ZONES 1 AND 2 - STORAGE AND DISTRIBUTION

AUGUST 2019 CONFIDENTIAL

Omega Warrington Limited

ZONES 1 AND 2 - STORAGE AND DISTRIBUTION Noise Mitigation Assessment



CONFIDENTIAL

TYPE OF DOCUMENT (VERSION) CONFIDENTIAL

PROJECT NO. 70063279/001

DATE: AUGUST 2019



CONFIDENTIAL

WSP

8 First Street Manchester M15 4RP

Phone: +44 161 200 5000

WSP.com

ZONES 1 AND 2 - STORAGE AND DISTRIBUTION CONFIDENTIAL | WSP Project No.: 70063279/001 August 2019 Omega Warrington Limited

QUALITY CONTROL

Issue/revision First issue Revision 1 Revision 2 Revision 3

Remarks Final

Date 15 August 2019

Prepared by James Powlson

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Checked by Robin Brown

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Authorised by James Powlson

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Project number 70063279/001

Report number 70063279_001 Final

File reference \\uk.wspgroup.com\Central Data\Projects\700632xx\70063279 - Omega Zones 1 and 2 - Acoustics Planning Support\03 WIP\AC Acoustics\05 Reports

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CONTENTS

1 INTRODUCTION 1

2 SITE DESCRIPTION AND PROPOSED DEVELOPMENT 3

2.1 SITE DESCRIPTION 3

2.2 PROPOSED DEVELOPMENT 5

3 PLANNING CONDITIONS AND ASSESSMENT GUIDANCE 7

3.1 PLANNING CONDITIONS 7

3.2 BRITISH STANDARDS AND GUIDANCE 8

BS8233:2014: GUIDANCE ON SOUND INSULATION AND NOISE REDUCTION FOR BUILDINGS 8

BS4142: 2014: METHODS FOR RATING AND ASSESSING INDUSTRIAL AND COMMERCIAL SOUND 9

4 BASELINE NOISE SURVEY 11

4.1 PURPOSE 11

4.2 TIMING AND DURATION 11

4.3 MEASUREMENT LOCATION 11

4.4 METEOROLOGICAL CONDITIONS 11

4.5 MEASUREMENT EQUIPMENT AND CALIBRATION 11

4.6 MEASUREMENT RESULTS 12

BACKGROUND SOUND LEVELS 12

5 ASSESSMENT 13

5.1 NOISE MODEL 13

SOURCE NOISE DATA 14

5.2 MODELLED SCENARIOS 15


5.3 PREDICTED OPERATIONAL NOISE LEVELS 16

RECEPTOR LEVELS 16

NOISE CONTOURS ERROR! BOOKMARK NOT DEFINED.

5.4 BS8233 ASSESSMENT 18

5.5 BS4142 ASSESSMENT 18

6 MITIGATION 20

6.1 SUMMARY 20

7 CONCLUSION 22

APPENDICES

GLOSSARY OF ACOUSTIC TERMINOLOGY

MEASUREMENT DATA ANALYSIS

ZONES 1 AND 2 - STORAGE AND DISTRIBUTION CONFIDENTIAL | WSP Project No.: 70063279/001 August 2019 Omega Warrington Limited Page 1 of 23

1 INTRODUCTION

1.1.1. WSP has been appointed by Omega Warrington Limited to provide acoustic consultancy services to assist in the layout and design of a B2/B8 development proposed to form part of Omega Warrington. This appointment was made to ensure that good practice acoustic design and layout techniques were employed in the development of the scheme layout design, to minimise the potential for noise impact from the Proposed Development.

1.1.2. The development is proposed south of Skyline Drive and west of Burtonwood Road, with the plot benefiting from outline planning permission (planning reference 2017/30371). The redline boundary of the plot falls entirely within the Zone 1 and 2 areas of that outline permission.

1.1.3. WSP’s commission has included the provision of good practice acoustic design input to the Scheme, as well as the noise impact assessment works necessary to ensure compliance with the requirements of noise related planning condition numbers 25 and 26 of the outline approval.

1.1.4. Condition 25 requires that in conjunction with any B2/B8 reserved matters application for Zone 1, the applicant shall submit to the Local Authority the details of any acoustic protection measures required on the site boundary with any residential areas within the Omega development. This is to include the details of any acoustic fencing / acoustic bunding and the details of any stand-off zone which may be necessary to construct a physical barrier and enable acoustic attenuation to take place.

1.1.5. The fundamental requirement of condition 25 is the delivery of any necessary acoustic screening / standoff to facilitate compliance with target noise level criteria detailed within BS8233:2014: Guidance on sound insulation and noise reduction for buildings (BS8233), at residential development areas to the south of the Proposed Development and within the Omega site. Once agreed with the Local Authority any acoustic measures that are identified as necessary, are to be implemented in full prior to the commencement of use of the proposed B2/B8 development.

1.1.6. Condition 26 requires that an acoustic assessment is undertaken to address noise generation potential from any proposed B2/B8 development and potential associated impact on permitted residential development to the south of the redline boundary of the outline permission (i.e. as also referenced by 25), and also existing residential dwellings beyond Burtonwood Road. The assessment is required to consider the acoustic mitigation offered by any barrier ‘required separately or already in existence’ and that measures shall be proposed wherever the resultant noise levels will either exceed guideline values presented in BS8233 at residential plots, or where an assessment following BS4142:2014: Method for rating and assessing industrial and commercial sound (BS4142) indicates that rated noise levels may give an increased likelihood of complaints. The condition requires that any agreed mitigation measures shall be implemented in full and shall be retained for the duration of that use.

1.1.7. It should be noted that the previous Scheme layout presented as part of the 2017/30371 outline application included B2/B8 service yard areas (key areas of potential noise generation) immediately adjacent to the southern site boundary (which is with Zone 1 permitted residential development) and also facing east towards existing dwellings east of Burtonwood Road.

1.1.8. A more effective means of providing noise mitigation than the retrospective addition of site boundary bunds / acoustic screening is to incorporate best practice acoustic design measures in the development of the Scheme layout. These measures could include locating service yards such that


they are screened from sensitive receptors either by the development itself (which also ensures additional distance attention) or by existing topographic features and locating service yards in the parts of the site that are already subject to high noise level. This approach has been adopted in the development of the Scheme layout deign for which a reserved matters application is being submitted. As a result, the Proposed Development includes significant design led improvements over the layout presented as part of the outline application.

1.1.9. For example, all proposed services areas are now located on the north side of the proposed B2/B8 development units. This ensures the attenuation of noise due to distance and that screening is maximised and significantly greater than that associated with the previous outline Scheme layout. The design has also ensured that service yard areas are located on the site areas subject to the highest road traffic noise levels.

1.1.10. All service yards are fully screened from both existing and proposed residential receptors, either by the proposed B2/B8 units themselves, or by existing topography. N.B. Burtonwood Road separates the site from existing dwellings to the east, and is some 5m above the proposed service yards and the existing dwellings, thereby forming a substantial acoustic screen. This screening is further enhanced as a result of an existing 2m acoustic barrier on the raised edge of the Burtonwood Road Embankment adjacent to the southbound carriageway (that is closest to these dwellings), increasing the screening to 7m.

1.1.11. Notwithstanding the design measures that are in place, this report presents an appraisal of potential noise impact for compliance with Conditions 25 and 26.

1.1.12. To inform the assessment, a detailed baseline noise survey has been undertaken to establish the prevailing ambient and background noise levels in the vicinity of existing dwellings east of Burtonwood Road. A detailed noise level prediction exercise has then been undertaken for the Scheme using a 3D noise model. The noise modelling results have been assessed with reference to both BS4142 and BS8233 as required by conditions 25 and 26.

1.1.13. This report is necessary technical in nature, so to assist the reader, a glossary of acoustic terminology is presented in Appendix A.


2 SITE DESCRIPTION AND PROPOSED DEVELOPMENT

2.1 SITE DESCRIPTION 2.1.1. The site is located in the north-eastern portion of the Omega Development, and is bounded by

Burtonwood Road to the east and Skyline Drive and an existing Dominos distribution unit to the north, beyond which is the M62 (Liverpool to Manchester).

2.1.2. To the west the site is bounded by existing ASDA distribution unit. To the south the site is bounded open land which also forms part of the wider Omega Development. The redline boundary for the site is presented in Figure 1 below.

2.1.3. The land to the south has outline planning permission for a combination of development types including B2, B8 and residential.

2.1.4. Burtonwood Road, east of the site, connects the M62 (Junction 8) with the western side of Warrington including Great Sankey and Penketh. This road is on a substantial embankment (5m) as it passes the north-eastern corner of the site (more details are presented below).

2.1.5. The closest noise sensitive receptors to the site are existing residential dwellings to the east of Burtonwood Road and land proposed for residential development to the south.

2.1.6. The existing noise environment at these locations is dominated by road traffic noise. In particular, existing dwellings east of Burtonwood Road are subject to noise from Burtonwood Road itself, the M62 to the north, routes forming the M62 Junction 8 to the north and Charon Way to the north (which connects Burtonwood Road to the Gemini Trading Estate).

2.1.7. Charon Way was recently subject to reconfiguration, moving it closer to existing dwellings east of Burtonwood Road. This reconfiguration included the installation of a continuous 2m high acoustic fence along its southern edge. This acoustic fence also extends along the eastern side of Burtonwood Road. This fence increases the effective screening of the Burtonwood Road embankment from 5m to 7m.

2.1.8. Image 1 below, shows the north-east corner of the site looking from Skyline Drive towards Burtonwood Road. This image shows the Burtonwood Road embankment, the acoustic barrier located on the far side of Burtonwood Road and the closest existing dwellings beyond (all windows and external living spaces are screened).


Figure 1 Redline Site Boundary

Image 1 Burtonwood Road Embankment

Dwellings Acoustic Fence Embankment Burtonwood Rd Proposed site


2.2 PROPOSED DEVELOPMENT 2.2.1. A reserved matters planning application is being submitted for a Scheme comprising three B2/B8

units with associated service yards, Figure 2 presents the Scheme layout.

Figure 2 Scheme Layout

2.2.2. It can be seen that the following good practice design measures have been employed in the development of the Scheme layout:

All service yards are located on the north side of the proposed units, close to the M62 and Burtonwood Road, and are therefore in the parts of the site subject to the highest prevailing noise levels.

The service yard locations ensure a substantial minimum distance separation distance of 170m to proposed residential development areas to the south.

All service yards are fully screened from proposed residential development areas to the south by the proposed B2/B8 units themselves (which are proposed to be approximately 18.6m in height).

All service yards are fully screened from existing residential dwellings on the east side of Burtonwood Road, either by the proposed B2/B8 units themselves, or by the existing earthworks on which Burtonwood Road is located. This road is on a steep-sided, wide embankment next to the site, being approximately 5m above the ground level of the proposed Unit 2 service yard on one side and the existing dwellings on the other.

The acoustic performance of the above earthworks is further enhanced by the existing 2m high acoustic fence on the south side of Charon Way / east side of Burtonwood Road. This acoustic fence is located on the raised edge of the earthworks closest to the existing dwellings. In total, there is therefore an approximate 7m high acoustic screen between existing dwellings east of Burtonwood Road and the closest proposed service yards.

Unit 2 has been kept as far north as possible to ensure that the unit itself provides additional acoustic screening to as many dwellings on the east side of Burtonwood Road as possible.


The proposed finished ground levels of the service yards have been kept low (approximately at existing ground level) to retain maximum benefit from the 7m acoustic screen to the east of Unit 2.

Regardless of the above, there is a minimum horizontal separation distance of approximately 100m between existing dwellings east of Burtonwood Road and the closest proposed service yard (that of Unit 2), with Burtonwood Road and associated embankment and acoustic fence in-between.


3 PLANNING CONDITIONS AND ASSESSMENT GUIDANCE

3.1 PLANNING CONDITIONS 3.1.1. The plot benefits from outline planning permission, reference 2017/30371. Conditions 25 and 26 of

this outline permission are duplicated as follows:

25 - NOISE – ACOUSTIC BARRIER & STAND-OFF ZONE – B2/B8 AND C3 ZONE BOUNDARY. In conjunction with any B2/B8 reserved matters application for Zone 1, the applicant shall submit written details of any acoustic protection measures to be implemented on the boundary of the site with any residential area within the Omega boundary to the local planning authority. Any acoustic protection measures shall be clearly identified within the proposal and shall include details of the height of any acoustic fencing/acoustic bunding – or combination thereof, as well as details of any subsequent stand-off zone which may be necessary to construct any physical barrier to enable acoustic attenuation to take place and to make the proposed residential areas (beyond this red line application boundary) suitable for use – in accordance with BS8233:2014 target noise levels. Once agreed and approved in writing by the Local Planning Authority, the applicant/developer shall implement in full any and all acoustic boundary treatments (if required by the approved scheme) prior to the commencement of use of any B2 or B8 uses hereby permitted

Reason: To protect residential amenity from adverse impacts on amenity through noise from proposed B2 and B8 uses in accordance with Policy QE6.”

“26 - ACOUSTIC ASSESSMENT AND MITIGATION – B2 AND B8 USES. Prior to the commencement of use of any B2 or B8 use on any individual plot or phase hereby permitted, the applicant shall submit, in writing, details of an acoustic assessment to address noise generation potential for that plot or phase on outline permitted residential development to the south of the red line boundary of the outline permission but also on the existing residential dwellings beyond Burtonwood Road. The acoustic assessment shall review in detail all proposed activities from general operations, from the use of plant or equipment and/or vehicular activities associated with the proposed use and shall also consider any acoustic mitigation offered by any acoustic barrier required separately or already in existence. Mitigation measures shall be proposed wherever the resultant noise levels will either exceed guideline BS8233:2014 values at residential plots or where a BS4142:2014 noise assessment indicates that rated noise levels may give an increased likelihood of complaints. Once agreed and approved and in any case prior to the commencement of use on any individual plot or phase, all agreed mitigation measures shall be implemented in full and shall be retained for the duration of that use.

Reason: To protect residential amenity from adverse impacts on amenity through noise from proposed B2 and B8 uses in accordance with Policy QE6.”


3.2 BRITISH STANDARDS AND GUIDANCE BS8233:2014: GUIDANCE ON SOUND INSULATION AND NOISE REDUCTION FOR BUILDINGS

3.2.1. BS8233 provides recommendations for the control of noise in and around buildings. It suggests appropriate criteria and limits for different situations, which are primarily intended to guide the design of new buildings, or refurbished buildings undergoing a change of use, rather than to assess the effect of changes in the external noise climate.

3.2.2. The guidance provided includes appropriate internal and external noise level criteria which are applicable to dwellings exposed to steady external noise sources. It is stated in the British Standard that it is desirable for internal ambient noise levels not to exceed the criteria set out in Table 1 below.

Table 1 – Summary of Internal Ambient Noise Level Criteria for Habitable Rooms in BS8233: 2014

Activity Location Period

07:00 to 23:00 hours i.e. daytime

23:00 to 07:00 hours i.e. night-time

Resting Living Room LAeq,16hr 35dB -

Dining Dining Room LAeq,16hr 40dB -

Sleeping (daytime resting)

Bedroom LAeq,16hr 35dB LAeq,8hr 30dB

3.2.3. For regular individual noise events with the potential to cause sleep disturbance it is stated that a guideline value may be set in terms of SEL or LAFmax. No further guidance is provided with respect to an appropriate criterion which may be adopted for the assessment of such events, however the previous (1999) version of BS8233 stated that “For a reasonable standard in bedrooms at night, individual noise events (measured with F time-weighting) should not normally exceed 45 dB LAmax”. This criterion is consistent with World Health Organisation Guidance.

3.2.4. Recommendations for design criteria for external areas are also provided, in this regard it is stated;

“For traditional external areas that are used for amenity space, such as gardens and patios, it is desirable that the external noise level does not exceed 50 dB LAeq,T, with an upper guideline value of 55 dB LAeq,T which would be acceptable in noisier environments. However, it is also recognized that these guideline values are not achievable in all circumstances where development might be desirable. In higher noise areas, such as city centres or urban areas adjoining the strategic transport network, a compromise between elevated noise levels and other factors, such as the convenience of living in these locations or making efficient use of land resources to ensure development needs can be met, might be warranted. In such a situation, development should be designed to achieve the lowest practicable levels in these external amenity spaces, but should not be prohibited”.


BS4142: 2014: METHODS FOR RATING AND ASSESSING INDUSTRIAL AND COMMERCIAL SOUND

3.2.5. BS4142 describes methods for assessing sound of an industrial and/or commercial nature, including sound from fixed installations (such as mechanical and electrical plant).

3.2.6. It provides a method of determining the ‘rating level’ for sources of industrial or commercial sound for the purposes of investigating noise impact, assessing sound from new, modified, or additional sources of sound, and assessing sound affecting new residential premises.

3.2.7. BS4142 uses several terms to define the various parameters / indicators used in assessments, including:

Specific sound – the commercial / industrial noise source under consideration; Residual sound – the sound level at the noise-sensitive receivers in the absence of the specific

sound; Ambient sound – the sound level at the noise-sensitive receivers in the presence of the specific

sound (i.e. ambient = residual + specific); Background sound level – the sound pressure level which is exceeded by the residual sound for

90% of the measurement period; and, Rating level – the specific sound, corrected for acoustically distinguishing characteristics.

3.2.8. BS4142 states it is normally possible to carry out a subjective assessment of characteristics, based on the following correction guidelines:

Tonality: +2 dB for a ‘just perceptible’ tone, +4 dB for a ‘clearly perceptible’ tone, and rising to +6 dB for a ‘highly perceptible’ tones;

Impulsivity (rapidity of change and overall change in level): +3 dB for ‘just perceptible’ impulsivity, +6 dB for ‘clearly perceptible’ impulsivity, rising to +9 dB for ‘highly perceptible’ impulsivity; and,

Intermittency: if the on/off-time of the specific sound is readily distinctive at the noise-sensitive receivers, +3 dB.

3.2.9. Typically, the greater the difference between the background and rating level, the greater the magnitude of impact, although BS4142 emphasises that this is highly context-specific.

3.2.10. BS4142 states that an initial estimate of the impact can be obtained by subtracting the background sound level from the rating level, and that:

Typically, the greater the difference the greater the magnitude of the impact; A difference of around +10 dB or more is likely to be indicative of significant adverse impact,

depending on context; A difference of around +5 dB or more is likely to be indicative of adverse impact, depending on

context; The lower the rating level relative to the background sound level, the less likely it is that the

specific sound will have an adverse impact, depending on context. Where the rating level does not exceed the background sound level, this in an indication that the specific sound will have a low impact, depending on context.

3.2.11. This initial estimate of impact can then be modified to take account of context, including reference to factors such as:

The absolute level of the sound;


The character and level of the residual sound compared to the character and level of the specific sound;

The sensitivity of the receptor and whether dwellings or other premises used for residuals purposes will already incorporate design measures that secure good internal and/or outdoor acoustic conditions, such as:

Façade insulation on treatment; Ventilation and/or cooling that will reduce the need to have windows open so as to provide

rapid or purge ventilation; and Acoustic screening.

3.2.12. It should be noted that BS4142:2014 has been subject to amendment, with the latest version now being BS4142:2014+A1: 2019. However, these amendments are not material to this assessment and it should be noted that planning condition 26 specifically references the use of BS4142:2014.


4 BASELINE NOISE SURVEY

4.1 PURPOSE 4.1.1. A baseline noise survey has been undertaken to establish the prevailing levels of noise at a location

selected as representative of the existing dwellings on the east side of Burtonwood Road.

4.2 TIMING AND DURATION 4.2.1. The survey commenced at 11:56 on Wednesday 26 June 2019, with the measurement continuing

continuously over an approximate six-day period, concluding at 09:24 the following Tuesday. The survey period therefore included several full weekdays and a full weekend period.

4.3 MEASUREMENT LOCATION 4.3.1. The measurement was undertaken on the eastern site boundary, at the bottom of the Burtonwood

Road embankment, such that it was subject to similar conditions as the closest existing dwellings east of Burtonwood Road. The approximate Ordnance Survey X-Y coordinates for the measurement location are: 357114 390996.

4.3.2. The measurement location was approximately 22m from the nearside curb edge of Burtonwood Road and was subject to free-field conditions, with the microphone elevated to 1.5m above local ground.

4.3.3. The measurement location was selected as being at similar distances from both Burtonwood Road and the M62 as the closest residential dwellings east of Burtonwood Road.

4.3.4. The measurement location is shown in Figure 1 above.

4.4 METEOROLOGICAL CONDITIONS 4.4.1. The weather conditions over the course of the baseline noise survey were ideal for environmental

noise measurement being dry and warm and wind conditions being still to light throughout.

4.4.2. Wind direction was generally easterly / south-easterly for first half of the survey changing to be northerly / westerly for the remainder of the survey. Wind speeds remained below 5m/s throughout.

4.5 MEASUREMENT EQUIPMENT AND CALIBRATION 4.5.1. The survey was carried out using the class 1 measurement equipment detailed in Table 2.

Table 2 – Measurement Equipment Details

Equipment Description Manufacturer & Type No. Serial No. Calibration Due Date Sound Level Meter 01 dB CUBE 10629

07 March 2020 Pre-amplifier Acoem PRE 22 10563

Microphone GRAS 40CD 161937

Calibrator 01 dB-Metravib CAL 21 34344462 27 September 2019

4.5.2. The measurement system had been calibrated to traceable standards within the previous 24 months, and the hand-held calibrator within the previous 12 months. The measurement system was


calibrated on site at the beginning and end of the survey period with the hand-held calibrator. No significant measurement drift arose.

4.6 MEASUREMENT RESULTS BACKGROUND SOUND LEVELS

4.6.1. The obtained measurement data have been analysed to determine representative values for the prevailing daytime and night-time background sound levels. This has included preparation of histograms to determine the most commonly occurring background sound levels during each period (daytime and night-time), and following the guidance in BS4142. The results of this analysis are presented in Appendix B and the selected representative background sound levels are duplicated in Table 3.

Table 3 - Daytime and Night-time Representative Background Sound Levels. Free-field, dB(A)

Daytime (07:00 to 23:00) Night-time (23:00 to 07:00) Selected Representative Background Sound Level 50 dB LA90,T 46 dB LA90,T


5 ASSESSMENT

5.1 NOISE MODEL 5.1.1. A detailed acoustic model of the site and surrounding area has been created to facilitate calculation

of operational noise levels from the Proposed Development.

5.1.2. The noise model has been generated using the CadnaA® noise modelling software.

5.1.3. The following methodology was adopted in the generation of the noise model:

The model was set to apply the prediction methodology set out in the ISO 9613-2. The model was set to include second order reflected noise from solid structures. Open source LiDAR 1m posting DTM topographic data was incorporated into the model for the

existing site and surrounding area, including Burtonwood Road and the M62. Within the site area, the LiDAR data was replaced with the ground contour model for the site, as

proposed. The topographic design of the recent Charon Way reconfiguration was incorporated into the

ground model, including the addition of the full length of the existing 2m acoustic fence. The Scheme layout plan was calibrated into the noise model based on Ordnance Survey six

figure grid references. The Scheme buildings were incorporated into the model, with acoustically reflective façades,

based on the Scheme layout plan, and with heights taken from the Scheme elevation drawings (18.6m unit height) as being submitted as part of the revered matters application.

Globally, ground absorption was set to G = 1 (100% acoustically absorbent ground) with proposed areas of hardstanding (e.g. car parking and service yards) included separately with ground absorption set to G=0 (100% acoustically reflective ground).

Existing dwellings east of Burtonwood Road were incorporated based on Ordnance Survey mapping, and with a height of 8m above local ground.

The operational service yard noise sources have been modelled and calibrated using WSPs in-house database of measured noise sources, as described further below and presented within Table 4.

HGVs arriving and departing each service yard have been incorporated as line sources extending from the redline site boundary into each of the three proposed service yards (beyond the redline site boundary, the access roads would be adopted highways). A source height of 0.5m above local ground has been used.

Line sources have also been included, along the same extents, for HGV trailer chillers, but with a source height of 3.5m above local ground.

HGV arrivals, manoeuvres, air breaks, loading and unloading, cab idling, and departures have been entered as point sources with a height of 0.5m for every proposed HGV docking bay.

Similar point sources have also been added for every HGV parking space (but without the loading and unloading element).

Idling trailer chillers have been added as point sources with a height of 3.5m. These point sources have been added for each and every HGV docking bay and proposed parking space.


SOURCE NOISE DATA

5.1.4. The source data presented in Table 5 has been adopted for service yard movements in and around the proposed service yard docking and parking bays. This data has been adopted from WSP’s library of in-house historic measurement data for similar facilities to that proposed.

Table 4 - HGV Movement and Static Chiller Data, Free-field, dB, Octaves Linear Activity Octave Band Centre Frequency Time (s) LAeq,T

@ 10m

LAFmax

@ 10m 63Hz 125Hz 250Hz 500Hz 1kHz 2kHz 4kHz 8kHz

HGV arriving and manoeuvring 71 66 65 66 69 65 58 50 109 72 78

Air brakes - - - - - - - - 3 80 81

HGV engine idling 75 58 66 60 62 59 52 42 37 66 -

Unloading activities - - - - - - - - 420 60 77

HGV pulling away 71 65 64 65 63 62 56 46 15 68 -

Electric powered HGV trailer chiller 75 71 67 61 58 56 52 45 continuous 65 -

Diesel powered HGV trailer chiller 82 78 74 68 65 63 59 52 continuous 72 -

5.1.5. For HGV movements to and from the service yards, source data has been determined based upon the guidance contained within the Noise Advisory Council (NAC) guide entitled: A guide to measurement and prediction of the equivalent continuous sound level Leq, a report by a Working party for the technical sub-committee of the Noise Advisory Council. This document states that it was prepared for use by practitioners with the appropriate technical background who need to measure or predict environmental noise. It presents general procedures to be followed for the measurement and prediction of Leq from a number of different sources.

5.1.6. Section 2.5 of the document details a method for calculating the Leq noise level from the combined effect of a number of events (e.g. HGV pass-bys) with their own single event noise exposure level (LAX, also commonly referenced as the SEL). The method is as follows:

Leq = LAX + 10log(n) -10Log(T)

Where:

LAX = single event noise exposure level of the event (SEL)

n = the number of events

T = the time in seconds

5.1.7. In addition, Fig 4.1.4 of the document presents a method for determining the LAX (SEL) at a distance of 10m from the nearside kerb edge, for heavy and light vehicles travelling at different speeds. This figure is duplicated in the diagram below:


5.1.8. Combining the use of NAC Figure 4.1.4 with the equation adopted from NAC Section 2.5 provides a

means of determining the Leq that will arise at 10m as a result of a given number of HGV movements on an access road, or along a defined path etc. This has been applied assuming a HGV pass-by speed of 30 km/hour. The sound power levels of the HGV line sources have then been calculated such that the calculated levels are modelled.

5.2 MODELLED SCENARIOS 5.2.1. The levels of noise that will be generated from the operation of the proposed units will depend upon

their future occupants. For example, the use of HGV trailer chillers would be limited to occupants requiring the storage and distribution of chilled foods. For other ‘ambient’ operators, the use of HGV trailer chillers would not be required.

5.2.2. At this stage, the future occupants of the development are not known. Consultation has therefore been undertaken with a leading operator of logistics and industrial property, to establish realistic operating scenarios for assessment.

5.2.3. The following scenarios have determined, where a ‘turnover’ includes 1 HGV arrival, 1 HGV manoeuvre, 1 air brakes activated, 1 cab engine idle and 30minutes of unloading / loading (docks only) and 1 HGV pulling away.

Scenario 1 (Ambient Goods)

25% of all docks and parking-bays subject to a turnover within the 1-hour assessment period (equivalent to 6 turnovers at every dock and bay every 24 hours).

No chilled food arrivals or departures (i.e. no trailer chillers). All docking bays subject to a turnover would have an associated access road HGV arrival and

departure movement (1 in and 1 out) within the 1-hour assessment period.

Scenario 2 (Chilled Goods – Electric Chillers)

As scenario 1, but with 30% of turnovers including electric powered trailer chillers.


Scenario 3 (Chilled Goods – Diesel Chillers)

As scenario 1, but with 30% of turnovers including diesel powered trailer chillers.

5.2.4. For scenarios 2 and 3 it has been assumed that good practice would be employed at Unit 2 with the western portion of this unit used for chilled goods, and the eastern portion dedicated to ambient goods.

5.2.5. It should be noted that commonly, the use of diesel-powered trailer chillers has been, or is being phased out in preference for quieter and more economical electric chillers, but the diesel scenario has been retained for completeness.

5.3 PREDICTED OPERATIONAL NOISE LEVELS RECEPTOR LEVELS

5.3.1. A sample of receptor locations have been selected for assessment, as shown in Figure 3 below. These include locations on the proposed residential development areas to the south (worst case positions have been selected aligned with the gaps between units) and a sample of the existing dwellings east of Burtonwood Road.

Figure 3 Adopted Dwelling Receptor Locations

Future 1 Future 1 Existing 1

Existing 5

Existing 2

Existing 3

Existing 4

Existing 6


5.3.2. For each Scenario, operational specific noise levels have been predicted at both ground floor (1.5m above ground) and first floor storey heights (4.0m above ground). The results of these predictions of presented in Table 5 below,

Table 5 – Predicted Receptor Specific Noise Levels (LAeq,T), dB

Receptor Reference

Height Scenario 1 (Ambient Goods)



Future 1 Ground 28 32 38

First 32 35 40


First 23 28 33

Existing 1 Ground 17 22 28

First 20 24 29


First 23 25 30


First 29 30 33


First 37 41 46


First 34 39 44


First 32 37 43

5.3.3. Table 6 presents the corresponding rating levels assuming a +3dB correction for impulsivity (all scenarios), and a +2dB correction for tonality (chilled scenarios).

Table 6 – Predicted Receptor Rating Noise Levels (LAr,Tr), dB

Receptor Reference





First 35 40 45


First 26 33 38


First 23 29 34


First 26 30 35



First 32 35 38


First 40 46 51


First 37 44 49


First 35 42 48

5.4 BS8233 ASSESSMENT 5.4.1. Condition 25 requires the resulting noise levels on proposed residential areas to the south are

suitable for use in accordance with BS8233.

5.4.2. These development areas are represented by the ‘Future 1’ and ‘Future 2’ receptor locations. The range of rating levels predicted at these receptors are 25 to 43 dB LAr,Tr at ground floor and 26 to 45 LAr,Tr at first floor heights.

5.4.3. These ground floor levels comply with the BS8233 criteria of 50-55dB for external amenity spaces, whilst a noise attenuation of between 0 and 8dB would be required by the building fabric to achieve the 35 / 40dB internal criterion for living rooms / dining rooms. This will be achieved under an open window scenario (for which a reduction of between 10 and 15dB is commonly recognised). Far greater attenuation than that required would be achieved under a closed window scenario.

5.4.4. The first floor levels would need to be attenuated by between 0 and 15 dB, in order to achieve the 30 dB internal criterion for bedrooms. Again, this could be easily achieved through building facade measures, with large parts of the residential development areas also retaining compliance under an open window situation.

5.4.5. It can therefore be concluded that due to the good practice deign measures that have been incorporated into the scheme layout design, no additional boundary treatments or set back distances are required.

5.5 BS4142 ASSESSMENT 5.5.1. Condition 26 requires that the resulting operational noise levels at existing dwellings to the east of

Burtonwood Road are assessed in accordance with BS4142.

5.5.2. These existing dwellings are represented by the ‘Existing 1’ to ‘Existing 6’ receptors. Table 7 below presents the difference between the representative daytime and night-time background noise levels taken from Table 3 and the operational rating levels taken from Table 6, in accordance with BS4142.

5.5.3. The BS4142 guidance is that a difference of around +5 dB or more is likely to be indicative of adverse impact, depending on context, and that where the rating level does not exceed the background sound level, this in an indication that the specific sound will have a low impact, depending on context.

5.5.4. The context in this case is that the existing dwellings are already subject to road traffic noise from Burtonwood Road, the M62, Charon Way and the M62 J8, whilst the source noise being assessed is


also similar, being vehicular in nature. It is also that the case that the closest dwellings to the proposed service yards were only recently built, and so would include modern building fabric appropriate to protect against the prevailing noise environment and proximity to Burtonwood Road and the M62 etc.

5.5.5. On this basis, a BS4142 assessment result of +3dB has been adopted as the test criterion. Results above this criterion are presented in bold text.

Table 7 – BS4142 Assessment – Existing Dwellings East of Burtonwood Road, dB

Receptor Reference




Existing 1 Ground -30 -23 -17

First -23 -17 -12


First -21 -16 -11


First -14 -11 -8


First -6 0 +5


First -9 -2 +3


First -11 -4 +2

5.5.6. It can be seen from Table 7 that this criterion is met, for all receptors for Scenario 1 (Ambient Goods) during both daytime and night-time operations. The rating levels for this scenario fall well below the adopted assessment criterion of +3dB in all cases.

5.5.7. Compliance is also identified for Scenario 2 (Chilled Goods – Electric Chillers) for all receptors during both daytime and night-time periods, by a margin of at least 3dB, and commonly much greater than this.

5.5.8. For scenario 3 (Chilled Goods – Diesel Chillers), compliance is also identified for all receptors for daytime operations, and all but one of the receptors during the night-time. For the single receptor, the adopted a +3dB assessment criterion is exceeded by 2dB.

5.5.9. Consideration has been given to mitigation measures in the following section.


6 MITIGATION

6.1 SUMMARY 6.1.1. The above assessment has identified that for realistic operating scenarios for the distribution of both

ambient goods and chilled foods (including use of electric powered HGV trailer chillers), appropriate assessment criteria are predicted to be met at existing dwellings east of Burtonwood Road. The adopted assessment criteria are predicted to be met by at least 3dB and commonly by much greater margins.

6.1.2. As noted above, the use of diesel-powered trailer chillers has, or is, commonly being phased out in preference for quieter and more economical electric chillers. It is therefore considered appropriate that the mitigation assessment should be based on the more realistic scenario of using electric chillers (Scenario 2). For this scenario the adopted assessment criteria are met so no additional acoustic mitigation is required.

6.1.3. Notwithstanding this, the applicant has agreed to the installation of a 2.5m acoustic fence at the top of the Burtonwood Road embankment, on the west side of this route (the side closest to the Unit 2 service area). This is proposed such that the adopted assessment criteria will be met by even greater margins and such that the potential for greater intensity of activities within the service yards is future proofed.

6.1.4. The alignment of the proposed additional 2.5m acoustic fence is presented in Figure 4 below.

Figure 4 Proposed Additional 2.5m Acoustic Fence Alignment:

Additional Proposed 2.5m Acoustic Fence

Existing 2m Acoustic Fence


6.1.5. The resulting updated BS4142 assessment results with this additional acoustic barrier in place are presented within Table 8 below.

Table 8 – BS4142 Assessment – Existing Dwellings East of Burtonwood Road – Including Additional Proposed 2.5m Acoustic Fence

Receptor Reference





First -23 -17 -12


First -21 -16 -11


First -18 -14 -9


First -10 -3 +3


First -11 -4 +2


First -13 -5 +1

6.1.6. It can be seen from Table 8 above that with the additional proposed 2.5m acoustic fence, compliance with adopted assessment criterion is achieved for all scenarios, including the use of diesel trailer chillers.

6.1.7. For the more realistic scenarios of ambient goods and chilled goods using electric chillers, the margin of compliance is increased to a minimum of 6dB at the closest receptor, with much greater degrees of compliance at other receptors.

6.1.8. The acoustic fence should be imperforate, continuous, sealed, with no holes of gaps, and have a minimum acoustic performance of category B2 according to BS EN 1793-2:1998: Road traffic noise reduction devices. Test method for determining the acoustic performance. Intrinsic characteristics of airborne sound insulation.


7 CONCLUSION

7.1.1. WSP has been appointed by Omega Warrington Limited to provide acoustic consultancy services to assist in the layout and design of a B2/B8 development proposed to form part of Omega Warrington. This appointment was made to ensure that good practice acoustic design and layout techniques were employed in the development of the scheme layout design, to minimise the potential for noise impact from the Proposed Development.

7.1.2. The development is proposed south of Skyline Drive and west of Burtonwood Road, with the plot benefiting from outline planning permission (planning reference 2017/30371). The redline boundary of the plot falls entirely within the Zone 1 and 2 areas of that outline permission.

7.1.3. WSP’s commission has included the provision of good practice acoustic design input to the Scheme design, as well as the noise impact assessment works necessary to ensure compliance with the requirements of noise related planning condition numbers 25 and 26 of the outline approval.

7.1.4. Conditions 25 and 26 require that in conjunction with any B2/B8 reserved matters application within Zone 1 of the outline approval, an assessment of noise from the proposed development is undertaken. The assessment is required to consider potential impact on permitted residential development to the south (with reference to BS8233:2014) and existing residential dwellings to the east, east of Burtonwood Road (with reference to BS4142:2014). It is required that, where the assessment determines that any additional acoustic screening as necessary, this is implemented in full prior to the commencement of use of the scheme.

7.1.5. In order to ensure that the potential for noise impact from the scheme is minimised, a number of good practice design measures have been employed in the development of the scheme layout, These measures have included the following:

All service yards are located on the north side of the proposed units, close to the M62 and Burtonwood Road, and are therefore in the parts of the site subject to the highest prevailing noise levels.

All service yard locations ensure a substantial minimum distance separation distance of 170m to proposed residential development areas to the south.

All service yards are fully screened from proposed residential development areas to the south by the proposed B2/B8 units themselves (which are proposed to be approximately 18.6m in height).

All service yards are fully screened from existing residential dwellings on the east side of Burtonwood Road, either by the proposed B2/B8 units themselves, or by the existing earthworks on which Burtonwood Road is located. This road is on a steep-sided, wide embankment next to the site, being approximately 5m above the ground level of the proposed Unit 2 service yard on one side and the existing dwellings on the other.

The acoustic performance of the above earthworks is further enhanced by the existing 2m high acoustic fence on the south side of Charon Way / east side of Burtonwood Road. This acoustic fence is located on the raised edge of the earthworks closest to the existing dwellings. In total, there is therefore an approximate 7m high acoustic screen between existing dwellings east of Burtonwood Road and the closest proposed service yards.

Unit 2 has been kept as far north as possible to ensure that the unit itself provides additional acoustic screening to as many dwellings on the east side of Burtonwood Road as possible.


The proposed finished ground levels of the service yards have been kept low (approximately at existing ground level) to retain maximum benefit from the 7m acoustic screen to the east of Unit 2.

Regardless of the above, there is a minimum separation distance of approximately 100m between existing dwellings east of Burtonwood Road and the closest proposed service yard (that of Unit 2), with Burtonwood Road and associated embankment and acoustic fence in-between.

7.1.6. Notwithstanding all of the above best practice noise mitigation measures that have been employed in the development of the Scheme layout design, an assessment of potential noise impact has been undertaken for compliance with Conditions 25 and 26.

7.1.7. To inform the completed assessment, a detailed baseline noise survey has been undertaken to establish the prevailing ambient and background noise levels in the vicinity of existing dwellings east of Burtonwood Road.

7.1.8. A detailed noise level prediction exercise has then been undertaken for the Scheme, facilitated by the completion of a detailed noise modelling exercise. The noise modelling results have been assessed with reference to both BS8233 and BS4142 as required by conditions 25 and 26.

7.1.9. It has been identified that at land to the south of the proposed development, operational noise levels would be sufficiently low to facilitate residential development, when assessed with reference to BS8233.

7.1.10. It has also been identified that when considering both ambient goods and chilled food distribution using HGV trailers with electric powered chillers, the good practice design measures that have been employed in the scheme layout are sufficient to appropriately control operational noise levels at existing dwellings east of Burtonwood Road when assessed in accordance with BS4142.

7.1.11. Notwithstanding this, the applicant has agreed to the installation of a 2.5m acoustic fence at the top of the Burtonwood Road Embankment, on the west side of this route (closest to the Unit 2 service area). This is proposed such that the adopted assessment criteria will be met by even greater margins and such that the potential for greater intensity of activities within the service yards is future proofed. It has also been identified that this additional measure will also ensure sufficient noise attenuation to protect against the unlikely scenario of the use of diesel powered trailer chillers across the proposed scheme.

Confidential

GLOSSARY OF ACOUSTIC TERMINOLOGY

ZONES 1 AND 2 - STORAGE AND DISTRIBUTION WSP Project No.: 70063279/001 | Our Ref No.: August 2019 Omega Warrington Limited

NOISE Noise is defined as unwanted sound. Human ears are able to respond to sound in the frequency range 20 Hz (deep bass) to 20,000 Hz (high treble) and over the audible range of 0 dB (the threshold of perception) to 140 dB (the threshold of pain). The ear does not respond equally to different frequencies of the same magnitude, but is more responsive to mid-frequencies than to lower or higher frequencies. To quantify noise in a manner that approximates the response of the human ear, a weighting mechanism is used. This reduces the importance of lower and higher frequencies, in a similar manner to the human ear.

Furthermore, the perception of noise may be determined by a number of other factors, which may not necessarily be acoustic. In general, the impact of noise depends upon its level, the margin by which it exceeds the background sound level, its character and its variation over a given period of time. In some cases, the time of day and other acoustic features such as tonality or impulsiveness may be important, as may the disposition of the affected individual. Any assessment of noise should give due consideration to all of these factors when assessing the significance of a noise source.

The most widely used weighting mechanism that best corresponds to the response of the human ear is the ‘A’-weighting scale. This is widely used for environmental noise measurement, and the levels are denoted as dB(A) or LAeq, LA90 etc., according to the parameter being measured.

The decibel scale is logarithmic rather than linear, and hence a 3 dB increase in sound level represents a doubling of the sound energy present. Judgement of sound is subjective, but as a general guide a 10 dB(A) increase can be taken to represent a doubling of loudness, whilst an increase in the order of 3 dB(A) is generally regarded as the minimum difference needed to perceive a change under normal listening conditions.


Acoustic Terminology

dB (decibel) A unit of level derived from the logarithm of the ratio between the value of a quantity and a reference value and the scale on which sound pressure level is expressed. Sound pressure level is defined as 20 times the logarithm of the ratio between the root-mean-square pressure of the sound field and a reference pressure (2x10-5 Pa).

dB(A) A-weighted decibel. This is a measure of the overall level of sound across the audible spectrum with a frequency weighting (i.e. ‘A’ weighting) to compensate for the varying sensitivity of the human ear to sound at different frequencies.

LAeq,T LAeq is defined as the notional steady sound level which, over a stated period of time (T), would contain the same amount of acoustical energy as the A-weighted fluctuating sound measured over that period.

LAmax LAmax is the maximum A-weighted sound pressure level measured over the period stated. LAmax is sometimes used in assessing environmental noise where occasional loud noises occur, which may have little effect on the overall LAeq noise level but will still affect the noise environment. Unless described otherwise, it is measured using the 'fast' time weighting.

L10 & L90 If a non-steady noise is to be described it is necessary to know both its level and the degree of fluctuation. The Ln indices are used for this purpose, and the term refers to the level exceeded for n% of the time. Hence L10 is the level exceeded for 10% of the time and as such can be regarded as the 'average maximum level'. Similarly, L90 is the ‘average minimum level’ and is often used to describe the background noise. It is common practice to use the L10 index to describe traffic noise.

Fast A time weighting with a 125 millisecond time constant

Slow A time weighting with a 1000 millisecond time constant.

Free-field Level

A sound field determined at a point away from reflective surfaces other than the ground with no significant contributions due to sound from other reflective surfaces. Generally as measured outside and away from buildings.

Façade Level A sound field determined at a distance of 1 m in front of a large sound reflecting object such as a building façade.

Ambient Sound

The all-encompassing noise level measured in LAeq,T. The Ambient Noise Level incorporates background sounds as well as the industrial source noise under consideration.


Residual Sound

The Ambient Noise Level in the absence of the industrial source noise under consideration, measured in LAeq,T.

Specific Sound

The noise level measured in LAeq,T attributed to the industrial noise source under consideration alone.

Background Sound Level

The noise level in the absence of the industrial source noise under consideration, measured in LA90.

Confidential

MEASUREMENT DATA ANALYSIS


BACKGROUND SOUND LEVEL DATA ANALYSIS Graph B1 - Measurement Location 1 - Daytime (07:00 - 23:00) – LA90,1hour Histogram

Graph B2 - Measurement Location 1 - Night-time (23:00 - 07:00) - LA90,15minute Histogram


Results Summary

Table B1 – Daytime and Night-time Background Sound Levels

Noise Index / Indicator Daytime (07:00 to 23:00) Night-time (23:00 to 07:00)

Maximum LA90,T1 60 60

Minimum LA90,T1 45 37

Log Average LA90,T1 54 49

Linear Average LA90,T1 52 46

Most Commonly Occurring LA90,T1 50 47

Log Average Period LA90,T2 52 46

Linear Average Period LA90,T2 50 44

Selected Representative value 50 46

1 T = 1 hour for the daytime and 15 minutes for the night-time 2 T = 16 hours for the daytime and 8 hours for the night-time

For the daytime period, the represented background sound level has been selected as 50dB(A). This is 10 dB lower than the maximum value and 5dB higher than the minimum. It is also lower that both the log and linear average values whilst being the same as the most commonly occurring value and the linear average period value.

For the night-time period, the representative background sound level has been selected as 46dB(A). This is 14 dB lower than the maximum value and 9dB higher than the minimum. It is also lower than the log average and the most commonly occurring value whilst being equal to linear average and the log average period values.

CONFIDENTIAL

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ZONES 1 AND 2 - STORAGE AND DISTRIBUTION