The Petiitions Committee of the Welsh Assembly, which includes members from four diverse political parties, has issued a report on its investigation of wind farm noise in Welsh communities. The report is short but concisely comprehensive in considering input from residents with noise complaints, advocates of wind energy, and wind developers. The committee suggests that in deeply rural areas, it may be necessary to “increase the (standard 500 metre) separation distance as appropriate, and in specified circumstances up to 1500 metres, according to environmental factors such as the topography and the ambient noise levels of the area.” Sleep disruption was a major factor in complaints, and in the Committee’s recommendations, which quoted a recent editorial in the British Journal of Medicine, written by sleep expert Christopher Hanning. After hearing reports of faulty turbines making grinding noises for weeks before being repaired, the Committee also recommended immediate shut down of those turbines, at least at night, until repairs can be made.
For a welcome change of pace from stories about contentious acoustic ecology issues, check out this column from Australia about a group of people who were treated to two sessions of whale song while floating near their inflatable raft. Here’s a teaser:
“This time the singer was right before my eyes, and the singing was so powerful you could actually feel it in the water. As I drifted on the surface, the sound vibrated through my body. It was an amazing experience.”
(Update alert): Queensland Health joins other Australian govts in recommending 2km (1.2 mi) wind farm setbacksHealth, Human impacts, News, Wind turbines No Comments »
UPDATE, 5/31/12: The article in The Australian that spurred this post has triggered a quick back-and-forth in the couple days since it was published. First, this article implied it was nothing more than a renegade staffer speaking without understanding the issue, quoting a Queensland Health spokesman as saying the Department has not issued any new guidance on wind farms, and insisting that a National Health and Medical Research Council (NHMRC) short “rapid review” statement remains the relevant document. But this was quickly followed by a very clear statement from the Chairman of the NHMRC team currently doing a more in-depth study of the issue of health issues near wind farms; the Chair, Bruce Armstrong, affirmed that it’s “entirely appropriate to adopt the precautionary principle where it is neither possible to say with any certainty there is a problem nor is it possible to exclude with any certainty the existence of a problem.” And, a further statement from Queensland Health also endorsed the letter, saying “Our letter to the Tablelands Council was to advise council of the NHMRC guidelines and the fact that these guidelines are being reviewed by NHMRC.”
The author of the original letter, David Sellars, is a Director in the Environmental Health Branch, which deals with “health risk assessments of environmental hazards,” and currently directs the Tropical Regional Services office, which focuses on health of populations, rather than individuals. So, it appears the Mr. Sellars was not operating outside his area of responsibility. It remains unclear whether, as stated in the “Climate Spectator” column that ran the initial “retraction” of the statement, Mr. Sellars well-versed in the state of research on the issue. The second Departmental statement certainly confirms it’s more than his personal opinion.
So, with all that in mind, here’s the bit that triggered such a quick and chaotic response:
Queensland Health has become the first government health agency to recommend a “cautionary” approach to wind farm siting, urging the Tablelands Regional Council to maintain a 2km (1.25 mi) buffer between new wind turbines and residences. Tablelands is considering an application for an 80-turbine wind farm, nine of which are within 2km of homes.
Despite the fact that the proposed Mount Emerald wind farm would meet existing noise criteria, Queensland Health noted that “Research into the potential health effects of wind turbines is ongoing and is being undertaken on an international scale.” A 2km setback would likely nearly eliminate health effects triggered by sleep disruption and greatly reduce stress-related health effects that have been increasingly reported by some residents living near wind farms. Many wind farm neighbors also note physical sensations that they attribute to infrasound and low frequency noise, which would be also be reduced at 2km.
Queensland Health’s director of environmental health, David Sellars, said the National Health and Medical Research Council was reviewing its position on the possible health effects of wind turbines and was aiming to release a public statement by the end of the year. “Queensland Health would be likely to be guided by the NHMRC statement, resulting from this research,” he said. “Until such time, Tablelands Regional Council is encouraged to take a precautionary approach to development applications of this type.”
Mr Sellars noted that the Victorian governments recently adopted planning guidelines, which ban wind turbines within 2km of homes, could be considered current best practice from a cautionary perspective. New South Wales is currently considering similar draft guidelines, and in South Australia, noise levels are limited to 35dB in areas “primarily intended for rural living,” which in effect creates nearly as much setback from homes.
Further update, 5/31/12: The Mayor of Tablelands has said that it’s likely the local council will await the publication of the new, more comprehensive report from the NHMRC before making a decision on local wind farm siting standards. “I think councillors would be very interested to see the outcomes of that before they vote on anything,” said Mayor Rosa Lee Long.
Meanwhile, Ratch Australia, the developers behind the Mt Emerald wind farm proposal, insist there is no rationale for the 2km set-backs enforced elsewhere in the country. “Every site is unique and there is no scientific consideration that justifies the set-back,” the company said in a written statement.
(Ed. note: There is no scientific justification for any common setback standards that govern exactly how far from homes wind turbines can be placed; if it was only about pure science, noise limits would be based on levels that cause physical injury, such as those used in workplace safety laws. Rather, wind farm siting standards are based on local tolerance for noise nuisances, which can never be scientifically determined (though of course we can, over time, get a sense from experience elsewhere to help inform new decisions). 2km standards are generally based on the idea that turbines will only rarely be heard beyond that distance at levels that cause strong annoyance or sleep disruption; the same could be said for other possible distances, since of course topography and atmospheric conditions lead to differences in sound propagation. A reasonable case could be made for any distance from 500m to 3km, depending on how far an ordinance is trying to go toward minimizing the sound level of turbines at homes. 2km is aiming to avoid sound levels loud enough to be intrusive to the more sensitive among local residents, while in most locations, it will not mean turbines are always inaudible.)
The Falmouth Board of Health held a special meeting to gather written and oral testimony from neighbors of three wind turbines in town who are experiencing health issues. Seventy people attended the meeting, with about 30 having prepared written testimony about their personal health after the turbines became operational, as requested by the board, which the Board will submit to the Massachusetts Department of Health. While one resident who lives 3000 feet from a turbine testified that he had noticed no ill effects, most of those attending shared specific symptoms and incidents. Many of these related to sleep disruption and resulting headaches or lack of concentration, including Mark Cool, an air traffic controller who had the first near-accident incident in his career after losing sleep due to the turbines. Some spoke of physical sensations, a “pressure” that they suspect is triggered inaudible infrasound (though may be caused by air pressure pulses in down-wind turbine wakes). Most of those in attendence seemed to agree with Diane Funfar, who said, “turn these tortuous machines off.”
One of the two town-owned turbines has been shut down after it was found out of compliance with state noise standards on quiet nights, and is being tested to see if it is in compliance during the day; the other town-owned turbine is currently running only in the daytime while efforts are underway to find a local consensus on how to proceed. Seventy neighbors in forty households want them shut down completely while the consensus process is underway, and recently chose not to participate in the initial planning of the consensus process, which is set to get underway in June.
One of the contentious wind turbines in Falmouth, Massachusetts has been ruled out of compliance with state noise rules after an investigation by the state Department of Environmental Protection. The noise study found that the turbine created noise levels at one residence less than 1500 feet away that exceeded background ambient noise by more than 10dB, which the agency described as “unacceptable to local residents.” Residents reported a sense of vindication at the finding, and the town has shut down the turbine; the town had already agreed to shut their second turbine down at night while seeking a community-wide consensus on moving forward. Todd Drummey, 48, a financial planner who lives 3,000 feet from the closest turbine in Falmouth, compared the noise of the turbines to jets and pile drivers, depending on the weather. He said shutting them down, at least temporarily, was a good first step. “But what I would really love to see is that they’re moved,’’ he said, adding he also has trouble sleeping at night.
DEP officials stress that the finding should not be seen as evidence of a more widespread noise issue, noting that turbine designs and topography vary from project to project. In particular, the offending turbine is an older-style “stall-regulated” design (in which blade speed is controlled by tilting the three blades away from the wind), which is louder in high winds than “pitch-regulated” turbines, in which each blade rotates while remaining in their original shared plane. Falmouth officials suggested that they may do some daytime testing of the offending turbine, to see whether it can join the other unit and operate within 10dB of ambient during the day (the DEP tests focused on the quietest times of the night).
In looking over the DEP’s report, what jumped out at me was that while at only one of the five locations tested by the DEP did the turbine sounds consistently exceed ambient by over 10dB, at every location, the average peak turbine sound was at least 5dB louder, and in 10 of the 12 individual testing sessions, the turbines were more than 7dB louder. This points to the subtle yet important question of what is used as a standard; many acousticians consider 5dB a difference that is likely to trigger widespread complaints, with 10dB likely to lead to significant problems. New York State noise law aims to keep noise sources from exceeding a 6dB difference. Yet the more substantial 10dB difference has been widely adopted as a standard, and could be one factor in seeing more noise complaints than might be expected by project planners. One more subtle but rarely considered factor is that while 3dB is considered a difference that is just audible over a similar ambient background, noise sources with different frequency spectrums than current background levels can be perceived at a few decibels below ambient, as could be the case with quiet night time conditions and a turbine sound spectrum heavy in lower frequencies; this could accentuate the audibility of turbines in some conditions, making a lower “dB over ambient” standard more likely to serve the intended purpose of minimizing audibility, annoyance, and complaints.
The US Navy has released its initial Draft Environmental Impact Statements for the next 5-year round of permits it will seek from the National Marine Fisheries Service for its at-sea training activities, and the numbers of animals expected to be affected have skyrocketed. This is in part thanks to the new EISs combining areas that were dealt with separately in the first round of permitting, which occurred after the NRDC challenged the lack of permits in court. The new Hawaii-Southern California EIS not only combines these two previous separate areas, but also accounts for impact to animals in waters between Hawaii and California that were previously not considered. In addition, the new EISs draw on more recent scientific evidence of lower impact thresholds for some species, including beaked whales, and on more advanced models that predict animal concentrations and movements.
While this expanded focus and better data is a valuable step forward, the numbers of animals expected to be injured or to have their behavior affected has increased so much that NRDC termed it “harm of staggering proportions.” Clearly, attempts to foster more constructive dialogue between the Navy, NMFS, and NRDC during the EIS process has not led to a shared vision or lowered the heat all that much. The Navy’s estimate of the number of animals whose behavior could be affected has jumped from 770,000 to 14 million, including 2 million cases of temporary hearing impairment, in addition to 2000 animals experiencing permanent hearing loss. And, the Navy estimates that explosives training and testing could kill 1000 animals.
But, Navy officials told CNN, these alarming numbers — a result of mathematical modeling — are worst-case scenarios. “We believe … with our mitigation efforts and the Navy commitment that those injuries and mortalities will be none,” said John Van Name, U.S. Pacific Fleet senior environmental planner in Pearl Harbor, Hawaii. The report also indicated monitoring in 2009-2010 off Hawaii and Southern California showed 162,000 marine mammals with no evidence of distress or unusual behavior during Navy activities. By comparison, the previous round of EISs estimated injury or death to about 100 animals in Hawaii and California during the five years from 2009-13; to date, two or three dolphins are known to have been killed by explosives testing.
Zak Smith of the NRDC responds that “I am not saying they are not well-intentioned. But I am not sure their choices make them the best environmental stewards they could be.” In a blog post, Smith elaborates:
While the Navy’s understanding of how much harm it’s activities cause marine mammals has increased, it hasn’t taken any corresponding steps to minimize this staggering level of harm. It’s mitigation protocol remains largely unchanged, with the Navy refusing to set aside areas of high marine mammal density where sonar should not be used. This means sensitive breeding and foraging habitats and biologically unique areas within the training area can still be used for sonar and underwater explosives training. We know that safeguarding specific areas of sensitive habitat is the best way to lessen harm to whales and dolphins from sonar and other activities — don’t use the technology in the same areas where whale and dolphin numbers are high or during breeding seasons. Faced with such incredible numbers and levels of harm, the Navy must do more to identify and set aside portions of its training areas (areas often the size of large states, like California) where it will not conduct training and testing.
Permits issued by National Marine Fisheries Service to allow seismic surveys in Alaska’s Cook Inlet have been challenged in Federal Court. Cook Inlet is home to a dwindling population of beluga whales (under 300), and the permits allow behavioral harassment of up to 30 belugas per year. In part, the challenge contends that this likely underestimates the impact, as, “NMFS based its analysis on an unrevised, outdated, 15-year-old assumption about take levels that some of the world’s leading bioacousticians recently urged NMFS to discard – and that ignores the only existing study of airguns and belugas, showing impacts at far greater distances than NMFS has predicted here.” Saying that the Marine Mammal Commission recommended against issuing the permits, the suit claims that NMFS erred in its finding of “no significant impact.”
In addition to three environmental organizations, the Native Village of Chickaloon is party to the lawsuit, saying that NMFS did not fulfill necessary consultation with the tribe, and noting that while the tribe is barred from its traditional hunts due to declining beluga numbers, the permits allow oil and gas development to put whales at risk.
The suit claims that an Environmental Impact Statement should have been prepared, rather than a less comprehensive Environmental Assessment. As covered in previous AEInews posts over the past four years, NMFS has declared parts of Cook Inlet to be essential habitat for the belugas, though the 180-mile long inlet continues to bear the brunt of substantial industrial activity, including the Port of Anchorage and ongoing oil and gas development.
Vermonters for a Clean Environment have filed a complaint in US District Court challenging the Forest Service’s planned permit for 15 new wind turbines in the Green Mountain National Forest. The challenge includes several issues, but centers on the visual and sound impact of the new turbines on the nearby George D. Aiken Wilderness. Sound monitoring and modeling indicates that the boundary of the Wilderness is one of two areas in which the new turbines are likely to be audible above existing background sound levels (which includes sound from several older turbines near the new project site).
The recent court filing is not yet available on the group’s website, but an earlier appeal submitted to the Forest Service contains many of the same arguments. A central point is expressed this way:
If the mechanical sound of the wind turbines can be heard within the George Aiken Wilderness, it is no longer a wilderness, plain and simple. See, e.g., 16 U.S.C. § 1131(c) (requiring that the area “retain[ ] its primeval character” and requiring that the “the imprint of man’s work [should be] substantially unnoticeable”).
The complaint suggests that ridgelines in the Wilderness will have more visual impact than the Forest Service documented, and there was not a sufficient assessment of how far into the wilderness sounds may be audible. The permitting documents estimates that turbines will be 5-7dB louder than background sound at the Wilderness boundary, and will be less audible as you move deeper into the wilderness; these figures are long-term (day-long or night-long) average sound levels.