Town Administrator Robert Mercier and Burlington Department of Public Works Superintendent John Sanchez updated Town Meeting members on the during Town Meeting last night.
As reported yesterday on Burlington Patch, the town is currently under to boil water after a routine test of the town's water supply came back potentially positive for trace amounts of the E. coli bacteria.
Mercier said the town first became aware of a possible issue last Friday when a routine test showed the water may have been contaminated. Town officials connected with the DEP for additional tests and verification of a problem. Mercier said in the past positive test results have normally been the result of human error in collecting or transporting samples or in the laboratory.
At first, Mercier said, it appeared this may be the case in this instance. Samples taken upstream and downstream from the test location that came back positive showed no sign of the bacteria.
"It was hard for us to figure out how it could be that a site in the middle could be contaminated," he said.
Mercier also said that the water had been properly treated.
"One of the sites where we pulled potential E. coli is more than efficiently chlorinated so it shouldn’t be able to survive," he said.
However, the town conducted additional tests over the weekend, in conjunction with the DEP, and received additional verification that there was a potential issue with the water supply. Yesterday, the DEP advised the town to put out a recommendation that residents take the precaution of boiling all water before consumption.
Mercier said additional tests will be conducted today and tomorrow. In order to declare the situation over, he said, the town will need to conduct two full rounds of testing that come back negative of E. coli.
Sanchez said the town has been attempting to locate the source of the contamination, but said that because the upstream and downstream tests came back negative it is difficult to trace source. He did say that the tests of the town's water tanks and water facilities have come back negative.
As a precaution, all the sinks and water fountains in the town's schools have been blocked off with plastic and the town will be providing bottled water to the schools for student use. Most of the schools' water supplies were tested Monday and all tests came back negative.