Discussion continues on adoption of the “nanosystem” for Hinesburg’s water supply, Trefry thanks Rocky Martin for help during a staff emergency

by Margery Sharp

Prior to the Hinesburg Selectboard’s Feb. 9 meeting, Chair Jon Trefry thanked Rocky Martin and gave him a gift for his willingness to help the water department continue making repairs and well testing when a department employee was injured and a second one resigned.

Nanofiltration

Water Source Engineer Joe Duncan of Aldrich and Elliott of Essex described his and his staff’s recommendation to construct a nanofiltration system for the two planned town wells to be located south of Shelburne Falls Road. In November, residents approved 1.5 million for the project.

Selectboard member Tom Ayer noted that “Projects have been delayed…the State of Vermont had said no more hookups until there’s water.”

Duncan told the Selectboard “We need 100 percent direction before we start,” adding even if all aspects of the water supply project are in place, including the permits and approved treatment system, “it would be two to three months before we can start.”

The nanofiltration system is a low pressure reverse osmosis action incorporating a 20-foot membrane which filters the water before it is sent out. When asked, Duncan said the membrane should be cleaned with a citric acid every three or four months and replaced “every six to seven years,” and that it takes “less than two days [to clean the membrane] and there is a bypass system used while this is in progress.”

Industrial Services Inc., coincidently is located in nearby St. George, is supplying the equipment for this nanosystem process. “The proximity of the company to Hinesburg and its pricing plus its expertise are very good for the project,” Duncan added.

Why treatment?

An audience member said, “Hard water has never been a health detriment,” adding often a substance said to be benign later turns out to not be. Someone else asked about the possibility of using a stripper, a system that blows air through the water stripping out the caustic chemicals. Trefry responded that the building design includes this system. When question, Trefry also disclosed that there is no aluminum in the water.

The treatment building will be 60 x 30 feet and can accommodate two membrane units. When needed, the system could handle 500 gallons per minute. The roof will have a north/south exposure with natural lighting. Heated by gas, there will be humidity control. Efficiency Vermont will most likely look over the set up.

Town survey

“I believe a (town wide) survey about the water treatment is necessary,” said Selectman Andrea Morgante, “we promised it.” Selectman Phil Pouech agreed saying, “We need feedback.” Selectmen Mike Bissonette and Tom Ayer disagreed for a survey, Ayer saying “I am happy to go forward.”