Disley v Mount Emerald Wind Farm Pty Ltd & Anor (No 2) [2022] QSC 54
SUPREME COURT OF QUEENSLAND
CITATION: Disley v Mount Emerald Wind Farm Pty Ltd & Anor (No 2)
[2022] QSC 54
PARTIES: Jennifer Disley
(plaintiff)
v
Mount Emerald Wind Farm Pty Ltd
(first defendant)
and
Marshall Day Acoustics Pty Ltd
(second defendant)
FILE NO/S: SC No 683 of 2020
DIVISION: Trial
PROCEEDING: Application
ORIGINATING
COURT:
Supreme Court of Queensland
DELIVERED ON: 8 April 2022
DELIVERED AT: Cairns
HEARING DATE: 23 March 2022
JUDGE: Henry J
ORDERS: 1. The plaintiff serve further revised, stand alone, expert
reports of Dr Robert Thorne and Mr Steven Cooper
that address separate issues in the proceeding by 4pm 6
May 2022 or such later date as the defendants may in
the meantime consent to in writing.
2. Paragraph 9 of the consent order for ADR dated 3
December 2021 is varied so as to delete the words “four
months” and replace them with the words “eight
months”.
3. The plaintiff pay the defendants’ costs of and incidental
to the hearing of 23 March 2022.
4. Liberty to apply on the giving of two clear business days
notice in writing.
CATCHWORDS: PROCEDURE – CIVIL PROCEEDINGS IN STATE AND
TERRITORY COURTS – PROCEDURAL ASPECTS OF
EVIDENCE – EXPERT REPORTS AND EXPERT
EVIDENCE – OTHER MATTERS – where the defendants
sought orders precluding the plaintiff from calling more than
one expert witness in respect of particular issues – where
orders were made that the plaintiff was to elect between one of
two expert reports or revise both reports so that each address
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different topics – where two new reports were provided to the
defendants – where the defendants complained the two reports
did not address separate issues – whether the two reports
address different topics – whether discretion should be
exercised to order amendment of the two reports
Uniform Civil Procedure Rules 1999 (Qld) r 367(3)(e)
COUNSEL: M Jonsson QC for the plaintiff
J Horton QC and E Hoiberg for the first defendant
M Doyle for the second defendant
SOLICITORS: GLT Legal for the plaintiff
Allens for the first defendant
Wotton + Kearney for the second defendant
[1] Applications filed in October 2021 relevantly sought orders precluding the plaintiff
from calling more than one expert witness in respect of particular issues. The
applications occurred against a background where the plaintiff had sought no order
from the court regarding expert evidence before procuring two lengthy expert reports
which it had served upon the defendants.
[2] The two expert reports both spoke of assessments based on standardised audio
measures and assessments based on noise perception appraisals. In short, their reports
in various respects spoke to the same issues, contrary to the general principle that,
without compromising the interests of justice, evidence on a particular issue should
be given by a single expert.
[3] On 29 October 2021 I concluded that the two expert reports addressed broadly the
same topics and the plaintiff should not be permitted to adduce both reports as they
existed at the time, at trial.1 My orders included:
“Pursuant to Rule 367(3)(e) of the UCPR, the plaintiff must either:
(a) elect as between expert witnesses, Robert Thorne and Steven
Cooper, which expert it intends to rely upon at trial, notifying the
defendants of its election by no later than Friday 12 November
2021; or
(b) in the event it prefers to have those experts provide evidence
addressing separate issues, notify the defendants of its intention to
do so by no later than Friday 12 November 2021.”
[4] By letter dated 12 November 2021 the plaintiff notified the defendants of their
intention to continue to rely upon both experts but with them addressing separate
issues.
[5] When the new versions of the two experts’ reports were provided by the plaintiff to
the defendants, the defendants complained the reports did not in fact address separate
issues in the proceedings. The plaintiff disagreed. The dispute was eventually
1 Disley v Mount Emerald Wind Farm Pty Ltd Unreported Cairns Supreme Court Henry J 29 October
2021.
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flagged as being the subject of argument to be resolved by me when it returned before
me for review and further directions on 11 March 2022. I listed the argument for
hearing on 23 March, at which the defendants sought an order that the plaintiff serve
further revised expert reports of Dr Robert Thorne and Mr Steven Cooper that address
separate issues in the proceeding.
[6] It may be observed at once that the reports purportedly served in compliance with my
order were deficient because each author referred to the content of their former
reports.2 Their new reports should have been comprehensible based on their content
alone and not contained references to their earlier reports. The inclusion of such
references would necessarily mean when any expert or experts engaged by the
defendants reviewed those reports, that they would also need to review the earlier
problematic reports – a recipe for unnecessary cost and confusion. Even before
getting to the substantive issues in the dispute before me I conclude the plaintiff will,
at the very least, need to procure reports from their two experts which are stand-alone
reports and do not refer to their earlier reports.
[7] In considering whether the new reports (hereinafter simply referred to as the reports)
address separate or the same issues in the proceeding it is helpful to first review the
issues in the proceeding which could sensibly be the subject of expert evidence from
Dr Thorne and Mr Cooper.
[8] Dr Thorne holds a Doctorate in health science, for assessing intrusive noise and low
amplitude sound, and holds a diploma in acoustics and noise control. His work in,
what his curriculum vitae describes as, “the psycho acoustics of wind turbine noise”
focusses upon the subjective impact of low-frequency noise and inaudible audio
signals. Mr Cooper holds a Bachelor of Science (engineering) degree and a Master
of Science (architecture) degree in acoustics. His expertise of relevance to wind farm
noise lies in the objective assessment of a wind farm’s acoustic signature, including
within the infrasound region of the audio spectrum.
[9] The claim of the plaintiff, Ms Disley, seeks various relief including declarations,
restraining orders and damages deriving from her complaints about the effects of
noise from a wind farm which was constructed south of her rural property at
Walkamin, a rural district on the Atherton Tablelands between Mareeba and Atherton.
The Disley property houses Ms Disley’s home, as well as two houses, a cabin, a
cottage and a flat, which are allegedly used from time to time to provide worker
accommodation.
[10] The wind farm is a wind-powered electricity generation facility on which there are
53 wind towers and turbines. It is allegedly located about 1.87 kilometres from the
residential structures on Ms Disley’s property. The wind farm is said to be operated
by the first defendant (‘Mount Emerald’) pursuant to a development permit issued on
24 April 2015 and amended on 18 December 2015, and allegedly further amended on
31 January 2017 and 14 March 2018. The permit is said to have been approved by
the Queensland Minister for Infrastructure.
2 Dr Thorne’s report was marked exhibit 1 and Mr Cooper’s report exhibit 2 in the hearing. Mr Cooper’s
report contained distracting tracked changes and a version without such tracking was provided at my
direction. It has become court file document 36.
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[11] In summary, Ms Disley alleges Mount Emerald’s liability to her is for the nuisance
allegedly occasioned by the operation of the wind farm generating excessive noise
and vibration which, in turn, causes sleep disturbance and deprivation and other
discomforts such as earache, tinnitus, headache, accelerated heart rate and muscle
cramps.
[12] The statement of claim uses the acronym ILFN to refer to audible low-frequency
noise below 250Hz and subaudible air pressure fluctuations called low-frequency
noise or infrasound. It is alleged the noise generated by the wind farm has sound
energy, primarily comprising ILFN, which causes vibration to buildings and the
aforementioned impact on persons. This is allegedly not accounted for in the
conditions of the development permit or planning controls or applicable noise
standards because they do not require measurement or control of ILFN.
[13] It is alleged the noise generated by the wind farm has special audible characteristics
which increase and aggravate the annoyance and discomfort allegedly suffered.
Those characteristics are said to be the ILFN as well as tonality (the perceptible pitch
or tone of the noise), impulsiveness (noise containing impulse components with
pressure peaks) and amplitude modulation (often described as thumping or rumbling).
[14] It is also alleged (apparently as evidence inferentially supporting the excessiveness
of the noise and the unreasonableness of its interference with use and enjoyment of
Ms Disley’s property) that the noise periodically exceeds the daytime and night-time
noise limits of the development permit’s outdoor noise limits in schedule 1 of its
conditions of approval, described in the statement of claim as operational noise
requirements. Another alleged basis of its alleged breach of the operational noise
requirements is that, because of the aforementioned special audible characteristics,
so-called noise level penalties are to be applied to the measured operational noise
levels with the consequence that the wind farm is allegedly in persistent breach of the
operational noise requirements at all times during its operation.
[15] Ms Disley alleges the second defendant, Marshall Day Acoustics Pty Ltd (‘Marshall
Day Acoustics’) prepared five documents for Mount Emerald, predicting the impact
of the wind farm. The extent and context of Mount Emerald’s reliance on those so-
called MDA noise predictions is in dispute. In any event, Ms Disley alleges Marshall
Day Acoustics is also liable for the alleged nuisance of Mount Emerald because the
MDA noise predictions were relied upon in securing the development permit and
were thus allegedly causative of the nuisance.
[16] In addition, it appears to be alleged that Marshall Day Acoustics provided a defective
compliance report on 17 February 2020 which caused Mount Emerald to be able to
continue to operate and continue to cause the alleged nuisance. The compliance
report is alleged to be defective because:
(a) Marshall Day Acoustics did not investigate, quantify or report on the
aforementioned special audible characteristics;
(b) Marshall Day Acoustics excluded relevant noise data from the analysis on
which the compliance report was premised; and
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(c) the compliance report included and relied upon wind speed data from a wind
monitoring tower which had been decommissioned and could not have provided
relevant wind speed data thereafter.
[17] Ms Disley also pleads cases against Marshall Day Acoustics in negligence, negligent
misstatement and misleading and deceptive conduct. Its pleading of those various
foundations for liability relies upon complaints about the MDA noise predictions, the
advices Marshall Day Acoustics provided which were used to secure amendments to
the development permit and its compliance report.
[18] In combination, the complaints in relation to MDA’s noise predictions are that they:
(a) failed to predict the alleged periodic exceeding of Mount Emerald’s operational
noise requirements;
(b) failed to predict the above alleged persistent breach of Mount Emerald’s
operational noise requirements when noise level penalties are applied because
of special audible characteristics;
(c) failed to consider the special audible characteristics which would be generated;
(d) failed to identify the impact the true character of the noise would have upon the
plaintiff and other occupants, particularly in respect of sleep disturbance at
night;
(e) failed to assess the existing noise environment including by correlating noise
levels to different wind speeds and directions and to daytime and night-time;
(f) falsely asserted that wind, interacting with the natural environment, masks wind
turbine noise;
(g) falsely asserted that wind turbines do not generate significant levels of low-
frequency noise or infrasound at all;
(h) falsely asserted that a dB(A) noise weighting measures the true character of
noise generated by the wind farm.
[19] In relation to Marshall Day Acoustics’ subsequent advices, Ms Disley’s complaint is
that they were used to amend the noise conditions of the permit by removing
conditions 5 and amending condition 6, which originally required satisfaction of a C-
weighted (low-frequency) noise level outdoors. This allegedly had the consequence
that all protection and constraint with respect to low-frequency noise was removed.
[20] As to Marshall Day Acoustics’ compliance report, Ms Disley complains it failed to
address and report on special audible characteristics and excluded relevant noise data.
[21] This brief review of Ms Disley’s pleaded case exposes a variety of issues, some
recurring, some more major than others, which might potentially attract expert
evidence from experts such as Dr Thorne or Mr Cooper. One potential way of
articulating the more obvious of those issues might be:
(1) Does the noise generated by the wind farm have sound energy, primarily
comprising ILFN (ie. audible low-frequency noise below 250Hz and
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subaudible air pressure fluctuations called low-frequency noise or infrasound)
and, if so, is it of such an extent as to cause vibration to buildings and sleep
disturbance and other discomfort to residents of Ms Disley’s property?
(2) Does the noise generated by the wind farm have special audible characteristics
and, if so, are they of such an extent as to increase and aggravate the effects
mentioned in (1) above?
(3) Does the noise generated by the wind farm periodically exceed the daytime
and night-time noise limits of its operational noise requirements (ie. the
development permit’s outdoor noise limits in schedule 1 of its conditions of
approval)?
(4) Should the extent of any special audible characteristics of the noise generated
by the windfarm cause noise level penalties to be applied and, if so, would that
result in the noise generated by the wind farm persistently exceeding the
daytime and night-time noise limits of its operational noise requirements?
(5) Should the MDA noise predictions (ie the reports of Marshall Day acoustics)
have identified and allowed for ILFN and special audible characteristics as
part of the noise generated by the wind farm and, if so, did they adequately do
so?
(6) Should the MDA noise predictions have assessed the existing noise by
correlating noise levels to different wind speeds and directions and to daytime
and night-time and, if so, did they do so?
(7) Does wind interacting with the natural environment mask wind turbine noise
and, if so, to what extent is that effect applicable here?
(8) Does a dB(A) noise weighting measure the true character of noise generated
by the wind farm?
(9) Did the removal of development permit conditions 5 and amending condition
6 remove all protection and constraint with respect to low-frequency noise?
(10) Did the Marshall Day Acoustics compliance report adequately address the
impact of special audible characteristics?
(11) Did the Marshall Day Acoustics compliance report fail to have regard to
relevant data?
[22] To remove doubt, the above list is only illustrative. I do not intend it to be regarded
as an exhaustive list, indeed it does not draw upon the content of the defences or
replies.
[23] In preserving to Ms Disley the choice of forging ahead using both experts, as long as
they addressed separate issues, I expressly refrained from dictating what the various
issues to be addressed by singular expressions of expert opinion should be. To have
done so at that stage would have involved an inappropriate degree of interference
with the forensic choice of a party still considering the content of evidence to be
adduced. I expected however that her legal representatives would distil the many
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issues raised by her pleaded case down to a practical list of factual issues in the
proceeding to be separately addressed in the way I illustratively did in the preceding
paragraph. Such a list, with an endorsement against each issue as to which expert is
assigned to address it, would mitigate against duplication of expert evidence on the
same issue, not least because both experts would see the same list of questions and
know what their respective assigned issues are.
[24] In giving notice of the intention to elect to have their two experts address separate
issues in the proceedings by their letter of 12 November 2021 to the defendants, Ms
Disley’s solicitor said:
“Please be notified that the plaintiff prefers to rely on both her expert
witnesses, Robert Thorne and Steven Cooper, at trial. They will
provide evidence addressing separate issues, viz:
Robert Thorne
• Objective noise levels measured at the plaintiff’s home
between October-November 2019;
• Plaintiff’s subjective experience of noise including impact on
plaintiff’s amenity;
• Mitigation of noise at plaintiff’s home.
Steven Cooper
• MDA noise predictions from Mount Emerald Wind Farm;
• MDA post construction compliance reports for Mount
Emerald Wind Farm.”
[25] Such brevity in attempting to identify separate issues to be addressed would be
admirable if it were sufficiently clear to mitigate against duplication of expert
evidence on the same issue. It was not, as examples highlighted by counsel for the
second defendant show. Those examples were that, while Dr Thorne was supposed
to deal with objective noise levels measured at the plaintiff’s home between October-
November 2019, Mr Cooper’s report not only refers to monitoring which he
conducted of such noise levels but also includes elements of analysis by him of the
levels he recorded. Similarly, Dr Thorne was allocated the topic of the plaintiff’s
subjective experience of noise including impact on the plaintiff’s amenity, yet Mr
Cooper’s report recounts discussions with the plaintiff about that very topic, as well
as references to the plaintiff’s diary of impacts and analysis of a pattern of disturbance
correlated to the wind farm’s power output. Similarly, while Mr Cooper’s issues were
supposedly confined to the MDA noise predictions and the compliance reports, they
are each matters to which Dr Thorne’s report still makes some reference.
[26] The overlap in issues canvassed in both experts’ reports was also addressed by the
first defendant’s counsel in an appendix to their outline of submissions at the hearing.
Counsel for the plaintiff purported to answer those complaints, in part by contending
the issues identified were conclusions. The plaintiff’s counsel emphasised that the
issues to be addressed separately were necessarily issues of fact. That is correct, for
it is facts and opinion as to a state of fact, which expert evidence addresses. That
said, identifying issues as questions of fact will necessarily invite expressions of fact
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which are themselves conclusions (the expert opinion) based on other facts (the
factual foundation for the opinion). Sometimes those other facts include opinion in
turn founded on another sub-stratum of facts. Much of course depends on the level
of precision or abstraction with which the issue in question is stated.
[27] Allowing for some reasonable divergence of views as to how the issues ought be
articulated, the overlaps identified in the aforementioned appendix are not all overlaps
of actual issues, but some obviously are. Furthermore, I note even by reference to my
illustrative list of 11 issues at [21] above that there is material overlap in respect of
issues (5)3 and (6)4.
[28] Such overlaps are scarcely surprising in light of the fact that each expert was given a
much longer list of issues in question format to address than the short list of issues
appearing in the letter of 12 November 2021. Each of the lists of questions was
different. As a result, each expert might have been uninformed as to what issues the
other was addressing and thus uninformed about the degree to which their evidence
in response might risk encroaching upon an issue being responded to by the other.
Much more problematically, the superficially different lists of questions for each
expert contain various questions which are connected with the same issues.
[29] For example, Dr Thorne was asked whether noise emissions from the wind farm had
any special audible characteristics and, if so, what impact they had on the measured
ambient sound levels received at the plaintiff’s home. Mr Cooper was asked whether
the second defendant considered or assessed any potential for special audible
characteristics to impact noise received at the plaintiff’s property. These questions
are cosmetically different, but they went to the same topic with the inevitable results
that both experts expressed the view that the second defendant did not assess special
audible characteristics at the plaintiff’s property.
[30] The lists of questions posed go to issues which are not all recognisable as issues of
fact arising from the pleadings. This presents a particularly confusing challenge for
the defendants in determining what approach they should take to the engaging and
instructing of experts. Are they to ask their experts to write reports by reference to
the pleaded issues to which an expert’s expertise is relevant or to the plaintiff’s lists
of mixed questions posed to their experts? I would have thought it was implicit in
the court requiring that a separate issue be addressed by only one expert from the
plaintiff’s side that the division and articulation of separate issues would bear some
recognisable correlation to the pleaded issues and the respective areas of expertise of
the experts. To remove doubt, the division and articulation of separate issues should
have those qualities.
[31] One aspect of some of the overlaps and likely a cause of some of the others is reliance
by one of the experts upon raw data gathered and opined upon by one of the other
experts. Such raw data is real evidence. If it is relevant to the remit of one of the
experts to have regard to and analyse such data, then it would be permissible to do so
notwithstanding that it happens to be data gathered by another expert. The operative
distinction is the distinction between real evidence, namely raw data gathered, and
opinion evidence, namely the analysis of and conclusions to be drawn from that data.
There can be no sensible objection to an expert who is expressing an expert opinion
3 Compare for example Thorne [11.7] and Cooper [59].
4 Compare for example Thorne [5.6], [12.7] and Cooper [28].
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on data gathered by another expert incorporating the other expert’s data as an
appendix to their own stand-alone report.5 However, it is only that expert who should
be advancing an opinion as to what that data means in respect of the applicable issue.
If this distinction is honoured it will help avoid material overlaps.
[32] I am conscious that the plaintiff will have expended a considerable amount of money
in procuring the initial expert reports and, more recently, in procuring the new reports
in attempted compliance with my order of 29 October 2021. Yet it was the plaintiff’s
choice to have, without recourse to the court, procured reports in the first place which
overlapped to a significant degree. It was likewise the plaintiff’s choice to opt to
forge on with two expert reports procured by the approach described above.
Regrettably, that approach has given rise to reports which do not comply with my
order.
[33] There was no indication in the course of argument that, if unsuccessful in resisting
the defendants’ application, the plaintiff intends to do other than continue to attempt
to adduce expert evidence from both Dr Thorne and Mr Cooper. That being so, the
appropriate order is that the plaintiff serve further revised expert reports of Dr Thorne
and Mr Cooper that address separate issues in the proceeding by 4pm 6 May 2022.
[34] Consistently with the approach discussed in my reasons of 29 October 2021, I again
refrain from purporting to direct what the various issues to be addressed by singular
expressions of expert opinion should be. However, in the event that the plaintiff
wishes to reduce the risk of a further failure of compliance with my order she may do
so by requesting the Court’s directions as to whether a proposed list of issues in the
proceeding to be separately addressed by their experts is appropriate. I will include
a liberty to apply clause which will allow that to occur.
[35] In the event the plaintiff wishes to pursue that course she should not put the
defendants to the costs of such an appearance without first consulting the defendants
to ascertain whether they agree that the list proposed to be placed before me is
appropriate. Such consultation should prompt sensible discussion and hopefully
agreement, dispensing with the need to come back before the Court for further
argument. Such discussion and agreement would be strongly in the interests of the
defendants too for they will have to grapple sooner or later with the same task. The
clearer both sides are as to the appropriate division of separate issues for expert
evidence in the case the easier and less expensive it will be for them to co-ordinate
the procuring of expert evidence in the case. Time invested now in all sides’ lawyers
meeting to discuss and resolve an appropriate list of issues to be addressed by expert
evidence will inevitably be to the very substantial benefit of all sides’ clients in the
long run.
[36] To remove doubt as to the nature of the hint just given,6 were any party to seek a
direction that the parties so meet, I would give it. In anticipation that such a meeting
may delay compliance with the date contemplated by my orders I will provide for
variation of that date by consent.
[37] Costs should follow the event. I note the defendants also sought costs for the
directions hearing at which this dispute was first mentioned before me. The costs of
5 The content of the appendix may later need to be proved by calling its creator at trial, if it is in issue.
6 A hint rather than a direction because the idea was not raised in argument.
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that appearance at a directions hearing in the course of the Court’s management of
the case ought be costs in the cause. The costs order in favour of the defendants
should only be in respect of the costs of and incidental to the substantive hearing of
the argument.
[38] My orders are:
1. The plaintiff serve further revised, stand alone, expert reports of Dr Robert
Thorne and Mr Steven Cooper that address separate issues in the proceeding by
4pm 6 May 2022 or such later date as the defendants may in the meantime
consent to in writing.
2. Paragraph 9 of the consent order for ADR dated 3 December 2021 is varied so
as to delete the words “four months” and replace them with the words “eight
months”.
3. The plaintiff will pay the defendants’ costs of and incidental to the hearing of
23 March 2022.
4. Liberty to apply on the giving of two clear business days notice in writing.
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Official source: https://www.sclqld.org.au/caselaw/QSC/2022/054