Chief Engineer Fred McNeill
Fred McNeill, chief engineer at the Manchester wastewater treatment plant, seen here giving a tour in April 2021, says he is annoyed that Ohio research company Battelle didn’t release the complete results of its research on emissions at the plant.

Manchester wastewater treatment plant stack

The air emissions pipe from the Manchester wastewater treatment plant, as seen from Gay Street.

 

Scientific researchers have recorded the destruction of some PFAS chemicals in a Manchester incinerator but also detected an unexplained amount of toxic fluoride emissions, according to research findings obtained by the New Hampshire Union Leader.

The Ohio research firm Battelle also found that while half the PFAS — the so-called forever chemicals — were destroyed in the Manchester wastewater treatment plant incinerator, others were created. The most common were GenX chemicals, the shorter-chain chemicals manufacturers have turned to as a substitute for PFAS.

Battelle, which is marketing its own treatment system, reported a synopsis of the findings to the state Department of Environmental Services and officials at the wastewater treatment plant in May.

Officials familiar with the findings say they need more data to draw conclusions. One public health advocate said the unexplained fluoride emissions show that experts have yet to get a handle on the forever chemical.

“It’s clear to me, if you’re having greater output than input, something is wrong,” said Mindi Messmer, a former state representative and co-founder of the advocacy group New Hampshire Science and Public Health.

She also noted that Battelle measured for only 30 PFAS compounds. The U.S. Environmental Protection Agency recognizes more than 12,000.

In 2019, Battelle started analyzing the fate of PFAS at the Manchester wastewater treatment plant, the only wastewater plant in the state that incinerates sludge. Emissions from the incinerator exit through a 116-foot high exhaust pipe at the plant, which is located on the banks of the Merrimack River in south Manchester.

The incinerator destroyed 51% of the mass of PFAS chemicals contained in the sludge that it incinerated, according to research findings.

But in the biggest quandary, the amount of fluoride released into the air — about 16 kilograms a day — is 44,000 times the amount that scientists could explain. Battelle describes fluoride-related compounds as toxic.

Accounting for chemicals

The term PFAS represents a family of complex chemicals used in Teflon, firefighting foam, spill-resistant fabric and other modern-day products. Characterized by a strong chemical bond of carbon and fluorine, PFAS chemicals are described as forever chemicals because of their ability to remain intact in the outside environment.

They have shown up in drinking water wells in New Hampshire, especially in Merrimack, where Saint-Gobain Performance Plastics has been blamed for PFAS contamination and officials have detected high levels of kidney cancer in residents.

The EPA regulates neither fluoride nor PFAS emissions at the Manchester plant. The plant has been voluntarily monitoring some PFAS compounds since 2019.

A state Department of Environmental Services official involved with PFAS cautioned against drawing any conclusions from the 16-page synopsis.

“It’s hard to be black and white. They don’t have a lot of data behind it,” said Cathy Beahm, administrator at the DES Air Resources Division. Beahm is a liaison for PFAS issues.

Beahm said the biggest takeaway from the findings is that 99% of PFAS coming into the plant in the wastewater stream leave in the water that is cleaned and discharged into the Merrimack River.

The biggest focus of the Battelle study was what happens to the PFAS in the sludge that is burned in the incinerator. She can’t explain the fluoride.

“In a perfect world, that would all add up. We’re not in a perfect world,” she said.

The plant’s chief engineer and operator, Fred McNeill, believes fluoridation of Manchester drinking water, which has been going on since the early 2000s, is responsible for the unexplained releases of fluoride.

“Emissions are so heavily regulated, that if there was something to worry about (with fluoride), (the EPA) would regulate it,” McNeill said.

But Messmer said she’s not so sure about that. She agreed with a suggestion that the EPA may be hesitant to regulate fluoride as a pollutant because public health officials hail its benefit to dental health.

A new approach

Meanwhile, two weeks ago Battelle announced it has developed a “PFAS Annihilator” that destroys the chemicals and prevents their entry into drinking water.

The Annihilator uses “super critical water oxidation” to break the carbon-fluorine bond, it said in a release.

The Columbus-based firm said it has invested millions in the scalable technology, which is now being used to destroy landfill leachate in a Michigan facility.

In an email, Battelle chemical engineer Steve Rosansky said the process subjects the fluid to high temperature and high pressure (705 degrees Fahrenheit and 3,200 pounds per square inch). The process produces carbon dioxide, water and hydrofluoric acid, which is neutralized to form innocuous salts.

Battelle has measured destruction of up to 99.99% of PFAS in the three waste streams it addressed — industrial wastewater, landfill leachate and firefighting foam, Rosansky said. There are no regulatory barriers to the process, he said.

Battelle has called the Manchester research the first of its kind.

Plant engineer McNeill said Battelle did not undertake any experiments at the Manchester plant and only took measurements for research purposes. But he is irked that Battelle has not released the “mass balance” — the complete data that shows all PFAS chemicals entering and all PFAS and other substances exiting the plant.

“We have not gotten the stack test, which is the meat and potatoes of the study,” McNeill said.

Beahm said the DES asked Battelle for the data in May. She has received no reply, but the data use agreement specifies that Battelle will first use the data for a peer-reviewed study, she said.

She had no estimate for how long that will take.

Battelle said its Annihilator is destroying all PFAS, but Messmer is skeptical. Saint Gobain said the same thing with its new incinerator, but 19 PFAS chemicals have been detected there, she said.

She said the solution is to reduce the use of the chemicals.