Here’s a bit of news that might be spun either way, depending on your predilection.  Jane Davis, who was driven from her home by wind farm noise, has been compiling information on English wind farms and noise complaints; she has found that 37 wind farms have spurred some sort of noise complaints nationwide.  This amounts to about 1 in 7 UK wind farms, in contrast to an oft-repeated mantra that “only four” UK wind farms had noise issues, and they’d been “resolved.”  The new numbers could support those cautioning that wind farm noise issues are more widespread than generally acknowledged, AND those who claim that noise issues are the exception rather than the rule; it certainly reinforces AEI’s theme that we need to acknowledge that a minority of people are affected by noise around wind farms, and that we must come to grips with how to address this.

This article in the Telegraph details some of the information shared at a gathering of wind farm noise campaigners, WindCon2010.  Gillian Haythornthwaite, who lives near the wind farm in Askam with her partner Barry Moon, said it has been a “devastating” experience. ”It is a dreadfully irritating whoosh, whoosh noise,” she said. “It is unbearable to be outside in the garden when there is the noise.”

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Electrical engineer Siva Sivoththaman has been named to the newly-created Ontario provincial Research Chair in Renewable Energy Technologies and Health.  Local activist groups that have raised concerns about the effects of wind farm noise on neighbors had hoped that this position, created as part of Ontario’s new Green Energy Act, would take the lead in formally investigating the negative health effects some neighbors of wind farms have reported.  However, the choice appears to be more oriented toward the technology aspect of the Chair’s responsibilities.  As noted in the request for proposals: “The Chair in Renewable Energy Technologies and Health will focus first on emerging science and technology related to wind turbines, and then will explore the potential health effects from renewable energy.”

According to a news release, “Dr. Sivoththaman will bring focus to multi-disciplinary activities in renewable energy technologies and health, ensuring that health and safety are top priorities in the induction of new technologies. His research program will develop new technical approaches and will provide guidelines in setting standards to ensure health and safety in the manufacturing, use, and end-of-life phases of renewable energy technologies.” Sivoththaman’s research centres on silicon-based crystalline and thin-film photovoltaic devices, and he serves as director of the Centre for Photovoltaic Systems and Devices, which occupies much of the photovoltaic research building beside Matthews Hall. His interest extends to nanocrystalline semiconductors, and he was the first director of the University of Waterloo’s nanotechnology engineering program when it was launched in 2004.

Two leading Ontario wind activist groups expressed their disappointment with the choice; Wind Concerns Ontario said “We have no faith in any meaningful body of evidence being produced on health effects from wind turbines by this government-funded non expert and Ontarians will suffer for it,” while the Society for Wind Vigilance chair Dr. Robert McMurtry said the choice missed the mark in that “the lead and expertise of this Research Chair would more appropriately have been a clinician scientist. We strongly encourage the new Chair to seek the appropriate collaborators as the research program is established.”

It is as yet unclear what the Chair’s timeline will be in addressing the dual (and quite distinct) topics he is charged with overseeing.  Given the widespread concern about health effects, and the role this concern is playing in the wind development process in Ontario and elsewhere, we hope that the two topics will be pursued simultaneously.  And indeed, as McMurtry suggests, it is clear that the Chair will need to bring in some experts in health and acoustics to effectively address the health aspects; in the spirit of collaboration and inclusiveness, we can also hope that his research/investigative team draws from qualified experts who have expressed concerns about wind noise, as well as those who have previously worked on reports that found few health effects.

The Fox Islands Electrical Cooperative on Vinalhaven, an island off the coast of Maine, has begun a month-long experiment as a first step in trying to come up with a local solution to noise issues from three wind turbines that began operating in November.  About two dozen people within a half-mile of the turbines have reported annoying levels of noise, with six property owners claiming that their lives are severely impacted.  Others in the same area who can hear the turbines are not particularly bothered by the noise.

Shortly after the turbines started operating, and some residents (including some who were excited about the wind farm, and some who had been skeptical) reported unexpected noise issues, neighbors began noting the times that the sound was most troublesome, in an effort to identify what wind directions or atmospheric conditions might be most to blame.  At its January meeting the Board of the electric coop decided to conduct a month-long “experiment” during February, in which the turbines would be slowed down in random patterns.  Sound measurements will be made throughout the month, and the 38 households within a half-mile are being asked to log their sense of the noise on a regular basis (half these households are summer people, so are unlikely to be participating). In a letter to coop members, the board said the experiment “will enable us, as a community, to figure out what to do and come to a solution that works, as well as possible, for everyone.”

A very detailed article in The Working Waterfront, a local paper, features a variety of comments from a locals about the process that is underway to find a community-based solution to the noise problems. Some find that the noise is moderate enough to be tolerable, easily drowned out by other sounds such as the TV or a car passing by, or being no more bothersome than a dishwasher running in another room; one person remembers the noisy generator that used to provide power to the town in the 60s and 70s, which people got used to.  Some who have been disturbed share their perceptions, as well;  Ethan Hall notes that “I’ve never heard anything in my life that sounds like it.”  Both he and Lindgren (another neighbor being affected) believe that current sound measurement standards do not take into account the complexity of turbine noise and its true impact. “The nature of the sound is so unique, that to try and quantify or qualify it with a strict dBa [decibel] measurement is an entirely inadequate way of describing the effect on people and surroundings,” Hall feels.  An hour-long radio interview with Hall and others being affected, recorded this past December, is available on the WERU website.

The latest in AEI’s ongoing series of comprehensive special reports on key topics is finally done!

This one is modeled on AEI’s acclaimed annual reviews of science and policy developments in ocean noise, but focuses for the first time on wind farm noise issues.  The 30-page report covers new research, public concerns, and industry trends over the past year.

Read the report in the embedded pdf reader below, or download a pdf copy.  Click on to below the fold for a table of contents and the report’s brief Introduction.

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A hearing by the Minnesota Public Utilities Commission heard testimony from residents and agency staff this week, and indicated that it was going to take its time in setting statewide wind farm siting guidelines.  ”I think there are a lot of remaining unanswered questions. I think there are a lot of … substantive questions as well,” Commissioner Phyllis Reha said. “I think the commission has a lot of work to do before we make any kinds of decisions.”

Monday’s hearing focused on a report issued last year by the Minnesota Department of Health outlining the potential health impacts from wind turbine noise. The PUC and its staff requested health department officials review scientific literature after people statewide raised concerns regarding wind projects.

In the scientific report, state health officials - drawing from National Research Council findings - noted that noise from wind turbines “generally is not a major concern for humans beyond a half-mile or so.”  Nonetheless, the report and PUC staff recommended that setbacks be increased only to 1000 feet; current regulations set a 500 foot minimum, but the night time noise limit of 50dB means that in practice, most turbines are sited at least 700-1200 feet from homes.

Some groups - including Goodhue County residents - have advocated setbacks of six-tenths of a mile or even 1.25 miles to prevent possible health effects, a point PUC staff and others say is supported by “scant” evidence. Still, Commissioner J. Dennis O’Brien said, “We know these issues are strong and heartfelt … and genuine and real. We’ll just have to struggle with it for a while, I think.”

Very cool collection of various approaches to sound mapping, recently posted at Weird Vibrations.  Here’s the first post, sharing their overview of several sound mapping models, including collaborative documentary, composition, preservation, and policy-oriented.  And here’s a follow-up post of others sent in by readers.  And to go one step further, here’s a delicious link from a commenter, to his own collection of sound maps.  And, oh, what the heck: here’s the current list of sound maps from AEI’s main site!

Paris Sound Map (click to read 1st post)

Those of you who were attracted to this particular post topic may well also enjoy checking by Weird Vibrations this week, where they’ve just begun an “open thread” on Acoustic Ecology, centered around their upcoming reviews of Gordon Hempton’s One Square Inch book, and a book on sound weapons; the initial questions posed are promisingly provocative: “ First, is understanding sound as an ecosystem practical? In other words, can this formulation help us deal with noise in a just fashion? How does the ecological metaphor sit with you? Second, does acoustic ecology’s focus on “natural” preservation make it essentially conservative? This is a charge that’s latent (if not explicit) in some recent Sound Studies work that foregrounds technology. What do you think?”

Two different acoustic studies near the Willow Creek Energy Center in eastern Oregon have found that the state’s wind farm noise ordinance is being violated at several homes nearby.  How often and by how much the violations are occurring remains under contention. As reported by the East Oregonian, the commission heard from several acousticians as well as the neighbors themselves.

The state allows wind farms to be up to 36dB at neighboring homes (10dB over the night-time ambient of 26dB–based on the assumption that excess noise will not be bothersome until it exceeds ambient by 10dB).  After several neighbors raised concerns about noise, Invenergy, the wind farm developer, hired acoustical consultant Michael Theriault to take measurements.  He found that noise levels at three homes were “usually less than 37db” and that at one home, “the noise ‘moderately’ exceeded the noise code about ten percent of the time.” (it is unclear what “usually” means in this report, or what averaging period was used in the determination)

However, the Theriault did no recordings when wind speeds exceeded 9m/s, because the company says their turbines don’t get louder after that point.  This may well be true, but sound propagation can vary widely with atmospheric conditions, especially when wind is higher aloft (at turbine hub height) than on the ground.  Acoustical consultants hired by the four landowners presented findings that included measurements when wind speeds were higher, which showed that the noise at the Eaton’s residence hovered just above the noise standard on a regular basis, and at the Williams residence it regularly went above 40 decibels. The wind farm consistently broke the noise rule at precisely the time when Theriault decided not to use the data - when wind speeds exceeded 9 meters per second. When the data is analyzed in a wider range of wind speeds,  the wind farm was in violation of the rule 22 out of 37 nights. ”I’m not sure how someone can say this is an unusual, infrequent event,” said Kerrie Standlee. “To me, 59 percent is not occasional or unusual.” Standlee’s noise study also went beyond Theriault’s in that he gave the residents a sheet of paper to log their experiences with time and date. He then overlaid those comments on the data and showed that when the residents reported high noise, the wind was blowing from a particular direction or at a particular speed.

The commission also heard heartfelt testimony from the residents themselves, who said that their lives had been completely changed since the wind farm came. ”A basic right in my life is to live in my beautiful home with my peace and quiet, and now I can’t do that,” Dan Williams said. When the testimony ended, the planning commission agreed to wait until their next meeting to make a decision about whether - and how - the Willow Creek wind farm must mitigate the noise problem.  An earlier article focusing on the experiences of people near the wind farm is available here.

In the best overview I’ve yet seen of efforts to solve the “problem” of electric cars being so quiet, the New York Times Wheels blog provides a tour of the the apparently burgeoning of field sound design for these future (and increasingly, present-day) vehicles.  Most designs plan to incorporate sounds that will alert nearby pedestrians of a car nearby, but will only emit sound when the car is slow-moving (above 12 or 15 mph, tire noise will be sufficient).

A speaker embedded in the bumper of a Fisker Karma (click to read NY Times blog post)

Among the key questions is whether electric car owners will be able to customize their car’s “voice,” ala cell phone ring tones, or if they should be standardized.  So far, individual auto companies are each pursuing their own standard sounds, which could presumably become part of the “look and feel” of the car’s branding.  A Nissan engineer quoted in a September article from Bloomberg,  says that “we decided that if we’re going to do this, if we have to make sound, then we’re going to make it beautiful and futuristic.” The company decided on a high- pitched sound reminiscent of the flying cars in “Blade Runner,” the 1982 Ridley Scott film. “We wanted something a bit different, something closer to the world of art,” said the Nissan designer.  At least one acoustic design company has turned its attention to becoming the “go to” company for automakers facing this 21st century problem.  The Times blog and its accompanying article are both great reads on this fascinating – and for some anti-noise activists, frustrating – topic.

The Japanese Environment Ministry is gearing up for the April launch of a nationwide field survey around all 1500 wind turbines in operation in the country.  Prompted by health complaints by some neighbors, the survey will the first such comprehensive study of the question; low frequency and audible noise will be recorded, to see whether there is any correlation between these sounds and the reported effects.  According to the ministry plan, the survey will first ascertain whether there have been problems reported in the vicinity of wind turbines. If residents complain of health problems, their symptoms will be examined. Measuring equipment will be placed in their homes to find out the relationship between the turbines and health problems. The distance between the turbines and homes as well as geographical features of the area will also be examined. About 30 of the nation’s 376 wind farms (1-20 turbines each) have prompted formal complaints to date.  For more, see this Japanese news report.

In what could be a precedent-setting move, the Ontario Assessment Review Board (ARB) has slashed the taxable value of a house because of noise from a transformer station across the street.  The transformer, which site 360 meters (about 1200 feet) from Paul Thompson’s home, produces a constant hum of about 40dB in Thompson’s home.  In 2008, the Municipal Property Assessment Corp. assessed the 1,320-square-foot house at $255,000; Thompson felt that assessment may be fair if not for the noise from the recently-installed substation, and appealed.  According to an article in the Home section of the Toronto Star, Thompson introduced evidence at the hearing showing that the transformer station noise was audible within the house with the windows closed. He described the noise as a “nightmare” and a constant nuisance that not only affects his day-to-day activity, but also impacts the sales value and marketability of his property. In reaching its decision to cut his assessment in half, board member Marques wrote, “The Board finds that the constant hum alleged by Mr. Thompson does exist and significantly reduces the current value of the subject property. The best evidence is the audio portion of the CD (Exhibit No. 1) and the testimony of both parties. ”Having heard this nuisance, apparently sanctioned by the Municipality, the Board accepts Mr. Thompson’s testimony that the stigma of noise contamination has a negative impact on the value and marketability of the property, and that after learning of the hum, prospective purchasers will quickly lose interest in purchasing the property. The Board is satisfied that a very substantial reduction is warranted.”

It is especially interesting that the ARB felt that Thompson’s home value was so dramatically affected by sound of 40dB; many municipalities c0nsider this and higher levels to be acceptable.  Wind turbine noise, while varying widely with wind conditions, can be 45dB or higher at similar distances (1000-1500 feet), and remain above 35dB for up to a mile.  As Bob Aaron, a real estate lawyer and author of this article, notes: “Thompson’s successful appeal of his assessment is only the first of many similar cases that are certain to follow. The result, of course, will be a significant reduction in the tax base of municipalities like Amaranth, which play host to wind turbine farms.”  This hearing took place in September 2008, but only recently came to light.  Bob Aaron has posted the ARB decision on his website.

This recent article in the London Times is a great read for those of us interested in natural quiet and the effects of humans sounds on people.  Helen Rumbelow was sent on a seasonal assignment by her editor: find a place in the England where one might experience a “silent night.”  She travels to places recommended on the official UK Noise Map, visits researchers, and reflects on her own quest to find quiet.  It written in a light, amusing tone and well worth a read.  Among the more sober point made by those she visited:

• Deepak Prasher, Emeritus Professor of Audiology at University College London, a world expert on noise nuisance and health, reminds us that “ if noise is continuous it places great stress on the body. People think they adapt but actually all that happens is they get used to the idea of living within noise. Their body doesn’t get used to it…We need to have an awareness that noise isn’t good for us. We have acknowledged it for air pollution but noise pollution goes together with that.”
• Professor Jian Kang of Sheffield University notes that among visitors to the Sheffield Peace Garden, those with a university education found it noisier than those without, a point that is part of a larger trend: “Reducing noise gets more important as affluence increases,” says Kang. “Many years ago, noise was regarded as a sign of development and was therefore tolerated as something from which we all benefited.” In countries that are still growing apace, such as Kang’s native China, they are still as tolerant of mechanical noise as we were in the 1960s. But in the West, our sense of beneficial connection to such noise has been broken.

In early December, the Association for the Protection of Ménez, Quelec’h and Saint-Gildas won a groundbreaking court case in France, in which the Court of Appeals of Renne ordered that eight wind turbines in Cast and Châteaulin be shut down from 10pm to 7am.  The Association had sought court relief from night time noise disturbance in the area around the wind farm.  News coverage is spotty: here is a brief summary of the case, and here is a French news story, crudely translated by Google.

See more AEInews coverage of wind turbine noise issues

It’s a beautiful idea, come to fruition: in the island communities of Vinalhaven and North Haven, Maine, a local electrical co-op joined forces with a regional nonprofit organization, and built three large wind turbines which would provide the 2,000 households on the island with locally-produced power.  On a lovely fall day in November, the largest group of island residents ever gathered in one place celebrated the commissioning of the Fox Islands Wind Project.  But for some residents, the moment they had been waiting for had an unexpected element: clearly audible noise.

“As I watched the first rotation of the giant blades from our deck,” says Sally Wylie in the island newspaper, The Working Waterfront,  ”My sense of wonder was replaced by disbelief and utter shock as the turbine noise revved up and up, past the sound of our babbling brook, to levels unimagined. It was not supposed to be this way! During informational meetings, on the Fox Islands Wind website, in private conversations, and with personal correspondence, we were all told that ambient noise from the surrounding area would cover the sound of the turbines. This was our expectation….We have found that the 45 decibel limit that is designated as ‘quiet’ in Maine, is truly a cruel joke. On our quiet cove, we now know that 45 decibels is loud.”

The community came together to dream and build the turbines, and now they are working together as well to address unexpected noise issues.  Starting the day after commissioning, representatives of the wind project visited neighbors, deployed microphones, trained neighbors in how to record sound and wind speed, and asked neighbors to keep diaries of their experience of the noise.  Also writing in The Working Waterfront, board members of the local electric co-op and the Fox Island Wind LLC, formed to take advantage of tax credits available for wind development, affirm  that they are “committed to monitoring the sound impacts beyond the traditional approach of measuring wind speeds and decibel levels, as we have asked neighbors to also document their subjective experiences so that we can determine any other factors they may be finding bothersome. In a wide variety of ways, the Fox Islands Wind project has been a very different, first-of-its-kind, model wind project. We are committed to dealing with the sound issue in the same open and participatory way that we have approached the project since its inception.”

Once again, the experience of people on the ground, and initial recordings and conversations with neighbors, suggests that the noise is most troublesome within a half mile of the turbines, with some lesser effects out to a mile or more. According to Fox Islands Wind, “it does not appear that, except in a few individual spots, there is much impact beyond a half mile from the site.”  Wylie’s conversations and recordings suggest to her that “households within a mile to a mile-and-a-half radius of the turbines are impacted by the sound.” The commentary here at AEInews is beginning to sound like a broken record, but here we go again: it is clear that we will need to make some social choices about the degree of disturbance we are willing to trade for the benefits of renewable wind energy.  There is little doubt that homes within a half mile of turbines often experience elevated noise levels, and beyond that distance, impacts diminish in frequency and severity.  Where will we decide to draw the line?

Fox Islands Wind Project website

The Working Waterfront, visit for ongoing coverage of the story

Island Institute community energy web info, including article on offshore wind and column in Working Waterfront on the genesis of the Fox Islands Wind project, including its economic justice/equity goals.

Download a Word doc version of this commentary

A report issued by the American Wind Energy Association (AWEA) and the Canadian Wind Energy Association (CanWEA) purports to assess all currently available research on the health effects associated with exposure to wind farm noise, and concludes that there are no such problems.  The report, funded by North America’s two key wind industry trade organizations, centers on the symptoms of the reported “wind turbine syndrome,” and while it offers a robust critique of the idea that low frequency noise from wind farms can cause direct health impacts, it’s hard to take its message of wind’s “clean bill of health” at face value, thanks to many topics that are ignored or underplayed.  The report minimizes the levels of annoyance and impacts on quality of life reported in other studies, and completely omits any assessment of the most widely reported health-related impact of living near wind farms, sleep disruption. (For more complete assessments of health-related issues related to wind farms and noise, see recent reports from the Minnesota Department of Health report and World Health Organization.)

The authors of the new AWEA/CanWEA report acknowledge that some people may be annoyed by the sounds of wind turbines, but stress that annoyance is not an “adverse health effect.”  They also seem intent on assuring that any mention of annoyance rates is kept to 10% or below, which necessitates some creative re-interpretation of one of their key sources, a recent paper by Eja Pederson that compiled results from three surveys near wind farms in Scandinavia, summarized in October by AEI. In particular, they combine results from two studies in rural areas and one in a suburban area, which Pederson explicitly presented separately, because they illustrate that annoyance rates are far higher in rural areas (since the suburban study had more participants, the overall average is dominated by the suburban results).  In AEI’s view (as regular readers will know), the bottom line in all annoyance studies is that while many (or even most) people who are within earshot of wind turbines are not strongly affected by the noise, a substantial minority (ranging from 5-40% depending on how close they live) are negatively impacted, sometimes to the point of abandoning their homes; our challenge is to decide how many people we feel OK disrupting, and regulating wind farm siting to match that choice.

The report also repeatedly states that “the sound emitted by wind turbines is not unique,” while it elsewhere briefly acknowledges the often fluctuating nature of turbine noise (amplitude modulation) and its role

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A detailed statistical analysis of 5000 homes sold within ten miles of wind farms has failed to find any clear relationship between sales price and proximity to, or views of, industrial wind farms.  However, close reading of the results raises some questions about trends within a mile of turbines, and the authors recommend more detailed study of the closest homes as a top priority for future research.  Co-author Ryan Wiser affirmed that “It is possible that individual homes have been impacted, and frankly, I think it would be a bit silly to suggest otherwise. Human development impacts property values.”

As I look closely at the result, it seems likely that the apparent trend toward some property value effect largely mirrors surveys of residents near wind farms.  The “problem” in interpreting this data and the surveys is that there is NOT a universal increase in annoyance or sleeplessness or dropping property values as you move closer to turbines; rather, there is an increasing MINORITY of neighbors who are negatively impacted.  Several earlier posts address this factor: from 10% of neighbors at around a mile or so, increasing to 25% or so at a half mile, and perhaps 40% at a quarter mile, survey results reflect the well-known individual variability in susceptibility to noise.  It seems clear that the “small and infrequent” numbers of homes negatively affected in the study addressed here, are mostly concentrated near turbines, and may represent a similar percentage of landowners as report sleep disturbance and other noise impacts.  If so, the 5% average price hit is apt to represent a much larger valuation drop in a quarter or so of the homes that are within a mile.

The study, funded by the US Department of Energy at the Lawrence Berkeley National Lab, took into account size and other features of the homes, and looked particularly for any trends in prices resulting from views of wind turbines, having turbines in the vicinity (1-5 miles), and nuisance factors like shadow flicker and noise.  This third focus is the one of most interest to AEI, and we took a close look Read the rest of this entry »

Two Maine towns grappling with crafting wind farm ordinances are pushing the envelope on setback requirements.  In November,, voters in Dixmont, where plans were afoot to place turbines atop the 1165-foot Mount Harris, approved a 1-mile setback requirement by a large margin.  A story in the Portland Press Herald provides a good overview of the forces behind this vote, and the ripples it is causing in the wind industry.  From the Press Herald story:

Dixmont’s farming heritage is reflected in its forests and open fields, but the town has become a rural bedroom community for Bangor, Newport and Waterville. There are few local businesses; the elementary school is the largest employer. So when developers began measuring wind speeds atop Mount Harris, Hog Hill and Peaked Mountain, some residents saw the chance to lower taxes through revenue collected from renewable energy. Others, however, saw their town with no protection from industrial development. That led to a moratorium on wind projects last November, while the town crafted rules.

What followed was a deliberate process in which the Planning Board studied wind power ordinances in other states and countries, as well as Maine’s model ordinance. The town encouraged residents to make the half-hour drive to Freedom, where they could stand under the whirling blades on Beaver Ridge. Some residents even visited the wind farm at Mars Hill in Aroostook County. Several townspeople spoke to homeowners next to these projects. Among the messages they heard is that the turbines disrupted abutters’ lives. Complaints ranged from noise and visual flicker to health effects that some people blame on living near wind farms. These anecdotes seemed to have a decisive impact, said First Selectman Judy Dann. “I think people listened to the stories that these people had to tell,” she said, and helped convince a majority that wind turbines weren’t a good fit for Dixmont.

Meanwhile, the selectmen in Jackson unveiled a 56-page draft ordinance that includes several unusually far-reaching elements. Setbacks are proposed to be 13 times turbine height, which would come to just under a mile for 400-foot turbines; current industry norms are closer to 300 feet, which would create setbacks of about three-quarters of a mile (likely to avoid nearly all noise complaints, based on recent reports of problems at other wind farms, and several larger research studies of annoyance and sleep disruption around wind farms).  This would require energy companies to negotiate with all families in that large zone if they wanted to obtain waivers, which would also be allowed. The Jackson ordinance will be put to a local vote after the selectmen consider it more fully.

Meanwhile, the Friends of Lincoln Lakes filed a legal brief supporting their appeal of the August decision of the Board of Environmental Protection (BEP). At that time, the BEP affirmed the April 2009 Order of the Department of Environmental Protection, granting a license to First Wind for the construction of the Rollins Ridge Industrial Wind Farm in Lincoln and surrounding towns. The brief questions the adequacy of the noise standards as well as the modeling used to assure compliance with the noise standards. Download full brief here.