WRITTEN PUBLIC COMMENTS
NOT READ INTO THE RECORD
From: Antony Spencer
To: City Clerk
Cc: [email protected]
Subject: Re: Virginia Robinson gardens Noise report
Date: Tuesday, August 23, 2022 6:53:43 PM
Attachments: VRG - Noise.pdf
VRG - Noise.pdf
VRG - Noise.pdf
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<VRG - Noise.pdf>
On 23 Aug 2022, at 07:58, Antony Spencer <[email protected]> wrote:
Dear vice chair
Thank you very much for spending so much time with me this morning which is much appreciated.
I enclose here with a noise report that I asked my consultant to produce for me ,as a briefing paper .
This is a very high level note ,I am sure that your noise department/ professionals will be able to endorse the contents .
I look forward to seeing you this evening
Best wishes
Antony Spencer
<VRG - Noise.pdf>
INCREASED USAGE OF VRG - NOISE 0051346-0820-0
VIRGINIA ROBERTS GARDEN (VRG) 7TH DECEMBER 2021
P R O J E C T N O T E
INTRODUCTION
1.1. This Project Note provides comments regarding the noise issues associated with the proposed Supplemental Environmental Impact Report (SEIR) for the increased usage of Virginia Robinson Gardens, 1075 Carolyn Way, Beverley Hills, CA (VRG).
UNDERSTANDING OF THE PROPOSAL
1.2. It is understood that the proposed changes to the use of the VRG will mean a considerable increase in activity with a doubling of daily visitors, a 6-fold increase in events, including use of amplified sound, and an extension of activities from 4pm to sunset (which is understood to be in the mid-evening around 8.00 pm in mid-summer), with associated increases in vehicular traffic to and from the VRG.
BASELINE BACKGROUND NOISE LEVELS AND AMBIENT SOUNDSCAPE
1.3. The effect of noise on people and the use of their homes not only depends on how loud the noise is in terms of noise level, and any relevant regulatory controls; but also, how the noise in question relates to existing background noise levels and the ambient soundscape.
1.4. For example, this would include considering the following:
− What might be the difference between representative background noise levels at outdoor amenity spaces at residential properties and the predicted noise from VRG? and,
DOCUMENT CONTROL
DOCUMENT TITLE VIRGINIA ROBERTS GARDEN (VRG) REVISION R00 DOCUMENT NUMBER 0051346-0820-0 ISSUE DATE 7
TH DECEMBER 2021
PROJECT NAME INCREASED USAGE OF VRG - NOISE AUTHOR DANI FIUMICELLI
STATUS ISSUE CHECKED JS
ISSUED TO ANTONY SPENCER PASSED DB
INCREASED USAGE OF VRG - NOISE 0051346-0820-0
VIRGINIA ROBERTS GARDEN (VRG) 7TH DECEMBER 2021
− What might be the increase in noise level at outdoor amenity spaces at residential properties due to the predicted noise from VRG? and, − Does the noise from VRG contain characteristics that increase its impact? For example, the low frequency bass thump of modern amplified music and the information content of amplified speech mean that the noise has a greater impact compared to the relatively anonymous sound such as steady traffic noise from busy but distant highways.
− How might the noise from VRG contrast or blend with the existing soundscape at outdoor amenity spaces at residential properties ? i.e. how congruous will the noise from VRG be in the context of the existing sounds making up soundscape in the area.
1.5. Consequently, any noise assessment for the SEIR should include a comprehensive baseline noise survey and observations of the soundscape at locations representative of residential properties around the VRG.
1.6. Background noise levels and the ambient soundscape typically vary depending on t he time of the day, evening or night, between weekdays and weekends day of the week, and with the weather conditions.
1.7. Therefore, any baseline survey should be sufficiently long enough to capture sufficient data so that outliers and anomalous values can be rejected and there remain enough values to be able to understand the variability of the baseline noise levels through day, evening and night periods and use statistical analysis to establish representative background noise levels and observations of the ambient soundscape.
1.8. Typically, this requires continual monitoring for 15 minute periods over a minimum of a 7 day period to be able to capture sufficient data to understand and manage the associated uncertainties so that any derived background noise levels and ambient soundscape observations can be confidently relied upon.
SPATIAL EXTENT OF THE NOISE ASSESSMENT FOR THE SEIR
1.9. The district around VRG is almost exclusively residential in character with correspondingly relatively quiet background noise levels and a tranquil ambient soundscape. Noise will INCREASED USAGE OF VRG - NOISE 0051346-0820-0
VIRGINIA ROBERTS GARDEN (VRG) 7TH DECEMBER 2021
therefore not decay to below background noise levels or stop being incongruous in the context of the ambient soundscape until it has travelled some distance from the VRG.
1.10. Consequently, intensification of existing and introduction of more noise generating activities at the VRG has potential to cause disturbance and disruption to not only residents of properties adjacent to the VRG but also those some distance from the premises.
1.11. It is therefore suggested that the spatial extent of the noise assessment should be carefully considered and a distance of 750 feet from the boundary of the VRG is considered a likely minimum.
SOURCES OF NOISE
1.12. The main sources of noise associated with the proposed changes to the use of VRG that should be included in the SEIR include the following:
− Amplified music and speech
− Crowds
− Traffic
− Miscellaneous e.g. temporary plant installations such a generators or refrigeration equipment for catering, and fireworks.
NOISE PREDICTIONS
1.13. Assessment of the noise from the proposed increased use of the VRG will be dependent on theoretical prediction of noise propagation.
1.14. There are several methods of predicting the propagation of noise e.g. ISO 9613 is a common method.
1.15. Whatever method is used to predict noise levels from the VRG it should include the following parameters that influence the propagation of noise
− Robust source levels i.e. the sound power and frequency spectrum of the source should be realistic and verifiable.
− The effect of distance (geometric spreading).
INCREASED USAGE OF VRG - NOISE 0051346-0820-0
VIRGINIA ROBERTS GARDEN (VRG) 7TH DECEMBER 2021
− Source directivity characteristics.
− Source emission characteristics e.g. some Public Address system (PAs) propagate as a line source at a lower rate of decay before the decay increases to that of a point source at a faster rate.
− The effects of topography and buildings acting as barriers to the propagation of noise
− Ground absorption.
− Air absorption.
− Relative humidity and temperature.
− Meteorological conditions e.g. wind direction.
− Acoustic reflections other than from the ground.
NOISE PREDICTION VERIFICATION
1.16. Whilst the prediction of the noise from VRG will be a starting point in the noise assessment for the SEIR, there will be the opportunity to verify the predictions from amplified sound by installing a temporary PA at the VGR and carrying out noise propagation tests.
1.17. Such a test would involve temporary installation of a PA configured in a way typical of likely an event at VGR and playing test examples of sound at various levels, whilst simultaneously measuring at a reference point at the VRG e.g. the sound mixing/control point at VRG, and at representative residential locations at various distances around the VRG.
1.18. The propagation test would provide real world empirical data directly relevant to the VRG and surrounding locations that could be used to verify the noise predictions and reduce the inevitable uncertainties associated with theoretical prediction of noise propagation so that, they could be more confidently relied upon in the noise assessment in the SEIR.
SUMMARY
1.19. Noise from the proposed changes and intensification of use of the VGR has the potential to cause significant adverse effects to people living at and using residential properties adjacent to and some distance from the VGR.
INCREASED USAGE OF VRG - NOISE 0051346-0820-0
VIRGINIA ROBERTS GARDEN (VRG) 7TH DECEMBER 2021
1.20. As well as considering regulatory requirements, the assessment of the noise in the SEIR from the proposed changes at VGR should include a comprehensive bassline noise survey to establish representative background noise levels and ambient sound conditions in outdoor amenity spaces at residential properties adjacent too, and to at least 750 feet from, the perimeter of the VGR.
1.21. The assessment of the impact of noise from the VGR should include evaluation against regulatory requirements, and of the difference between the noise from VGR and baseline noise, the increase in noise levels comparted to existing conditions, allow for any acoustic characterises that might enhance the impact of the noise, and evaluate how congruous the noise will be with the existing soundscape.
1.22. The sources of noise included in the SEIR assessment should include all those likely to be audible beyond the boundary of the VGR.
1.23. The prediction of the propagation of noise from sources at the VGR should be based on reliable source data and include relevant factors that influence propagation of noise outdoors.
1.24. Predictions of amplified noise should be verified by a propagation test using a temporarily installed PA and simultaneous measurements at the VGR and various representative residential properties adjacent to and at multiple distances from the pre mises.
INCREASED USAGE OF VRG - NOISE 0051346-0820-0
VIRGINIA ROBERTS GARDEN (VRG) 7TH DECEMBER 2021
PROJECT NOTE DISCLAIMER:
This project note was prepared by Vanguardia Limited (“VL”) for the sole benefit, use and information of Mr Antony Spencer for the purpose stated in the introduction. VL assumes no liability or responsibility for any reliance placed on this note by any third party for any actions taken by any third party in reliance of the information contained herein. VL’s responsibility regarding the contents of the note shall be limited to the purpose for which the note was produced and shall be subject to the express contract terms with Mr Spencer. The note shall not be construed as investment or financial advice. The findings of this note are based on the available information as set out in this note.
The contents of this Note have been prepared for the sole benefit, use and information of Mr Spencer for the purposes set out in the Note or instructions commissioning it and shall be subject to the express contract terms with Mr Spencer. Vanguardia Limited assumes no liability or responsibility for any reliance placed on this Note by any third party. All data, concepts and proposals are Copyright © 2021 Vanguardia Ltd. All rights reserved. Issued in commercial confidence.
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