Antrim Wind noise and light complaints not yet settled

Recent recommendations from a subcommittee of New Hampshire’s Site Evaluation Committee (SEC) disappointed some neighbors to the Antrim Wind turbine project who wanted more precise sound measuring standards than what the committee appears poised to adopt, but the conversation is far from over.

Nearby residents have lodged multiple noise and lighting-related complaints since the nine turbines went online in December 2019. Earlier this year, the SEC embarked on an overhaul of their complaint handling process after complainants said they felt ignored. Any time the SEC receives a noise complaint about the turbines, they’re tasked with conducting a sound study in conditions similar to those on the date and time of the complaint – all that’s being determined right now is the method of measurement, outside counsel to the SEC Michael Iacopino said.

Since March, the discussion has narrowed in on determining an acceptable time period over which to measure noise levels, as complainants took issue with Antrim Wind parent company TransAlta’s practice of averaging noise levels over an hourlong period, a method which they believed obscured shorter periods of louder sounds. Turbine neighbors like Antrim resident Richard Block were instead pushing for eighth-of-a-second intervals for measuring noise compliance, a standard that TransAlta lawyer Barry Needleman decried as “impossible for any wind project to meet,” according to a summary of his public comments provided by TransAlta.

At a hearing on July 21, the SEC subcommittee agreed not to recommend using eighth-of-a-second intervals, but they also didn’t believe they had to stick with hourlong averages. They recommended the SEC require at least a five-minute measuring period, with the exact length to be determined by the professional conducting the evaluation.

Although the recommendation is “very upsetting to the turbine neighbors,” Block said, he and fellow activists have already fired back in advance of the committee’s next hearing, laying the case for a different interpretation of the SEC’s existing rules. Although the subcommittee made recommendations in mid-July, the SEC is yet to formally adopt sound measuring standards.

Regardless of measurement standard, a noise violation would not necessarily require all the turbines to shut down, Iacopino said. Noise issues under certain conditions could be addressed by a number of different mitigation methods, he said, including stopping the blades for a certain period of time, running every other turbine, or rotating the blades to face in a different direction.

Meanwhile, more investigation into the blinking lights atop the turbines is forthcoming after Block filed an analysis of TransAlta’s own data on July 20, which indicated that the lights have been blinking between 30 and 50 percent of the time at night even after recent upgrades were completed.  That’s a lot more time spent “on” than than what was originally proposed, Block said. Both the SEC and TransAlta expect to discuss the analysis in an upcoming public meeting, representatives said. “In the meantime, we are continuing to work with the ADLS provider, Terma North America, to minimize the visual  impact of lighting on neighboring areas while remaining in compliance with federal regulations designed to ensure aviation safety,” a representative for TransAlta said.

“TransAlta built the Antrim facility to meet compliance standards and that has always been the goal and remains so going forward. We are pleased that the SEC subcommittee’s recommendation recognized that Trans Alta conducted its post-construction studies properly and in accordance with SEC rules. TransAlta is confident that Antrim Wind is and will remain in compliance with the sound limits adopted by the SEC,” a representative for TransAlta said.