NORWICH — After three years of evaluating the danger of the chemical contamination in the Moore Lane Bridge, the Selectboard decided last week to continue efforts at containment, a move some residents are calling just another half measure.

The board voted unanimously last Wednesday to install a waterproof membrane under the pavement on the bridge deck. The goal is keep water from mixing with the petroleum-based asphalt emulsion the bridge was treated with around the time of a 1989 reconstruction project. When wet, the emulsion mobilizes and pollutes the water below in Bloody Brook, where an oily sheen is sometimes visible.

The 50-foot span is located on Moore Lane, which connects Beaver Meadow Road and Turnpike Road near Huntley Meadows.

“I think this option is a good compromise,” board member Matt Swett said at the meeting.

The possibilities the board considered ranged from maintaining the current containment system to completely replacing the bridge.

The membrane, either a synthetic plastic or rubber material, is among the less expensive of seven options proposed by Stantec, an international engineering company with offices in Vermont and New Hampshire.

The estimated up-front cost of the membrane is $125,000, and there would be an annual $5,000 monitoring cost.

Although the board voted unanimously for the membrane option, board member Marcia Calloway expressed reluctance.

“We’ve known it was a problem and it’s not going to go away,” she said.

Calloway favored removing the contaminated timber and building a new concrete bridge deck, which is estimated to have a one-time cost of $745,000.

Because the bridge is in good condition besides the contamination, it is unlikely the state would allocate funds to Norwich to help pay for replacing the bridge, the report said.

Peter Orner, who lives next to the woods, agreed with Calloway.

“We have kicked this can down the road a number of times already,” said Orner, who joined the meeting via Zoom from the streets of Santiago, Chile. “I love this bridge. It’s a cute, beautiful bridge, but it’s full of toxic and cancer-causing chemicals.”

Orner first alerted town officials in 2019 about a chemical smell and discharge seeping into the brook where his children learned to swim, the Valley News has previously reported.

In 2021, the state Spill Program, which assesses the environmental impact of hazardous materials spills, issued a directive to Norwich to prevent the leakage and recommended an analysis to identify the contaminants involved.

In June 2022, an environmental consultant hired by the town collected water and sediment samples and tested the emulsion. The testing found the emulsion contained levels of naphthalene, fluoranthene, and benzo(a)pyrene exceeding residential standards. The chemicals can cause negative health effects and, in some cases, cancer.

Also in 2022, the town spent $62,000 to install “a more robust containment system,” consisting of two layers of absorbent fabric and plywood sheathing across the bottom of the bridge deck.

But in 2023, the town once again observed breakthrough emulsion dripping down the bridge.

Last summer, the town spent $12,000 for a Massachusetts-based environmental and industrial services company to install a trough made out of timber containing an oil-absorbent medium along the bridge abutments to catch the contaminants as they drip down, according to Selectboard meeting minutes.

However, a report from Stantec late last year found it is not clear if the trough is stopping all of the emulsion from reaching the brook or not.

Between the reports and work done on the bridge, the town has spent about $120,000 since 2022, Town Manager Brennan Duffy said in an email to the Valley News.

After the board’s recent vote, Orner said he “respectfully dissents” and predicted he will be back before the board in a few years when chemicals are leaking into the brook once again.

“This is throwing money into yet another temporary solution,” he said.

Emma Roth-Wells can be reached at erothwells@vnews.com or 603-727-3242.