Ammonia leak interrupts weekend activity at Ben & Jerry’s factory
August 28, 2023 | By Lisa Scagliotti UPDATE: This post was updated with comments from Ben & Jerry’s on Aug. 29.
An ammonia leak in a refrigeration system inside the Ben & Jerry’s Waterbury ice cream factory on Friday temporarily halted production, sent employees home, and shut out the public for part of the weekend.
The Ben & Jerry’s ice cream factory on Vermont Route 100 is one of the state’s busiest visitor destinations. Photo by Lisa Scagliotti
From 1 p.m. Friday until 10 a.m. Sunday, the plant’s visitor areas – its scoop shop, gift shop and tours – were closed, according to the company’s websites. Production was also suspended from Friday afternoon through Saturday at least.
Reached Monday, the chief of the state’s Hazardous Materials Response Team in the Vermont Department of Public Safety said an ammonia leak occurred at the ice cream plant. The leak was minor and below a level that requires reporting to the federal Environmental Protection Agency, said Patrick McLaughlin, noting that Ben & Jerry’s staff gave the state “a courtesy notification” of the incident.
A leak of 100 pounds or more of anhydrous ammonia requires reporting, McLaughlin said. “This was 10 times under that amount. It was mitigated quite quickly. There was no big hazard.”
No one was injured and the plant closed as a precaution. The company over the weekend, however, didn’t offer any public explanation for the temporary factory closure beyond website and Facebook posts saying the it was due to “unforeseen circumstances.”
Company spokesman Sean Greenwood was out of town for the weekend and responded to inquiries from Waterbury Roundabout on Monday.
“My understanding is they needed to perform some maintenance on the machinery, and out of an abundance of caution – decided it would be easiest to do without extra people on site,” Greenwood said in an email. “No one was in danger … tours and the Scoop Shop were reopened yesterday for business as usual.”
A Friday Facebook post announced the unexpected factory closure. Click to enlarge. Screenshot
It’s unclear when production resumed. The factory is the company’s smaller of two production facilities in Vermont – the other is in St. Albans – and it typically is in operation around the clock.
On Tuesday, Greenwood offered more detail, confirming there was “a minor leak of one pound of ammonia that vaporized” and that it was reported to the state as a courtesy since it fell below a level requiring a report. “No guests or employees were in danger. Out of an abundance of caution, it was decided to keep our fan and employee safety as the priority while the repair was completed over the two days,” he said.
The leak involved anhydrous ammonia which is used as a refrigerant and is key to the plant’s operation. “You can’t make ice cream without cold pipes,” McLaughlin said.
The National Institute for Occupational Safety and Health calls it “a pungent, colorless and toxic gas or liquid that, when concentrated, is corrosive to human tissue upon contact.”
The ammonia is normally stored in a closed-loop system, McLaughlin said. When contained, the liquefied gas is under pressure and when the pressure is released, the liquid evaporates rapidly, forming an invisible vapor or gas. Because its gas form is heavier than air, it has the potential to come in contact with humans, the Centers for Disease Control and Prevention explains.
Exposure could cause irritation, swelling and burns to eyes and skin. Inhaling anhydrous ammonia gas can cause breathing problems, wheezing or chest pain and contact with its liquid form can result in a frostbite-like injury, according to NIOSH.
On Friday, plant operators were servicing a line break that resulted in the “minimal release” of ammonia, McLaughlin said noting that there was no “respiratory event” for the company to report. “We weren’t even close to having to respond,” he said.
Plant managers “ended up shutting down out of an abundance of caution,” McLaughlin said, adding that the affected equipment then needed repairs, which led to a wait for a part and a technician.
Greenwood acknowledged that the interruption in the factory meant less production for the weekend but that the plant will make up for it. “The 100 total team members will catch back up on the volume projected over the next two weeks as that downtime means we didn’t make a few hundred thousand pints a day that we could have – but you can’t put a price on keeping everyone safe and doing the right thing,” Greenwood said.
McLaughlin said that state hazardous materials staff several weeks ago paid a “walk-through” visit to the plant to reconnect with Ben & Jerry’s representatives in person after contact for the past several years was limited due to the pandemic. He said the plant’s staff is highly trained and has equipment and protocols in place to handle emergencies connected with the materials used and stored at the ice cream manufacturing facility.
“We work with them on drills. We have a good working relationship with Ben & Jerry’s,” he said.
Ben & Jerry’s is one of Waterbury’s and Vermont’s largest employers with approximately 1,000 workers statewide. Its Waterbury ice cream plant is also one of the state’s most popular tourist attractions.