Wind turbine noise: Temporary maximum limits draws complaints 

HOLLAND – A staunch critic of industrial wind projects told Holland residents this week who are worried about a big wind turbine coming to a local farm that they could see tougher sound standards in the future.

Annette Smith of Vermonters for a Clean Environment was hoping that the state utility regulators on the Public Service Board would heed concerns and complaints about noise and health impacts and lower the maximum level of sound allowed at homes near industrial-sized wind turbines.

But Smith said she was disappointed with the temporary sound standards announced by the PSB this week at the request of the Legislature, calling them worse than the original standards under which the Lowell and Sheffield wind projects were built.

The three-member PSB issued the temporary sound standards within the 45-day window required by the Legislature under Act 174.

The board kept the maximum level of sound allowed outside the exterior of a home at 45 decibels. The interior was also kept at 30 decibels in bedrooms, with measurements taken when bedroom windows are open in summer, partially open in spring and fall and closed in winter, from October to March.

The board reserved the right to have stricter limits on a case-by-case basis depending on topography and other factors.

Smith complained that setting the indoor maximum sound limit with windows closed does not reflect the reality in some homes, where people do open their windows in warm spells.

Holland residents said this week that the ambient level of sound outdoors is very quiet. A chart of noise levels shows that rural areas like Holland are significantly quieter, in the 20s decibels, than outside urban and suburban homes. While the human ear cannot notice a change of 3 decibels, a change of 15-20 is very noticeable, according to literature about sound and human hearing.

The sound standards have not and still do not address one of the persistent complaints about wind turbine impacts on health, that from the sound waves that create what critics call infrasound, a type of rumbling or hum that is too low to be heard but is experienced.

The PSB asked for and received comments and proposals from 40 different groups and individuals about the sound standards.

“The time constraints imposed by this deadline required the Board to move swiftly in developing the temporary rule …” the PSB members stated in their description of the interim standards.

“As a result, and out of necessity, we relied on the most stringent measures that the board has imposed on wind electric generation facilities to date, while at the same time retaining the discretion to impose more stringent standards on a case-by-case basis if a petition or application for a wind electric generation facility is filed before the board is able to develop and adopt a permanent rule governing sound emissions from these facilities.

“We realize that participants advocated for a variety of standards, both stricter and more lenient than the ones set forth in the temporary rule that we adopt today. Some commenters advocated for complex provisions that would have required a level of review not possible in the time allotted for the temporary rule.

“However, the standards we adopt today are temporary and will remain in effect only until the earlier of the effective date of a permanent rule, or July 1, 2017.”

“The PSB violated Act 174,” Smith said.

“The law says they can’t put in place anything that is worse than currently exists. The PSB just changed the interior standard to make it less protective.”

She pointed to the request by Renewable Energy Vermont, which asked to have the maximum indoor limit set with windows closed.

Smith said that at the end of the legislative session, Senate President Pro Tempore leader John Campbell, D-Windsor, said he hoped the PSB got the message about concerns about noise and siting.

“They did not,” Smith said.