After half-million gallon spill into northern VT river, ‘radio silence’ from lab
by Logan Solomon, Community News Service
NORTH TROY — Alarmingly high levels of E.coli were found in an early February sample from a small town wastewater facility outflow into the Missisquoi River, but local officials say the testing lab didn’t tell them until weeks later — meaning the bacteria could have continued to leave the plant for most of the month.
And it isn’t the first time that’s happened in recent years.
“I usually get a phone call (when results are high),” said Karson McMahon, chief operator of the North Troy Wastewater Treatment Facility. “Unfortunately, they did not call me. I thought everything was okay. I didn’t see anything until they sent me the (full) results.”
By that point at least 500,000 gallons of discharge had gone into the river.
Each month, multiple routine wastewater samples from North Troy are sent to Endyne Labs, a chemical and microbiological laboratory, to test for indicators of the plant’s impact on water quality. Typically, McMahon said, operators receive a call from the laboratory as soon as it detects a pollutant above a certain threshold so that the situation can be remedied as quickly as possible.
In this instance, McMahon said he received radio silence, finding out about the problem in paperwork, weeks later.
The problem was certainly worth communicating. E.coli concentrations from the Feb. 8 sample were so high that you would find 8,500 probable colonies in a sample the volume of a standard Coca-Cola can.
This is concerning, given that the facility discharges into the Missisquoi River, a recreation spot where many fish and swim.
Why were the results delayed? It’s hard to say — Endyne representatives declined to make themselves available for an interview after repeated requests.
Once McMahon was made aware of the high test results, he said, he conducted a resampling Feb. 27 that showed no E.coli. He then filed a public notice on March 2 — meaning the first time members of the community would have been alerted to the potential problem was almost a month after the water sample was taken.
McMahon does not think the original results are accurate, noting the water’s clean appearance and a history of the lab sending results that appeared questionable.
In January 2022, according to state records, McMahon filed a public notice about a routine water sample that the lab said contained a high amount of E.coli, an amount roughly half the level of the February sample a year later. But, he noted in the report, the tank used to disinfect the wastewater had been cleaned just two days beforehand.
“Inspection of the disinfection system and all other components showed no reason for high E.coli,” McMahon wrote in the report.
However, McMahon understands that he is not in the position to make that sort of judgment.
“We can’t prove it. We’re not laboratory techs, but we kind of feel like it was possibly a mistake in the lab,” he said. “But again, we can’t really argue that.”
This also isn’t the first time McMahon has described delayed test results from Endyne concerning E.coli in the plant’s discharge.
In May 2021, state records show, McMahon wrote that his team wasn’t notified by the lab for more than a week about a sample that tested high for E.coli concentrations, although at significantly less levels than the other results mentioned. Over a span of almost two weeks before the issue was resolved, he wrote, about 410,000 gallons of discharge went into the river.
Endyne Labs’ website says the company has laboratories in Vermont, New York and New Hampshire capable of performing any necessary testing for municipal wastewater operators.
McMahon’s claim raises questions about the accuracy of wastewater discharge test results elsewhere in the state. For many years Endyne Labs has provided water testing services to dozens of municipalities across Vermont. If tests are inaccurate — or results are delayed — plant operators across the state may be misguided in the steps they take, posing risks to the environment and people’s health.
In North Troy, the delayed notification meant McMahon did not take an earlier resampling. So he does not know when exactly E.coli stopped discharging from the plant. But he said it certainly stopped flowing from the plant at some point before that resampling.
“Do I think that E.coli was coming out (of the plant) the whole time?” he asked himself. “Absolutely not.”
But E.coli was leaving the plant for a while. The public notice says 500,000 to 1 million gallons left the plant. The gallon-to-gallon levels are unknown. All that can be said is that E.coli concentrations were very high Feb. 8 and non-existent Feb. 27.