GARDINER — Councilors on Wednesday will weigh whether to choose a new heating source for the wastewater treatment plant other than natural gas, potentially jeopardizing the chance for a pipeline to be expanded to others in the South Gardiner area.

A representative from Summit Natural Gas of Maine, the company building out its gas pipeline system in Gardiner, told councilors at their meeting two weeks ago that he couldn’t guarantee the company will expand to South Gardiner with or without the wastewater plant as a customer.

Michael Duguay, director of business development at the company, said the plant’s heating use is equivalent to that of only about eight homes, but he didn’t know whether a decision to expand in the area would hinge on that amount.

“Truthfully, as I mentioned, it makes it harder because any load you lose, you then have to make that up with some expansion somewhere else in the system,” he told the councilors on Aug. 21.

City Manager Scott Morelli, who recommended natural gas to the council, said the councilors might delay making a decision until they know more about Summit’s plans.

Besides the discussion on a new heating source for the wastewater treatment plant, the council will consider appointing Zachary Hanley to the Planning Board, consider terminating the tax-increment financing district for the now-closed Associated Grocers and discuss whether to pursue funding from the Kennebec Valley Council of Governments for a streetscape study of Brunswick Avenue.

The top two contenders to replace No. 2 heating oil at the wastewater treatment plant and the $21,000 a year it costs to heat the building are natural gas and an effluent thermal heating system.

A consultant that performed a heating study for the city, Woodard & Curran, recommended converting to natural gas from heating oil; but the Wastewater Advisory Board recommended the effluent thermal option.

Converting to natural gas would cost $98,000 and would save $14,000 per year.

Effluent thermal would entail around $150,000 in conversion costs but save about $2,000 more a year than using natural gas would. It also has the advantage of being renewable because it would use the outflowing of water to power the plant.

Wood pellets, a third choice, would cost $10,000 a year, with a $113,000 conversion cost.

Morelli said the city wouldn’t tell people to switch to natural gas, but it’s important to give people the option to convert.

He said that’s why the city needs to consider whether its decision about the heating source for the wastewater plant will have ramifications for residents in the area.

“It’s a little bit of a poker match,” Morelli said.

Paul Koenig — 621-5663

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