Day 43 of Ostrander Point — Reply testimony of Dr. John Harrison and Dr. Robert McMurtry
[After 43 days of hearings, the evidence is complete except for final written submissions, and oral reply to these submissions, which will be heard in Toronto on June 21, 2013 at 09:30 (a teleconference link will be available). The decision of the Tribunal will be released no later than July 10, 2013.]
Report on June 7th ERT Hearing on Human Health Appeal
by Henri Garand, Chair, APPEC
The Environmental Review Tribunal heard the reply evidence of two APPEC expert witnesses: Dr. John Harrison and Dr. Robert McMurtry.
Qualifying of Dr. John Harrison
John Harrison, Ph.D., Queen’s University professor emeritus of physics, has been studying wind turbine noise since 2006 when a wind project was proposed for Amherst Island, on which he resides. Subsequently, he made presentations to the Ministry of Environment (MOE) and delivered papers at wind energy conferences and the Canadian Acoustics Association.
Both Gilead Power lawyer Bryn Gray and MOE lawyer Sylvia Davis objected to Dr. Harrison on the basis that he was not an expert in acoustics, his position as vice president of the Association to Protect Amherst Island showed bias, and his evidence went beyond matters raised in earlier testimony.
After a morning of debate the ERT panel qualified Dr. Harrison as an “expert physicist” and limited the scope of his evidence.
Examination of Dr. Harrison
Dr. Harrison questioned the noise levels defended by witnesses Shant Dakouzian, Denton Miller and Dr. Werner Richarz:
- Sound power level specifications are not accurate for the operational range of atmospheric conditions. A large wind speed gradient enhances amplitude modulation by 5-8 dBA and in extreme cases by up to 15 dBA.
- A conservative ground parameter is 0. 5, not 0.7, because it balances hard and soft surfaces.
- Aerodynamic noise in wind turbines is generated predominantly by the blades and turbulent inflow noise. Rotation modulates the amplitude of the turbine noise at the blade passage frequency. Typically the amplitude modulation is 3 to 5 dBA, with examples in the range 8 to 10 dBA.
- The MOE’s 2008 Noise Regulations do not acknowledge turbulent inflow noise.
- Despite improvement in the MOE’s noise guidelines and measurements, variations are still possible of 1-5 dBA.
Cross-Examination of Dr. Harrison
Ms. Davis asked a clarifying question on ground parameter. Mr. Gray had no questions.
Examination of Dr. Robert McMurtry
Dr. McMurtry began by acknowledging six areas of partial agreement with the expert witnesses supporting Gilead’s and the MOE’s position:
- Symptoms are commonplace in the general population. However, qualitative analysis is essential because there is qualitative complexity to most symptoms such as sleep disturbance, tinnitus, dizziness, nausea, cognitive difficulty, mood disturbance.
- Economic Impact. Hosts of wind farms are less likely to complain, but being paid to do anything is likely to change behavior, including risk taking.
- Lack of linear relationship between dBA exposure and complaints. However, dBA is an inadequate measure to capture all the qualities of IWT noise or the turbine signature noise. Special Acoustic Characteristics include ILFN content, intermittency, amplitude modulation, lack of night-time abatement, origin in quiet rural areas, etc.
- Bias exists among critics of the wind industry. However, examples may also be cited among wind energy supporters.
- Adverse health effects secondary to living in the environs of wind turbines (AHE/IWT) are not part of mainstream medicine. However, noise itself is long recognized as a health risk and is generally regulated.
- Insufficient Evidence. There is insufficient evidence about the precise mechanism of harm to humans but not that adverse effects are occurring.
Dr. McMurtry then explained six domains where lack of agreement is evident:
- “Toward a Case Definition of Adverse Health Effects in the Environs of Industrial Wind Turbines” (AHE/IWT). The task of his case definition is to weight the unique elements of AHE/IWT to distinguish the clinical disorder from competing explanations. The common themes found in the reports of AHE are reflected in the first- and second-order criteria. There are few, if any, alternate explanations for the first- and second-order criteria. The third-order criteria serve the purpose of capturing the most commonly reported symptoms. Taken alone the third-order criteria are unhelpful in establishing a diagnosis.
- Multiplicity of Symptoms. Symptom counts are not useful for making a diagnosis or ruling it out. Some complaints may be true and others inaccurate. In general, counting symptoms is not a useful exercise and ought not to be the focus of research.
- Ottawa Charter vs. World Health Organization (WHO). The WHO has not set aside its original definition of health but has appropriately emphasized the importance of health promotion.
- Plausibility of Biological Mechanism for AHE/IWT. In 2010 the MOE’s commissioned report by HGC Engineering concluded: The audible sound from wind turbines, at the levels experienced at typical receptor distances in Ontario, is expected to result in a non-trivial percentage of persons being highly annoyed. Research has shown that annoyance associated with sound from wind turbines can be expected to contribute to stress-related impacts in some persons. This finding appears to provide a plausible biological mechanism for complaints of persons being “highly annoyed,” which has been found by Eja Pedersen and others to produce stress, psychological distress, difficulty initiating sleep, and sleep disruption. In 2011, a WHO study of Occupational Noise in Europe concluded that “a high level of annoyance caused by environmental noise should be considered as one of the environmental health burdens.”
- Modelling and Monitoring. There is no reason to be confident in the modeling of IWT noise exposure. What is known is that at the current setbacks people are becoming seriously ill. The monitoring protocol does not include any health evaluation of exposed persons. Instead, only measurement of noise emissions is undertaken.
- Age-related Changes accounting for complaints. The expert medical witnesses for the proponents have pointed out that many complaints may be related to the process of aging. But children are also reported as adversely affected with ear pain, disrupted sleep, and regression in development.
Finally, Dr. McMurtry reviewed the Bradford-Hill criteria for causation and explained their relevance to current and needed research. He said the criteria indicated a strong basis for the causal relationship between wind turbines and the reported adverse health effects.
Cross-examination of Dr. McMurtry
Gilead Power Lawyer Darrel Cruz asked Dr. McMurtry to consider a number of documents with conflicting evidence and dissenting opinions. In each instance Dr. McMurtry challenged the inferences and pointed out their limitations.
Ms. Davis presented a 2013 revision of an Ontario Agency for Public Health Protection (OAPHP) publication, and she called Dr. McMurtry’s attention to a table citing 40-45 dBA as the noise threshold for sleep annoyance.
Re-examination of Dr. McMurtry
Referring to the same OAPHP publication, Mr. Gillespie directed Dr. McMurtry to another section which stated that sleep annoyance from wind turbines has been reported below 40 dBA.
Co-chairs Robert Wright and Heather Gibbs confirmed that final written submissions from all parties are due June 10 and oral reply is scheduled in Toronto on June 21, starting at 9:30 a.m. Teleconferencing will be available.