C4 10 Ruru Street SSCNVMP

C4

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10 Ruru Street SSCNVMP

C4.1 Introduction

This Site Specific Construction Noise and Vibration Management Plan (SSCNVMP) is for the residential building located at 10 Ruru Street. It is reproduced from the Mt Eden Enabling Works CNV DWP, where construction was predicted to exceed the standards in CRL designation conditions 31 and 32. A SSCNVMP is not required for the Mt Eden Station Main Works. It is included for information to ensure consistency across project stages. This SSCNVMP has been prepared in accordance with CRL designation conditions 37 and 38 and is Appendix C4 of the Mt Eden Main Works Construction Noise and Vibration Delivery Work Plan (CNV DWP). It is a supplementary document that builds on the CNV DWP, and therefore directly references relevant sections of the CNV DWP to avoid repetition. The objective of this SSCNVMP is to detail the best practicable option(s) (BPO) to avoid, remedy or mitigate the identified adverse effects from noise and/or vibration exceedances at 10 Ruru Street.

This SSCNVMP has been prepared for the Link Alliance and forms part of the Construction Environmental Management Plan (CEMP) for the Mt Eden Station Main Works.

C4.2 Engagement

Mt Eden Enabling Works (for information)

Link Alliance representatives Sonya Leahy, Thibaut L'Hopital, Aidan Kirkby-McLeod, Duncan Whyte and Craig Fitzgerald met with site representatives Dr Helen Gaeta and Megan Ottley on 4 September 2019. The matters discussed included:

An overview of the project General programme, demolition, piling, rock breaking/blasting and tunnelling activities

Overview of the CNV DWP and this SSCNMP, communications triggers and protocol The basement level fronting Nikau St is a storage business and car park (activities are not considered noise sensitive), above which double level townhouses (noise sensitive when occupied) encircle a common courtyard area. Figure B.5 in Appendix B of the Mt Eden Enabling Works CNV DWP shows that the south façade is predicted to be exposed to noise levels between 75 –80 dB L Aeq during the closest rock breaking activities, exceeding the 75 dB L Aeq noise limit. Activity specific mitigation and management measures are included in Section 9 of the CNV DWP and not repeated here (e.g. Section 9.7 concrete and rock breaking). The townhouses have linear weatherboard façades with operable glazing and a steel pitched roof. The estimated sound level difference across the façade with the windows and doors closed is 30 decibels. The predicted construction noise effects from Table 12-1 in Section 12.1 are predicted to be typically acceptable, but with the potential for some disturbance in the southern most apartments during the closest rock breaking works. Physical receiver mitigation, such as temporary relocation of affected receivers, alternative ventilation and façade sound insulation improvements, have been considered, but are not required as part of the BPO for the C3 enabling works. Preliminary blasting vibration level predictions (Section 6.3 of the Enabling Works CNV DWP) identify that there is potential to exceed the residential cosmetic building damage

Mt Eden Main Works CNV DWP –Appendix C SSCNVMPs

thresholds. Cosmetic building damage effects are deemed ‘minor damage’ in the DIN Standard (Section 5.2), such as cracking in paint or plasterwork, and can generally be easily repaired. A pre-construction building condition survey has been undertaken accordance with CRL designation condition 46 to ensure any damage is identified for remediation. This is the same process implemented for the previous C6 blasting works on the corner of Nikau and Ruru Streets.

Dr Gaeta and Ms Ottley agreed that prior communication of timeframes for works with the potential to exceed the relevant noise limits was an acceptable means of managing effects. No further activity specific consultation is necessary over and above regular communication (Section 10).

Mt Eden Main Works

None required for the Mt Eden Station Main Works. However, noting Dr Gaeta and Ms Ottley previously agreed that prior communication of timeframes for works with the potential to exceed the relevant noise limits was an acceptable means of managing effects. No further activity specific consultation is necessary over and above regular communication (Section 10).

C4.3 Review Process

If Dr Gaeta and Ms Ottley or affected site representatives request consultation in the future, this SSCNVMP will be updated in accordance with CRL designation conditions 37.5 and 38.5, with consideration given to the following:

The extent to which noise may exceed the designation standards

The timing and duration of any exceedance

The type of activity causing any exceedance

A summary of the communication and consultation with the receiver

The methods and measures to mitigate effects

A statement of why they reflect best practicable option Communications records are contained in the communication and consultation plan (CCP). This SSCNVMP will be updated to summarise engagement and any agreed site-specific measures.

Page 22 Mt Eden Main Works CNV DWP –Appendix C SSCNVMPs