Turitea Transmission Line Construction Noise Management Plan

Prepared for:

4Sight Consulting

Date:

12 July 2019

Title:

Turitea Windfarm Construction Noise Management Plan

Revision Number:

3

Prepared by: Kelly Leemeyer, MASNZ Consultant

Reviewed by: Jon Styles Director and Principal

Construction Noise Management Plan prepared by Styles Group for 4Sight Consulting.

Revision history Rev

Date

Comments

Version

1

08.07.19

Draft for comment

Draft

2

08.07.19

Updated following comments

1

3

12.07.19

Updated following further comments

2

Prepared by

Reviewed by

Kelly Leemeyer

Jon Styles

Consultant

Director and Principal

Kelly Leemeyer

Jon Styles

Consultant

Director and Principal

Kelly Leemeyer

Jon Styles

Consultant

Director and Principal

Table of Contents 1.

Introduction ....................................................................................................... 4

2.

Contacts ........................................................................................................... 4

3.

Scope of Transmission Line Works ................................................................... 4

4.

Construction methodology ................................................................................ 5

5.

Project Conditions ............................................................................................. 5

6.

Duration of Works and Hours of Construction ................................................... 6

7.

Project Noise Limits .......................................................................................... 6

8.

Special Construction Activities .......................................................................... 7

9.

Potentially Affected Properties .......................................................................... 8

10.

Community Liaison ........................................................................................... 8

11.

Likely Noise Emissions ..................................................................................... 9

12.

Noise Mitigation Measures .............................................................................. 10

13.

Monitoring & Reporting ................................................................................... 11

14.

Corrective Action Measures ............................................................................ 12

15.

General Requirements .................................................................................... 14

Appendix A: Glossary of Acoustical Terms ................................................................. 15 Appendix B: The Construction Site ............................................................................. 16 Appendix C: 70 dB LAeq noise contour for helicopter use ............................................ 17 Appendix D: Noise Monitoring Form ........................................................................... 18

1.

Introduction

4Sight Consulting has engaged Styles Group to prepare a Construction Noise Management Plan (CNMP) for the construction and installation of a new 12km long 220kV transmission line to connect Transpower’s existing Linton Substation to the “Plantation Substation” at Mercury’s Turitea Wind Farm (the Project), near Palmerston North.

The project site is located approximately 10 kilometres south-east of Palmerston North primarily along a 14 kilometre ridge in the northern Tararua Ranges. The project is located within the Turitea Reserve (owned by Palmerston North City Council (the PNCC)) and on adjoining private farmland.

The project will include use of helicopters to string transmission lines and to transport towers and equipment to some sites where access is difficult due to the topography in the area.

This CNMP has been prepared in accordance with Schedule 3 of project’s consent condition 15 and with reference to Appendix E of NZS 6803:1999 Acoustics - Construction noise. It is designed to ensure appropriate management of noise effects during the construction period. It has been prepared based on the specific construction plant and methodologies for this project and with respect to the specific receiving environment.

This CNMP is a ‘living document’ that will be updated as the works progress and if changes become necessary to adopt the best practicable option to reduce noise emissions. A glossary of the acoustical terms used in this document is provided as Appendix A. 2.

Contacts

The contact for queries, comments or complaints regarding the project, and the manager responsible for implementing this CNMP is: Emma Comrie-Thomson

Electrix Environmental Manager (consultant)

Ph: 021 755509 The consultant engaged to provide construction noise monitoring and advice is: Styles Group Acoustics & Vibration Consultants 3.

Ph: 09 308 9015

Scope of Transmission Line Works

This CNMP relates to the environmental effects associated with the construction of a new 12km long 220kV transmission line to connect Transpower’s existing Linton Substation to the “Plantation Substation” at Mercury’s Turitea Wind Farm, near Palmerston North.

The following works will be undertaken during the construction phase of the project: 

Installation of double circuit transmission line structures, including a mixture of steel tubular monopoles and steel lattice towers complete with concrete foundations, anticlimb devices and signage; 4



Two circuits to be strung with simplex Sulfur All Aluminium Alloy Conductor, complete with all insulators, fittings, conductor hardware, and vibration dampers;



Two composite fibre-optic ground wires, complete with fittings, junction boxes and hardware and vibration dampers;



Duplicate 220kV line protection schemes for circuit 1 end to end inclusive of the required protection communications;



Access tracks for construction and future maintenance of the line and structures; and



Vegetation removal and trimming.

Access to the site will be from 241 Kahuterawa Road, 132 Greens Road, 131 Greens Road and 146 Harts Road (Transpower Property – Linton Substation).

The closest receiver to any of the towers or construction works is 145 Harts Road, which is 270 m from towers 1 – 3. This is a light commercial/industrial premise (C-Dax Agricultural Solutions). All other receivers are over 400 m from the nearest construction works or tower.

The closest receiver to the take off / landing area for the helicopter is 762 Kahuterewa Road, which is 1.1 km away. The closest receiver to a tower requiring the helicopter is 166 Greens Road, which is approximately 950 m from tower 20. All other towers requiring the helicopter are within the Turitea Reserve and over 1.5 km from the nearest receivers.

4.

Construction methodology

Works will be undertaken using the following plant: 

Excavators



Bulldozers



Cranes



Trucks / truck and trailer units



Concrete trucks and pumps



Concrete batching



A Helicopter



Polaris 1000XP with Prospector Pro tracking system



Hand held tools



Drill Rig

5.

Project Conditions

The relevant consent conditions for the construction phase of the project are set out below.

Please refer to Section 6 of this CNMP for interpretation of the construction noise limits with respect to the working hours and receiving sites.

5

6.

14.

Noise from all construction work shall be measured and assessed in accordance with NZS 6803, and shall comply with the noise limits for long-term duration set out in that Standard

15.

A CNMP shall be prepared prior to the commencement of any construction works and shall be properly implemented at all times. The CNMP shall be generally in accordance with section 8 and the relevant annexures of NZS6803, which detail the relevant types of construction to which the CNMP is to apply, and procedures that will be carried out to ensure compliance with that Standard.

16.

The CNMP shall be prepared by an appropriately qualified and experienced acoustic consultant, and shall be submitted to the Environmental Compliance Managers of each respective Council for review, acting in a technical certification capacity. A response should be provided within 30 working days of receipt. Construction activities must not commence until written certification has been obtained.

Duration of Works and Hours of Construction

Construction works will take up to approximately 12 months to complete and are scheduled to begin in August 2019.

Works will generally be undertaken between the hours of 07:30 to 18:00, Monday to Saturday.

In the summer months, construction works (with the exception of helicopter use) may begin at 06:30 and finish at 19:00, Monday to Saturday.

On occasion and in consultation with affected landowners, works may occur on a Sunday (except helicopter use), however these works are restricted by Schedule 3 of the project’s consent condition 63 for certain access points.

7.

Project Noise Limits

This section sets out the noise performance criteria for the project which includes long-term construction activities in residential and rural zones.

Applicable Noise Performance Criteria In accordance with Condition 14 of the conditions for the project, construction noise shall comply with the following noise limits in Table 7.1: Table 7.1 Construction noise limits Time of week

Weekdays

Time period

Maximum noise level (dBA) Leq

LMax

6:30am - 7:30am

55

75

7:30am - 6:00pm

70

85

6:00pm - 8:00pm

65

80

8:00pm - 6:30am

45

75

6

Time of week

Saturdays

Sundays and public holidays

Time period

Maximum noise level (dBA) Leq

LMax

6:30am - 7:30am

45

75

7:30am - 6:00pm

70

85

6:00pm – 8:00pm

45

75

8:00pm – 06:30am

45

75

6:30am - 7:30am

45

75

7:30am - 6:00pm

55

85

6:00pm – 8:00pm

45

75

8:00pm – 06:30am

45

75

All noise levels will be measured and assessed in accordance with the New Zealand construction noise Standard NZS 6803:1999 Acoustics – Construction Noise. The noise limits are applicable at 1 m from the most exposed facade of any occupied building where the construction noise is being measured and assessed. The noise limits do not apply at a building (or the affected part of it) that is not occupied during the works.

If an assessment of the noise levels within a building is required, the noise will be measured with reference to Clause 6.2.2 of NZS 6803:1999 and the provisions of NZS 6801:2008 Acoustics – Measurement of environmental sound. This section requires that noise levels inside a building must be at least 20 dB lower than the noise limits in the above Table (and therefore Condition 14 of the consent).

In addition to the project conditions, there is the overarching requirement to comply with section 16 of the Resource Management Act. Section 16 (1) of the Act states: Duty to avoid unreasonable noise - Every occupier of land (including any premises and any costal marine area), and every person carrying out an activity in, on, or under a water body or the costal marine area, shall adopt the best practicable option to ensure that the emission of noise from that land or water does not exceed a reasonable level.

The best practicable option (BPO) is defined by the Act as: best practicable option, in relation to a discharge of a contaminant or an emission of noise, means the best method for preventing or minimising the adverse effects on the environment having regard, among other things, to a) the nature of the discharge or emission and the sensitivity of the receiving environment to adverse effects; and b) the financial implications, and the effects on the environment, of that option when compared with other options; and c) the current state of technical knowledge and the likelihood that the option can be successfully applied.

8.

Special Construction Activities 7

This section sets out the construction activities requiring special noise management or mitigation measures.

Helicopter use A helicopter will be used to lower materials to towers within Turitea Reserve and for Tower 20.

The towers within Turitea Reserve and tower 20 are at least 900 m from any receivers.

Use of helicopters will only be during the daytime.

9.

Potentially Affected Properties

The properties potentially affected by construction noise are generally those within 50 m of any works. Additionally, properties within 200 m of the helicopter flight path will also potentially be affected by construction noise.

Table 9.1 sets out the closest receivers to the towers. Any tower not listed in Table 9.1 is further than 400 m from any receivers.

Table 12.1 details the reference noise levels at 10 m for activities on site, along with the minimum compliance distance between the noise source and 1 m from the faรงade of any occupied building.

Towers 30 - 44 are located within the Turitea Reserve and do not have any receivers within 500 m.

Table 9.1 Noise receivers and proximity to closest tower Address

Distance to closest tower

Closest towers

145 Harts Road, Turitea

260 m

1, 2, 3

305 Kahuterewa Road

> 400 m

8, 9

307 Kahuterewa Road

> 400 m

10

307 Ngahere Park Road

> 400 m

11

133 Greens Road

> 250 m

12, 13, 14, 15

166 Greens Road

> 150 m

16, 17, 18

Potential noise emissions are discussed in Section 11 Likely Noise Emissions. The separation distances detailed in Section 11 will be used to identify the potentially affected properties at each stage of the works and physical mitigation will be used where required (and practicable) to allow compliance with the project limits.

10. Community Liaison Works for the project will be managed under the Community Liaison Group. Prior to works commencing on site all receivers within 400 m of works will be informed of the following information by letter drop: 8



A brief overview of the works, including details of helicopter use



The expected start date of works



The expected duration of works



The days and hours of the week when works may be undertaken (including possible contingency days)



The noise mitigation to be implemented



The availability of noise monitoring to address any concerns



Contact details for the receipt of any noise complaints or concerns.

A complaints register will be kept and maintained on site to record the details of any noise complaints received and the action taken in response to the complaint.

In addition, the overall Mercury Project has community notifications being circulated via: 

Mailing lists; and



Website updates.

Prior to helicopter use, both Mercury and Electrix will reengage with affected property owners and detail points above.

11. Likely Noise Emissions Table 11.1 details the reference noise levels at 10 m for activities on site, along with the minimum compliance distance between the noise source and 1 m from the façade of any occupied building. The minimum distances must be observed for the noise limits to be complied with.

The calculations assume 100% operating time for the plant during any 15 minute sample.

Table 11.1 is provided as a guide and can be updated when measurements of the site specific equipment are undertaken.

Table 11.1: Separation distances for works

Activity on site

Reference noise level at 10 m from plant

Minimum compliance distance between noise source and 1 m from facade of occupied dwelling (unmitigated)

40 t excavator

79 dB LAeq

38 m

30 t excavator

75 dB LAeq

24 m

22 t excavator

71 dB LAeq

15 m

100 t mobile crane lifting load

71 dB LAeq

15 m

400 t mobile crane lifting load

78 dB LAeq

34 m

28 t dozer

79 dB LAeq

38 m

9

Activity on site

Reference noise level at 10 m from plant

Minimum compliance distance between noise source and 1 m from facade of occupied dwelling (unmitigated)

Truck and trailer

66 dB LAeq

9m

82 dB LAeq

54 m

Angle grinder

80 dB LAeq

43 m

Concrete pump and truck discharging

67 dB LAeq

10 m

Generator

66 dB LAeq

9m

Concrete batching

70 dB LAeq

14 m

Drill Rig

80 dB LAeq

43 m

Concrete cutter (low noise saw blade)

Where it is predicted or measured that any activity will exceed the noise limits for the project, Section 12 and 14 of this CNMP will be referred to and mitigation implemented wherever practicable to reduce the noise effects at the nearest occupied sites.

Styles Group has used Brüel & Kjær Predictor computer noise modelling software to predict the noise levels from the operation of the helicopter, based on the International Standard ISO 9613-1/2. The Brüel & Kjær Predictor software is globally recognised and has been successfully implemented on a large number of projects throughout New Zealand.

The results of the noise modelling show that use of the helicopter for tower 20 and towers 30 44 (on Turitea Reserve) will comply with the daytime noise limits at all times.

Helicopter use must be limited to between the hours of 0730 to 1800 on weekdays and Saturdays only.

The noise contours for helicopter take off / landing, and use for tower 20 are shown in Appendix C. 12. Noise Mitigation Measures The contractor will take all practicable steps to reduce the noise associated with the works by implementing the general noise mitigation measures listed below: Control at Source 

Where possible, the quietest machinery and methods available and practicable will be used.



All machinery will be either new or in good condition upon its arrival at the site, and will thereafter be maintained in good condition throughout the entire duration of the project.

10

For example, all saw blades will be kept sharp, and all tracked plant will be greased to reduce squeaking 

Upon arrival at the site, the machinery and plant will be checked to ensure that it is not generating unnecessary noise and rectified if necessary



When selecting any plant such as compressors, generators or pumps for use on the project, the degree of noise generation between models will be considered as a major factor



When machinery or plant is not required to be running, it should be switched off and not left idling (where appropriate)



Noisy plant and machinery should be strategically positioned on the site to reduce the effects on neighbours where practicable e.g. away from the site boundaries and using structures or plant on site as screening



Where practicable, all plant and equipment shall utilise broadband reverse alarms in place of traditional pure tone ‘beepers’



The tail gates of trucks must be closed with care and not slammed (where possible) or allowed to fall closed causing unnecessary noise



Horns shall not be used excessively unless in the case of an emergency



Any radios or music played on site must be inaudible at the neighbouring sites



All workers shall be familiar with the provisions of this CNMP and made aware of the impacts of noise and the above methods that can be used to minimise noise emissions. The key provisions in the CNMP are part of the Electrix Environmental Induction.

Acoustic Screening Due to the significant separation distances available on this project, specific acoustic screening is not anticipated to be required. However, temporary acoustic screening will be constructed around the works area if any construction works are required within the minimum unmitigated compliance distance (column 3) listed in Table 11.1.

To be acoustically effective, all screening must be no less than 2.0 m in height and have a surface density of no less than 10 kg/m2 with no gaps along the length of the barrier or between the barrier and the ground.

13. Monitoring & Reporting Noise monitoring will be performed: 

If, in the opinion of the Site Manager or Council (or their representatives), the noise from any activity on the site appears excessive; or



Following the receipt of any reasonable noise complaint.

The results of the monitoring will be used to determine what, if any, further mitigation is required following comparison with the relevant noise limit(s). The results will be used to 11

update and maintain this CNMP to ensure that minimum compliance distances and mitigation measures are specifically tailored to the equipment used on site. The results of all monitoring will be retained and made available to Palmerston North City Council and / or Tararua District Council at their reasonable request.

Any non-compliance with the noise limits will be addressed by following the corrective action measures in Section 14 of this CNMP and reducing noise levels with reference to Section 12.

A noise monitoring form is attached as Appendix D. Measurements will be undertaken in accordance with this document and by observing the following requirements: 

All noise measurements will be undertaken using a sound level meter conforming to at least IEC651 Type 2 criteria



All noise measurements and assessments will be carried out in accordance with NZS 6803:1999 Acoustics - Construction Noise



All noise monitoring and assessment will be undertaken by a suitably qualified and experienced person.

14. Corrective Action Measures Should noise measurements undertaken by Palmerston North City Council and / or Tararua District Council (or its representative) or the consent holder identify non-compliance with the limits set out in this CNMP, the following corrective action measures will be followed. The process is illustrated by Figure 14.1. i.

The activity responsible for the exceedance will cease when practicable and only if safe to do so.

ii.

Further mitigation options will be investigated. Where practicable mitigation measures are available, these will be implemented and step (iii) followed.

iii.

Monitoring will be undertaken to confirm the performance of the mitigation measures

iv.

If non-compliance is identified, including the further mitigation measures implemented, the process will be repeated from step (i) to include any further practicable mitigation options.

12

Undertake attended noise monitoring (Section 14):  In response to a reasonable complaint.  Noise from construction activity is deemed excessive by site manager or Council  To test mitigation implemented.

Yes

Do the measured levels exceed the project limits?

Cease works if practicable Notify Site Manager and implement corrective action measures (Section 14).

No Review mitigation and management strategies to reduce noise emissions.

Update CNMP where required. Liaise with Site Manager, Council and stakeholders where appropriate.

No

Can noise limits practicably be met with implementation of mitigation methods?

Yes

Implement mitigation methods.

Figure 14.1: Process for corrective action measures

13

15. General Requirements This CNMP is intended to be a ‘living’ document. It will be updated throughout the works as site and plant specific noise data is obtained. A copy of the CNMP must be kept at the work site for the duration of the works.

All personnel should be informed about the need to reduce noise and about the effects and hazards of excessive noise. As part of their training, special attention should be given to: 

Proper selection, use and maintenance of tools, machinery and related noise control devices



Positioning of machinery on site



Avoidance of unnecessary noise



Procedures for receiving, referral and investigation of noise complaints.

14

Appendix A: Glossary of Acoustical Terms

Acoustical term Noise

dB (decibel)

A-weighting

LAeq(t)

LAmax NZS 6803:1999

CNMP

Definition A sound that is undesired by, or distracting to, the recipient.

The basic measurement unit of sound. The logarithmic unit used to describe the ratio between the measured sound pressure level and a reference level of 20 micropascals (0 dB).

A frequency filter applied to the full audio range (20 Hz to 20 kHz) to approximate the response of the human ear at lower sound pressure levels.

The A-weighted equivalent sound pressure level with the same energy content as the measured varying acoustic signal over a sample period (t). The preferred metric for sound levels that vary over time because it takes into account the total sound energy over the time period of interest.

The maximum A-weighted sound pressure level recorded during the measurement period.

New Zealand Standard NZS 6803:1999 Acoustics – Construction noise.

Construction noise management plan. A document to assist with the appropriate management of noise during construction works.

15

Appendix B: The Construction Site The area of the project is shown in Figure B.1 below.

The location of towers and piles are identified by number.

Figure B.1: The construction site

16

Appendix C: 70 dB LAeq noise contour for helicopter use The flight path for the helicopter from take off to Tower 20 is shown in Figure C.1 below (red dotted line). The green line shows the 70 dB LAeq contour for this flight path.

Figure C.1: 70 dB LAeq noise contour for helicopter use, Tower 20

17

Appendix D: Noise Monitoring Form Name:

Date:

Notes for noise monitoring All sections of this form must be completed when undertaking construction noise measurements for the project. Please provide a sketch of the area, sound sources and measurement position on the rear of this form.

Valid measurements cannot be undertaken in persistent rain or in wind speeds greater than 5 m/s.

Measurements are to be undertaken at 1 m from the faรงade of the receiving building most exposed to the sound under investigation, and 1.2 m to 1.5 m above the relevant floor level. No adjustment to the measured level is to be made for reflected sound from the faรงade. If measurements must be undertaken at a proxy location then adjustments to the measured level may be required to correct for distance and faรงade reflections (+3 dB).

Sound source and instrumentation Location of works Description of construction activity being monitored Measurement instrumentation (type and serial number) Date of most recent laboratory calibration Field calibration check (time and adjustment)

Meteorological conditions Cloud cover (Octas) Rain Wind speed and direction

Methodology Location/orientation of microphone Height of microphone above ground and distance to faรงade of receiving building Distance between microphone and sound source Ground conditions between sound source and microphone Any barriers or objects between sound source and microphone Distance to any reflective surfaces other than receiving faรงade Extraneous noise sources

18

Measurement results Sample

Duration of

LAeq

LAmax

Sound sources controlling

start time

sample

(dB)

(dB)

the measured levels

Adjustments required for distance, faรงade correction or barriers

Do the measurements show full compliance with the project noise limits?

Yes:

The measurement results shall be used to update the site specific noise levels and construction separation distances within the CNMP.

No:

The CNMP shall be referred to for the appropriate corrective action measures and further noise mitigation options.

19