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Follow SOCAL D-tag and controlled exposure field work at SEABlog

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SOCAL BRS tagging from sideAs usual, Brandon Southall is posting regularly from sea as his research team begins the third year of a five year Behavioral Response Study off the coast of southern California.  The field work is largely focused on conducting controlled exposure experiments (CEE) on a fairly wide variety of species, in order to learn more about how each species responds to various types of sounds.  Animals are approached in zodiacs in order to attach Dtags (temporary suction-cup tags that record sounds heard and produced by the animal, as well as detailed three-dimensional dive patterns) or one of several other types of tags; once the tag has been on long enough for the animal to relax after that tagging approach, a larger ship maneuvers in to position and transmits sequence of test sounds.  So far, test sounds have been a simulated mid-frequency active sonar signal (peaking at 25dB quieter than the Navy uses) and a pseudo-random noise stimulus. For background on this year’s study objectives, see the SOCAL-12 informational webpage.

In addition, researchers on the cruise pursue other related studies, including ongoing visual observation surveys, tests of new acoustic monitoring systems, and trials of new research methodologies for monitoring behavior of non-tagged animals for possible future exposure studies. A summary of last year’s field work can be downloaded at the SOCAL-11 website; SOCAL-11 succeeded in attaching 38 tags of four different types on 35 individuals of four different marine mammal species. For the suction cup acoustic/position tags used in SOCAL?11 (not including the satellite tags), this resulted in nearly 200 hours of tag data across these individuals, the majority resulting from Dtag deployments.  Thirteen complete CEE sequences were conducted, involving 13 blue whales, 4 Risso’s dolphins, and 1 Cuvier’s beaked whale. Preliminary analysis of dive patterns suggest that blue whales and Risso’s dolphins showed little response to the sounds (though the dolphins were resting at the surface during the CEEs; deep diving behavior has not been taking place during CEE’s so far), while the beaked whale showed “a similar relatively strong response at low received level (ed. note: peak of 135-140dB re 1 uPa, with behavioral response initiated when the signal was not much above background ambient) as was observed in SOCAL-10.”

Mediterranean fin whales displaced by oil and gas noise

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Ongoing acoustic research in the Mediterranean has confirmed earlier indications that fin whales are far more affected by oil and gas exploration noise than has long been assumed. Manuel Castellote’s most recent paper details a set of disturbing findings, here summarized by the website Science Codex:

Maritime traffic and geophysical exploration –including the search for hydrocarbons– “drastically” reduces the song effectiveness –linked to reproduction and which propagates hundreds of kilometres beneath the Sea– of the whales, which are also the group of marine mammals with the greatest acoustic sensitivity at low frequencies. “The noise generated through human activity in the oceans leads to possible chronic effects on the health of this species”, Castellote states.

After analysing 20,547 hours of recordings of the sounds emitted by the whales, the study published in Biological Conservation indicated that the whales modified the characteristics of their songs in order to try to reduce the impact of noise on their propagation. In addition the researchers recorded a massive displacement of fin whales, triggered by the noise from geophysical prospecting at a distance of 285 km from the study area. “These recurrent displacements, together with the changes in acoustic behaviour, could increase the energy expenditure and reduce the reproductive success of whales affected by the noise”, the expert indicated.

In the long-term the consequences for these mammals are clear: chronic effects which impact on their survival emerge. “Noise in the marine medium, despite being recognised as a significant pollutant, is far from being controlled and regulated within the waters of the Exclusive Economic Zone of Spain”, warns Castellote

Follow the Falmouth Wind Turbines Options Analysis process

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The town of Falmouth, Massachusetts has been the site of some unusually wide-ranging efforts to come to grips with the unexpected impacts on nearby neighbors after two town-owned turbines began operating at the local wastewater treatment plant.  Several dozen neighbors, most living within a half mile or so, have spoken out consistently about their experiences with turbine noise, leading to an evenly split town meeting last spring in which about half the town meeting voters asked that the turbines be shut down, and half urged the selectmen to pursue a collaborative process to come up with a solution to the problems.

In response, a committee was formed to come up with a set of options to offer to the selectmen, hopefully in time for the fall town meeting, though it may take longer.  The process is being facilitated by the Consensus-Building Institute, which has created a website where you can track the progress of the committee. Here you can find generalized meeting minutes (usually available within three weeks after each meeting; look for items called “Final Meeting Summary” under each date), presentations made at meetings, and some outside documents, including the full collection of testimony from over forty residents submitted to the Falmouth Board of Health when it held a hearing on the issue.   In addition, local public access TV is making videos of all meetings available; links to these videos appear on the CBI page as well. 

As laid out by the group as it began its process, the core interests at stake include the following, with the understanding that any broadly acceptable long-term plan for the turbines will need to respond to some extent to all of these core interests:

  • Health, safety and well-being of impacted abutters
  • Property rights and economic impacts on property for abutters
  • Implementation of Falmouth’s climate action protection plan goals to reduce use of fossil fuel
  • Fiscal impacts on the town’s taxpayers and town services
  • An amicable end to a conflict that has divided and challenged the town’s relationships and reputation

The participants have been selected to represent the following interests:

  • 5 residents primarily concerned with adverse impacts of the turbines on neighbors, including health and economic impacts
  • 2 residents primarily concerned with implementing Falmouth’s climate action protection plan to reduce use of fossil fuel
  • 2 taxpayers primarily concerned with the Town of Falmouth’s fiscal well-being
  • 2 residents with strong empathy for all perspectives. These representatives are primarily concerned with a fair and effective process that may lead to an amicable outcome and reunite the town
  • 3 Town Departments
  • 2 liaisons from the Board of Selectmen attend all meetings and are available to answer questions, but do not participate at the table

New Maine wind farm spurs a dozen complaints around lakes

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Ten wind turbines in Woodstock, Maine began operating last December, and now that summer camps are occupied on two local ponds, noise complaints are starting to roll in from up to a mile and a half away.  The turbines are more than three-quarters of a mile from any homes; a few homes (perhaps 10) are within a mile, and another dozen or so are within a mile and a half (see location map). So far, Woodstock’s wind ordinance committee has received more than a dozen letters of concern about unexpected noise impacts, a number that would seem to represent a significant proportion of residents within that area.  The Bethel Citizen recently published a very lengthy article detailing many of the neighbors’ experiences, as well as responses from the state Department of Environmental Protection and the wind farm owners.  Among the highlights:

ME spruce mountain wind farm from concord pond 1 5mi copyOne year-round resident notes that the noise is loudest when his home is downwind of the turbines, and adds, “What is most interesting to me is that they seem loudest on the calmer days.  That is, if the wind is barely existent, I can really hear them roaring.”

A woman with a camp on Shagg Pond said that on the Friday before July 4th holiday, “The noise was so horrific at my camp that I couldn’t stay outside,” she said, saying she had suffered headaches. “It sounded like an airplane that never left the top of my house.”

A permanent sound monitor installed 2000 feet from the Spruce Mountain Wind (SMW) property line between the last turbines and Shagg Pond had its wires chewed by mice, so has not been collecting data recently.  While SMW had earlier applied to the state DEP to discontinue routine monitoring, and instead respond only to specific complaints, that application was recently withdrawn.  Earlier monitoring data, as well as spot checks after two complaints (one in February and one in July) showed that the project was operating within its permit conditions of 55dB in the daytime and 45dB at night.  Ed. note: once again, we may be looking at an example of a high permitted level leading to intrusive noise conditions (well above other sounds) even when in compliance; in addition, if there are compounding factors that cause higher sound levels in conditions hard to identify or replicate (e.g., unusually high degree of inflow turbulence), a short spot check may not catch the same noise conditions, even if winds are from the same direction and speed.

The Woodstock committee charged with drafting a town ordinance to govern future wind farm construction had been considering a 1-mile setback as one possibility.  Given the recent complaints, committee chairman Bob Elliott said they may need to consider larger setbacks, lower noise limits, or both. In addition, they are considering a requirement that project developers fund an escrow account to allow the town to hire its own consultants as needed.

UK tax authorities affirm property value loss near some wind farms

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The UK Valuation Office Agency has begun setting some new precedents by approving property valuation reductions for some homes near wind farms. It appears that only a few properties have been downgraded so far, and it is unknown how many such requests have been submitted and denied.  As reported in The Telegraph:

In one recent case a couple saw the value of their home 650 yards from the Fullabrook wind farm near Braunton, Devon, fall from £400,000 to £300,000 according to a local agent’s estimate. The couple, who were not attempting to sell their house, told the VOA that the persistent whooshing noise caused by the turbines and the visual intrusion – including a flickering shadow when the sun is directly behind the blades – made their property less valuable. The VOA accepted their argument and agreed to move the property from council tax band F to band E, amounting to a saving of about £400 a year, the Sunday Times reported (subscription required).

The Sunday Times story goes on to note that the VOA has received other applications for property value reductions near wind farms, though the number is unclear because only those reaching appeal are made public.  At least three other properties have had reductions approved, though factors other than sound alone reportedly came into play.  At least one successful appeal, by Jane Davis, came after real estate agents refused to even list the property she had moved away from because of wind farm noise.  

Whales can dampen hearing: implications for ocean noise concerns

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You may have noticed a recent flurry of press reports about research in Hawaii that begins to quantify a long-suspected quality of cetacean hearing: the ability to dampen hearing sensitivity so that loud sounds don’t cause damage.  Given the extremely loud volume of many whale calls, which are meant to be heard tens or hundreds of miles away, researchers have long speculated that animals may have ways of protecting their ears from calls made by themselves or nearby whales, perhaps using a muscle response to reduce their hearing sensitivity (not unlike a similar muscular dampening mechanism in humans).  Indeed, earlier studies by Paul Nachtigall’s team had found that some whales could do indeed reduce their auditory response to the sharp clicks they use for echolocation.  In the new study, Nachtigall trained a captive false killer whale named Kina to reduce her hearing sensitivity by repeatedly playing a soft trigger sound followed by a loud sound.  Eventually, she learned to prepare for the loud sound in advance by reducing her hearing sensitivity.  “It’s equivalent to plugging your ears…it’s like a volume control,” according to Nachtigall.

Well, that sounds like a pretty useful trick, given all the concern about human sounds in the sea.  And the media, led by the New York Times, jumped on board with headlines following on the Times‘ assertion that suggested whales  already “are coping with humans’ din” using this method. (Among the exciting headline variations: Whales Can Ignore Human Noise, Whales Learning to Block Out Harmful Human Noise, and UH Scientists: Whales Can Shut Their Ears.)

Oops, they did it again!  Grab some interesting new science and leap to apply a specific finding to a broad public policy question, often, as this time, giving us a false sense of security that the “experts” have solved the problem, so there’s no need to worry our little selves over it any more (as stressed in this NRDC commentary).  To be fair, the Times piece included a few cautionary comments from both scientists and environmental groups, but the headline rippled across the web as the story was picked up by others.

Two key things to keep in mind:  First, this whale was trained to implement her native ability, meant for use with her sounds or those of nearby compatriots, and to apply it to an outside sound made by humans.  This doesn’t mean that untrained whales will do the same.  

And second: If whales can dampen their hearing once a loud sound enters their soundscape, this could indeed help reduce the physiological impact of some loud human sounds, such as air guns or navy sonar. If indeed this ability translates to wild cetaceans, the best we could hope for is that it would minimize hearing damage caused by occasional and unexpected loud, close sounds that repeat.  There would be no protection from the first blast or two, but perhaps some protection from succeeding ones; or, if the sound source was gradually approaching or “ramping up,” as often done with sonar and air guns, animals may be able to “plug their ears” before sounds reach damaging levels, if for some reason they can’t move away.  Even then, the animals are very likely to experience rapidly elevated stress levels, as they would be less able to hear whatever fainter sounds they had been attending to before the intrusion. Yet research in the field suggests that most species of whales and dolphins prefer to keep some distance from such loud noise sources; this hearing-protection trick doesn’t seem to make them happy to hang around loud human sounds.  

Most crucially, these occasional loud sounds are but a small proportion of the human noises whales are trying to cope with. Noise from shipping, oil and gas production activities, offshore construction, and more distant moderate sounds of air guns all fill the ocean with sound, reducing whales’ communication range and listening area, and likely increasing stress levels because of these reductions.  This is the “din” of chronic moderate human noise in the sea, and Kina’s ability would not help her cope with any of it.  We’re a long way from being able to rest easy about our sonic impacts in the oceans.

To end this rant with a bit of credit where due, here’s what may be the more important take-away from the Times article:

Peter Madsen, a professor of marine biology at Aarhus University in Denmark, said he applauded the Hawaiian team for its “elegant study” and the promise of innovative ways of “getting at some of the noise problems.” But he cautioned against letting the discovery slow global efforts to reduce the oceanic roar, which would aid the beleaguered sea mammals more directly.

Health Canada launches 2-yr, 2000-person study of wind farm health effects

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Health Canada, the country’s health department, is preparing to launch a study of health effects among residents near wind farms.  The study as currently planned will be based on interviews and physiological measurements of 2000 people living near wind farms of 8-12 turbines.  Each participant will fill out a self-reported health survey, and will be tested for stress hormones, blood pressure, and sleep patterns.  Study subjects will live from under 500 meters from turbines to over 5km.

The research design and methodology has just been made public, and is open for public comment until August 8.  Among the key methods outlined, with my initial thoughts in brackets:

  • Sleep patterns will be monitored using wrist-worn devices for seven consecutive nights. [Will this be long enough to capture sleep-disruption trends, if they exist?  It would be good to ask study participants who self-report sleep disruption whether the week chosen for testing was representative of their worst weeks, average weeks, or below-average weeks, in terms of sleep quality.  A pilot study will examine the usefulness of adding a sleep diary to the full study protocol; this should be encouraged as a way to assess sleep patterns over a longer period of time, ideally including seasonal differences.]
  • Sound levels will largely be modeled based on measured sound levels near the turbines, including sound into the infrasonic range; these models will be validated in the field at distances of up to 5km. [It would be good to know the full range of frequencies that will be modeled and measured.  In addition, medium- to long-term validation measurements in the field would be useful, in order to capture a better sense how often worst-case noise periods may occur; such events may be relatively rare or seasonal but be important elements in community response, especially stress responses.  Models to be utilized should be based on recent studies that have found lower frequency elements of wind turbine noise often attenuate at a lower rate than higher frequencies; this is especially important in considering any possible effects of audible low frequency sound at distances of a kilometer/half mile or more.)
  • Sampling out to 5km (3.1 miles) will allow researchers to generate a dose-response curve based on the sound levels of the turbines.  [5km is probably a decent distance to use for an effective control, in that turbines are nearly always inaudible at such a distance.  I would hope that the study design can assure that there are enough subjects at close range, especially within 1km (.6 miles) and 2km (1.25 mi). to be sure that any reported and measured health effects will be statistically significant.  While I appreciate the need to have statistical significance at all distances, “wasting” too many subjects at greater distances could make it more difficult to be sure of any effects found at the distances where they appear to be more common, and at which there is apt to be a greater range and complexity of responses.]
  • [While a dose-response relationship is a foundation of many health effects, there are many other factors that tend to make individuals more or less susceptible to whatever health stressor is being studied.  It would be helpful to include assessment of some of the factors that could be contributors to a health effect from wind farm noise, including noise sensitivity, pre-existing vestibular issues, and susceptibility to motion sickness, among others.]

Michigan PSC disbands wind farm noise work group that was poised to recommend 40dB limit

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This is somewhat old news, but a recent article brought it to my attention. The Michigan Public Service Commission’s Wind Working Group, an advisory committee, appointed a Wind and Health Technical Work Group in 2010 to look at siting standards; they were charged with making recommendations regarding physical safety and noise limits.  Dr. Jerry Punch, an audiologist and professor emeritus at Michigan State University, was chosen to chair the panel. Kenneth Rosenman a professor of epidemiology (occupational diseases) at MSU was co-chair.

Over the course of their first year of meeting and discussions, it became clear that Mark Clevey, a manager for Consumer Education and Renewable Energy programs with the State Energy Office, didn’t agree with the direction in which the panel seemed to be heading.  “He (Clevey) came to a few meetings and then stopped coming,” Punch said. “Later, we were contacted and told that they had reorganized and that the work group was no longer needed.”

Soon, Clevey was presenting the work of the Wind and Health group under his name; this March 2011 presentation is the final mention of the project in the records of the Wind Working Group, which has met three times since then. In that presentation, Cleavy stressed the role of community engagement to alleviate concerns, and posited that there is insufficient evidence to spur any changes in current noise standards, which stand at 55dB.

However, Punch, Rosenman, and one other member of the Technical Working Group released their own report, summarizing what had been the emerging recommendation of their group before it was disbanded.  The key recommended change in Michigan standards is that noise from wind turbines should be limited to 40db at night, as measured outside homes. It’s not entirely clear if they’re recommending a 40dB annual average, or a 40dB average over a number of 10-minute periods.  Their recommendations also include the option for wind developers to obtain waivers from homeowners, to allow sound levels higher than 40dB; but they recommend an absolute maximum of 55db, which is the current state noise limit for wind farms.

UPDATE, 7/22/12: A followup report from the same source as the above article details a bit more of the behind-the-scenes conversation among Michigan regulators.  This followup details an email sent by John Sarver, who had recently turned his State Energy Office job over to Clevey, written to Clevey and Julia Baldwin, who was moving to the Michigan PSC as Renewable Energy Section Manager.  Sarver advocated that the Technical Work Group be allowed to complete its process, but that they should be made aware that Clevey was not planning to make regulatory changes based on the report; he also encouraged them to delete their internal emails on the topic “because of the possibility of FOIA requests.” (And, indeed, it was a Freedom of Information Act request that revealed this email.)



Massachusetts towns address turbine noise issues

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A trio of towns in southeastern Massachusetts continue to address turbine noise issues in response to neighbor complaints about sleep disruption and health effects near small wind farms of three to four turbines each.  

In Falmouth, which was the first of the towns to have turbines begin operating close to homes, the affected neighbors have joined a committee charged with coming up with a set of options to present to the Selectmen, hopefully in time for the November town meeting.  

Across the bay in Fairhaven, where even more people live within a half mile or so of turbines that began operating this spring, the Board of Health has received over a hundred complaints, and asked the developer to submit a plan for how he might be able to reduce noise and flicker issues; the first response, received this week, was more focused on doubting the veracity of the complaints.  Sumul Shah, the developer, stressed that nearly two-thirds of the 132 complaints had come from either plaintiffs in the lawsuit against the town seeking to dismantle the turbines or others who had publicly voiced their opposition to the turbines before they were operational, suggesting that since some others seem to tolerate the noise, those complaining should be able to also.  Ed. note: Indeed, many nearby neighbors objected to the turbines as they were being permitted, based on the problems that had cropped up in nearby Falmouth.  The fact that some of these same people are now experiencing noise issues should not come as much of a surprise to anyone; about fifty of the complaints have come from people not involved in either effort to stop the turbines.

Board of Health member Barbara Acksen said she was appalled by Shah’s letter, saying “We were not at all pleased with the report. He should just be responding to the data and not casting aspersions on people who complain,” she said. “You can’t just say ‘Well, these people didn’t like the turbines before so their complaints don’t matter.'”  Shah says that he can’t consider mitigation options until it’s determined whether the turbines are out of compliance with state or local noise statutes; the state DEP will begin noise tests sometime in the coming month. it appears that this may become another in a series of projects in which a wind farm may operate largely or totally within its permitted noise criteria, while still causing widespread noise issues for neighbors.  This situations suggest that many noise standards may not be sufficient in communities used to peace and quiet, yet home to a moderate density of homes.

Meanwhile, in Kingston, residents continue to express dismay at turbines that began operating earlier this year.  Chris Dewitt said his heart aches at the impact these turbines have had on his family and his neighbors. He said he personally has been woken up early in the morning, around 3:30 a.m. one day and 4 a.m. the next, because of the noise of the turbines. “This is not sustainable,” he said. “Think about this decision in respect to the people.”

One of the more revealing comments I’ve seen lately about living near turbines was in a comment submitted to the paper that ran the Fairhaven story:

I live 2/3rds of a mile away from them. Not a day doesn’t go by I don’t hear them. Not 1. I say again 2/3rds of a mile away! How loud do they need to be for them to be heard at that distance – constantly? Most nights the noise isn’t loud enough to keep me awake. Sometimes it is. So it is my experience that the people who live much closer have a very very legitimate complaint. I can’t imagine living closer to them.

McCain, Reid succeed in quest to stop Grand Canyon overflight rules

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CanyonI guess the third time was the charm for John McCain in his relentless quest to undermine the National Park Service’s decades-long effort to slightly reduce aircraft overflight impacts in the Grand Canyon backcountry.  Since the NPS released its draft plan several months ago, McCain had crafted amendments to a couple of pieces of legislation in an effort to codify the status quo overflight rules; this week, it was inserted into the Transportation bill that was passed by the House and Senate and quickly signed by President Obama.  The Arizona and Nevada congressional delegations, including Harry Reid, had supported the effort to assure no changes to air tour operations (most air tours are based out of Las Vegas, allowing casino visitors a quick look at the canyon).

Despite the fact that the NPS draft would have allowed more annual tourist flights than have ever occurred, the air tour industry painted the plan as an economic death sentence.  The plan would have created some seasonal flight path restrictions, offering different areas of the park a bit more sonic space at different times of year, and, most substantially, would have kept air tours out of the sky for an hour after sunrise and an hour before sunset.  I have to wonder if the sunset restriction may have been the bitterest pill for the air tour operators to swallow, though it would have been a substantial boon for hikers and river rafters.  Given the relatively soft definition of quiet being attempted, to have a couple hours a day of soft light and no air traffic seemed to me to be the fairest solution.

The NPS plan would have aimed to let 70% of the park experience “substantial natural quiet,” which means no planes audible 75% of the time (i.e., planes can be audible one minute of four, or fifteen minutes per hour, hardly a pristine soundscape).  The McCain effort as passed will maintain the status quo of substantial natural quiet in half the park; the other half of the park has no limits on aircraft audibility.

See these links for earlier AEI coverage of the final NPS draft and subsequent legislative attempts to derail it.  Here’s initial news coverage of the final stealth success in derailing the process.