.

TVA says it is up to the workers — and contractor bosses like Jacobs — to report dust “concerns” inside those vehicles. Workers who have complained were given brushes by their contractor bosses to sweep out the cabs, according to interviews.

USA TODAY Network-Tennessee has documented multiple instances in January and February in which workers inside two separate units at the Kingston plant were working without masks or respirators and Tyvek body suits amid layers of dry coal ash on the floors, walls and ceilings around them. Workers also were seen working without masks or respirators or Tyvek body suits in areas where they say flue gas was escaping into the air before the cleansing process was complete.

TVA relies on contractors to choose gear

TVA leaves it up to contractors like Jacobs to decide what protective gear to provide workers. Jacobs typically serves as project manager over a web of TVA-favored contractors.

Jacobs’ safety managers have testified masks or respirators and Tyvek body suits are unnecessary for coal ash workers unless data shows exposure levels above those set by OSHA, and, so, protective gear is not provided as a matter of course.

TVA used that same language in its response to USA TODAY Network-Tennessee’s questions on worker safety at Kingston and Bull Run.

“It is the responsibility and requirement of employees to wear appropriate personal protective equipment, including respiratory protection, when sampling or historical data supports exposures to employees in excess of the permissible exposure limits as outlined by OSHA,” Brooks wrote in an email. “At such time, respiratory protection is provided.”

Brooks wouldn’t say who provides that “sampling or historical data,” how it is obtained and whether workers are advised of high exposure levels.

TVA says the Environmental Protection Agency independently reviews the results.

TVA to workers: Protect yourselves

OSHA requires employers to provide workers testing data and to explain the dangers of their jobs using language the workers can understand. Neither TVA nor Jacobs did that during the cleanup, workers testified.

OSHA did not monitor worker safety at the cleanup, according to EPA records, and has declined requests for interviews about that.

Workers interviewed by USA TODAY Network-Tennessee said they have never been outfitted with monitoring devices to test their exposure levels while working inside the plants, inside enclosed cabs and in the various ash storage facilities at both plants.

Brooks did not respond to questions about how TVA determines when workers are being exposed to dangerous levels requiring respiratory protection. OSHA leaves it up to TVA to test exposure levels. TVA leaves testing up to contractors, a review of its own public records shows.

Brooks said it is ultimately up to the workers to protect themselves and police their bosses.

“TVA has a Safety Program in place which requires employees to report unsafe working conditions and to intervene when unsafe working conditions or behaviors are witnessed,” “Brooks wrote.

Brooks said workers have no reason to fear “reprisal” for complaining. Sworn testimony in depositions and the federal phase one trial as well as a video of a Jacobs' safety manager obtained by USA TODAY Network-Tennessee showed cleanup workers were threatened with layoffs when they complained.

“TVA has a Safety Program in place that prohibits reprisal for raising safety concerns or requesting protection from workplace hazards,” he said.

That program is the same one in place during the cleanup.

Jacobs says it follows TVA's safety protocols.

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Protections differ among contractors

At least one contractor not under Jacobs’ site control — G&A Environmental Contractors Inc. — is outfitting its workers in respiratory and full-body protection during its work for TVA.

USA TODAY Network-Tennessee verified at least one instance in February at the Bull Run plant in which a group of workers, including G&A staffers, were being exposed to fly ash dust at the same time and in the same location. Only the two G&A employees were wearing protective gear — one was wearing a mask, and the other a full respirator, and both were clad in body suits.

Coal ash operations at the two plants involve both TVA employees and contractor laborers. GUBMK Constructors provides most of those contractor laborers through contacts with union halls. Workers often perform various jobs under the auspices of varying contractors, so some workers say the line of authority for making complaints and getting protective gear is not always clear.

During the early years of the Kingston disaster cleanup, GUBMK never mentioned in its worker safety manual the need for protective gear for workers exposed to coal ash nor did it warn workers of the toxins in coal ash. GUBMK did not return phone calls for comment.

GUBMK now is warning workers about the dangers of coal ash in its 2018 safety manual. It warns workers that fly ash “may contain heavy metals such as arsenic and silica above the OSHA permissible exposure level” and that “all work areas that may contain fly ash will be tested by an industrial hygienist.”

The 2018 manual says workers “will be required to wear a respirator … and protective clothing when working in fly ash unless testing determines exposure to heavy metals is below OSHA (limits).”

USA TODAY Network-Tennessee contacted several contractors on TVA’s preferred subcontractor list, including G&A, but none returned calls.

Fly ash blowing in the wind

TVA’s newest coal ash landfill at Bull Run — the Dry Fly Ash Stack Lateral Expansion — is less than 150 yards from a children’s park and a sports field on Edgemoor Road in Anderson County. TVA is required under its landfill permit to keep fly ash from drifting into the air and being blown by the wind into the surrounding community.

USA TODAY NETWORK-Tennessee observed dust blowing from the landfill toward that park – the Kids Palace Playground – and sports field at least twice in one week in February. TVA says it’s up to contractors, workers and the public to alert the utility about fly ash worries. In the past three years, TVA hasn’t documented or investigated a single complaint, according to its own reports.

"Our environmental permit only includes fugitive emissions that cross our property line when related to stacking ash at the dry fly ash stack," TVA's Brooks responded. "None was reported and none crossed our property line."

TVA CEO's regulation claim contradicted

TVA CEO Johnson insisted in a January interview with WVLT-TV in Knoxville that disaster cleanup workers were kept safe thanks to a daily presence by regulators, including OSHA.

"Now, we spent a lot of time and a lot of money cleaning that up,” Johnson said. “Every day during the cleanup, the EPA the Tennessee Department of Environment and Conservation and OSHA were on the site. There are mountains of environmental data showing that there's no concern for public health."

The EPA and TDEC did not maintain a daily presence at the cleanup site after 2011. Even Jacobs’ chief safety manager stopped visiting the site daily by 2010, he said during trial testimony. OSHA never had a regular presence on the site. OSHA records show an inspector visited the site only once during the seven-year cleanup.

Brooks said Johnson wasn’t misleading and instead was engaging in hyperbole to emphasize his point that workers were kept safe.

“Mr. Johnson was affirming that these agencies had constant regulatory oversight of the project, regardless of their actual time onsite,” Brooks wrote. “Both TDEC and EPA had to ‘sign off,’ which they did, that the project was completed successfully.”

Jacobs is using a similar argument to defend statements its safety managers made to workers about coal ash. Jacobs Safety Managers Tom Bock and Sean Healy testified at the phase one trial they told workers they could safely eat a pound of coal ash daily but insisted they, too, were engaging in hyperbole.