Noise Impact Assessment Dalveen Wind Farm Dalveen, QLD

Transcription

1 Dalveen Wind Farm Dalveen, QLD Document No. SP0372-0, Revision 1 Prepared for: Muirlawn Pty Ltd PO Box 5816 West End QLD May 2013

2 DOCUMENT CONTROL PAGE SAVERY & ASSOCIATES PTY LTD Suite 4, The Gap Village 1000 Waterworks Road The Gap QLD 4061 PO Box 265, The Gap QLD 4061 Telephone: (07) Facsimile: (07) REVISION HISTORY Revision No Issue Date Revision Description Checked By Issued By 0 20/05/13 Draft DB MT 1 20/05/13 Final DB MT DISTRIBUTION RECORD Copy No(s) Rev No Destination 1 0 Muirlawn Pty Ltd 2 0 Savery & Associates File 1 1 Muirlawn Pty Ltd 2 1 Savery & Associates File This report has been prepared by Savery & Associates Pty Ltd for Savery s clients or Savery s own internal purpose. It is based on site inspections and information provided by sources external to Savery. In the circumstances neither Savery nor any of its directors or employees gives any warranty in relation to the accuracy or reliability of any information contained in the report. Savery disclaims all liability to any party (including any direct or consequential loss or damage or loss of profits) in respect of or in consequence of anything done or omitted to be done by any party in reliance, whether in whole or in part, upon any information contained in this report. Any party who chooses to rely in any way upon the contents of this report does so at their own risk. This report is confidential and may contain legally privileged information and/or copyright material of Savery & Associates Pty Ltd or third parties. You should only distribute or commercialise this report if you are authorised to do so by Savery & Associates Pty Ltd. SP0372.R1 Dalveen Wind Farm - Noise Assessment.docx ii Revision 1-20 May 2013

3 Executive Summary This report has been prepared by Savery & Associates Pty Ltd for Muirlawn Pty Ltd to prepare an acoustic assessment of the noise impacts associated with the proposed Dalveen Wind Farm in Queensland. The purpose of the proposed works is to assess the proposed wind farm for compliance with the relevant noise limits at sensitive receptors in accordance with Council s requirements in their request for information dated 21 November Noise from the proposed wind farm has been predicted to residences in the vicinity based on the ISO noise propagation model and sound power level data provided by the proposed wind turbine generator manufacturer. The applicable environmental noise criteria were determined based on the relevant guidelines and background noise monitoring conducted at three residences in the vicinity of the wind farm. The locations of the turbines and relevant receivers are provided in Appendix A. Background infrasound noise measurements have been conducted at one of the residences south of the proposed wind farm site. These measurements provide an indication of the current infrasound ambient noise environment at the proposed wind farm location. After the wind farm is commissioned, these measurements can be compared with the operational infrasound levels. The assessment concludes that the proposed 8 wind turbines will comply with the derived noise criteria at the nearest noise sensitive receptors. An additional turbine (T8) would not meet the criteria at House 1, but could be considered if arrangements were made for the removal of this sensitive receptor. The derived 37dBA L Aeq criterion at the nearby receptor locations can be achieved with the investigation of suitable noise control measures including the recommended noise attenuation measures. Construction noise impacts can be minimised using the Construction Noise Management Plan. SP0372.R1 Dalveen Wind Farm - Noise Assessment.docx iii Revision 1-20 May 2013

4 Contents 1.0 INTRODUCTION SITE LOCATION AND SURROUNDING AREA PROPOSED DEVELOPMENT Site Construction NOISE ASSESSMENT CRITERIA Environmental Values to be Protected Quantitative Noise Policy Noise Limits for Specific Sources SA EPA Wind Farm Environmental Guidelines Low frequency noise criteria Infrasound noise criteria Backup Diesel Generator Criteria Construction Noise Criteria BASELINE NOISE MONITORING Study Methodology Analysis of Baseline Records Wind Turbine Noise Criteria NOISE MODELLING Methodology Source Sound Power Level Data Noise Model Scenarios IMPACT ASSESSMENT Assessment of Proposed Wind Turbines Assessment of Backup Diesel Generators On-site and Off-site Construction Assessment RECOMMENDATIONS CONCLUSIONS APPENDIX A - FIGURES APPENDIX B - MODELLED SOUND POWER LEVELS APPENDIX C - BACKGROUND NOISE LEVEL SUMMARY C.1 Marini House External C.2 Marini House Internal Infrasound Measurements C.3 Savios House C.4 Site APPENDIX D - ACOUSTIC TERMINOLOGY AND UNITS OF MEASUREMENT D.1 Abbreviations D.2 Glossary of Terms D.3 Human Response to Sound D.4 Sensitivity to Sound Level D.5 Sensitivity to Sound Frequency D.6 Sound Level Meters and A-weighting SP0372.R1 Dalveen Wind Farm - Noise Assessment.docx iv Revision 1-20 May 2013

5 D.7 Tonality and Impulsivity Adjustments to Measured Levels D.8 Response Time D.9 Descriptors for Environmental Noise Assessment SP0372.R1 Dalveen Wind Farm - Noise Assessment.docx v Revision 1-20 May 2013

6 1.0 Introduction This report has been prepared by Savery & Associates Pty Ltd for Muirlawn Pty Ltd to prepare an acoustic assessment of the noise impacts associated with the proposed Dalveen Wind Farm in Queensland. The purpose of the proposed works is to assess the proposed wind farm for compliance with the relevant noise limits at sensitive receptors in accordance with Council s requirements in their request for information dated 21 November Included in Council s letter was the request for: A detailed noise assessment, including the recording of background noise measurements and infrasound levels. Details should also be provided with regards to monitoring methods once operational. Noise from the proposed wind farm has been predicted to residences in the vicinity based on the ISO 9613 noise propagation model and sound power level data provided by the proposed wind turbine generator manufacturers. The applicable environmental noise criteria were determined based on the relevant guidelines and background noise monitoring conducted at three residences in the vicinity of the proposed wind farm. The locations of the turbines and relevant receivers are provided in Appendix A. Background infrasound noise measurements have been conducted at one of the residences south of the proposed wind farm site. These measurements provide an indication of the current infrasound ambient noise environment at the proposed wind farm location. After the wind farm is commissioned, these measurements can be compared with the operational infrasound levels. 2.0 Site Location and surrounding area The Dalveen Wind Farm is proposed to include several wind turbine generators (WTG s) on rural land approximately 16km north of Stanthorpe in Queensland. The site address is Lot 56 Rabbit Fence Road, and incorporates Lot 56 on CP and Lot on RP 84055, Parish of Rosenthal, County of Merivale. The area of the development application is 438 ha. There are a number of residential properties located near the proposed site, as shown in Figure 4 in Appendix A. SP0372.R1 Dalveen Wind Farm - Noise Assessment.docx 6 Revision 1-20 May 2013

7 3.0 Proposed Development The project at Dalveen will include the construction of the following, which are illustrated on Figure 5. Eight wind turbines, each with a power generation capacity of 1.7MW. It should be noted that Figure 5 also includes an additional turbine (T8) to the eight assessed, which is excluded from this assessment. Construction of this turbine would only be possible with the removal of Receptor House 1 as a sensitive receptor; Solar panels in four arrays, with a 6MW capacity; Backup emergency power generation in the form of four to six diesel generators; Site infrastructure, such as maintenance buildings; roads; and electricity. The proposed development is intended as a backup/emergency power generation facility for the local area, for use when the main 110kV power transmission line is undergoing essential maintenance and the 33kV supply falls short of the power requirements for the local Stanthorpe/Pozieres region. In the short-term, this is anticipated to require the use of diesel generators during the daytime only, while the 110kV power transmission line is being upgraded and the construction of the wind farm and solar collection is being undertaken. Once the 110kV power transmission line is upgraded, use of the power generation from the site will only be required in the event of an outage of the 110kV line, which would not be expected to occur more than four times per year, for a nominal six hours at a time. For more than 60% of a typical day, this power capacity would be provided by the wind turbines and solar array. The remaining 40% of the time would require augmentation of the supply power using the diesel generators. The 4 events per year would constitute an emergency for the region in that major rotational load shedding would be required. Currently the network is operating without sufficient alternate power generation and the diesel backup is urgently required to allow for the above mentioned essential maintenance and redundancy. 3.1 Site Construction Construction of the wind turbines, solar array, generators and associated infrastructure is expected to include the following activities: civil works, including site levelling and compaction (utilising typical earthmoving equipment, such as scrapers, graders, excavators, vibratory rollers, front end loaders, backhoes, etc); excavation and foundation construction (utilising backhoes, mobile cranes, generators, powered hand tools, concrete trucks, concrete pumps, welders, etc); installation of site services; SP0372.R1 Dalveen Wind Farm - Noise Assessment.docx 7 Revision 1-20 May 2013

8 building and plant structural erection, plant and equipment installation and fitout (utilising cranes, trucks, scissor-lifts, generators, powered hand tools, welders, etc); and use of haul trucks to provide raw materials. SP0372.R1 Dalveen Wind Farm - Noise Assessment.docx 8 Revision 1-20 May 2013

9 4.0 Noise Assessment Criteria 4.1 Environmental Values to be Protected The Queensland Environmental Protection (Noise) Policy 2008 (EPP (Noise)) identifies the environmental values to be enhanced or protected within the state of Queensland as the qualities of the acoustic environment that are conducive to protecting the health and biodiversity of ecosystems; and the qualities of the acoustic environment that are conducive to human health and wellbeing, including by ensuring a suitable acoustic environment for individuals to do any of the following - sleep; study or learn; be involved in recreation, including relaxation and conversation; and the qualities of the acoustic environment that are conducive to protecting the amenity of the community. 4.2 Quantitative Noise Policy The EPP (Noise) defines Acoustic quality objectives for the environment that are conducive to human health and wellbeing, including the ability for individuals to sleep, study, relax or converse. The acoustic quality objectives relevant to residential locations are reproduced below in Table 1 for reference. However the Explanatory Notes to the EPP (Noise) advises, that these objectives relate to the all-encompassing noise environment, and should not be used as emission limits for individual industries or noise sources. Table 1: EPP (Noise) Acoustic Quality Objectives for Residential Dwellings Part 4 Section 10 of the EPP (Noise) defines the management intent for an activity involving noise as follows: SP0372.R1 Dalveen Wind Farm - Noise Assessment.docx 9 Revision 1-20 May 2013

10 4.3 Noise Limits for Specific Sources For simple and common sources of noise disturbance in the community (e.g. noise from regulated devices, domestic or commercial air-conditioning systems) the acoustic values are protected by prescribed noise offences defined within the Queensland Environmental Protection Act 1994 (EP Act)(updated 1 January 2009). Queensland does not presently have noise criteria for wind farms. Discussions with the Department of Environment and Heritage Protection have confirmed that it is acceptable to use the methodology for setting noise emission limits to protect acoustic environmental values as detailed in the South Australian Environment Protection Authority s Wind Farms Environmental Noise Guidelines (the SA Guidelines). 4.4 SA EPA Wind Farm Environmental Guidelines The SA Guidelines state: The predicted equivalent noise level (L Aeq,10 ), adjusted for tonality in accordance with these guidelines, should not exceed: 35dB(A) at relevant receivers in localities which are primarily intended for rural living 1 ; or 40dB(A) at relevant receivers in localities in other zones; or the background noise (L A90,10 ) by more than 5dB(A); whichever is the greater, at all relevant receivers for wind speed from cut-in to rated power of the WTG and each integer wind speed in between. 4.5 Low frequency noise criteria Where low frequency noise causes concern to residents inside a house it would be desirable to conduct the low frequency noise assessment using internal noise levels. In practice, however, an internal noise level cannot be predicted accurately due to standing waves and resonances 1 A rural living zone is a rural residential lifestyle area intended to have a relatively quiet amenity. The area should not be used for primary production other than to produce food, crops or keep animals for the occupiers own use, consumption and/or enjoyment. The noise amenity should be quieter than in an urban residential area. SP0372.R1 Dalveen Wind Farm - Noise Assessment.docx 10 Revision 1-20 May 2013

11 associated with typical small room dimensions of residential dwellings and access to internal spaces for assessment is not always available. The Environmental Approval conditions generally provided for industrial projects set an internal noise limit of 50dBZ and a difference of no greater than 15dB between dba and dbz levels assessed inside a dwelling. These limits are based on the DEHP Draft Ecoaccess Guideline Assessment of Low Frequency Noise. More practical low frequency noise limits which are typically applied to industrial developments require noise levels outside a sensitive receptor to be below 60dBC and the difference between the internal A-weighted and C-weighted noise levels to be no greater than 20dB 2. Other research suggests a simple method for determining whether a noise level is likely to cause low frequency noise annoyance due to external or internal noise levels, is to subtract the A- weighted overall noise level from the C-weighted overall noise level. If the difference between the two levels is greater than 20dB then the noise is described as being unbalanced and low frequency noise annoyance may result. 3 Due to the complexities of estimating internal noise levels, the assessment will be undertaken using the comparison of the external A-weighted and C-weighted noise levels with the 60dBC overall level and a difference in A-weighted and C-weighted noise levels being no greater than 20dB. 4.6 Infrasound noise criteria Noise at frequencies below 20 Hz is considered to be infrasound (ISO: 7196: ). These low frequencies can still be audible to humans at sufficiently high levels. The level at which the frequency is audible to the human ear is described as the hearing threshold, which has been determined down to frequencies as low as 4 Hz (Watanabe & Møller, ). In general, the lower the frequency the higher the noise level required to make the frequency audible. The guidelines to assess infrasound are not as well established as the assessment of higher frequency noise. In this report infrasound measurements were conducted in accordance with the guidelines set out by the Queensland DEHP and the ISO standard 7196 (Roberts, ) (ISO: 7196: ). The general opinion on the assessment of infrasound is that it should be assessed in reference to the hearing threshold for humans at these lower frequencies. The hearing threshold adopted in 2 Hessler, G.F., 2004 Proposed criteria in residential communities for low-frequency noise emissions from industrial sources, Journal of Noise Control Engineering 52(4), Broner, N. (2011). A simple outdoor criterion for assessment of low frequency noise emission, Acoustics Australia, Vol. 39, No. 1 pp ISO: 7196:1995, Acoustics Frequency-weighting characteristic for infrasound measurements. 5 T. Watanabe and H. Møller, Low Frequency Hearing Thresholds in Pressure Field and in Free Field, Journal of Low Frequency Noise and Vibration, vol. 9, no. 3, C. Roberts, ECOACCES Guideline for the assessment of low frequency noise, in ACOUSTICS 2004, Gold Coast, Australia, SP0372.R1 Dalveen Wind Farm - Noise Assessment.docx 11 Revision 1-20 May 2013

12 this report is based on the research by W. Passchier Vermeer and is also adopted in the Dutch Guideline on low frequency noise and in the guidelines set out by DEHP (Passchier- Vermeer, ) (Geluidshinder, ) (Roberts, ). This threshold is similar but more conservative than the international standard ISO 389 (ISO: 389-7: ). The ISO 389 standard is based on the assumption that 50% of the people can hear noise below the threshold whereas the hearing threshold adopted in this report assumes that only 10% of the people can hear below the hearing threshold. Furthermore the ISO standard extends down to 20 Hz where the hearing threshold adopted in this assessment goes down to 4 Hz, based on the measured thresholds. Because most complaints about low frequency noise come from people aged between 50 and 60 years, it is important to note that the threshold determined by Passchier-Vermeer is based on this age group. The ISO norm is based on the age group between 18 and 25 years. For frequencies below 20 Hz, the G-weighting is often used to assess the impact of noise in the frequency range from 1 Hz to 20 Hz (ISO: 7196: ). The G-weighting gives a high weighting to frequencies between 1 and 20 Hz and a low weighting to frequencies outside this range. A level of 85 db (G) inside dwellings is often adopted as a criteria to protect the environment for infrasound noise exposure as this is similar to the hearing threshold at these frequencies (Roberts, ). 4.7 Backup Diesel Generator Criteria The proposed use of the diesel generators is as follows: To be operational initially during daytime only if required during network upgrades; and After construction of wind turbines and solar array, to be used to provide emergency support to the grid while the 110kV power line is out of service, predicted to be less than 4 events per year with an average duration of less than 6 hours., Given the proposed operation of the diesel generators will occasionally include night time use, the internal sleep disturbance criteria provided by the World Health Organisation (WHO) for constant noise sources, described as 30dBA L Aeq 10 is proposed. Assuming an inside/outside adjustment of 7dBA, this equates to an external noise level criterion of 37dBA L Aeq. 4.8 Construction Noise Criteria Unless a local government has developed specific construction noise management policy, the requirements contained in Section 440 of the Queensland Environmental Protection Act W. Passchier- Vermeer, Beoordeling laagfrequent geluid in woningen, TNO Preventie en Gezondheid (rapport ), N. S. Geluidshinder, NSG-richtlijn laagfrequent geluid, Delft, ISO: 389-7: 2005, Acoustics- Reference zero for the calibration of audiometric equipment - Part 7: Reference threshold of hearing under free-field and diffuse-field listening conditions, International Organization of Standardization, World Health Organization, Guidelines for Community Noise, Geneva, SP0372.R1 Dalveen Wind Farm - Noise Assessment.docx 12 Revision 1-20 May 2013

13 apply. Construction noise levels are typically controlled by limiting the hours in which construction activities are audible at the nearest residential dwellings, to the hours of 6.30 am and 6.30 pm on business days and Saturdays. This approach does not place noise limits on the construction activity during these hours. Outside of these hours the noise is to be inaudible. Where circumstances do not allow the restriction of hours for construction activities, an assessment of the potential noise emissions should be conducted along with the development of a Construction Noise Management Plan (CNMP). SP0372.R1 Dalveen Wind Farm - Noise Assessment.docx 13 Revision 1-20 May 2013

14 5.0 Baseline Noise Monitoring 5.1 Study Methodology Site Selection Baseline measurement site selection was carried out in consultation with Muirlawn project personnel. Properties for monitoring were selected to represent potentially affected residences near to the proposed site of the wind farm, as shown on Figure 4 in Appendix A. For a given property, the following criteria were used to select the physical location of the noise logger: separation from livestock to prevent accidental damage to instrumentation by the livestock; separation from steady sources of noise that should not 11 be regarded as normal features of the ambient noise environment. At a residential location this may include sources such as air-conditioners, pool pumps, septic pumps and radio noise (as examples); separation from nearby vegetation to prevent vegetation noise contamination; and preferences of the landowner for the monitoring site location, based on their knowledge of the property and their understanding of the monitoring location requirements. Data relating to the baseline monitoring sites (shown in Figure 4) are summarised in Table 2. Details of instrumentation, reference weather station location, and photographic records of instrument locations are detailed in the appendices for each site. 11 As per advice in the Qld EPA Noise Measurement Manual SP0372.R1 Dalveen Wind Farm - Noise Assessment.docx 14 Revision 1-20 May 2013

15 Table 2: Measurement Location (Ref. Figure 4) Site N1 Marini Summary of Monitoring Sites Description (based on description in Section 4.4) GPS Coordinates (Latitude, Longitude) Rural living 28 30' '' S ' '' E Appendix Reference C.1 Site N2 Savios Rural (apple plantation) 28 30' '' S ' '' E C.3 Site N3 Paddock Adjacent to property which is rural living 28 30' '' S ' '' E C Noise Monitoring Procedures Noise monitoring was conducted in accordance with the following standards and procedures: Australian Standard AS Acoustics Description and measurement of environmental noise, Part 1: General procedures, and Queensland DEHP 12 Noise Measurement Manual (3rd Edition, 1 March 2000) The monitoring duration was sufficient at each location to ensure that the minimum 2000 data points was obtained, as required by the SA Guidelines Noise Monitoring Instrumentation Baseline noise monitoring was conducted utilising CESVA SC310 Type 1 octave logging sound analysers, CESVA C250 microphones with PA14 preamplifiers and CESVA TK1000 outdoor microphone assemblies at 1.5m microphone height. The loggers have a low noise floor of typically 16dBA or less. Also used on each microphone was a 150mm diameter secondary windscreen GRAS AM0089 for use in high wind speed environments. Noise levels were measured continuously throughout the monitoring period. The logger recorded statistical parameters including L A10 and L A90 at 10 minute intervals with octave frequency bands from 31.5Hz to 16kHz. Baseline infrasound monitoring was conducted utilising the SINUS SK-1 monitoring system in combination with a Microtech MK 222 (Microtech, Gefell, Germany) microphone with a MV203 preamplifier. This combination of microphone, preamplifier and data acquisition system has a good sensitivity over a large frequency range from 2.5 Hz to 10 khz. Instrumentation was field-calibrated prior to and following measurements Meteorological Monitoring Instrumentation Simultaneous monitoring of wind speed, direction, temperature, pressure and humidity conditions was conducted in the vicinity of baseline noise monitoring locations, in accordance 12 DEHP Department of Environment and Heritage Protection. (Queensland Government) SP0372.R1 Dalveen Wind Farm - Noise Assessment.docx 15 Revision 1-20 May 2013

16 with the requirements of AS The meteorological monitoring station sampled the meteorological parameters at two second intervals. The weather data was post-processed to produce summary information for 10 minute intervals corresponding to the noise monitoring intervals. Sensors were located at a 3m reference height. The meteorological monitoring site is indicated on Figure 4, in Appendix A. This weather station was used primarily to determine which time periods were affected by rain. Additional wind speed measurements were also carried out by the client on the site, with wind anemometers at heights 40m, 50m and 60m above ground level. These measurements enabled the wind speed at the hub height to be determined by extrapolation of the wind speed profile to the hub height. 5.2 Analysis of Baseline Records Seasonal Insect and Other Extraneous Noise The DEHP Noise Measurement Manual indicates that the influence of insect noise on baseline noise levels should be carefully considered. During warmer months sampling in rural locations may include significant insect noise contribution to L A90 levels and may misrepresent baseline conditions at other times of the year when insect noise may be less significant (Terlich ). In rural Queensland during dry winter months, significant insect noise may be absent at night. Octave spectral baseline logging has been conducted in the frequency range of 31.5Hz to 16kHz to enable the identification of seasonal or episodic insect and frog noise. The presence (or absence) of such noise was determined from inspection of the spectragram (or sonogram) for the noise-monitoring period. The spectragram is a graphical plot of sound pressure level, represented by colour, versus frequency (y-axis) and time (x-axis). Typically, when insect activity is present, it may be identified as a constant contribution in one or more octave bands above 2kHz, typically in the evening and night periods. If significant evening or night-time insect noise is detected, the insect noise is filtered (i.e. removed) by post-processing the measurement data prior to the correlation to the wind speed. Baseline sampling was conducted in late autumn months between 15 March and 13 April Some insect noise was evident on dusk at a number of monitoring sites but did not continue as a persistent feature throughout the night-time. Some extraneous noise was observed at several monitoring sites which included bird noise around sunset and sunrise. The extraneous noise contribution was removed from the background noise data set Meteorological Conditions Noise data that was affected by excessive wind speed or precipitation was excluded from the aggregate noise level statistics. Intervals with any precipitation or average wind-speeds above 13 Terlich, M The Case for Spectral Measurements of Ambient Noise Levels in the Assessment of Wind Farms Proceedings of the Fourth International Meeting on Wind Turbine Noise, Rome, Italy April. SP0372.R1 Dalveen Wind Farm - Noise Assessment.docx 16 Revision 1-20 May 2013

17 7m/s were cross-referenced to the noise monitoring data and excluded from statistical summary data. For the purposes of standardising measurements and avoiding confusion regarding whether wind is measured at hub height or another height, the SA Guidelines specify for measurements relative to the WTG hub height. In this case, data has been standardised to wind speed at a hub height of 80m agl which corresponds to the wind speeds provided in the WTG manufacturer data Infrasound Analysis From the collected background infrasound noise measurements the average background level over a period of several days from March 28, 2012 was determined for each one-third octave band from 2.5 Hz to 200 Hz. This was carried out separately for the day (7 am - 6 pm), evening (6 pm - 10 pm) and night time periods (10 pm - 7 am). The result is presented in Figure 15 in Appendix C where the average background level is expressed in unweighted L 90 db, i.e. the noise level that is exceeded for 90 % of the time. The human hearing threshold is presented in the same figure to provide a point of reference. As can be observed in Figure 15, the average background level does not exceed the hearing threshold for frequencies below 50 Hz. The average background levels measured start to exceed the hearing threshold only at the 80 Hz one third octave band. The difference between the average background levels in the day evening and night periods is less than 7 db. From the recorded data both the G-weighted L 90 and the L eq were determined for each ten minute recording during the measurement period. The results are presented in Figure 16, Figure 17, Figure 18 and Figure 19, for each day of recorded data. The recorded G-Weighted L 90 and L eq noise levels are much lower than the recommended noise limit of 85 db (G) in dwellings proposed by the Queensland DEHP Draft ECOACCESS Guideline- Assessment of Low Frequency Noise (Roberts, ). This confirms the ambient noise levels have an acceptable level of infrasound noise, particularly as the infrasound would not be audible. 5.3 Wind Turbine Noise Criteria Table 3 summarises the number of remaining data points at each monitoring location, following the removal procedure described in Section to remove insect noise and other extraneous noise. It is noted that the SA Guidelines requires a minimum of 2000 useable data points with background noise levels and wind speed measurements synchronised where at least 500 points are collected in the worst-case wind direction. This data should be between the cut-in wind speed and the speed of rated power. In this case, data between the speed of 3m/s and 14m/s at hub height have been used. SP0372.R1 Dalveen Wind Farm - Noise Assessment.docx 17 Revision 1-20 May 2013

18 Table 3: Location Number of data points at each monitoring location Number of remaining data points Marini 3766 Savios 2676 Site N3 ref. House The measured background noise levels at the monitoring locations were correlated with the wind speed data calculated from the wind data measured on the weather tower. A regression analysis of the data was carried out to determine the line of best fit for the correlations in accordance with the SA Guidelines. The data and regression curves are shown in Appendix C for the three locations. Based on this analysis, the noise criteria determined in accordance with the SA Guidelines at a range of wind speeds within the operating range of the turbines is shown in Table 4. It should be noted that the base criterion of 40dBA was used at the Savios Receptor as this location was noted to be a primary producer in the form of an apple plantation (ref. footnote in Section 4.4). Table 4: Determined Noise Criteria at Wind Speeds Noise Criterion (dba) at Wind Speed (ms -1 ) Location Marini Savios House It is assumed that the noise criteria at the receptor described as House 3, south of the Marini receptor, would be identical to that at the Marini property. As House 3 is significantly further from the site, if compliance with the noise criteria is achieved at the Marini receptor, compliance would also be achieved at House 3. SP0372.R1 Dalveen Wind Farm - Noise Assessment.docx 18 Revision 1-20 May 2013

19 6.0 Noise Modelling 6.1 Methodology An environmental noise model of the site and surrounding area, including the noise sensitive locations, was constructed using ISO (1996), Acoustics - Attenuation of Sound During Propagation Outdoors, Part 2: General Method of Calculation, as implemented in SoundPLAN software. The method predicts A-weighted sound pressure levels under meteorological conditions favourable to propagation (mild temperature inversion with slight downwind) from sources of known sound emission. The overall model accuracy is estimated to be ±3dBA. The graphical noise contours generated by the model represent the envelope of results for noise propagation in all directions (i.e. summary of typical worst-case noise propagation in all directions relative to the noise source). The calculation of sound propagation from the source to the receiver locations is calculated with specific algorithms for the following physical effects: geometrical divergence; atmospheric absorption (in accordance with ISO 9613 Part 1); ground effect; reflection from surfaces; screening by obstacles (horizontal and vertical diffraction); and dense vegetation (none included). The SoundPLAN software produces noise contours by interpolation from predicted grid noise levels at 1.6m above local ground level. Point receptors were also utilised, at a height of 1.6m above ground level at locations representative of the houses in the area. The model terrain was based on elevation data sourced from Muirlawn Pty Ltd and was modelled as 50% absorptive which is consistent with the predominant natural vegetation and accepted modelling methodology both in Australia and internationally. Areas around the generators and substations were modelled as packed earth, approximately 20% absorptive. 6.2 Source Sound Power Level Data The Dalveen Wind Farm will consist of eight (8) General Electric Company wind turbine generators (WTG) with a hub height of 100m. Sound power data used to predict noise impact of these turbines has been taken from a Test Report Technical Documentation - Wind Turbine Generator Systems & 60 Hz prepared by GE Energy. The test was carried out in accordance with International Standard IEC , ed. 2.1: The sound power spectra in octave bands at wind speeds from 7 m/s to the cut-out wind speed of 14 m/s are shown in Table 8 in Appendix B. Each turbine was modelled as a point source at the hub height of 100m agl at each of the specified wind speeds where the WTG is in operation. Sound pressure level data for the proposed diesel generators including spectrum was provided by the manufacturer. Sound power levels were calculated based on the provided dimensions of SP0372.R1 Dalveen Wind Farm - Noise Assessment.docx 19 Revision 1-20 May 2013

20 the equipment. Sound power level data including spectrum for transformer noise was sourced from data on file. The modelled sound power levels are shown in Table 9 in Appendix B. 6.3 Noise Model Scenarios Each of the wind speeds for which data is available for the proposed eight WTG s was modelled as a separate scenario. The eight different speeds (7, 7.7, 8.4, 9.1, 11.1, 12.5 and 14 m/s) encompass the wind speeds of operation, based on the wind at hub height. An additional scenario was modelled including the proposed diesel generators. For this scenario, six generators were modelled to represent the worst-case noise emissions during the initial daytime maintenance activities on the electrical network. This scenario also represents the worstcase noise emissions during any night-time power outages where the generators are required to operate. All scenarios included noise sources for the proposed substations on the site. Transformer noise would be the most significant item in the substations. SP0372.R1 Dalveen Wind Farm - Noise Assessment.docx 20 Revision 1-20 May 2013

21 7.0 Impact Assessment 7.1 Assessment of Proposed Wind Turbines The predicted L Aeq noise levels for the noise model scenarios for the eight different wind speeds described in Section 6.3 are summarised in Table 5. The levels have been predicted at three nearest noise sensitive receptors which are representative of the study area. The noise contours for the worst-case wind speed with regard to both the sound power level and the relevant criteria are shown in Figure 6, Figure 7 and Figure 8 for the 9.1ms -1, 9.7ms -1 and 11.1ms -1 wind speed scenarios respectively. Table 5: Predicted Noise Levels L Aeq at Receptor Locations 8 WTG at 100m hub height Residential Predicted Noise Levels L Aeq (dba) at Wind Speed (ms -1 ) Receptor House Marini Savios The predicted noise levels from the wind turbines have been assessed against the relevant criteria according to the SA Guidelines. The graphical comparison of the predicted noise levels at each receptor with the determined noise criteria are shown in Figure 1 to Figure 3. Figure 1: Predicted Noise Levels at House 1 Receptor for increasing wind speed SP0372.R1 Dalveen Wind Farm - Noise Assessment.docx 21 Revision 1-20 May 2013

22 Figure 2: Predicted Noise Levels at Marini Receptor for increasing wind speed Figure 3: Predicted Noise Levels at Savios Receptor for increasing wind speed SP0372.R1 Dalveen Wind Farm - Noise Assessment.docx 22 Revision 1-20 May 2013

23 Based on the predicted noise levels summarised in Table 5 and shown graphically in Figures 1 to 3, the GE-1.7 turbines are predicted to comply with the relevant noise criteria at all residences for all wind speeds Assessment of Low Frequency Noise from Wind Farm The noise emissions from the wind farm were modelled using the ISO Method implemented in SoundPLAN software to predict the external Z-weighted (db) and C-weighted (dbc) noise levels at the identified receptors, as well as the difference between the A-weighted (dba) and C-weighted (dbc) noise levels. The C-weighting includes nearly all of the low frequency energy of a noise event, while the Z- weighting includes all of the low frequency energy of a noise event. This is contrast to the A- weighting which approximates the frequency response of the human hearing, which is less sensitive to low frequency noise (refer to Appendix D for weighting descriptions). Table 6 provides a summary of the predicted L Ceq at the identified receptors and the difference between C-weighted and A-weighted noise levels, along with the most significant contributors to the C-weighted noise levels. The Z-weighted noise levels have also been included for completeness. Table 6: Assessment of potential external low frequency noise Residential Receptor (ref. Figure 4) Predicted Overall Noise Levels, L Aeq, 1hr L Ceq, 1hr L Zeq, 1hr Difference (L Ceq-LAeq ) Potential LFN problem? Primary sources of dbc levels House No Wind Turbines Marini No Wind Turbines Savios No Wind Turbines Based on the external assessment conducted, it is unlikely that there will be a low frequency noise problem from the proposed wind farm Assessment of Infrasound from Wind Farm The current ambient noise environment does not contain significant audible levels of infrasonic noise. A survey in 2005 of all known published measurements of infrasound from wind turbines at the time, stated The survey indicates that wind turbines of contemporary design with an upwind SP0372.R1 Dalveen Wind Farm - Noise Assessment.docx 23 Revision 1-20 May 2013

24 rotor generate very faint infrasound with a level far below the threshold of perception even at a rather short distance (Jakobsen, ). At a distance of 100 metres from the wind turbines Jakobsen observed that the db(g) level remained below 80 db(g). Therefore the infrasound levels resulting from the proposed wind farm is not expected to exceed the infrasound criteria of 85 db(g) inside the dwellings near the proposed site. This assumption should be confirmed with infrasound measurements once the proposed wind farm is operational Assessment of Substation noise Noise from the substations was included in the noise predictions for the turbines in Section 7.1. At the worst-case receptor (closest to the proposed substations) the component noise level from the substations is calculated to be 25dBA. This noise level is 10dBA below the base level of the SA Guidelines and as such is not anticipated to adversely impact on the amenity of the residences surrounding the proposed wind farm. 7.2 Assessment of Backup Diesel Generators The predicted L Aeq noise levels for the backup diesel generator noise model scenarios described in Section 6.3 are summarised in Table 7. The levels have been predicted at three nearest noise sensitive receptors which are considered representative of the study area. Table 7: Predicted Noise Levels L Aeq 6 Backup Diesel Generators Residential Receptor Predicted Noise Levels L Aeq, adj (dba) House 1 55 Marini 61 Savios 51 To achieve the 37dBA L Aeq at the nearby receptor locations will require the application of attenuation measures to the diesel generators to achieve a noise reduction of at least 24dBA. Attenuation measures to achieve this level of noise reduction should be investigated and may include: modification of the location of the diesel generators to minimise noise emissions to receptors due to increased distance or shielding from terrain. Note that this measure would not achieve the noise criteria in isolation (ie. construction of enclosures described below would also be require, though overall attenuation requirements may reduce if equipment is relocated); 14 Jakobsen, J. 205 Infrasound Emission from Wind Turbines,Journal of low frequency noise, vibration and active control,, vol. 24, no. 3, SP0372.R1 Dalveen Wind Farm - Noise Assessment.docx 24 Revision 1-20 May 2013

25 use of quieter equipment, to reduce the level of attenuation required by an acoustic enclosure, though of a lesser performance; construction of either enclosure around individual generators or enclosure around all generator units, which would include internal absorption inside the enclosure (walls and roof), and attenuated intake and exhaust ventilation paths. Enclosures of proprietary design could be supplied by the generator manufacturer, or alternatively an acoustically treated plantroom building could be designed, or a specialist noise enclosure manufacturer could be engaged to manufacture enclosures to achieve specific attenuation requirements. These treatments should be designed after the location and type of equipment is finalised. 7.3 On-site and Off-site Construction Assessment For construction of the wind farm, solar array, backup diesel generators and associated infrastructure, it is recommended that, where possible, construction activities that may result in noise being audible at the nearest residential dwellings be conducted between the hours of 6.30 am and 6.30 pm on business days and Saturdays. A Construction Noise Management Plan (CNMP) will be prepared and implemented for construction activities so that potential noise impacts during construction and commissioning, (particularly if required outside of standard daytime working hours), are minimised at noise sensitive receptors. The CNMP should include at least the following requirements: for construction of the wind farm, solar array, backup diesel generators and associated infrastructure: normal hours for noise emitting construction activities limited to the period on business days and Saturdays; the Construction Manager will ensure construction is undertaken in accordance with an Environmental Management Plan which will include a Noise Control Plan for any significant out-of-hours works; the Construction Manager will be responsible for establishing processes with relevant contractors to ensure that regular tool-box meetings with workers are held throughout the construction period, where best practice methods to minimise noise impact of construction activities will be reviewed and discussed with the workers; the noise control plan should be in general accordance with AS regarding selection of equipment and processes to be used on site, maintenance of equipment, use of temporary screens and enclosures as appropriate; 15 AS : Guide to Noise Control on Construction, Maintenance and Demolition Sites SP0372.R1 Dalveen Wind Farm - Noise Assessment.docx 25 Revision 1-20 May 2013

26 an effective community consultation program with occupants of the nearest noise sensitive buildings will be implemented and maintained throughout the construction period; a Complaints Register will be established and maintained throughout the construction period. Upon receipt of a complaint, a process to investigate the complaint and undertake suitable remedial action or monitoring shall be initiated with the complaints and results of investigations recorded. SP0372.R1 Dalveen Wind Farm - Noise Assessment.docx 26 Revision 1-20 May 2013

27 8.0 Recommendations Wind Turbines The wind turbine generators should be selected to produce sound power levels not greater than those provided for the proposed WTG in Appendix B. The location of the WTG should be as shown in Appendix A. Diesel Generators To achieve the 37dBA L Aeq at the nearby receptor locations will require the application of attenuation measures to the diesel generators to achieve a noise reduction of at least 24dBA. Attenuation measures to achieve this level of noise reduction should be investigated and may include: modification of the location of the diesel generators to minimise noise emissions to receptors due to increased distance or shielding from terrain. Note that this measure would not achieve the noise criteria in isolation (ie. construction of enclosures described below would also be require, though overall attenuation requirements may reduce if equipment is relocated); use of quieter equipment, to reduce the level of attenuation required by an acoustic enclosure, though of a lesser performance; construction of either enclosure around individual generators or enclosure around all generator units, which would include internal absorption inside the enclosure (walls and roof), and attenuated intake and exhaust ventilation paths. Enclosures of proprietary design could be supplied by the generator manufacturer, or alternatively an acoustically treated plantroom building could be designed, or a specialist noise enclosure manufacturer could be engaged to manufacture enclosures to achieve specific attenuation requirements. These treatments should be designed after the location and type of equipment is finalised. Construction Noise For construction of the wind farm, solar array, backup diesel generators and associated infrastructure, it is recommended that, where possible, construction activities that may result in noise being audible at the nearest residential dwellings be conducted between the hours of 6.30 am and 6.30 pm on weekdays and Saturdays. It is recommended that a Construction Noise Management Plan be prepared and implemented for all construction activities so that potential noise impacts during construction (including commissioning) are minimised at noise sensitive locations. Noise Monitoring once Operational Commissioning measurements are recommended to ensure that target noise levels are achieved for the wind farm site. If access is available, internal infrasound noise measurements should be repeated to confirm that infrasound noise levels continue to be below the hearing threshold. SP0372.R1 Dalveen Wind Farm - Noise Assessment.docx 27 Revision 1-20 May 2013

28 9.0 Conclusions From the assessment of Dalveen wind farm noise impacts the following conclusions can be drawn: Wind Turbines The proposed 8 wind turbines will comply with the derived noise criteria. As mentioned in Section 3.0, it should be noted that Figure 5 includes an additional turbine (T8) to the eight assessed, which is excluded from this assessment. Turbine (T8) would not meet the criteria at House 1, but could be considered if arrangements were made for the removal of this sensitive receptor. Diesel Generators The derived 37dBA L Aeq criterion at the nearby receptor locations can be achieved with the investigation of suitable noise control measures such as the recommended noise attenuation measures. These include: relocation of the generators, use of quieter units and acoustic enclosure of the units. Construction Noise Using the Construction Noise Management Plan, potential noise impacts during construction (including commissioning) will be minimised at noise sensitive locations. SP0372.R1 Dalveen Wind Farm - Noise Assessment.docx 28 Revision 1-20 May 2013

29 Appendix A - Figures Wind Farm Site Savios Receptor Marini Receptor Meteorology station House 1 Receptor Figure 4: Monitoring Locations and Site Location SP0372.R1 Dalveen Wind Farm - Noise Assessment.docx 29 Revision 1-20 May 2013

30 Figure 5: Proposed Site Layout SP0372.R1 Dalveen Wind Farm - Noise Assessment.docx 30 Revision 1-20 May 2013

31 Figure 6: Noise Emissions for 8 operating WTG 9.1m/s GNM 1.6m agl SP0372.R1 Dalveen Wind Farm - Noise Assessment.docx 31 Revision 1-20 May 2013

32 Figure 7: Noise Emissions for 8 operating WTG 9.7m/s GNM 1.6m agl SP0372.R1 Dalveen Wind Farm - Noise Assessment.docx 32 Revision 1-20 May 2013

33 Figure 8: Noise Emissions for 8 operating WTG 11.1m/s GNM 1.6m agl SP0372.R1 Dalveen Wind Farm - Noise Assessment.docx 33 Revision 1-20 May 2013

34 Appendix B - Modelled Sound Power Levels Table 8 : Sound Power Level Spectra of equipment of WTG - GE Hub height wind speed at 80 m [m/s] Source Height agl (m) Linear sound power level (db) in octave centre frequency (Hz) k 2k 4k 8k 16k Total apparent sound power level L WA.k (dba) Linear SWL (db) SP0372.R1 Dalveen Wind Farm - Noise Assessment.docx 34 Revision 1-20 May 2013

35 Table 9 : Sound Power Level Spectra of equipment Transformer and Backup Generators Equipment Item Source Height agl (m) Linear sound power level (db) in octave centre frequency (Hz) k 2k 4k 8k Overall sound power level (dba) Transformer BDITA Caterpillar Diesel Engine - Mechanical Noise 3512BDITA Caterpillar Diesel Engine - Exhaust Noise (unsilenced) Linear SWL (db) SP0372.R1 Dalveen Wind Farm - Noise Assessment.docx 35 Revision 1-20 May 2013

36 Appendix C - Background Noise Level Summary C.1 Marini House External Site No: Marini House (15/03/ :00:00 PM) Calibrator: Bruel & Kjaer 4231 Serial No: S/N Logging Period: Friday, 15 March 2013 to Thursday, 28 March 2013 Instrument: CESVA SC-310 Serial No: S/N T (Logger 7) Logging Period: Thursday, 28 March 2013 to Saturday, 13 April 2013 Instrument: CESVA SC-310 Serial No: S/N T (Logger 12) Reference Weather Station: Reinhardt MWS 9-5, S/N Comments: The logger was located near the corner of the carport attached to the house. Insect noise evident in the data in the 4kHz band, especially during the evening and night periods. SP0372.R1 Dalveen Wind Farm - Noise Assessment.docx 36 Revision 1-20 May 2013

37 Marini House Noise Logger Figure 9: Pictures of Noise Logger Location at Marini House SP0372.R1 Dalveen Wind Farm - Noise Assessment.docx 37 Revision 1-20 May 2013

38 Noise Logging Location Weather station Weather station Figure 10: Pictures of Noise Logger and Weather Station (WS3) Locations at Marini House SP0372.R1 Dalveen Wind Farm - Noise Assessment.docx 38 Revision 1-20 May 2013

39 Figure 11: Aerial Photo showing Noise Logger and Weather Station (WS3) Locations at Marini House SP0372.R1 Dalveen Wind Farm - Noise Assessment.docx 39 Revision 1-20 May 2013

40 Figure 12: Marini House Correlation of Background Noise Level and rated wind speed at reference height of 80m agl SP0372.R1 Dalveen Wind Farm - Noise Assessment.docx 40 Revision 1-20 May 2013

41 C.2 Marini House Internal Infrasound Measurements Site No: Marini House (28/03/201312:50:00 PM) Calibrator: Bruel & Kjaer 4231 Serial No: S/N Logging Period: Friday, 28 March 2013 to Sunday, 31 March 2013 Instrument: SINUS SK-1 Serial No: ST-R-019 SP0372.R1 Dalveen Wind Farm - Noise Assessment.docx 41 Revision 1-20 May 2013

42 Figure 13: Pictures of Infrasound microphone Location inside Marini House Living Room SP0372.R1 Dalveen Wind Farm - Noise Assessment.docx 42 Revision 1-20 May 2013

43 Figure 14: Picture of Infrasound Logging Location inside Marini House Living Room SP0372.R1 Dalveen Wind Farm - Noise Assessment.docx 43 Revision 1-20 May 2013

44 Figure 15: Average unweighted L 90 levels for day, evening and night time periods per one-third octave band. SP0372.R1 Dalveen Wind Farm - Noise Assessment.docx 44 Revision 1-20 May 2013

45 Figure 16: Weighted measured noise levels L eq, L 90 on the 28 th of March. SP0372.R1 Dalveen Wind Farm - Noise Assessment.docx 45 Revision 1-20 May 2013

46 Figure 17: Weighted measured noise levels L eq, L 90 on the 29 th of March. SP0372.R1 Dalveen Wind Farm - Noise Assessment.docx 46 Revision 1-20 May 2013

47 Figure 18: Weighted measured noise levels L eq, L 90 on the 30 th of March. SP0372.R1 Dalveen Wind Farm - Noise Assessment.docx 47 Revision 1-20 May 2013

48 Figure 19: Weighted measured noise levels L eq, L 90 on the 31 th of March. SP0372.R1 Dalveen Wind Farm - Noise Assessment.docx 48 Revision 1-20 May 2013

49 C.3 Savios House Site No: Savios House (15/03/ :00:00 PM) Calibrator: Bruel & Kjaer 4231 Serial No: S/N Logging Period: Friday, 15 March 2013 to Thursday, 28 March 2013 Instrument: CESVA SC-310 Serial No: S/N T (Logger 9) Logging Period: Thursday, 28 March 2013 to Friday, 5 April 2013 Instrument: CESVA SC-310 Serial No: S/N T (Logger 6) Reference Weather Station: Reinhardt MWS 9-5, S/N Comments: The logger was located near the corner of the house, adjacent to apple orchards covered by netting. Insect noise evident in the data in the 4kHz band, especially during the evening and night periods. SP0372.R1 Dalveen Wind Farm - Noise Assessment.docx 49 Revision 1-20 May 2013

50 Figure 20: Pictures from Noise Logger Location at Savios House SP0372.R1 Dalveen Wind Farm - Noise Assessment.docx 50 Revision 1-20 May 2013

51 Figure 21: Aerial Photo showing Noise Logger Location at Savios House SP0372.R1 Dalveen Wind Farm - Noise Assessment.docx 51 Revision 1-20 May 2013

52 Figure 22: Savios House Correlation of Background Noise Level and rated wind speed at reference height of 80m agl SP0372.R1 Dalveen Wind Farm - Noise Assessment.docx 52 Revision 1-20 May 2013

53 C.4 Site 3 Site No: Site 3 (15/03/ :00:00 PM) Calibrator: Bruel & Kjaer 4231 Serial No: S/N Logging Period: Friday, 15 March 2013 to Thursday, 28 March 2013 Instrument: CESVA SC-310 Serial No: S/N T (Logger 1) Logging Period: Thursday, 28 March 2013 to Friday, 5 April 2013 Instrument: CESVA SC-310 Serial No: S/N T (Logger 11) Reference Weather Station: Reinhardt MWS 9-5, S/N Comments: The logger was located in the paddock west of the residential house. Logger was installed in a fenced enclosure in a paddock which occasionally had cattle grazing nearby. Insect noise evident in the data in the 4kHz band, especially during the evening and night periods. SP0372.R1 Dalveen Wind Farm - Noise Assessment.docx 53 Revision 1-20 May 2013

54 Figure 23: Pictures from Noise Logger Location at Site 3 (west of House 1) SP0372.R1 Dalveen Wind Farm - Noise Assessment.docx 54 Revision 1-20 May 2013

55 Figure 24: Aerial Photo showing Noise Logger Location at Site 3 SP0372.R1 Dalveen Wind Farm - Noise Assessment.docx 55 Revision 1-20 May 2013

56 Figure 25: Site 3 Correlation of Background Noise Level and rated wind speed at reference height of 80m agl SP0372.R1 Dalveen Wind Farm - Noise Assessment.docx 56 Revision 1-20 May 2013