Project: FONTERRA STIRLING. Prepared for: Fonterra Limited PO Box 459 Hamilton Attention: Brigid Buckley. Report No.

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1 FONTERRA STIRLING PROPOSED NOISE CONTROL BOUNDARY Rp C 20 September 2016

2 Level 369 Cambridge Terrace PO Box 4071 Christchurch 8140 New Zealand T: F: Project: FONTERRA STIRLING Prepared for: Fonterra Limited PO Box 459 Hamilton 3240 Attention: Brigid Buckley Report No.: Rp C Disclaimer Reports produced by Marshall Day Acoustics Limited are prepared based on the Client s objective and are based on a specific scope, conditions and limitations, as agreed between Marshall Day Acoustics and the Client. Information and/or report(s) prepared by Marshall Day Acoustics may not be suitable for uses other than the original intended objective. No parties other than the Client should use any information and/or report(s) without first conferring with Marshall Day Acoustics. Copyright The concepts and information contained in this document are the property of Marshall Day Acoustics Limited. Use or copying of this document in whole or in part without the written permission of Marshall Day Acoustics constitutes an infringement of copyright. Information shall not be assigned to a third party without prior consent. Document control Status: Rev: Comments Date: Author: Reviewer: Draft Sep 2016 Rob Hay Approved R01 Minor updates 20 Sep 2016 Rob Hay Aaron Staples Approved R02 Minor updates 20 Sep 2016 Rob Hay Aaron Staples

3 EXECUTIVE SUMMARY Marshall Day Acoustics has been engaged to prepare a Noise Control Boundary (NCB) for the Fonterra Stirling site. Our report addresses noise generated by the existing plant along with predicted noise levels should certain noise mitigation work be undertaken. The proposed NCB is primarily based on computer modelling using the known noise generating sources on the site and calculating noise propagation (using ISO ). Noise contours have been prepared that are representative of what can be expected should there be a moderate temperature inversion or light down-wind conditions applying from all sources to all receivers simultaneously. This is described as enhanced propagation and results in elevated noise levels being predicted at all points on the contour. While the proposed NCB is based on the 45 db L Aeq noise contour, to enhance certainty and ease of understanding, we recommend regularising the shape of the NCB to follow property boundaries and easily identifiable geographic features in the first instance and straight lines between easily identifiable points in limited cases. Where the noise model suggests that the 45 db L Aeq contour lies very close to, or appears to weave across a property boundary, we have relied on the actual monitoring results at locations around the plant to clarify whether the regularised NCB should include a property or not. Where the model and actual measurements deviate we place significantly greater weight on the measurements than the model. The proposal will not result in or enable any increase in noise generated by the site. Rather the purpose is to provide certainty to Fonterra, the community and the Council into the future. TABLE OF CONTENTS 1.0 INTRODUCTION SITE & ACTIVITY DESCRITPION Existing Site Site Locality DISTRICT PLAN NOISE STANDARDS OTHER NOISE PERFORMANCE STANDARDS & GUIDELINES Noise Control Boundary EXISTING NOISE ENVIRONMENT PREDICTED NOISE LEVELS Prediction Methodology Model Assumptions & Noise Mitigation Predicted Noise Levels RECOMMENDATIONS CONCLUSIONS APPENDIX A GLOSSARY OF TERMINOLOGY Rp 001 R C Fonterra Stirling - Proposed Noise Control Boundary.docx 3

4 1.0 INTRODUCTION Marshall Day Acoustics (MDA) has been engaged by Fonterra to prepare noise contours and a Noise Control Boundary (NCB) for the Stirling dairy factory located near Balclutha. We have considered noise emissions from the factory as it currently exists and also after certain noise mitigation works have been undertaken. This report summarises the predicted noise contours and the proposed NCB. A glossary of the acoustical terminology used in this report is provided in Appendix A. Figure 1: Existing site and locality, including annual noise monitoring locations 2.0 SITE & ACTIVITY DESCRITPION 2.1 Existing Site Fonterra s Stirling dairy factory is a small cheese and lactose plant with associated storage, milk reception, boiler, wastewater treatment and tanker operations. We understand that there is limited scope for any future expansion at the site and that there are no current plans for expansion. MDA has undertaken annual noise monitoring at the site since 2009 and more recently has investigated tonal noise that has become apparent over the last two seasons. A noise reduction/mitigation programme has been initiated in parallel to the review of the NCB with our involvement. 2.2 Site Locality The site locality and annual noise monitoring locations are shown in Figure 1. In general, compliance with the District Plan noise limits is achieved at all non-fonterra owned dwellings, other than those to the immediate east of the wastewater treatment plant near monitoring location 2 (45 and 47 Mount Wallace Road). The old Manor house (bracketed by monitoring locations 3 and 3B) is owned by Fonterra. Compliance with the District Plan noise limits is marginal at this dwelling and generally is not achieved at the boundary. 3.0 DISTRICT PLAN NOISE STANDARDS The Fonterra Stirling site is within the Clutha District and zoned Industrial. The surrounding land is zoned either Urban or Rural. In both cases the applicable noise limits at the boundary of any residential activity are: Weekdays and weekends: 0700 to 2200 hours 55 db L A to 0700 hours 45 db L A10 Where surrounding land is zoned Urban, the noise limit applies at the site boundary. Where the surrounding land is zoned Rural, the noise limit applies at the notional boundary. No L AFmax noise limits are specified. In addition to the above limits, noise must not exceed 65 db L A10 at the boundary of any other site within the Industrial zone, and any non-residential activity within the Urban and Rural zones. All noise is to be measured and assessed in accordance with the requirements of New Zealand Standard NZS 6801:1991 Measurement of Sound and NZS 6802:1991 Assessment of Environmental Sound. Rp 001 R C Fonterra Stirling - Proposed Noise Control Boundary.docx 4

5 4.0 OTHER NOISE PERFORMANCE STANDARDS & GUIDELINES In addition to the District Plan noise limits, we have considered the following standards and guidelines with respect to assessing the potential noise related effects of the proposed expansion: New Zealand Standard NZS 6802:2008 Acoustics - Environmental noise ; and World Health Organisation guidelines for community noise. Both of these documents suggest that a night-time noise environment of 45 db L Aeq is appropriate for adequate protection of sleep. Similarly, both documents suggest that an upper noise limit of 55 db L Aeq during daytime hours is appropriate to ensure that the risk of the onset of serious annoyance is mitigated. These limits are consistent with the District Plan noise standards for nearby dwellings, although the District Plan uses the L A10 descriptor rather than the L Aeq descriptor. We consider the L Aeq descriptor to be appropriate for this assessment based on the following reasons: The difference between the L A10 and L Aeq noise levels for most major noise sources commonly found on a dairy factory is generally not perceptible to the human ear; The use of the L Aeq descriptor is recommended in the latest versions of the New Zealand Standards for the measurement and assessment of environmental noise; and Use of the L Aeq descriptor is considered to be industry best practice for assessing environmental noise effects. On this basis, we propose a noise limit of 55 db L Aeq(15 min) during daytime hours and 45 db L Aeq(15 min) during the night-time. We expect that the Fonterra site will comply with these limits at all non-fonterra owned dwellings after additional noise mitigation, other than the first dwelling to the immediate east of the wastewater treatment plant. We propose that the above noise limits apply at a predefined Noise Control Boundary (NCB) for the site. The NCB concept is discussed in detail in the following section. 4.1 Noise Control Boundary MDA has previously been involved in the development and implementation of NCB s used for large sites that produce significant noise around New Zealand, including Fonterra s Edendale, Studholme, Whareroa and Pahiatua sites (amongst others). Based on this experience, we consider the key benefits of a NCB as follows: Provides a greater degree of certainty for both Fonterra and the general public with respect to the extent of noise permitted from the site as the result of the expansion and any other future developments; and Compliance is typically much more straight-forward to assess than a notional boundary rule. The proposed NCB (purple line) and related planning information is provided in Figure 2. The methodology used to define the proposed NCB is discussed in greater detail below. Figure 2: Proposed Noise Control Boundary Rp 001 R C Fonterra Stirling - Proposed Noise Control Boundary.docx 5

6 5.0 EXISTING NOISE ENVIRONMENT MDA has performed annual noise monitoring around the Fonterra Stirling site since 2009, which has enabled us to establish existing noise levels under fine, calm conditions. We have also visited the site several times in the last 18 months to conduct an extensive survey of noise sources on site. The noise environment in the vicinity of the Stirling factory is dominated by the existing dairy factory operation and, along with periodic contribution from rail on the main trunk line. These measurements are summarised in Table 1. Note that all data is reported as db L Aeq to enable direct comparison with the proposed noise rules and NCB. Where plant noise dominates a measurement location there is typically a 1 db difference between the L Aeq and L A10, with the L A10 being greater. Table 1: Historical noise monitoring results Season Measured noise level (db L Aeq ) 1 2 3* 3B / / / / / / / (48) (46) * Position superseded. 1 Noise level penalised by 5 db for tonality. Actual measured noise level is brackets. + No L Aeq data available. L A10 value reported. Data collected during these detailed surveys and our routine annual noise monitoring has been used to build and calibrate an extensive noise model of the site. This model has been developed using the internationally recognised noise modelling software package SoundPLAN which takes into account the directivity and propagation of noise, including effects related to ground and atmospheric absorption and meteorological effects. Noise modelling methodology is discussed in more detail in Section 6.0. While the results of this modelling compare closely to measurements on and around the site, we consider the model to be conservative (i.e. predicts slightly greater noise levels) as it assumes a light downwind noise propagation in all directions around the plant simultaneously. In addition, where there is a discrepancy between the model and site measurements, after accounting for meteorological effects, we have relied on our interpretation of the site measurements to inform the location of the NCB. Our model of the existing 15-minute peak noise emissions from the existing site (with tonality eliminated as currently committed to) is provided in Figure 3. The model includes tanker movements and all fixed plant operating at full capacity. The 15-minute peak refers to the 15 minute period when there is greatest on-site tanker activity. This typically occurs during a driver shift change. The model of existing site noise emissions does not include traffic on public roads or trains on the main south rail line. Ambient noise levels in the area may be significantly higher than the predicted noise levels for the dairy factory alone when traffic noise and rail noise is included, particularly during the day. Rp 001 R C Fonterra Stirling - Proposed Noise Control Boundary.docx 6

7 Figure 3: Fonterra Stirling dairy factory existing noise emissions (tonality treated) Rp 001 R C Fonterra Stirling - Proposed Noise Control Boundary.docx 7

8 6.0 PREDICTED NOISE LEVELS 6.1 Prediction Methodology In order to accurately predict noise levels, detailed noise models have been prepared using SoundPLAN. As mentioned above, this software takes into account the directivity and propagation of noise, including effects relating to ground and atmospheric absorption and meteorological effects. The calculations are based on ISO :1996 Acoustics - Attenuation of sound during propagation outdoors - Part 2: General method of calculation. This standard adopts the conservative approach of assuming that wind is always blowing from the noise source towards the receiver. The calculations also hold for average propagation under a well developed moderate ground based temperature inversion, such as commonly occurs on clear, calm night. All models are based on worst-case 15 minute scenarios involving peak heavy vehicle movements. As such, noise emissions will generally be lower than the levels predicted in this report. 6.2 Model Assumptions & Noise Mitigation Before preparing the models of predicted noise levels presented below, we engaged in an extensive design and consultation process with Fonterra. Our model is based on a range of noise control measures that are to be implemented in order to correct the tonality that has become apparent over the two previous seasons. These mitigation measures will also result in a small reduction in the overall noise level, particularly to the west and north of the site. These include, but are not limited to: Elimination of existing tonality; and Construction of noise control fences at selected locations. 6.3 Predicted Noise Levels Based on the noise mitigation measures and assumptions described above we have prepared a noise contour map illustrating predicted noise levels. This is provided in Figure 4. The noise contours and the proposed NCB are provided in Figure 5. Rp 001 R C Fonterra Stirling - Proposed Noise Control Boundary.docx Page 8 of 12

9 Figure 4: Fonterra Stirling dairy factory with tonality treated and noise control fences in place Rp 001 R C Fonterra Stirling - Proposed Noise Control Boundary.docx Page 9 of 12

10 Figure 5: Fonterra Stirling dairy factory predicted noise contours after noise mitigation showing proposed Noise Control Boundary (NCB) Rp 001 R C Fonterra Stirling - Proposed Noise Control Boundary.docx Page 10 of 12

11 7.0 RECOMMENDATIONS To ensure that the site continues to operate in a manner which results in acceptable noise effects, we recommend that the District Plan incorporate the following suggested text. Noise from the operation of the Fonterra Stirling dairy factory, including all ancillary equipment, maintenance activities, and operation of road transport on site shall not exceed the following limits when measured at or beyond the Noise Control Boundary: Weekdays and Weekends 7am 10pm 10pm 7am 55 db L Aeq (15 min) 45 db L Aeq (15 min) and 75 db L AFmax Noise shall be measured in accordance with New Zealand Standards NZS 6801:2008 Acoustics - Measurement of environmental sound and assessed in accordance with NZS 6802:2008 Acoustics- Environmental noise. These noise performance standards and NCB should be combined with suitable policies, objectives and reverse sensitivity standards, which we understand Fonterra is also preparing. 8.0 CONCLUSIONS Marshall Day Acoustics has prepared a detailed noise model of the Fonterra Stirling site as it currently exists and also with a number of noise treatment/mitigation items. The resulting contours have been interpreted, alongside actual site measurements, to generate a proposed Noise Control Boundary for incorporation into the District Plan alongside a suitable set of objectives, policies and reverse sensitivity standards. The proposed NCB will provide enhanced certainty for Fonterra, the local community and Council by providing a clear demarcation of the extent of noise emissions from the site and any potential noise effects that may arise. We predict that cumulative noise levels from the site will remain no greater than 45 db L Aeq (15 min) at the nearest non-fonterra owned dwellings (with the exception of 45 Mount Wallace Road), which is consistent with the District Plan noise limits, the latest New Zealand environmental noise assessment standards, and guidance provided by the World Health Organisation for the protection of sleep amenity. On this basis, we consider the noise related effects of the proposal to be acceptable. It is important to note that the adoption of the proposed NCB will not result in, nor permit, a greater level of noise emission that is already occurring from the factory. Rp 001 R C Fonterra Stirling - Proposed Noise Control Boundary.docx Page 11 of 12

12 APPENDIX A GLOSSARY OF TERMINOLOGY Noise Masking Noise Ambient SPL or L P db A-weighting L Aeq (t) L A10 L Amax NZS 6801:2008 NZS 6802:2008 NZS 6803:1999 ISO :1996 A sound that is unwanted by, or distracting to, the receiver. Intentional background noise that is not disturbing, but due to its presence causes other unwanted noises to be less intelligible, noticeable and distracting. The ambient noise level is the noise level measured in the absence of the intrusive noise or the noise requiring control. Ambient noise levels are frequently measured to determine the situation prior to the addition of a new noise source. Sound Pressure Level A logarithmic ratio of a sound pressure measured at distance, relative to the threshold of hearing (20 µpa RMS) and expressed in decibels. Decibel The unit of sound level. Expressed as a logarithmic ratio of sound pressure P relative to a reference pressure of Pr=20 µpa i.e. db = 20 x log(p/pr) The process by which noise levels are corrected to account for the non-linear frequency response of the human ear. The equivalent continuous (time-averaged) A-weighted sound level. This is commonly referred to as the average noise level. The suffix "t" represents the time period to which the noise level relates, e.g. (8 h) would represent a period of 8 hours, (15 min) would represent a period of 15 minutes and ( ) would represent a measurement time between 2200 and 0700 hours. The A-weighted noise level equalled or exceeded for 10% of the measurement period. This is commonly referred to as the average maximum noise level. The A-weighted maximum noise level. The highest noise level which occurs during the measurement period. New Zealand Standard NZS 6801:2008 Acoustics Measurement of environmental sound New Zealand Standard NZS 6802:2008 Acoustics Environmental noise New Zealand Standard NZS 6803: 1999 Acoustics - Construction noise International Standard ISO :1996 "Acoustics - Attenuation of sound during propagation outdoors - Part 2: General method of calculation" Rp 001 R C Fonterra Stirling - Proposed Noise Control Boundary.docx 12