AUGUSTA – When the Friends of Spruce Mountain saw their appeal to the Spruce Mountain Wind Project denied last week, the group’s lawyer also presented a proposed amendment to Maine’s noise rules in the state’s Site Location Law.
The result of a petition effort by the Maine-based Citizens’ Task Force on Wind Power, the amendment would have the Maine Department of Environmental Protection apply different standards to wind turbine noise than to other industrial noise.
They will have a public hearing before Maine’s Board of Environmental Protection, with experts on wind noise speaking on behalf of the Citizens’ Task Force. According to Cynthia Bertocci, executive analyst for the Maine BEP, the hearing date hasn’t been set yet.
Bertocci said there is a set noise limit for industrial noise that the Department of Environmental Protection uses for all projects, including wind power projects.
In rural areas like Spruce Mountain, where normal ambient sound is less than 45 decibels in the daytime, no development can be louder than 55 decibels in the daytime and 45 at night by the time the sound gets to nearby residences.
Wind-farm opponents say that’s too high for wind turbines because of a phenomenon called “wind shear,” a low-pitch thumping noise that often happens as wind turbines cut through layers of air moving at different speeds.
The new rules would limit nighttime noise levels to 35 decibels at nearby homes, and set the nearest turbine at least 1 mile from the nearest residence.
According to the Canadian Centre for Occupational Health and Safety, 40 decibels is the sound of a quiet room. A person talking about 3 feet away is about 60 decibels.
Citizens’ Task Force on Wind Power spokesman Brad Blake said the DEP and the Land Use Regulation Commission have cited state rules when not addressing concerns from groups opposed to wind power. “They’re just saying, ‘We can’t do anything because of the way the wind law was written,’” Blake said.
Rufus Brown, attorney for both the Spruce Mountain group and the Citizens’ Task Force, speaking about Maine wind projects, said at last week’s hearing that “Every single project has had adverse health effects.”
In a basis statement for the amendment, Brown writes that wind turbine noise is different from other commercial and industrial noise like trains and aircraft. The noise is of a lower frequency and is emitted “from high above the ground resulting in a pervasive and omnipresent character that dominates the soundscape.”
Brown argues that the repetitive, low-frequency sound has a high annoyance factor than can disrupt sleep and lead to higher stress.
Brown said wind projects can be built, but recent projects are being built too close to people.
According to Gordon Smith, a lawyer representing wind-farm developers Patriot Renewables, the closest residence to the proposed Spruce Mountain project is 2,200 feet from the nearest wind turbine. In Vinalhaven, where health problem complaints have been widespread, the nearest home is 1,200 feet from a wind turbine.
Patriot Renewables also is also seeking projects in Canton, Dixfield and Carthage. The Vinalhaven project was developed by Fox Islands Wind LLC. According to Smith, the noise modeling used when building the Vinalhaven project wasn’t as careful and conservative as the modeling Patriot Renewables uses.
Patriot Renewables uses a three-decibel buffer above their projected noise limits to account for modeling errors.
A June 2009 study by Maine Public Health Director Dora Mills disputed the idea of health effects resulting from turbine noise. She wrote that she found “no evidence in peer-reviewed medical and public health literature of adverse health effects from the kind of noise and vibrations heard by wind turbines, other than occasional reports of annoyances.”
Mills also found that low-frequency noise is only harmful at much higher sound levels than wind turbines produce.
When the Board of Environmental Protection hears testimony on the proposed changes, they can decide whether to adopt the amendment, reject it or to make changes to it before adopting it. Bertocci said the hearing will probably be set for a future BEP meeting date.