Over the past few months I have read with interest the ongoing editorial comments on the proposed Silcote Corners wind farm. I have had the opportunity to attend a few impromptu meetings with residents inside the project boundaries and outside. As well, I have participated in organized groups striving to create some cohesive resistance to the project.
What I have found particularly intriguing is the consistent and almost automatic dismissal of the health impacts for those colocated with the turbines. I have listened to people arbitrarily dismiss health issues as being psychosomatic or regurgitate the popular excuse of the lack of scientific evidence. With respect, I would suggest to those who support these notions that you have completely misunderstood the problem.
The fact that the Silcote project involves wind turbines really is inconsequential. The core issue would be the same if we were considering the placement of a new manufacturing plant, an industrial complex of some type, an airport or a multi-lane highway in this rural setting. The fundamental problem is environmental noise. Wind turbines are just the instrument.
In that context, if anyone suggests that we are lacking in scientific knowledge regarding the impact(s) of environmental noise on human health, I would offer the following. Every year there are international conferences held on the subject some of which specialize in certain types of environmental noise (i. e. low frequency noise). There are numerous journals published on the subject. These publications catalogue a continuously growing collection of peer reviewed scientific experiments and research studies from subject matter experts, medical professionals and academics on the human impact of environmental noise. There are periodicals for medical specialists like audiologists that help facilitate an understanding of symptoms and treatment for those affected by exposure to environmental noise. With the quality and depth of these resources we are exceedingly well equipped with intelligence to act in situations where humans are at risk, regardless of the source of the noise. In turn, there is a well established regulatory environment intended to minimize the risk of exposure.
To illustrate, the province of Ontario has noise restrictions that must be met by a developer of any of the above mentioned projects (including industrial wind farms).Those requirements are summarized in a publication called Sound Levels for Stationary Sources NPC-232. In that publication it stipulates that no installation shall exceed a maximum noise level (i. e volume) of 40 decibels during the evening and 45 DB during the day.
The word “maximum” is slightly misleading since it is not an absolute maximum but rather a “one-hour equivalent” or average. However, we will set that aside.
What science tells us about the loudness of 40-45 DB is that it is equivalent to the noise level in a library. That statement is often touted by wind farm proponents and it is absolutely true. Unfortunately, by itself, that fact is also totally irrelevant. The ambient noise level in rural environments like Silcote Corners is from 25-30 DB, since it is not influenced by other background noises of traffic, industry etc. So the question becomes, how disruptive is a noise of 40-45 DB from an industrial complex (like the wind farm) when it is located in a natural environment with an ambient noise level of 25-30 DB (or 15-20 DB less)? Science informs us that when the volume of any noise is increased by 3 DB that noise becomes “noticeable.” Increases of 5 DB are loud enough to be considered annoying. Increases of 10 DB represent a doubling of volume to the human ear. Therefore, 40 DB is twice as loud as 30 DB to humans. That size of increase changes a sound from noticeable to intolerable. Consequently, if we place our “library” in an enviro n m e nt where the natural volume is only half as loud, the “library” will be the noisiest thing in the neighbourhood.
What we also know from science is the fact that human hearing is very subjective. What some find annoying doesn’t bother others. Therefore, doubling the level of ambient noise in an environment like Silcote won’t be an issue to everyone. However, to assume that it won’t be dangerous to anyone would be naive. Those individuals who find the noise increase intolerable have the greatest risk of negative health impacts. Science is clear regarding the health implic at i o n s citing increased headaches, possible nausea and sleep deprivation as the most common symptoms. Prolonged exposure to these conditions increases stress and the risk of depression, anxiety and cardio vascular disease. The sad reality is that, if the noise is permanent, the cure is to move away.
As an interesting aside, the Vestas wind turbines destined for Silcote Corners, have a sound power rating between 95 DB and 103 DB per turbine depending on wind velocity. When they are clustered together there is an incremental increase in the sound power as each turbine is added. As a result, in accordance with the Green Energy Act, to meet NPC-232 requirements wind turbines are set back 550 metres from a receptor. The fact that the 95+DB noise will dissipate to a level of 40-45 DB at a distance of 550 metres is only based on a mathematical (albeit scientific) formula.
There is no requirement for measurement, validation or monitoring unless there are noise complaints after the fact. Obviously however, the closer to the turbine you are the louder the noise. So to those participants who have relinquished their rights to setbacks and choose to utilize their property as a site for multiple turbines, all the best of luck. In Germany, if a wind farm is built in an environment characterized by a 35 DB ambient noise level the setback from any receptor is 1.5 kilometres.
Unfortunately, all of this only focuses on part of the issue of environmental noise. That is, that part of the noise spectrum that humans can hear. The other part is the noise that is less audible or completely inaudible such as low frequency noise and infrasound. What we know from scientific research is that low frequenc y noise and infrasound behaves differently from higher frequency audible sounds in that it does not decrease over distances. That partially explains why elephants and whales use low frequency noise to commun i c at e over great distances through the ground and oceans.
We also understand that solid structures like houses can actually amplify the sound through vibration. That means it won’t be blocked out by going inside and shutting doors and windows. Only a portion of low frequency noise is audible. Infrasound, defined as less than 20 Hz, is below the hearing threshold of humans. It will only be felt through inner ears and body sensations. Thus the volume in decibels is irrelevant because you don’t hear it. Increased volumes of infrasound will however, speed the body reaction.
What we know from science is that every organ in the human body can resonate or vibrate from exposure to low frequency noise. As examples; low frequency noise of 50 Hz (hertz) stimulates vibration in the chest cavity; at 30 Hz abdominal organs can do the same; at 17 Hz vision can be blurred due to vibration of optic nerves. The science concerning the risk of exposure for humans is explicit. It has been acquired from years of occupational studies, military experiments and the life experience of individuals in neighbourhoods co-located with industrial factories.
The emission of low frequency noise from wind turbines is also well recognized. Over the course of the decade from 1980-1990 NASA researched this specific problem and their efforts led to a fundamental redesign of turbines.
Low frequency noise emissions have improved but have not been eliminated. Unfortunately, with current industry standards on wind turbines, manufacturers are not required to specify low frequency noise emissions. Moreover, the standards that are used are well known to understate the low frequency component. The Japanese, at the end of 2009, curtailed installations of wind farms and initiated a four-year epidemiological study on people living near turbines to understand the issue of cell damage in the human body due low frequency noise exposure.
To perpetuate the debate on health issues and wind turbines at best is unproductive and at worst is dangerous for the future health of all of those in the Silcote area. Those who dismiss the concern as illegitimate only demonstrate how hopelessly uninformed they are.
We have the science, the expertise and the intelligence to tackle the issue head on if we define it in the appropriate framework. It is not about a wind turbine. It’s about protecting the health of the people in our community against the negative impact of environmental noise whether they can hear it or not and irrespective of the source.
We need municipal politicians to use the knowledge we have, take the next steps beyond a moratorium and construct bylaws to get the sources of environmental noise away from inhabitants. We do not need more health surveys to add to the portfolio of examples of human victims suffering from what science has already explained would happen.
We need to take that expertise and add it to a collective political voice that demonstrates we are prepared to take control of the development in our community.
Dan Reid, Annan