Industrial and Trade Activities Environmental Management Plan

Mt Eden Main Works Industrial and Trade Activities Environmental Management Plan

CRL- MTE-RME- LKA- PLN-800043

Revision: 001 Date: 29 June 2020

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Industrial and Trade Activities Environmental Management Plan

Industrial and Trade Activities Environmental Management Plan CRL-MTE-RME-LKA-PLN-800043 This document is uncontrolled when printed. This document should be printed in colour

Revision Status Revision

Date

Version details

Prepared By

Approved By

Rev A00

20 April 2020

Draft for Auckland Council and Independent Peer Review

R. Van de Munckhof

-

Rev 000

16 June 2020

Final for pre-lodgement

R. Van de Munckhof

Peter Roan

Rev 001

29 June 2020

Final for submission

R. Van de Munckhof

Peter Roan

Approval Status Name/Title

Signature

Date

Prepared by:

R. Van de Munckhof Discipline Manager Environmental Engineer

29 June 2020

Approved by:

Peter Roan Link Alliance – Consenting Lead

29 June 2020

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Industrial and Trade Activities Environmental Management Plan

Table of contents 1. Introduction ............................................................................................. 5 1.1

Overview of CRL Works in Mt Eden ................................................................................ 5

1.2

ITA EMP Staging ............................................................................................................ 6

1.3

Purpose of this ITA EMP ................................................................................................ 6

1.4

Relevant Conditions ...................................................................................................... 7

1.5

Sustainability .............................................................................................................. 12

1.6

ITA EMP Review and Updates ...................................................................................... 12

1.7

ITA EMP Author........................................................................................................... 13

2. Mt Eden Main Works Description .......................................................... 14 2.1

Overview of Works ...................................................................................................... 14

2.2

Tunnel Boring Machine Support Operations ................................................................. 20

2.3

Bentonite Plant ........................................................................................................... 20

2.4

D-wall Construction ..................................................................................................... 24

2.5

Soil Mixing Plant and Ground Improvement Works ...................................................... 24

3. Industrial and Trade Activities................................................................ 26 4. Site Drainage ......................................................................................... 31 5. Management Procedures and Mitigation Measures ............................... 33 5.1

Bentonite Plant ........................................................................................................... 33

5.2

D-Wall Construction .................................................................................................... 33

5.3

Soil Mixing Plant ......................................................................................................... 33

5.4

Ground Improvement.................................................................................................. 34

5.5

TBM Component A Plant ............................................................................................. 34

5.6

Tunnel Segment Storage .............................................................................................. 34

5.7

Muck Bin Area............................................................................................................. 35

5.8

Diesel Tank and Generator .......................................................................................... 35

5.9

Stormwater and Groundwater Treatment .................................................................... 35

5.10 Environmentally Hazardous Substance Management ................................................... 36 5.11 Waste Management .................................................................................................... 36 5.12 Wash-down................................................................................................................. 37

6. Spill Response ........................................................................................ 38 7. Discharge Monitoring and Reporting ..................................................... 39 Page 3

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Industrial and Trade Activities Environmental Management Plan 7.1

Monitoring.................................................................................................................. 39

7.2

Reporting .................................................................................................................... 39

8. Environmental Compliance Management and Review ........................... 40 8.1

Site Inspections ........................................................................................................... 40

8.2

Environmental Audits .................................................................................................. 40

8.3

Non-Conformance, Corrective and Preventative Action ................................................ 40

9. Training.................................................................................................. 41 9.1

Employees and Subcontractors .................................................................................... 41

Appendix A: ISCA Requirements .................................................................. 42 Appendix B: General Emergency Spill Response Plan ................................... 44 Appendix C: Bentonite Plant Spill Response Plan ......................................... 46 Appendix D: Jet Grout Plant Emergency Response Plan ............................... 49 Appendix E: Record of CLG and Auckland Council Comments ....................... 50 E1. CLG Comments ................................................................................................................ 50 E2. Auckland Council Comments ............................................................................................ 50 E3. Mana Whenua ................................................................................................................. 53

Appendix F:

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Register of Plan Updates ...................................................... 54

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Industrial and Trade Activities Environmental Management Plan

1.

Introduction

The City Rail Link (CRL) project comprises the construction, operation and maintenance of a 3.4 km underground passenger railway, running between Britomart Station and the North Auckland Rail Line (NAL) near Mt Eden Station. The CRL also involves the construction of two new underground stations at Aotea and Karangahape and a redeveloped Mt Eden Station (refer to Figure 1-1). The design and construction of the CRL infrastructure between Aotea and Mt Eden Stations is being delivered by the Link Alliance.

Figure 1-1: CRL Route and Location

This Industrial and Trade Activities Environmental Management Plan (ITA EMP) has been prepared in relation to the Mt Eden Main Works (“main works”).

1.1 Overview of CRL Works in Mt Eden CRL works in the Mt Eden area involve the construction of the southern section of the tunnel structures and the tie-in of the CRL railway to the existing NAL, including the construction of the redeveloped Mt Eden Station. The Mt Eden Active Construction Zone (ACZ) and Construction Support Areas (CSAs) are generally located between Nikau Street to the north, State Highway 1 (SH1) to the east, Dominion Road to the west and the existing NAL to the south.

The works in this area include: • • •

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Operational activity required to support the tunnel boring machine (TBM) drive, including control room and plant, storage and spoil handling; Construction of a new Mt Eden Station building, incorporating passenger linkages between the new CRL platform and the modified existing NAL platform; Road-over-rail bridges at Mt Eden Road, Normanby Road and Ruru Street with sections of road realignment;

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Industrial and Trade Activities Environmental Management Plan •

• • • •

Grade separation structures for the existing and new rail lines to pass-over and connect with each other, including the Newton Junction Grade Separation Structure, the Eastern Facing Connection and the Western Facing Connection; Construction of a portal vent house building structure; Installation of retaining walls and utilities; Pedestrian and cyclist bridges at Fenton Street and Porters Avenue; and New road linkages within the reinstated area, post-construction.

Given the nature and scale of CRL construction works in Mt Eden, works are being undertaken in a staged manner, involving: • •

•

Enabling and early works (demolition, network utility relocation and site establishment work) – early works have commenced and will continue to the end of 2020; Main construction works (construction of the underground CRL cut-and-cover tunnels, grade separation structures and trenches, station building and platforms, and tie-ins to the NAL) to commence mid-2020 through to mid-2023; and Public realm reinstatement – likely to be undertaken from 2021 to early 2024.

1.2 ITA EMP Staging To reflect the staged construction approach for the CRL in the Mt Eden area, a series of EMPs are being prepared.

This ITA EMP addresses the main works, which are detailed in the Construction Environmental Management Plan (CEMP) and summarised in Section 2 of this ITA EMP.

1.3 Purpose of this ITA EMP This ITA EMP has been prepared to manage adverse effects relating to industrial and trade activities (ITAs) required during the main works, including portal construction, tunnel boring, bulk excavation, diaphragm wall (D-wall) construction, piling, site establishment works and associated storage and handling of hazardous substances. Specifically, the purpose of the EMP is to identify those activities to be undertaken that may result in contamination of land and/or stormwater, and to document the procedures to be implemented to appropriately manage these risks.

The ITA EMP outlines the following: •

Identification of ITAs to be undertaken during the main works that may result in contamination of land and/or water;

•

Identification of potential contaminants associated with these activities;

•

The methods to be used to prevent identified contaminants from contacting with stormwater runoff and methods to manage environmental risks from on-site activities;

•

An appropriate monitoring and auditing programme to ensure site performance is undertaken in accordance with this ITA EMP; and

• Staff training.

This ITA EMP addresses the requirements of the CRL resource consent conditions 159 – 179 (discharge permit R/REG/2016/1898) and will be implemented throughout the construction period.

This ITA EMP forms part of the CEMP for the main works.

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Industrial and Trade Activities Environmental Management Plan A number of related management plans are referenced throughout this ITA EMP to avoid duplication of information and thereby enable efficient document control. The other relevant plans include: •

Construction and Environmental Management Plan (CEMP)

•

Erosion and Sediment Control Plan (ESCP)

•

Flocculant Treatment Management Plan (FTMP)

•

Emergency Spill Response Plan (ESRP) (Appendix B of this ITAEMP)

•

Bentonite Plant Spill Response Plan (Appendix C of this ITAEMP)

• Jet Grout Plant Emergency Response Plan (JGPERP)(Appendix D of this ITAEMP).

This ITA EMP has been prepared in consultation with the CRL Mana Whenua Forum and the Mt Eden Community and Business Liaison Group. A record of the consultation outcomes, including the Link Alliance’s response to matters raised, is included in Appendix E.

1.4 Relevant Conditions Table 1-1 identifies the resource consent conditions relevant to this ITA EMP and where they are addressed in the document.

Table 1-1: Resource consent conditions and location in Plan

Condition No.

Condition

Relevant section of this Plan

159

At least 20 working days prior to the commencement of construction, a final Industrial and Trade Activities Environmental Management Plan (EMP) shall be submitted to the Council (Team Leader Central Monitoring) for certification.

This document

160

The Consent Holder shall request the Council’s (Team Leader Central Monitoring) determination as to whether the EMP can be certified, in writing, within 10 working days following receipt of the EMP.

To be certified.

161

The EMP shall be prepared by a Senior Qualified Person and shall include, but not be limited to, the following:

Section1.7

a) identification of the specific activities conducted on the site;

Section 2

b) the identification of potential contaminants associated with these activities;

Section 3

c) methods used to prevent identified contaminants contacting stormwater runoff as far as practicable and methods to manage environmental risks from site activities;

Section 4

d) an Emergency Spill Response Plan (which includes the provision that all spills over 20 litres, or any spill of Environmentally Hazardous Substances that has entered the stormwater system, a water-body or has contacted unsealed ground, shall be reported immediately to the Auckland Council’s 24-Hour Pollution Hotline (09-377-3107));

Appendix B of this ITA EMP

e) an up-to-date and accurate site drainage plan showing the location of all site catch pits and the final discharge point(s) of the site stormwater system;

Included in the ESCP to avoid duplication.

f) an appropriate auditing programme to ensure all components of the site’s EMP are implemented;

Section 8.2

g) methods for providing and recording staff training; and

Section 9

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Condition No.

Condition

Relevant section of this Plan

h) a monitoring programme as outlined in Conditions 173 and 174.

Section 7.1

162

The Consent Holder shall ensure that the CSAs and ACZs are operated and managed in accordance with the certified EMP to ensure the risks from the site are managed appropriately.

Section 8.1

163

The Consent Holder shall ensure that a copy of the Council certified EMP is kept on site and accessible at all times.

Section 1.3

164

Following any change to the EMP, the Consent Holder shall submit details of the change to the Council (Team Leader Central Monitoring) for certification and request that the Council’s (Team Leader Central Monitoring) written determination as to whether the change can be certified to be provided within 10 working days of submission of the change.

Section 1.6

165

The EMP shall be reviewed and updated annually from the date of granting of this consent, to ensure all components of the EMP remain relevant.

Section 1.6

166

The Industrial Trade and Activity area for each of the Construction Support Areas shall not exceed the following:

Mt Eden works relate to CSA4 and CSA5 only, see Section 3

167

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CSA

Exposed Area Not to Exceed (m2)

1

25,000

2

9,000

3

9,000

4

36,000

5

6,500

In the event that any CSA requires an increase in area, the following information shall be provided to the Team Leader – Central Monitoring whose certification shall be requested prior to implementation: a) Plans and drawings outlining the details of the modifications; and b) Supporting information that confirms how the proposal does not affect the capacity or performance of the existing structural and procedural controls.

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No increase in area is proposed.

Industrial and Trade Activities Environmental Management Plan

Condition No.

Condition

Relevant section of this Plan

168

The Consent Holder shall ensure that the following structural controls are constructed for the following catchment areas and design standards and they are completed prior to discharges commencing from the site:

Settlement tanks and inlet protection described in the ESCP (Appendix H of the CEMP) Bunding of environmentally hazardous substances addressed in Section 5.9 of this ITA EMP

Works /controls

Device catchment area

Design requirements

2 x Settlement Tanks located on CSA 4

Activity area of grout plant (400m2), and segment storage yard (2660m2) on CSA 4

Settlement Tanks sizing to be based on 2% of the contributing catchment

Inlet protection measures

On all catch pits within CSA areas

Design in accordance with Auckland Council Best Management Practice: Catch pit Protection Area (AC 2011).

2 x Settlement Tanks located in CSA 1, CSA 2, CSA 3, CSA 4 and CSA 5

All Active Construction Zones (ACZ)

Settlement Tank sizing to be based on 2% of the contributing catchment

Bunding of Environmentally Hazardous Substances

As required

110% largest container

169

In the event that any minor modifications to the structural system are required, the following information shall be provided to the Team Leader – Central Monitoring whose certification shall be requested prior to implementation: a) Plans and drawings outlining the details of the modifications; and b) Supporting information that confirms how the proposal does not affect the capacity or performance of stormwater management system.

If any minor modification to the structural systems, these will be outlined in the ESCP.

170

Within 30 days of implementation, As-Built certification and plans of the stormwater management works, certified (signed) by a suitably qualified registered surveyor or a Chartered Professional Engineer as a true record of the stormwater management system, shall be provided to the Team Leader – Central Monitoring.

Section 5.1 of the CEMP

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Condition No.

Condition

Relevant section of this Plan

171

The As-Built plans shall include, but not be limited to: a) The surveyed location (to the nearest 0.1m) of the discharge points, with co-ordinates expressed in terms of NZTM and LINZ datum; b) Location, dimensions and levels of any major overland flow paths including cross sections and long sections; c) Plans and cross sections of all stormwater management devices, including confirmation of the Water Quality Volume, storage volumes and levels of any outflow control structure d) Documentation of any discrepancies between the design plans and the As-Built plans.

Detail is located in Section 5.1 of the CEMP

172

A meeting shall be held on site after the implementation of structural controls and the provision of As-Built documentation, and prior to the commencement of construction activities at each of the CSA/ACZs. The meeting shall include representation from the Team Leader Central Monitoring and the site stormwater engineer/contractors who have undertaken the work and shall confirm compliance with the relevant consent conditions.

Section 5.1 of the CEMP

173

Within 30 days of the installation of the water treatment systems, and prior to operation, the Consent Holder shall develop and submit to the Council (Team Leader Central Monitoring) for certification a discharge monitoring programme.

FTMP Section 8 (Appendix H of the CEMP)

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Industrial and Trade Activities Environmental Management Plan

Condition No.

Condition

Relevant section of this Plan

174

The water quality monitoring programme shall include, but not be limited to: a) Sampling locations (to include the final discharge from the treatment system located in CSA 1, CSA 2, CSA 3, CSA 5 and CSA 4); b) Methods and procedures for discharge sampling; and c) Monitoring parameters for analysis, which shall include: Daily − Water clarity (black disc) cm − Turbidity (NTU) − pH Weekly (in addition to the above) − Total Suspended Solids g/m3 − Total recoverable copper g/m3 − Dissolved copper g/m3 − Total recoverable zinc g/m3 − Dissolved zinc g/m3 − Total petroleum hydrocarbons g/m3 − Ammoniacal nitrogen* g/m3 − Nitrate nitrogen* g/m3 *only in discharge from treatment systems in CSA 3 and CSA 4 d) identified trigger levels for each of the above parameters. These trigger levels shall be developed with reference to the ANZECC Guidelines for water quality where applicable; and e) the methods and procedures for investigating and reporting stormwater discharge monitoring results to the Council (Team Leader Central Monitoring).

The sampling at the outlets from the work areas is outlined in FTMP Section 8 (Appendix H of the CEMP).

175

The discharge monitoring programme shall be implemented upon completion of works set out in Condition 168.

FTMP Section 8 (Appendix H of the CEMP)

176

Within five working days of receipt of sample results showing contaminants exceeding the agreed trigger levels in Condition 174(d): a) An investigation shall be undertaken to determine why exceedances were detected and to identify any additional source controls or treatment required; and b) The results of the investigation shall be reported to the Council (Team Leader Central Monitoring).

FTMP Section 8.5.2 (Appendix H of the CEMP)

177

Within eight weeks following the start of the monitoring required by Condition 173 a monitoring report shall be submitted to the Council (Team Leader Central Monitoring). The monitoring report shall include, but not be limited to, the following: a) a summary of the monitoring results to date; b) an interpretation of those results and suggestions for improvement to the site operations; c) a programme for ongoing monitoring including the reporting of results; and d) a programme for the ongoing maintenance of the discharge water management and treatment system.

FTMP Section 8.5.1 (Appendix H of the CEMP)

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Industrial and Trade Activities Environmental Management Plan

Condition No.

Condition

Relevant section of this Plan

178

For the duration of the construction stages of the Project, the Consent Holder shall forward a report annually from the date of granting of this consent to the Council (Team Leader Central Monitoring) evaluating the site’s environmental performance for the year to date.

Section 6 of the CEMP and Section 1.6 of this ITA EMP

179

The Annual Report required by Condition 178 shall include but not be limited to: a) all aspects of the performance of the EMP relating to this consent; b) a summary of all revisions and revised sections of the EMP; c) details of all inspections and maintenance of the stormwater system for the preceding 12 months; d) details of and changes to the person(s) or body responsible for the maintenance of site and the organisational structure supporting this process; e) results and analysis of the preceding 12 months of stormwater monitoring, along with an interpretation of those results and suggestions for improvement to the site operations; and f) records of any spills or incidents which occurred within the previous 12 months and the response which was undertaken.

Section 6 of the CEMP and Section 1.6 of this ITA EMP

1.5 Sustainability The Link Alliance is seeking an Infrastructure Sustainability Council of Australia (ISCA) Infrastructure Sustainability (IS) rating for the CRL project. Further details can be found in the main works CEMP and Sustainability Management Plan. Sustainability requirements that relate directly to this ITA EMP are included in Appendix A. These requirements are imbedded within the Delivery Work Plans and Management Plans for the main works to ensure that sustainability is a key focus and ‘the way we do things’.

In some cases, the IS requirements and sustainability goals enhance the designation and consent requirements.

1.6 ITA EMP Review and Updates This ITA EMP is a live document that will be reviewed at least annually, or as a result of a material change to the main works, or to address unforeseen adverse environmental effects arising from construction, or unresolved complaints. Any proposed changes to this ITA EMP must be certified by Auckland Council prior to any on-site activity reliant upon the change commencing. Refer to Section 6 of the CEMP for further detail on the review and updating process.

An annual report will be prepared and provided to Auckland Council in accordance with resource consent conditions 178 and 179, to include: a. all aspects of the performance of the EMP relating to this consent; b. a summary of all revisions and revised sections of the EMP; c. details of all inspections and maintenance of the stormwater system for the preceding 12 months; Page 12

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Industrial and Trade Activities Environmental Management Plan d. details of and changes to the person(s) or body responsible for the maintenance of site and the organisational structure supporting this process; e. results and analysis of the preceding 12 months of stormwater monitoring, along with an interpretation of those results and suggestions for improvement to the site operations; and f. records of any spills or incidents which occurred within the previous 12 months and the response which was undertaken.

1.7 ITA EMP Author This ITA EMP has been prepared by Rob Van de Munckhof with support from other T+T environmental engineering staff on behalf of the Link Alliance. Rob holds a chemical engineering degree and has over 18 years’ experience in environmental management and has experience in Industrial and Trade Activity assessment and management. He has undertaken assessments of surface water discharges from a range of industrial sites and is experienced in undertaking risk assessments to identify priority contaminants. He is experienced in the development of environmental management plans and surface water monitoring plans.

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2.

Mt Eden Main Works Description 2.1 Overview of Works

The main works involve construction along several active work fronts concurrently within the Mt Eden area at any one time, to enable the redevelopment of Mt Eden Station and establish the CRL tie-ins to the NAL. Works will be carried out in a staged fashion. The construction staging and methodologies are described in greater detail in the CEMP. Within the main works area, there are already other works occurring in accordance with the Mt Eden Enabling Works (OPW60350039) and Normanby Road Early Works (OPW60351423) outline plan packages.

This ITA EMP has been prepared to address the entire main works area including works in the CRL and KiwiRail designations as outlined in Figure 2.1.

CRL Designation 2500-6 KiwiRail Designation 6300

Figure 2.1 Site and Extent of main works

In summary, the main works involve: • •

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Ground improvements, in the form of deep soil mixing (contiguous piling and grout injection), within the NAL corridor between Mt Eden Road Bridge and Normanby Road; Bulk excavations and construction of retaining walls along the NAL to provide for the rail trenches and installation of new tracks. The excavation will encounter basalt, which will be removed via rock-breaking and blasting. In places, softer ground conditions are anticipated to be encountered, which may require the use of sheet piles; | Mt Eden Main Works

Industrial and Trade Activities Environmental Management Plan • • • • • •

Construction of the eastern and western crossover structures that enable the CRL rail lines to tie-in to the NAL; Construction of the Porters Avenue and Fenton Street pedestrian and cyclist bridges.

Construction of the Normanby Road grade separation bridge, including regrading of Normanby Road and realigning the Boston Road roundabout; Redevelopment of the existing NAL platform; Construction of the CRL platform and the foundations and building structures for the Mt Eden Station building and the ventilation building; and Operation of the TBM, including the conveying of spoil material from the tunnels and the refuelling and general maintenance of the TBM within CSA 4.

This ITA EMP has been prepared to address cumulative effects where the enabling, early and main works overlap each other..

The main construction works are described in detail in the CEMP. The works will utilise two construction support areas (CSAs), namely CSA 4 at the Mt Eden Station location, and CSA 5 at the Normanby Road location.

There are a number of activities to be located at each CSA that are identified in this ITA EMP as high risk to stormwater and which will require management to mitigate the risk. These sources can be categorised as mobile throughout the works, or as fixed activities, and in either case controls will be identified to appropriately manage the risk.

CSA 4 will be used to support the Mt Eden Station construction and the tunnel boring operations.

CSA 4 provides for tunnel segment storage, a spoil storage building, and site offices, as well as activities located within an area nominally referred to as the Technical Area adjacent to Shaddock Street. The Technical Area within CSA 4 will include a cooling plant, a bentonite plant, chemical storage areas, a water treatment plant, a tunnelling grout plant, workshops, air compressor units, and electrical transformers.

CSA 5 will be used to support the ground improvement works and other construction works at the Normanby Road end of the main works area, described in detail in the CEMP. The key plant and equipment supporting the works include a bentonite plant (during Stage 1), a soil mixing plant, muck bin for temporary spoil storage and a water treatment plant.

Site plans showing the site layouts and activities at CSA4 and CSA5 are shown in Figures 2-2 to 2-5.

The key ITA activities at each CSA are described in more detail in the following subsections.

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Figure 2-2 CSA 4 Site Layout and Activities Page 16 | Mt Eden Main Works

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Figure 2-3 CSA 4 Technical Area – Site Layout and Activities Page 17

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Figure 2-4 CSA 5 Stage 1 Layout Page 18

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Figure 2-5 CSA 5 Stage 2 Layout Page 19

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2.2 Tunnel Boring Machine Support Operations The tunnel boring machine (TBM) will be launched from the Mt Eden CSA 4 area and travel approximately 2 kilometres to the Aotea station. Tunnelling support operations taking place within CSA 4 are outlined in Table 2.1 below. As the TBM progresses underground, precast concrete lining segments are applied to the tunnel interior using a grout which will be batched on the surface at CSA 4, in a grout batching plant.

The final grout mix comprises of an “A component” consisting of cement, bentonite, water and a “B component” consisting of Sodium Silicate Accelerator. The B component will be stored in the TBM Technical area in 1 m3 intermediate bulk containers (IBC’s) and will be transported to the TBM using Multi Service Vehicles (MSV’s).

Table 2.1:

Tunnelling Support Operations

Material Storage

• Cement powder, pulverised fly ash and bentonite will be delivered to the plant by trucks. Each material will be pumped to dedicated storage silo through hoses. Dust filters on the silos will be used to control dust emissions.

• Bunded containers of sodium silicate, grease, oil and ground conditioning foam will be stored in the Chemical Storage Area of the Technical Area.

Tunnelling materials preparation

• Raw materials from the A Component will travel to the mixer via a closed screw conveyor. The conveyor will have a protective cover to control dust.

• The raw materials and additives will be mixed intermittently with water in the required proportions and the grout will then be stored in a tank.

• Transport of IBCs or drums of substances to the TBM

Tunnelling grout application

• Grout prepared in the grout plant will travel via pipe to the TBM and be pumped behind the tunnel linings to fill the annulus gap.

Spoil Disposal

• The spoil removed by the TBM will be comprised of grout, water and soil, and will be carried by a covered conveyor out of the tunnel to the covered spoil store at the southern end of CSA 4 adjacent to the western railway line.

• It will be unloaded by excavators to the building and reloaded as required into trucks for authorised offsite disposal.

Management of Discharges

• The TBM grout plant will be bunded within the Technical Area.

• Any surface water collected in the bunded area will be pumped to the water treatment plant located within the Technical Area for removal of sediment, oil and treatment for pH prior to discharge to stormwater if it meets the required standards or to trade waste. There will be no gravity discharge of any water from the bunded area to the stormwater system.

• Any spilt material pumped to the water treatment plant will be treated as per other sediment laden water on-site, with discharge to stormwater only occurring once the minimum water quality standards are met.

2.3 Bentonite Plant The D-wall construction as part of Stage 1 works requires the establishment of a bentonite plant at CSA 5 adjacent to Water Street. The bentonite plant will be located within a bunded area that drains to the water treatment plant. The purpose of the plant is to mix and recycle bentonite slurry associated with the D-wall construction. The plant comprises the following elements: Bentonite plant: Page 20

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Industrial and Trade Activities Environmental Management Plan •

Silos required for the storage of bentonite slurry for excavations;

•

Silos for the storage of bentonite slurry for disposal;

•

Bentonite mixer;

• Bentonite storage bags.

Bentonite treatment plant: •

Slurry Treatment Plant (STP) / De-sanding Unit - with a capacity of approximately 450 m3;

• Excavator.

The bentonite plant operation is outlined in Table 2.2 and is shown on Figure 2.6.

Table 2.2:

Bentonite Plant Operation

Bentonite Storage

• Storage of bentonite powder and slurry within silos

Bentonite Mixing and Recycling

• Mixing of bentonite with water and additives (sodium bicarbonate and bentocryl) to make a bentonite slurry, which will be temporarily stored within the silos before being used in the piling and D-wall construction operations. The bentonite mixer will be covered to control bentonite powder dust emissions.

• Transfer of the bentonite slurry to the storage silo, which is connected to the circuit of the STP / de-sanding unit and down to the D-wall operations via pipes and hoses.

• Slurry will be pumped out from the trench and travel back to the de-sanding unit / STP, where it will be treated to remove solids and recover the slurry for re-use.

Spoil Disposal

• Dry material recovered from the de-sanding unit will be removed off-site.

• Liquid spent slurry following de-sanding will be discharged into a bunded temporary spoil pit (approximately 24 m3) to be located on site. The spoil will be excavated and transported via trucks (approximately 3-5 per day) to an approved disposal facility.

Management of Discharges

• The entire bentonite plant area will be bunded to contain any spilt material or bentonite slurry in the event of a pipe or pump failure during transfer of the slurry, as shown in Figure 2..

• Any surface water collected in the bunded area will likely be disposed offsite (refer section 2.7.7 of the CEMP).

• Any spilt material pumped to the sediment control system will be treated as per other sediment laden water on-site, with discharge only occurring once the minimum water quality standards are met.

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Figure 2.6: Bentonite Slurry Operation

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Industrial and Trade Activities Environmental Management Plan A picture of the bentonite plant in place during the CRL Contract 1 construction works in lower Queen Street is provided in Figure 2.7 below to demonstrate the proposed bunding arrangement.

Figure 2.7: Bentonite Plant within Bunded area at CRL Construction Site in Lower Queen Street Page 23

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2.4 D-wall Construction D-walls are constructed using a Hydrofraise cutter and will be used to establish the sides of the trench excavation for the railway tracks.

The Hydrofraise cutter performs excavation using bentonite slurry to stabilise the trench. The slurry is pumped out and travels back to the bentonite plant’s de-sanding unit, where it is treated to remove solids and recover the slurry for re-use – as described in Section 2.3 above. Following excavation comes the reinforcement stage, where spoil is progressively mucked away and reinforcement cages are inserted along with staged concrete pouring.

Excavated spoil from D-wall construction is stockpiled at the spoil pit adjacent to the site entrance off Water Street for CSA 5 prior to removal off site.

2.5 Soil Mixing Plant and Ground Improvement Works There will be one soil mixing plant in place at CSA 5 only. The plant was established at the location shown in Figure 2.4 during the Normanby Road Early Works. The soil mixing plant will comprise the following elements: •

Generator;

•

Control room;

•

Chemical storage;

•

80 tonne horizontal silo for cement powder storage; and

• Mixer (approximately 6m3).

The soil mixing plant combines water and cement and additional additives to create a slurry mix for in situ-ground stabilisation in the Active Construction Zone (ACZ). The ground stabilisation involves insertion of a large diameter auger into the ground while grout is injected through ports in the tooling. The injected grout is mixed using paddles on the auger that mix the ground and grout as it progresses down a column. Spoil generated during the deep soil mixing is collected and transported to the muck bin. The soil mixing plant operation is described further in Table 2.3 Table 2.3:

Soil Mixing Plant Operation

Material Storage

• Cement powder will be delivered to the plant by trucks. It will be pumped to the storage silo through hoses. Dust filters on the silos will be used to control dust emissions.

Soil Mixing

• Cement powder will travel to the mixer via a closed screw conveyor.

• Cement powder will be mixed intermittently with water in the required proportions and the grout will then be stored in a tank.

In-situ ground stabilisation :

• Grout will travel via hoses, filters and pumps to the pump, then to the soil mixing auger where it will be injected into the soil to form a soil-cement mix in situ.

Spoil Disposal

• The resulting sludge (made of grout, water and soil) will be pumped from the ground improvement works location to the muck bin at the north-eastern end of CSA 5.

• It will be mucked out onto trucks for transport to a suitable facility.

Management of Discharges

• The soil mixing plant is contained in a bunded area.

• Any surface water collected in the bunded area will be pumped to the water treatment plant located near the CSA 5 site entrance off Water Street, for removal of sediment

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Industrial and Trade Activities Environmental Management Plan and treatment for pH prior to discharge. There will be no gravity discharge of any water from the bunded area to the stormwater system. • Any spilt material pumped to the water treatment plant will be treated as per other sediment laden water on-site with discharge to stormwater only occurring once the minimum water quality standards are met.

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Industrial and Trade Activities Environmental Management Plan

3.

Industrial and Trade Activities

The main industrial and trade related activities to be undertaken for the main works are outlined in Table 3.1. This table also outlines the potential contaminants associated with the activities and the relevant procedural and physical controls to be implemented during the works to minimise any adverse environmental effects. For completeness, the table has included both industrial and trade activities as well as general construction activities to ensure all activities with potential for either sediment generation and contaminants are collectively identified.

For the purposes of this ITA EMP, the main ITA activities are predominantly undertaken within CSA 4 and CSA 5. The maximum size of CSA 4 is 36,000 m2 and CSA 5 is 6,500 m2 which is consistent with resource condition 166.

References to procedural controls (including related plans/registers) are also provided in Table 3.1.

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Table 3.1: Summary of ITA Activities, General Site Activities, Potential Contaminants and Controls Contaminants

Initial risk

Procedural controls

Physical controls

Residual risk (with controls in place)

Hazardous substances store

Hydrocarbons, oils and greases, fuels, cement

High

• Risk register • Site induction and staff training

• All chemicals shall be stored within a bunded enclosure, such as a modified shipping container.

Medium

Water treatment

pH, sediment

High

• • • •

• Water treatment chemicals shall be stored within a bunded enclosure.

• Treatment tank size and pump rates to be set to allow required residence time and additional containment of any peak flows or over flows to be provided.

• Engineering controls in place to prevent overfill.

Medium

Tunnel segment storage

Sediment, pH

High

• Risk register • ESCP • FTMP

• Segment storage area drains to a low point where runoff can be contained to be pumped to the water treatment plant in the Technical Area of CSA 4.

Low

Grout mixing plant for tunnelling

Sediment, pH

High

• Risk register • JGPERP

• The grout mixing plant for Component A of the tunnelling grout shall be located within a bunded area draining to the containerised pH dosing system with pH and sediment monitoring undertaken.

Low

Activity Industrial and Trade Activities

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Risk register ESRP FTMP Site induction and staff training

Activity

Contaminants

Initial risk

Procedural controls

Physical controls

Residual risk (with controls in place)

Bentonite production (storage silo, mixer, pumps)

Sediment, Sodium bicarbonate and bentocyrl

High

• • • • •

Risk register BPSRP ESCP FTMP Site induction and staff training

• The bentonite silos and mixing units shall be located within a bunded area, or area draining to the WTP with sediment monitoring undertaken.

Low

Soil mixing plant (cement storage silo, mixer, pumps)

Sediment, pH

High

• • • • •

Risk register ESRP ESCP FTMP Site induction and staff training

• The cement silos and grout mixing units shall be located within a bunded area, or area draining to the WTP with sediment monitoring undertaken.

Low

Concrete pouring

Sediment, pH

High

• • • • •

Risk register ESRP ESCP FTMP Site induction and staff training

• No washing out of concrete trucks shall be undertaken on-site.

• All runoff from the site construction and excavation areas shall be directed to the WTP and containerised pH dosing system with pH monitoring undertaken.

Low

General site activities

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Activity

Contaminants

Initial risk

Procedural controls

Physical controls

Residual risk (with controls in place)

Handling and temporary storage of excavated or backfill materials

Sediment

Moderate

• • • •

Risk register ESCP FTMP Site induction and staff training

• Excavated material to be loaded directly onto truck or placed within designated stockpile areas for removal from site.

• Stockpile areas covered to prevent rainwater contact or located within a bunded area to divert sediment laden water to the WTP and containerised pH dosing system with pH monitoring undertaken

Low

General site activities

Vehicle or generator refuelling

Hydrocarbons, fuels

Moderate

• Risk register • ESRP • Site induction and staff training

• Drip trays must be in place during refuelling • Spill kit to be available in close proximity to the activity.

Low

Unloading of Environmentally Hazardous Substances (EHS)

Hydrocarbons, pH

Moderate

• Risk register • ESRP • Site induction and staff training

• Transfer of EHS to the designated storage area promptly upon receipt.

• Spill kit available in close proximity to unloading area.

Low

Construction equipment storage (shotcrete pumps, compressors, generators etc.)

Oil, fuel and hydraulic fluid leakage

Moderate to Low

• Risk Register • ESRP • Site induction and staff training

• Regular inspection and servicing of equipment.

• Repair to minimise leakage.

Low

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Activity

Contaminants

Initial risk

Procedural controls

Physical controls

Residual risk (with controls in place)

Equipment washdown

Sediment, hydrocarbons, oil & grease, heavy metals

Moderate

• Risk register • Site induction and staff training

• Washing of equipment shall only be undertaken within the excavation area, or areas where runoff is collected and pumped to the WTP. • A wheelwash is provided at the vehicle exit from CSA 5 as a final mitigation.

• All collected washwater will be diverted to the onsite WTP and then discharged to stormwater or sewer.

Low

Waste handling and storage

Sediment, hydrocarbons, oil & grease, heavy metals

Moderate

• Risk register • ESRP • Site induction and staff training

• All waste bins shall be stored in a covered area on-site or have lids.

Low

Equipment laydown

Oil & grease, heavy metals

Low

• Risk register • Site induction and staff training

• Regular inspection and servicing of equipment.

• Repair to minimise leakage.

Low

Vehicle parking

Oil & grease, heavy metals

Low

• Risk register • Site induction and staff training

• Spill kit available.

• Regular inspection and servicing of vehicles.

Low

Low

• Risk register

Offices

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-

-

Low

Industrial and Trade Activity Environmental Management Plan

4.

Site Drainage

The overall approach to site drainage and treatment is dependant on the specific activities. Overall the approach is summarised in Table 4.1 below.

Table 4.1

Summary of treatment approach

Initial risk

Activity type

Minimum treatment requirements

Relevant Management Plans

High

ITA Activities

Diverted to water treatment plant

• This ITAEMP for management methods; • ESCP and FTMP for treatment plant.

Moderate

ITA and general activities

Diverted to water treatment plant to via site specific erosion and sediment control devices where contaminant is limited to sediment.

• This ITAEMP for management methods for ITA activities; • ESCP and FTMP for treatment plant and non ITA activities.

Low

General activities

Direct to stormwater, or via site specific erosion and sediment control plan.

• ESCP and FTMP for treatment plant and non ITA activities.

All existing stormwater drains within construction and construction support areas are to be diverted around the works. The relocated catchpits are shown in Appendix B of the ESCP (Appendix H of the CEMP). Any remaining stormwater catchpits within or immediately downstream of the work zones will be completely blocked with drain plugs. Any contaminated runoff that accumulates in the catchpits will be removed via a vacuum truck. If this is not practicable, careful placement of sandbags or bunds around the catchpits will be undertaken.

The release of contaminants to the stormwater network is managed using the controls described in the ESCP and this ITA EMP. Discharge to sewer network may also be undertaken where water quality requirements for stormwater cannot be met, subject to permission from Watercare. Drainage plans have been prepared for CSA 4 and CSA 5 (refer to Appendix H of the CEMP) to show the location of the water treatment plants (WTPs), ESCP devices, any catchpits, diversion bunds and the stormwater discharge monitoring points.

In general the areas of the site with high risk activities, where management of both sediment and elevated pH is important, are bunded with discharges treated by one of the WTPs. Areas with moderate risk activities are either bunded (e.g. storage of environmentally hazardous substances), drain into or are pumped to a WTP where elevated pH is expected, or treated by traditional sediment retention devices, specifically Sediment Retention Ponds (SRPs) and Decanting Earth Bunds (DEBs). The remaining areas of the site (including the low risk ITA activities) are managed in accordance with the ESCP which include discharge direct to stormwater where no sediment or contaminants are expected.

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Industrial and Trade Activity Environmental Management Plan Final as-built drainage plans for the main works area will be prepared following the completion of the works. These plans will show the locations of all stormwater catch pits and discharge locations within the main works area.

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5.

Management Procedures and Mitigation Measures 5.1 Bentonite Plant

The main environmental risks associated with the bentonite plant are the discharge of chemicals from the operation of the plant and/or the discharge of sediment laden water to stormwater drains within the main works area, which in turn discharge into the Waitematā Harbour.

To avoid or minimise any discharges from the bentonite plant to the surrounding environment, each plant is designed and operated as follows: •

The entire bentonite plant is bunded to contain any spilt material or bentonite slurry in the event of a pipe or pump failure during transfer of the slurry. Any surface water collected in the bund is pumped out to the on-site WTP.

•

Sodium bicarbonate and bentocyrl are added to the bentonite slurry. Neither chemicals are classified under HSNO as hazardous and are stored within the bunded bentonite plant area.

No other environmentally hazardous substances are required as part of the bentonite plant operation.

•

In the event of a spill outside of the bunded area, the standard spill control procedures will be implemented to contain and manage the spill (refer to Section 6 of this ITA EMP).

•

In addition, a Bentonite Plant Spill Response Plan has been prepared and will be implemented (refer Appendix C). This Plan outlines the environmental controls and spill response procedures specific to the operation of the plant detailed in Section 2.3 of this ITA EMP. The extent of the bunded areas of the bentonite plant that will be sealed off during the works are shown in the Stormwater Drainage Plan in the Bentonite Plant Spill Response Plan.

5.2 D-Wall Construction The main environmental risk associated with D-wall construction is the discharge of sediment laden water and high pH to the stormwater networks.

To avoid or minimise any discharges from the construction of D-walls at CSA 5, the works are managed as follows: •

The entire D-wall construction area drains to a low point from which any runoff is pumped to the on-site WTP.

•

All stormwater catchpits within the works areas have been removed or diverted to the WTP.

•

In the event of a spill outside of the bunded area, the standard spill control procedures will be implemented to contain and manage the spill (refer to Section 6 and Appendix B of this ITA EMP).

5.3 Soil Mixing Plant The main environmental risk associated with operation of the soil mixing plant is the discharge of sediment laden water and elevated pH from cement used in the grout slurry mix.

To avoid or minimise any discharges from the jet grout plant into the surrounding environment, the plant will be designed and operated as follows: •

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The soil mixing plant is bunded, with any surface water collected in the bund being pumped out to the on-site water treatment plant. | Mt Eden Main Works

Industrial and Trade Activity Environmental Management Plan •

In the event of a spill outside of the bunded area, the standard spill control procedures will be implemented to contain and manage the spill (refer to Section 6 of this ITA EMP).

The extent of the bunded areas of the soil mixing plant is shown in the CSA 5 site layout in Figure 21.

5.4 Ground Improvement The main environmental risk associated with ground improvement works is the discharge of sediment laden water and high pH to the stormwater networks.

To avoid or minimise any discharges from the ground improvements, the works are managed as follows: •

Regular inspection of hoses and connections from the soil mixing plant area for leaks.

•

All stormwater catchpits have been removed or diverted.

•

The ground improvement works form an excavation and any contaminated water that collects in the area will be pumped back to the WTP.

•

In the event of a spill outside of the bunded area, the standard spill control procedures will be implemented to contain and manage the spill (refer to Section 6 of this ITA EMP).

5.5 TBM Component A Plant The main environmental risk associated with the TBM “Component A” plant in the Technical Area of CSA 4 is the discharge of sediment laden water with elevated pH from the cement, pulverised fly ash and bentonite used in the Component A slurry mix.

To avoid or minimise any discharges from the Component A plant to the surrounding environment, the plant is designed and operated as follows: •

The entire Component A plant including all raw material silos is bunded to contain any spilt material or slurry mix in the event of a pipe or pump failure during preparation or transfer to the TBM. Any surface water collected in the bund is pumped out to the on-site WTP.

•

All raw material silos are fitted with high level sensors, interlocks and alarms to prevent overfilling, and all bulk material raw material refills and plant operations are supervised by staff trained in standard operating procedures and emergency response.

•

Regular inspection of hoses and connections from the Component A plant area for leaks.

•

In the event of a spill outside of the bunded area, the standard spill control procedures will be implemented to contain and manage the spill (refer to Section 6 and Appendix B of this ITA EMP).

5.6 Tunnel Segment Storage The main environmental risk associated with the tunnel segment storage at CSA 4 is the discharge of elevated pH from stormwater in contact with the concrete segments.

To avoid or minimise any discharges from the segment storage to the surrounding environment, the plant is designed and operated as follows: •

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The segment storage area drains toward the excavation of the tunnel entrance. Any accumulated stormwater is contained and pumped back to the WTP at CSA 4. | Mt Eden Main Works

Industrial and Trade Activity Environmental Management Plan •

All stormwater catchpits have been removed and diverted to beyond the CSA 4 area.

5.7 Muck Bin Area The main environmental risk associated with the storage of material at the muck bin at CSA 5 is the discharge of sediment laden water and high pH to the stormwater networks.

To avoid or minimise any discharges from the muck bin area the works are managed as follows: •

The muck bin area is graded to a low point sump which is pumped to the on-site water treatment plant.

•

In the event of a spill outside of the bunded areas in the CSA, the standard spill control procedures will be implemented to contain and manage the spill (refer to Section 6 and Appendix B of this ITA EMP).

5.8 Diesel Tank and Generator A key environmental risk associated with the diesel tank at CSA 4 and diesel fuelled generator at CSA 5 is the discharge of hydrocarbons to the stormwater networks.

To avoid or minimise any discharges from the diesel tank or generator, the works are managed as follows: •

Both the diesel tank and generator are located within bunded areas, and any runoff that collects in the bund is pumped to the on-site water treatment plant.

•

All refuelling of the tank or generator will be supervised by workers trained in emergency response.

•

Drip trays are in place during refuelling activities for reduction of incidental contamination of runoff in the bund.

•

All stormwater catchpits have been removed and diverted to beyond the CSA 4 and CSA 5 areas.

•

In the event of a spill outside of the bunded areas in each CSA, the standard spill control procedures will be implemented to contain and manage the spill (refer to Section 6 and Appendix B of this ITA EMP).

5.9 Stormwater and Groundwater Treatment Groundwater and stormwater which collects in the excavation areas and bunded areas during construction works will be treated as detailed in the ESCP and the FTMP (refer to Appendix H of the CEMP). Flocculants (both chemical or non-chemical) will be used to settle out sediment. Dosing for pH treatment will also be undertaken in the WTP as required to ensure water discharged from the system will not result in adverse effects on the receiving environment. The WTP at CSA 4 is located to the northeast of the Technical Area and the WTP at CSA 5 is located adjacent to the entrance off Water Street.

The WTP operation is outlined in detail in Section 3 of the FTMP for the main works (Appendix C of the ESCP).

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Industrial and Trade Activity Environmental Management Plan Discharge to sewer network may also be undertaken where water quality requirements for stormwater cannot be met. Any discharges to the sewer network will be in accordance with the terms of a Trade Waste Agreement to be established with WaterCare.

5.10 Environmentally Hazardous Substance Management The principal environmentally hazardous substances that are stored and used at CSA 4 and CSA 5 during the construction works will include: •

Fuel (e.g. petrol, diesel);

•

Oils and greases;

•

Dry grout, cement, pulverised flyash and bentonite;

•

Sodium silicate accelerator (Component B);

•

Concrete and asphalt (use only, will not be stored on site); and

•

Water treatment chemicals (for sediment settling and pH adjustment e.g. flocculation agents and sulfuric acid).

All chemicals are stored in a secure area with secondary containment sized to contain at least 110% of the largest container in the event of a spill. The main storage area at each site is the hazardous goods storage area indicated on each CSA layout provided in Figures 2-1 to 2-4. The main chemical store at CSA 4 is on the western side of the Technical Area and at CSA 5 is to the northeast of the site adjacent to the muck bin. There is also some local storage of chemicals at each WTP. For all local storage, chemicals must be stored on spill pallets to provide appropriate secondary containment.

Safety Data Sheets (SDS) for all of the chemicals used or stored in the main works area are kept in the main works site office with a sub-set on file at each storage location relevant to the specific materials being stored. A Hazardous Substances and SDS register shall be kept on-site at each CSA and regularly maintained to ensure it is up to date with the chemicals and volumes of chemicals used and stored on-site. An indicative inventory of hazardous substances has been provided as Section 5.15 of the CEMP. Spill kits and associated spill response equipment are to be located as follows: • •

For CSA 4: at the spoil store, the water treatment chemical storage area, the Technical Area vehicle entrance, the A Component plant and the workshops; For CSA 5: at the soil mixing and bentonite plant bunded area, the water treatment chemical storage area and the workshop.

5.11 Waste Management For the purpose of the main works, waste material refers to items removed from worksites and road carriageways, such as surplus or reject spoil, excavated seal, pipes, rubbish detritus and any other unwanted materials. Appropriate disposal shall be arranged for any material that requires off-site disposal.

If hazardous material requires off-site disposal, it will be disposed of safely, through an appropriate contractor authorised to handle, transport, process or safely dispose of the waste concerned to an approved disposal facility.

Any waste bins on-site will either be stored undercover or will be installed with covers to prevent rainwater ingress.

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Industrial and Trade Activity Environmental Management Plan

5.12 Wash-down A wheel wash is provided at the site exit of both CSA4 and CSA5 to minimise tracking of sediments off site. The wheel wash water is contained and drains to the associated WTP or collected and removed off-site via sucker truck.

No road vehicle wash-down will be undertaken on-site at either CSA outside of the designated wheel wash. The location and nature of the construction works, along with the construction methodology serves to minimise the potential for site vehicles to drive over areas of open excavation or unpaved areas and track dirt onto the surrounding road network.

In the event of material being spilled onto the ground around the tunnelling excavation or from trucks transporting the spoil from the spoil store at CSA 4, the material will be cleaned prior to the vehicle leaving the site. This may involve some localised washing of vehicles and tyres. Any runoff from the wash down area will be directed to sediment control devices with associated sediment settling and monitoring prior to discharge.

Some washing of machinery within the excavation areas may be required. In this instance, washing of machinery is undertaken using a hose or water blaster on-site within areas of excavation only. All runoff within these areas is either drained to ground or captured and pumped to the WTP.

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6.

Spill Response

The management of spills will differ depending on the quantity, type of material and location of the spill. A general ESRP has been prepared for the main works (refer to Appendix B of this ITA EMP).

The ESRP includes provision that in the event of all spills over 20 litres, or any spill of Environmentally Hazardous Substances, which has entered the stormwater system, a water-body or has contacted unsealed ground, the spill shall be reported immediately to the AC 24 Hour Pollution Hotline (09-377-3107).

As described in Section 5.1, spill kits for CSA 4 are to be located at the tunnel spoil building (central CS4 area), the water treatment chemical storage area, A Component plant and the workshops. The spill kits for CSA 5 are to be located at the soil mixing and bentonite plant bunded area, the water treatment chemical storage area and the workshop. Signage relating to spill response procedures will be located at each vehicle entrance to each CSA during each stage of work.

Each spill kit has a register of contents and an inspection sheet. Each spill kit is inspected monthly to ensure all contents are present and there is no rubbish in the kits. The inspection sheet shall be signed during each inspection.

Specific spill response procedures for the bentonite plant at CSA 5 are detailed in the Bentonite Plant Spill Response Plan (refer to Appendix C of this ITA EMP).

In addition, a specific spill response plan for jet grout activities will be prepared. As the location of the use of jet grout may vary during the project (rather than being fixed in a single location like the bentonite plant), this will need to be prepared for each proposed location to ensure the controls are relevant.

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7.

Discharge Monitoring and Reporting 7.1 Monitoring

Discharges from the site will be monitored as required by resource consent condition 173 listed in Table 1-1. The water quality discharge monitoring programme is set out in Section 8 of the FTMP (Appendix H of the CEMP) for discharges from the site which outlines the sampling locations, monitoring parameters, monitoring methods, trigger levels and monitoring reports.

7.2 Reporting Reporting of the monitoring results shall be undertaken in accordance with resource consent conditions 176 and 177, as outlined in Table 1-1. Section 9.5 of the FTMP (Appendix H of the CEMP) details the different water quality reports that will be supplied to Auckland Council (Team Leader Central Monitoring) throughout the main works. These include an initial monitoring report within eight weeks following the start of the monitoring, any non-conforming result report, and the annual monitoring report.

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8.

Environmental Compliance Management and Review 8.1 Site Inspections

Regular inspections of the main works areas will be undertaken throughout the construction duration as outlined in Section 6.2 of the CEMP. Site inspections will include inspections of industrial and trade related activities to ensure the integrity of activities and devices is maintained and to minimise the potential for the discharge of contaminants from the main works areas that might have adverse effects on the receiving environment. Site inspections will be conducted (and documented) weekly and include the following elements: •

Check bunding and containment systems around hazardous substances are intact;

•

Check water treatment systems are operating correctly to manage contaminated water;

•

Check all loading and unloading areas are clear of spillage and debris;

•

Check the appropriate storage of materials on-site in order to prevent spillage and have appropriate HAZCHEM warning and information signage;

•

Check site for evidence of spills that require clean up;

•

Check construction vehicles for signs of leakage;

•

Check spill kits are fully stocked, clearly labelled and appropriately located; and

•

Check waste skips and containers for capacity, signs of leakage and ensure they are covered to prevent rain water ingress.

8.2 Environmental Audits An internal environmental and sustainability audit will be undertaken 30 days from commencement of each key stage of the main works and at least a quarterly basis. The purpose of the audit is to check the implementation of, and compliance with, environmental management procedures and controls, including those outlined in this ITA EMP. The audit findings will be reported accordingly to enable any discrepancies to be identified and actioned.

External environmental and sustainability audits will be completed as per the main works Audit Schedule, and at least annually, to assess the effectiveness of the Environmental Management System.

Refer to Section 6.3 of the CEMP for further detail on these audits.

8.3 Non-Conformance, Corrective and Preventative Action Corrective action is required on the basis of the occurrence of substandard performance being observed or experienced, resulting in an environmental complaint, incident or emergency or where a significant environmental incident or emergency could have occurred. Refer to Section 6.4of the CEMP for further detail on corrective and preventative action during the main works.

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9.

Training 9.1 Employees and Subcontractors

All main works staff (including subcontractors) will undergo general environmental awareness training, along with training in relation to the risks associated with industrial and trade activities outlined in this ITA EMP and to ensure that the appropriate control measures are properly implemented.

Suitable induction and ongoing environmental training will be established and maintained to ensure employees and subcontractors are aware of: •

The importance of conformance with the Environmental Policy, the requirements of the CEMP and company procedure;

•

The significant environmental aspects, actual or potential, of activities and the environmental benefits of improved performance;

•

Their roles and responsibilities in achieving conformance with the environmental policy, company procedures and this ITA EMP;

•

The potential consequences of departure from specified operating procedures;

•

Spill response and emergency procedures; and

• Accident and incident reporting and methods of prevention.

Refer to Section 4.2 of the CEMP for further detail on employee training.

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Appendix A: ISCA Requirements Table A identifies the ISCA Credit Requirements relevant to this ITA EMP and where they are addressed in the documents.

Table A: ISCA Requirements Credit

Requirement *

Relevant section

Comments

DIS-1 Level 1

Baseline studies of existing receiving water environment have been carried out for the Project

Refer to the Water Quality Assessment Report by Golder Associates

Refer also to the Flocculant Treatment Management Plan

DIS-1 Level 1

Predictions for receiving water quality impacts have been developed for construction

Section 3

Refer also to the Water Quality Assessment Report by Golder Associates, dated Dec 2014 and the Flocculant Treatment Management Plan

DIS-1 Level 1

Measures to minimise adverse impacts to local receiving water quality identified and implemented

Sections 3,4, 5 and 7

Refer also to the Flocculant Treatment Management Plan and Contaminated Soils Management Plan

DIS-1 Level 1

Monitoring of water discharges and receiving waters is undertaken at appropriate intervals and at times of discharge during construction

Section 7

Refer also to the Flocculant Treatment Management Plan

DIS-1 Level 2

Modelling demonstrates no exceedances of water quality goals

Section 7

Refer also to Monitoring Results and Reports

DIS-1 Level 2

All stormwater leaving the site is treated or filtered in accordance with appropriate urban stormwater guidelines unless it occurs during a 6 hour 1 in 5 year storm event

Section 4

Refer to the Erosion and Sediment Control Plan and the Flocculant Treatment Management Plan

* Refer to ISCA Rating Tool for full details of the requirement

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Appendix B: General Emergency Spill Response Plan Purpose and Objective of Plan Environmentally Hazardous Substances (EHS) will be present in Project construction areas. This Emergency Spill Response Plan (ESRP) relates to the management of spills of EHS’s and the prevention of adverse environmental effects at CSA 4, CSA 5 and the active construction zones.

The objective of this ESRP is to ensure that emergency spills are handled in an appropriate manner to ensure safety of all personnel and to prevent damage to the environment.

2.0

Spill Response

Spillages will be managed and cleaned up on site in accordance with this ESRP. Any contamination of stormwater or groundwater within the excavated area will be treated as per the main works ESCP prior to release or disposal.

Spillages will be managed and controlled within the site. Spill risk will be managed through structural and procedural controls. In the event that these controls fail, management will be by way of adherence to the procedures outlined in this ESRP.

3.0

Hazardous Substances and Spill Response Procedures

Safety Data Sheets for all hazardous substances associated with the Project construction works are held at the site office at each CSA. These will be consulted to determine the appropriate course of action to take in an emergency situation, e.g. spillage.

Spill kits and associated equipment are located at each vehicle entrance to the site as shown on the attached stage plans.

4.0

Key Contacts

Key Project contacts in the event of a spill or release of EHS are listed in Section 4.1.2 of the CEMP.

5.0

Key emergency services

Key emergency services to be contacted in the event of a spill or release of EHS are listed below: Emergency Service

Role/Responsibility

Phone Number

Auckland Council Pollution Hotline

Spills to stormwater systems

(09) 377 310

Watercare Services

Spills to stormwater/sewage systems

(09) 442 2222

Police

Traffic Control Evacuation Crowd Control Investigation of Fatalities

111

Ambulance

Treat Injured Transport Injured

111

Fire and emergency New Zealand

Fight Fires Contain Spillage Rescue

111

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Emergency Spill and Runoff Response Are you able to safely deal with the spill?

NO

YES

1.

BE SAFE:

Determine type of protective equipment required from SDS and use it – isolate area – evacuate non-essential personnel – isolate ignition sources

2. STOP the SOURCE: Plug leak – right or reposition containers – turn off taps, valves or pumps

3. CONTAIN SPILT PRODUCT: Cover Sumps (drain covers, sandbags or booms) Close Interceptors Block stormwater drains (sandbags, temporary bunds or drain covers) Cover solid spills with plastic

4. NOTIFY Immediately: Your Supervisor and Auckland Council (09 377 3107) if greater than 20L or likely to enter stormwater drains ASSESS EXTENT OF SPILL, if required notify Fire 111 Police 111 Advise neighbours (where applicable).

Cooper and Company to be notified of spills with in / affecting Britomart Precinct

5. CLEAN UP: Only if trained and proper equipment is available Do NOT wash away with water into drains, use materials in spill kit,

6. DISPOSE Properly: Safely collect and dispose of contaminated absorbents and clean up gear by licensed contractor (e.g. ChemWaste)

7. REORDER and REVIEW: Replace all used spill kits materials and absorbents immediately document/record incident - investigate cause of spill - take action to prevent a repeat incident

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Evacuate area and call Fire Service 111

Industrial and Trade Activity Environmental Management Plan

Appendix C: Bentonite Plant Spill Response Plan Purpose and Objective of Plan The bentonite plant is located within CSA5. This Bentonite Plant Spill Response Plan (BPSRP) relates to the management of spills of liquid bentonite slurry and/or additives from within the bentonite plant.

The objective of this BPSRP is to ensure that emergency spills are handled in an appropriate manner to ensure safety of all personnel and to prevent damage to the environment.

Bentonite components and additives The fresh bentonite slurry is composed of water from the main fire hydrant and of bentonite and additives (sodium bicarbonate and bentocryl).

Mixing of bentonite with water and additives (sodium bicarbonate and bentocryl) to make a bentonite slurry, which will be temporarily stored within the silos before being used in the diaphragm wall construction.

Safety Data Sheets for the Bentonil, the Sodium Bicarbonate and the Bentocryl are held at the site office. These additives are not classified under HSNO as hazardous. Irrespective of this, all of these additives will be stored within the bunded bentonite plant area. No other hazardous substances will be required as part of the bentonite plant operation.

Structural Controls The entire bentonite plant is bunded to contain any spilt material or bentonite slurry in the event of a pipe or pump failure during transfer of slurry. A surface pump will be used to manually pump any surface water that collects within the bund to an onsite water tank or to the water treatment plant.

The bund will be checked on a daily basis for water accumulation, to determine whether pumping is required.

Once the water treatment plant has been commissioned, surface water from the bunded area will be pumped to the plant for treatment. This water will be treated prior to discharge to the stormwater system.

Washwater At the end of each shift the plant is washed down. Any washwater will be contained within the bunded area and pumped to the onsite water tank or the water treatment plant once commissioned.

Contingency Measures To prevent overflow from the silos: • • • • Page 46

• The float switches have been positioned to 2.5 m below the top of the silos, providing extra capacity in the top of the silos in the event of heavy rain • The level alarms have been tested during a trial run • The silos supply circuit has been checked and tested during a trial run • The levels of slurry inside the silos will be lowered down to a minimum level during any long weekend and/or holiday periods (e.g., during Christmas and New Year) | Mt Eden Main Works

Industrial and Trade Activity Environmental Management Plan To prevent the slurry line from bursting: • • • •

The slurry line network shall be tested and checked The slurry lines have been bought specifically for this project and are not second hand use The slurry lines materials and fittings have been procured considering a safety factor for slurry pressure.

The pumps have a maximum working pressure of 5 bars, and the hoses are designed for 10 bars working pressure with a safety factor of 3:1, with their connections being crimped

Spill Response Procedure – Within the bunded area The crew at the bentonite plant is composed of 1 plant operator and 2 plant assistants. The full plant will be checked by one member of the crew every 20 minutes to confirm no spillage/leakage has occurred.

In the event of a minor spill of bentonite slurry within the bunded area, the platform has been equipped with a slurry pump to suck the slurry back into the de-sanding plant. Two spare pumps have been provided for.

In the event of a major spill from the overflow or rupture of one or more silos the bund walls have been designed to contain the equivalent of 2 silos.

The spill will be sucked up with the slurry pump and pumped to an appropriate location (e.g., back into one of the silos).

Spill Response Procedure – Spills outside of the bunded area In the event of a bund breach or other spill (pipe burst) outside the bunded area the following process will be followed: •

Additional sand bags are available onsite. Depending on location of the spill, sand bags will be placed in key locations to contain the spill within the site boundary.

In the event of a spill beyond the site boundary the following process will be followed: • • • • •

Confine the spill with sandbags, booms or other suitable material Block off the closest stormwater catchpits Contact a waste disposal contractor to clean up the spill Notify the STMS who would decide whether the road needed to be closed, or if not they would direct traffic around the spill Notify the Environmental Manager (Sarah Sutherland 021 956 397). The Environmental Manager will notify the Auckland Council 24 hour pollution hotline.

Spill Response Procedure – Oil The oil at the plant is present in the enclosed gear box of the pumps. An oil spillage could potentially occur during the re-filling of the pump oil container. In addition a hydraulic oil spill could potentially occur if one of the hydraulic oil hoses to the Hydrofraise machine burst.

In the event of any oil spillage site staff will use the spill kit and follow the general emergency spill response procedure (ESRP) to contain and manage the spill (refer to Appendix B).

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Industrial and Trade Activity Environmental Management Plan One general purpose, and one oil only spill kit will be located adjacent to the plant. Each kit will have a register of contents, and an inspection sheet. Each bin will be inspected monthly to ensure all contents are present. Stocks of sand bags will also be checked during the monthly inspection.

Spill Response Procedure – Drills On a two-monthly basis the site will schedule and run a spill deployment exercise on the site related to the Bentonite Plant and/or Hydrofraise machine. These drills will enable staff to become knowledgeable and proficient in the response procedures outlined in this plan and spill response equipment available on the site. Any lessons learnt from these drills will be used to improve this spill response plan.

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Industrial and Trade Activity Environmental Management Plan

Appendix D: Jet Grout Plant Emergency Response Plan To be developed for each location

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Industrial and Trade Activity Environmental Management Plan

Appendix E: Record of CLG and Auckland Council Comments E1. CLG Comments An Mt Eden Community and Business Liaison Group (CLG) meeting was held on 11 May to discuss the Mt Eden Main Works and for the CLG to provide comments / feedback on the CEMP and subplans, including this ITA EMP. No comments were received from the CLG on this ITA EMP.

E2. Auckland Council Comments The ITA EMP was reviewed by Leon Blackburn, Senior ITA/ Stormwater Specialist. Leon provided the following comments on the ITA EMP: Section of this ITA EMP

Comment

Response

General

Appears written as planning document in terms of tone. The EMP is THE document of structural and procedural controls. i.e ‘documents the procedures to be implemented’ should read as ‘…are implemented’. Understood that EMP live document as per conditions of consent and implement version will address this as per condition 159.

The tone and approach is consistent with the overall management plans.

Cross references to various other plans. Refer 'documents reviewed’ section of this memo regarding cross references and applicability of specific conditions of consent.

Example section 1.3 of ITAEMP refers conditions 159 – 179. These also overlap with ‘other’ and details of WTP are in the FTMP, an appendix of ESCP.

The ITA EMP has included clarification around the relationships between the other plans.

1.3

Understand avoidance of duplication, FTMP has the water quality management required under ITA/Other discharge conditions, not LUC conditions because this is for more than just ‘sediment controls’. Comment more for future reference and clarity as to location.

No amendments required.

1.4 conditions

161(f) requires drainage plans.

Q: Is it correct that in terms of the ITAMP these will be for the ‘technical area’ of CSA 4 and CSA5, with the wider CSA4 plans being in the referenced ESCP?

Drainage plans are included in the ESCP and have not be included to avoid duplication.

166: MT Eden is CSA 4 and 5 {note for leon) comment in relation to section 2.2 of ESCP

Clarification made in plan that this ITA EMP on relates to CSA 4 and 5.

Amended to clarify approvals on if modification made.

169: seek clarity – is this saying that there are already minor modifications? Was this the move to the sediment pond for the majority CSA4 and ACZs? Noting CSA5 is tanks according to figure XX in section X.X of this EMP. Page 50

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Industrial and Trade Activity Environmental Management Plan

170: asbuilts. Section 5.1 of CEMP (to be checked) Oter as-built conditions 36(f), 65, 66. For ITA, must include cross sections and confirmation of capacities of the treatment system required under 168, specifically that for CSA 4 (Technical area) as per 171. Note that section 2.3 refers to volumes of 25m3, 450m3

As-builts will be provided as part of the ESCP.

Understand some detail is in ESCP, SSESCP in terms of runoff volumes etc 173: see comment in relation section 8 of FTMP. 174: little confused as to relevance of this requirement being in the FTMP given not requirement of wider ESCP. Detail review in comments on section of FTMP.

Monitoring at the outlet is part of overall FTMP as it relates to discharges from the WTPs.

1.6

Note that part of the annual reporting (and reporting of monitoring should be talking about the results in terms of actual discharge and comparison to ANZEEC and baseline from sampling required (and ongoing) under conditions 152-155.

Analysis of reporting included.

2.1 (page 15)

Talks about CSA4 and the activities undertaken here and in the ‘technical area’.

Q: Is the ‘technical area’ first row of the table in condition 168.

[LJB: Think I consider these two areas to have detailed drainage plans within ITAEMP].

ITA EMP amended to clarify that the technical area is part of CSA4.

3 (Table 3.1)

Q: Table is labelled as ‘general activities’. Are these specific to the technical area or both CSA 4 and 5?

Comment added outlining the inclusion of “general activities” within the table.

Q: Is the WTP referred to only in technical area CSA 4? Is there additional one in CSA 5 and for the remainder of CSA4? (i.e 3 WTPs?) Section 4’site drainage’ refers to appendix H of CEMP for drainage plans. Think for clarity it should be confirmed which WTP is receiving what.

The WTPs are specified in the ESCP. At present there is one WTP for CSA4 and one for CSA5.

Appears WTP in technical area of CSA4 will receive discharge from all of CSA4.

[LJB: Need to located larger/clearer plans to those in the figures in section 2].

4

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Without reviewing drawings yet, simple catchment plan for discharges/catchments of each WTP, sediment pond catchment and areas discharging directly to stormwater (with what quality checks on water quality?)

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Catchment and drainage plans included in the ESCP. These have not been included to avoid duplication.

Industrial and Trade Activity Environmental Management Plan Paragraph ‘ultimately all water will discharge..’ seems to contradict the paragraph above it. So actual flow from the site is 1) WTP, to sediment pond, to SWNetwork or 2) sediment pond to SWNetwork.

Table added clarifying the approach with low risk areas potentially discharging to stormwater.

Previously states some areas direct to SWNetwork.

All water at least via sediment pond. See comment on section X below in relation to WQS at inlets, outlets and final discharge points.

Q: One discharge point for each CSA?

Discharge points outlined in the ESCP.

5.2

Confirm that this is about overland flows and preventing them entering CSA5, hence ‘divert beyond’? All runoff from CSA5 via WTP.

Amended to clarify all runoff is diverted to WTP.

5.5, 5.6

Think clarifies earlier query re: WTP. Technical area has one WTP, CSA4 (segment storage) has an additional WTP?

Only one WTP is proposed for CSA 4 including the segment storage.

Requirement for drawing of each WTP (cross section, capacity calculations etc) [view section 3 of FTMP?] 5.10

Advocate use of simplified catchment and equipment location plans as part of operative EMP, indicating spill kit locations etc. Comment also relevant to SRP section.

Catchment plans outlined in ESCP and have not been included to avoid duplication.

7

See comments in relation to section 8 of FTMP.

Sampling will be undertaken at the outlets of the WTPs. This is detailed in the FTMP.

Appendix B

General query: Section 5 refers to spills to stormwater. Don’t all areas go via WTP and then the sediment pond? So for spill to enter SWnetwork needs to have escaped controls in the CSAs and made way to not shutoff sections of stormwater?

The controls for the different risks has been clarified in Section 4.

There may be spills outside of the ITA high risk areas which may go to SW, as well as the WTPs. The spill response plan also applies to all areas of the site, event those which drain to the WTPs.

Ap B Flow chart

Mentioned earlier simplified drainage plans, spilkit locations etc. copies for council, signage for site?

Something to consider.

The drainage plans are in the ESCP to avoid duplication.

Ap C Bentonite SRP

Q: Will this be structured into flow chart,/simplified procedural steps for training?

No changes to the plan are proposed at present. This plan has been adopted during works at the Downtown station works and at CSA3.

Record keeping for drills required. Section 4.2 of CEMP? Or specific to ITAEMP? Ap D Jet grout SRP

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Q: When will this be developed and provided?

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At present, the use and location of the jet grout plant are not certain. The plan will be developed prior to commissioning.

Industrial and Trade Activity Environmental Management Plan

Ap E

Q: Were comments received form CLG? Commentary unclear on whether received or not.

E3. Mana Whenua The ITA EMP was issued to Mana Whenua in May 2020 for review.

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No comments reviewed from CLG.

Industrial and Trade Activity Environmental Management Plan

Appendix F:

Register of Plan Updates

Annual review 20XX Updates Updates have been made to the following sections: •

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Date