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Erosion and Sediment Control Plan

Aotea Station Main Works Erosion and Sediment Control Plan

CRL-AOT-RME-LKA-PLN-800028 Revision: 000 Date: 5 March 2020

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Erosion and Sediment Control Plan

Aotea Station Main Works CRL-AOT-RME-LKA-PLN-800028

This document is uncontrolled when printed. This document should be printed in colour

Revision Status Revision

Date

Version details

Prepared By

Approved By

000

05/03/2020

Final for lodgement

Ellen Chang

Peter Roan

001

15/03/2020

Auckland Council Approval

Approval Status Name/Title

Signature

Date

Prepared by:

Ellen Chang Civil Engineer

05/03/2020

Reviewed by:

Caroline Secretin Principal Environmental Scientist

05/03/2020

Approved by:

Duane Rollo Associate Director â€“ Civil Infrastructure

05/03/2020

Approved by:

Peter Roan Consenting Lead

05/03/2020

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Glossary Abbreviation / Acronym ACZ CSA ESC ESCP ESRP FTMP HCl NA PAC WQDMP Term Flocculation Required water quality discharge standard

Sediment retention device Water treatment

Water treatment device Water treatment system Document ANZECC (2000) Guidelines GD01 GD05 TP108 Water Quality Assessment Golder Report

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Description Active Construction Zone Construction Support Area Erosion and Sediment Control Erosion and Sediment Control Plan Emergency Spill Response Plan Flocculant Treatment Management Plan Hydrochloric Acid Not applicable Polyaluminium Chloride Water Quality Discharge Monitoring Programme Description The use of chemical or non-chemical coagulants and flocculants to assist settlement. The required groundwater and surface run-off quality to be discharged to stormwater is defined as per resource consent condition 145c, i.e. provided testing demonstrates compliance with 50 times the Australian and New Zealand Environment Conservation Council (ANZECC) Guidelines for Fresh and Marine Water Quality (2000) for the protection of 95 percent of marine water species, and is free from petroleum hydrocarbons. Section 8.4 of the FTMP (refer Appendix C of the ESCP) provides detail about discharge quality. A device where sediment-laden runoff is captured for settlement to occur, this can be a containerised settlement tank or any settlement device. Water treatment (also referred to as chemical treatment) includes flocculation, coagulation, and pH adjustment involving the usage of chemical or non-chemical products. A device to assist settlement via flocculation and/or pH adjustment using chemical or non-chemical reactants. It is typically used in addition to a sediment retention device. A standalone sediment retention device, or a combination of a sediment retention device and a water treatment device to treat discharge to the required water quality discharge standard. An example is the water treatment area (within the CSA). Description Australian and New Zealand Environment Conservation Council Guidelines for Fresh and Marine Water Quality (ANZECC 2000), 2018. Stormwater Management Devices in the Auckland Region â€“ Guideline document 2017/001 (GD01), Auckland Council, December 2017. Erosion and Sediment Control Guide for Land Disturbing Activities in the Auckland Region â€“ Guideline document 2016/005 (GD05), Auckland Council, June 2016. Guidelines for stormwater runoff modelling in the Auckland Region TP 108, Auckland Council, April 1999 Auckland City Rail Link A2N Water Quality Assessment, Golder Associates (NZ) Limited, May 2016.

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Table of contents 1. Introduction ................................................................................................ 6 1.1

Aotea Station Overview..................................................................................................... 6

1.2

ESCP Staging ...................................................................................................................... 8

1.3

Purpose of the ESCP .......................................................................................................... 8

1.4

Relevant Conditions .......................................................................................................... 9

1.5

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

1.6

ESCP Review and updates................................................................................................ 12

2. Aotea Station Main Works ........................................................................ 13 2.1

Overview of Works .......................................................................................................... 13

2.1.1.

Active Construction Zone .......................................................................................... 13

2.1.2.

Construction Support Area Layout ............................................................................ 14

2.2

Earthworks ...................................................................................................................... 14

2.3

Topography and Drainage ............................................................................................... 15

2.4

Geology ........................................................................................................................... 16

2.5

Programme ...................................................................................................................... 17

2.6

Construction Methodology .............................................................................................. 17

3. Erosion and Sediment Control and Management ..................................... 18 3.1

Key Principles .................................................................................................................. 18

3.2

Erosion and Sediment Control Measures......................................................................... 18

3.2.1.

General ESC Measures .............................................................................................. 18

3.2.2.

Erosion and Sediment Source Control ....................................................................... 20

3.2.3.

Asphalt Works and Concrete Pumping / Pouring....................................................... 21

3.3

Specific Erosion and Sediment Control Measures ............................................................ 21

3.3.1.

Aotea Station Foundations ....................................................................................... 21

3.3.2.

Aotea Station Construction ....................................................................................... 22

3.3.3.

Aotea Station MEFH installation and structural fitout ............................................... 23

3.3.4.

CSA........................................................................................................................... 23

3.3.5.

Stockpiling ................................................................................................................ 23

3.3.6.

Settlement tank volumes .......................................................................................... 23

3.3.7.

Water Treatment...................................................................................................... 25

3.4

Contaminated Flows Management.................................................................................. 25

3.4.1. Page 4

High Risk Spillage Areas ............................................................................................ 25

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Erosion and Sediment Control Plan 3.4.2.

Other sources of contaminated flows ....................................................................... 26

3.5

Monitoring During Construction ...................................................................................... 26

3.6

Heavy Rainfall Response and Contingency Measures ...................................................... 27

3.7

Other Environmental Management Considerations ........................................................ 27

3.7.1. 3.8

Dust Control ............................................................................................................. 27

Site Reinstatement .......................................................................................................... 28

4. Roles and Responsibilities, Training and Complaints Response ............... 29 4.1

Roles and Responsibilities ............................................................................................... 29

4.2

Training ........................................................................................................................... 29

4.3

Complaints ...................................................................................................................... 29

Appendix A: ISCA Requirements ..................................................................... 30 Appendix B: ESCP Drawings ............................................................................ 31 Appendix C: Flocculant Treatment Management Plan ................................... 32 Appendix D: Record of CLG and Auckland Council Comments ....................... 33

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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 in the vicinity of Mt Eden Station. The CRL also involves the construction of two new underground stations at Aotea and Karangahape and the redevelopment of the station at Mt Eden (refer to Figure 1-1). The design and construction of the CRL infrastructure between the Aotea and Mt Eden Stations is being delivered by the Link Alliance.

Figure 1-1 CRL Route and Location

This Erosion and Sediment Control Plan (ESCP) has been prepared in relation to the Aotea Station main construction works (referred to as ‘Aotea Station main works’ throughout the Plan).

1.1 Aotea Station Overview Once completed, the Aotea Station will include platforms, lifts, escalators, rooms for housing stations and tunnel services equipment, an entrance building at Wellesley Street, two additional entrance buildings at Victoria Street, a Plenum at Kingston Street, services, internal and architectural finishings, structural fittings, utilities services diversions and connections. The location of the Aotea Station is primarily beneath Albert Street, connecting the Contract 2 (C2) cut and cover tunnels to the north and the tunnel-boring-machine (TBM) tunnels to the south. The works are approximately 380m long by 18m wide and will be excavated around 18-20m below ground level. Additional boxes branch off from the tunnel alignment at Kingston Street (to form the Plenum), Victoria Street (for two entrance buildings to the Aotea Station) and Wellesley Street (to form the main entrance building to the Aotea Station (herein referred to as the ‘Wellesley Street Entrance Structure’)). Error! Reference source not found. provides a indicative layout for the underground station box with the associated above-ground Wellesley Street Entrance Structure, entrance structures at Victoria Street and the Kingston Street Plenum. Page 6

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Figure 1-2 Indicative Aotea Station indicating length of underground station box with the associated above-ground Wellesley Street Entrance Structure, entrance structures at Victoria Street and the Kingston Street Plenum.

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Erosion and Sediment Control Plan

For context, Auckland Transport (AT) has obtained a resource consent for an Over Station Development (OSD) on the Bledisloe Car Park site (Council Reference R/LUC/2016/2647). The proposal involves the construction of a 24-level building comprising offices, retail and food and beverage tenancies, and public features including a plaza and a through site link. The proposed OSD is not part of the Link Alliance contract and will be progressed separately by Auckland Council/ Panuku. Given the nature and scale of the Aotea Station construction, works will be undertaken in a staged manner, involving: •

•

Five stages of early works (canopy removal, network utility relocation and site establishment work), being undertaken from October 2019 to March 2020 (Stages 1 to 3) and December 2019 through to August 2020 (Stages 4 and 5); these works have been authorised by separate Outline Plans (Council ref. OPW60345651 and OPW60348747); Main construction works (the ‘Aotea Station main works’) involving construction of the station box, associated above ground structures, mined tunnels for the rail tracks, internal finishings, structural fitout, all Mechanical, Electrical, Fire and Hydraulic (MEFH) installation, and architectural finishings1. The Aotea Station main works will be undertaken from early2020 through to late-2023; and Ground reinstatements (from late-2022) and urban realm improvements. These works will be described in a future Outline Plan2.

Refer to section 2 of the Construction Environmental Management Plan (CEMP) for a detailed description of the Aotea Station main works.

1.2 ESCP Staging To reflect the staged construction approach for Aotea Station, this ESCP will be developed in stages. This ESCP addresses the Aotea Station main works, which are detailed in the CEMP, and an overview is provided in section 2 of this ESCP.

1.3 Purpose of the ESCP This ESCP has been prepared to identify measures that will be implemented to mitigate and manage the potential adverse effects on the receiving environment from any erosion and sediment generation during the main works. This ESCP has been prepared in accordance with Conditions 53-58, 65-73 and 166 of the CRL Aotea to North Auckland Line (A2N) regional resource consent (land use consent R/LUC/2016/1890). This ESCP forms part of the CEMP for the Aotea Station main works.

It is noted the architectural finishing component of works (the exterior look and feel of the Aotea Station) will occur during Phase 5 of the Aotea Station main works (approx. 2022 – December 2023). These finishings are still being designed and determined. Once designs are completed a separate Outline Plan and suite of DWP’s will be prepared, describing the finishings and other urban realm reinstatements, including ground reinstatement. That Outline Plan package will address the relevant Urban Design related Designation conditions (Condition 47 – 54). Page 8 | Aotea Station Main Works

Erosion and Sediment Control Plan Chemical treatment is likely to be required to assist in the settlement of sediments during the construction works. A Flocculant Treatment Management Plan (FTMP) is included in Appendix C of this ESCP, and a brief description is included in section 3.3.7 of this ESCP. The ESCP shall be read in conjunction with other relevant Delivery Work Plans (DWP) and Management Plans (MP) required by the designation and resource consent conditions. The ESCP has been developed in consultation with the Aotea Community and Business Liaison Group (CLG) (as per resource consent condition 19). A record of the consultation outcomes is provided in Appendix D of this ESCP.

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

Condition No.

Condition

Relevant section of DWP

Erosion and Sediment Control Plan (ESCP) 53

At least 20 working days prior to the commencement of construction within a Construction Support Area (CSA) or Active Construction Zone (ACZ), the Consent Holder shall submit to the Council (Team Leader Central Monitoring) for certification an ESCP which provides for the management of all bulk earthworks to minimise any discharge of debris, soil, sediment or sediment-laden water beyond the site to either land and/ or stormwater drainage systems.

This ESCP

The Consent Holder shall request the Council's (Team Leader Central Monitoring) determination as to whether the ESCP can be certified, in writing, within 10 working days of receipt of the ESCP. No construction activity shall commence until certification from Council is provided.

Noted

An ESCP shall include, but is not be limited to, the following matters:

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• identification of construction zones and construction support areas;

2.1

• specific erosion and sediment control works for each Active Construction Zone (location, dimensions, capacity supporting calculations and design drawings), which should be in line with Industry Best Practice that will meet or exceed the performance of measures detailed in GD05;

• catchment boundaries;

• the timing and duration of construction and operation of control works (in relation to the staging and sequencing of earthworks);

3 (and CEMP)

• details relating to the management of exposed areas;

3.2 and 3.3

• reference to the Flocculent Treatment Management Plan and confirmation of erosion and sediment control measures necessary to give effect to that plan;

3.2.1

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Erosion and Sediment Control Plan • reference to the Contaminated Soils Management Plan and confirmation of erosion and sediment control measures necessary to give effect to that plan; and

3.4

• monitoring and maintenance requirements, including information on complaint investigation and response procedures, training, and roles and responsibilities.

3.5, 3.6 and 4 (and CEMP)

Any change to an ESCP shall be submitted to the Council (Team Leader Central Monitoring) for certification.

1.6

The Consent Holder shall request the Council's (Team Leader Central Monitoring) written determination as to whether the proposed change can be certified, to be provided within 10 working days of submission of the change. No activity reliant upon a change to the ESCP can be undertaken until the change has been certified.

Noted

The Consent Holder shall comply with the ESCP for the duration of the earthworks associated with the Project.

Noted

As Built Certification 65

Prior to the commencement of bulk earthworks, a certificate signed by a Senior Qualified Person shall be submitted to the Council (Team Leader Central Monitoring) to certify that the erosion and sediment controls (including diversion bunds, silt fences and sumps) have been constructed in accordance with the certified ESCP(s) as required by Condition 53 of this consent.

Noted

The certification from the Senior Qualified Person for these measures shall be supplied to the Council (Team Leader Central Monitoring) immediately upon completion of construction of those measures. Information supplied, if applicable, shall include:

Noted

• The contributing catchment area; • The shape of structure (dimensions of structure); • The position of inlets/outlets; and • The stabilisation of the structure. General Performance Standards 67

The Consent Holder shall ensure that there shall be no deposition of earth, mud, dirt or other debris on any road or footpath resulting from bulk earthworks on the subject site. In the event that such deposition does occur, it shall immediately be removed. In no instance, shall roads or footpaths be washed down with water without appropriate erosion and sediment control measures in place to prevent contamination of the stormwater drainage system, watercourses or receiving waters.

3.2

The operational effectiveness and efficiency of all erosion and sediment control measures specifically required as a condition of resource consent, including the certified ESCP referred to in Condition 53, shall be maintained throughout the duration of earthworks, or until the Project site is permanently stabilised against erosion.

3.5 and 3.6

The site shall be progressively stabilised against erosion at all stages of earthworks activity and shall be sequenced to minimise the discharge of contaminants to groundwater or surface water.

3.1 and 3.2

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The Consent Holder shall ensure that the erosion and sediment control measures are constructed and maintained in accordance with GD05, except where a higher standard is detailed in an ESCP/FTMP, in which case the higher standard shall apply.

3.2.1, 3.3.7, 3.4 and 3.5

Sediment control measures shall be inspected on a weekly basis and after a significant storm event to ensure effective operation.

3.5

The Consent Holder shall ensure that all material removed from or delivered to the Project site shall be covered during transportation.

3.2.2

Contaminated Soils Management Plan 145

Any perched groundwater, or surface run-off water, encountered within the excavation area requiring removal shall be considered as potentially contaminated, and shall either: a. be disposed of by a licensed liquid waste contractor; or b. pumped to sewer, providing relevant permits are obtained; or c. discharged to the stormwater system, provided testing demonstrates compliance with 50 times the Australian and New Zealand Environment Conservation Council (ANZECC) Guidelines for Fresh and Marine Water Quality (2000) for the protection of 95 percent of marine water species, and is free from petroleum hydrocarbons.

3.4, Contamination Development Work Plan (CDWP), and Industrial and Trade Activities Environmental Management Plan (ITA EMP).

Discharge Monitoring 166

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

Exposed Area Not to Exceed (m2)

25,000

9,000

36,000

6,500

ITA EMP

*CSA 1 refers to the Aotea Station works. 167

In the event that any CSA requires an increase in area, the following information shall be provided to the Team Leader â€“ Central Monitoring whose certification shall be requested prior to implementation:

No increase in area is proposed.

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. 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: Works/ Controls Device Catchment Design Requirements Area 2 x Settlement Tanks located on CSA 4

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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

3.3 and ITA EMP

Erosion and Sediment Control Plan

169

Inlet protection measures

On all catch pits within CSA areas

2 x Settlement Tanks located in CSA 1, CSA 2, CSA 3, CSA 4 and CSA 5 Bunding of Environmentally Hazardous Substances

All Active Construction Zone (ACZ)

Design in accordance with Auckland Council Best Management Practice: Catch pit Protection Area (AC 2015). Settlement Tank sizing to be based on 2% of the contributing catchment

As required

110% largest container

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

Noted

b. Supporting information that confirms how the proposal does not affect the capacity or performance of stormwater management system.

1.5 Sustainability The Link Alliance is seeking an Infrastructure Sustainability Council of Australia (ISCA) Infrastructure Sustainability (IS) Rating. Further details can be found in the CEMP and Sustainability Rating Management Plan. Project sustainability requirements that relate directly to this ESCP are included in Appendix A. These requirements are imbedded within this ESCP 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. Further detail on sustainability is provided in section 1.7 of the CEMP.

1.6 ESCP Review and updates This ESCP is a live document that will be reviewed at least annually, or as a result of: • • •

A material change to the project, or to address unforeseen erosion and sediment runoff effects arising from construction, or unresolved complaints.

Any material changes to this ESCP must be certified by Auckland Council prior to any on-site activity reliant upon the change commencing (as per conditions 42 and 43 of resource consent). Refer to the CEMP for further detail on the review and updating process.

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Aotea Station Main Works 2.1 Overview of Works

The Aotea Station main works will involve three main phases of work. Each phase of work involves multiple construction activities which will be undertaken throughout the Aotea project site. The phases associated with the Aotea Station main works involve: • • •

Foundation works to form the perimeter walls of the station box and underground running tunnels. This involves diaphragm wall construction, roof construction, piling and jet grouting; Construction of the Aotea Station platforms, main station structure (at Wellesley Street), concourse, entrance structures (at Victoria Street) and Plenum (at Kingston Street), and; Structural fitout of the Aotea Station including MEFH installation, and internal and architectural finishings.

The works require the operation of a Construction Support Area (CSA) within the Bledisloe House car park site and a portion of Mayoral Drive. Equipment used to undertake these works will be predominantly situated in the CSA. Upon completion of the Aotea Station main works, the area will be repurposed in preparation for urban realm reinstatement works2. The methodology for the construction of the Aotea Station is predominantly based on a ‘top down’ and ‘bottom up’ approach. The ‘top down’ approach relates to the southern end of Albert Street (south of Durham Street) and involves the installation of the ‘roof structure’ early on, which enables a limited number of traffic lanes to operate concurrently with the construction of the station, which occurs beneath. This approach reduces the construction effects on traffic flow within the city centre. The tunnel alignment on the northern end of Albert Street (north of Durham Street) will be constructed using a ‘bottom up’ methodology. A detailed description of the Aotea Station main works is included in the CEMP and includes; • • •

an overview of the works including indicative timeframes in Table 2-1. the construction sequencing including equipment and earthworks volumes for the works in Table 2-2. further detail of the CSA in Section 2.6.2 of the CEMP. Drawings indicating the staging of the construction activities and proposed layout of the CSA is provided as Appendix B.

It is noted that, public realm reinstatement works and details of architectural finishings for the Aotea Station (Condition 47 – 54 of Designation 2500-1)2, will form part of separate Outline Plan packages to be prepared in the future prior to the commencement of the respective works.

2.1.1. Active Construction Zone The Aotea Station main works will be undertaken throughout a work zone referred to as an Active Construction Zone (ACZ), in accordance with the A2N consent. Further detail is provided in section 2.6.1 of the CEMP. Erosion and sediment generation is expected to occur throughout the ACZ during the Aotea Station main works. ESCP drawings attached in Appendix B of this ESCP show the location of the ACZ.

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2.1.2. Construction Support Area Layout The CSA located in Bledisloe carpark will be established during the early works and will be operational from the start of Aotea Station main works. Further detail is provided in the CEMP and a summary of the key plant and activities within the CSA for the purpose of this ESCP is provided below: • • • •

• • • •

Bentonite treatment and D-wall treatment (such as jet grouting) areas; 600m3 surge pile (footprint area of 150 m2) located on the south-western corner of the site compound; Bentonite, polymer and material storage; The specifically designated water treatment area will treat dirty runoff, water from within excavations and water from concrete wash-off, and runoff collected within the bunds of high risk spillage areas (i.e. bentonite plant and jet grouting areas); Main vehicle entrance to the station trench; Tunnel Boring Machine (TBM) retrieval locations; Entrance/exit to CSA for trucks (with stabilised entry and exit) through Mayoral Drive; and Entrance to the CSA for service vehicles will be through the eastern side of the CSA.

2.2 Earthworks Earthworks associated with the Aotea Station main works will largely comprise: • • • • • • •

Excavation to install the Station perimeter wall and D-Wall; Excavation to install the bored piles for the Northern Running Tunnels; Excavation of the Northern Running Tunnels; Excavation of the Station area in the Southern Section; Excavation to construct the entrance building; Excavation associated with the establishment of the temporary works platform south of Wyndham Street; and For the CSA: excavation required to complete CSA works onto Mayoral Drive.

The approximate earthwork areas and volumes required for the Aotea Station main works are outlined in Table 2-1. Refer to section 2.3 of the CEMP for a detailed breakdown of the earthwork areas and volumes.

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Erosion and Sediment Control Plan Table 2-1 Aotea Station main works approximate earthworks areas and volumes

Phase 3

Construction Works Area

Approx. Earthworks Area m2

D-wall construction

820

Approx. Earthworks Volume m3 18,040

Pilings

310

4,830

Jet grouting

800

7,630

141,070

1,250

23,090

1,000

11,050

188,830

Phase 4

Top-down construction within station roof in Southern section Bottom-up construction along Northern area of station Phase 5 Aotea Station internal fitout (MEFH installation and architectural fit out) Aotea Station CSA Total for Aotea Station main works

2.3 Topography and Drainage The overall site topography generally slopes down towards Queen Street with a steeply rolling terrain. The receiving environment for the site is the Queens Wharf approximately 1km north of the site, which ultimately discharges into the Waitemata Harbour. Albert Street, Victoria Street West, Kingston Street, Wellesley Street West and Mayoral Drive are all serviced by existing catchpits that connect to an existing stormwater system. The majority of these catchpits will be abandoned or relocated during the early works phase. The catchpits proposed to be abandoned and relocated are shown in the ESCP drawing attached in Appendix B of this ESCP. There is an existing overland flow path (OLFP) that flows alongside Albert Street and down towards Queen Street (see Figure 2-1). There are small areas of 100-year Annual Recurrence Interval (ARI) flood plain alongside Albert Street, but most flows are contained within the existing stormwater network. The slopes in this area range from 9% to 20% at the steepest sections. Myers Street slopes inwards towards the Bledisloe building and is serviced by existing catchpits within the carpark that connect to an existing stormwater system. There is an OLFP that flows down to Queen Street (see Figure 2-1). There are small areas of 100-year ARI flood plain on Mayoral Drive and on the eastern boundaries of the carpark, but most flows are contained within the existing stormwater network. The slopes in this area range from 11% to 15%. There are no flood sensitive areas located within the immediate work zones.

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Figure 2-1 Overland flow paths and flood sensitive areas in the Aotea Station site area

2.4 Geology The excavation work for trench construction will be located through man-made fill material underlain by Tauranga Group sediments and East Coast Bays Formation (ECBF) residual soil and volcanic deposits of the Auckland Volcanic Field of various weathering grades. The discontinuous series of perched groundwater zones overlay the more continuous regional groundwater table within the ECBF - which falls to the north (towards the harbour) and to the east (towards the station box). The regional groundwater table lies within the ECBF and is at approximately 5 to 10 m RL. The station box construction will interrupt the perched groundwater and existing regional flow regime over its full length.

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Erosion and Sediment Control Plan Refer to the Groundwater and Settlement Monitoring and Contingency Plan (GSMCP) attached in Appendix L of the CEMP for more details. The 2016 PDP Groundwater Technical Report2 has indicated a maximum total inflow to the station of a range of approximately 8 â€“ 16.7 m3/day. This volume has been used for the purpose of sizing the sediment retention devices (settlement tanks).

2.5 Programme The Aotea Station main works are anticipated to take approximately 45 months to complete, occurring from April 2020 to December 2023 (approximately) as detailed in Table 2-1 in Section 2.2 of the CEMP. Some construction activities outlined in each phase of the Aotea Station main works will occur in parallel.

2.6 Construction Methodology The Aotea Station main works will be divided into stages as described in the CEMP.

Auckland City Rail Link A2N: Groundwater Technical Report, Pattle Delamore Partners Ltd, May 2016. Page 17 | Aotea Station Main Works

Erosion and Sediment Control Plan

Erosion and Sediment Control and Management

Erosion and sediment control measures will be designed, installed and maintained in accordance with Auckland Council “Erosion and Sediment Control Guide for Land Disturbing Activities in the Auckland Region”, Guideline Document 005 (GD05). It is noted that GD05 has superseded Auckland Council Technical Publication 90 (TP90) “Erosion and sediment control guidelines for land disturbing activities in the Auckland Region”, which is referred to in the consent conditions.

3.1 Key Principles Key erosion and sediment control principles applicable to the main works are as follows: • • • • •

•

Selection of construction methodologies and staging of construction to limit the duration and area of earthworks exposed to erosion at any given time. Minimise total area of disturbance by keeping the area of earthworks to a minimum and implementing progressive stabilisation to exposed earthworks. Avoidance of overland flow paths and limit areas of work within floodplains where practicable. Protection and stabilisation of steep slopes using clean water diversion bunds. Stabilisation of exposed surface areas as soon as practicable. This may include the application of a layer of geofabrics (for example Bidim) over an unstabilised area or other temporary stabilising method. Installation of down gradient perimeter or diversion controls around and within the construction area to retain and direct sediment laden runoff and prevent contamination of the existing stormwater system and receiving environment. Employ sediment retention devices around and within the construction area to capture and treat as required. This includes a combination of the following: • •

• •

Use of silt fences around the construction area as required to trap sediment laden runoff. Adoption of specific construction practices within the construction area to minimise sedimentation generation during trenching.

All sediment laden runoff captured within the works area shall be transported to a containerised settlement tank unit or the water treatment area located within the CSA. Experienced and trained contractors in construction, operation and maintenance of erosion and sediment control are required, so that the appropriate level of experience and supervision is available to conform to GD05. Continual updates to the ESCP to suit site adjustments. Regular inspections, monitoring and maintenance of the erosion and sediment control measures is required.

3.2 Erosion and Sediment Control Measures 3.2.1. General ESC Measures Erosion and sediment control (ESC) measures will be installed by the construction team prior to the start of site set up or earthworks. The mitigation measures will remain in place until reinstatement of active working areas is complete. ESC measures identified in Table 3-1 can be implemented Page 18

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Erosion and Sediment Control Plan throughout the construction area. All ESC measures shall be designed and maintained in accordance with GD05 (refer to Appendix C1.0 of GD05 for the ESC construction quality checklists). Table 3-1 General erosion and sediment control measures

ESCM

Application

Catchpit/ Stormwater inlet protection

•

Chemical Treatment

•

Chemical treatment can be used to improve the efficiency of sediment retention devices. This treatment requires monitoring and maintenance as spills of reagents can have significant adverse effects on the receiving environment. Following the determination of the effectiveness of treatment, using a “bench test”, the treatment will be provided for sediment retention and dewatering devices. The option of automated or manual dosing will be defined depending on the device and location. For further details refer to the FTMP attached as Appendix C of this ESCP.

Dewatering

•

Dewatering devices will be used to pump out any water that collects within open trenches or excavation areas or for sediment control devices for maintenance. A minimum of 100mm water clarity is required for discharge outside of the works area. The water shall be pumped to settlement tanks or be transported to the water treatment area for treatment. Refer to the Groundwater and Settlement Monitoring and Contingency Plan (GSMCP) for further detail on groundwater levels within the main works area.

•

• • Diversion channel/bund

• • •

Filter socks (with or without flocculation)

• • • •

Cover catchpit grates and inlets with geotextile to filter sediment laden runoff before discharge into the stormwater network; or Other proprietary catchpit protection systems, such as silt/filter sock, sand logs, coir logs and hay bales.

Install to divert runoff from external catchments entering construction areas or for conveyance of sediment laden runoff within construction areas. Hotmix diversion bunds can be used where kerb and channels have been removed or on impervious surfaces. Diversion bunds must have sufficient capacity to carry the flow safely in accordance with GD05 (refer specific calculations for the works involved in section 3.3.6 of this ESCP). Filter socks can be used to intercept and impound runoff before it enters a catchpit or other stormwater inlets. Filter socks can be used to reduce the velocity of runoff flows within a channel, as a check dam. Contain and impound discharges from small volumes of pumped stormwater or concrete wash water (as a turkey nest to promote settlement but cannot be used as means of pH treatment). Filter socks can include flocculation chemicals for additional treatment.

Sand logs/coir logs

•

Use in carriageway to divert clean water from construction site where there is steep terrain uphill or unfavourable carriageway crossfall.

Settlement Tanks

•

Settlement tank units will be used around the site for storage and treatment of sediment-laden runoff. Settlement tank minimum sizing is based upon 2% of the exposed area. Water quality standards must be met before discharging to an existing stormwater inlet, where by pH ranges is between 5.5 to 8.5 and clarity is greater than 100mm. If the settlement tanks become full, or water quality discharge standards cannot be met, the sediment-laden runoff will be transported to the water treatment system for further treatment.

• • •

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Erosion and Sediment Control Plan ESCM

Application

Stabilised entrance and surface

• • • •

•

Install at egress points for construction outside of the carriageway. Vehicle movements within the CSA will remain on sealed surfaces, and any movements within the ACZ areas are to be on sealed surfaces where practicable. Any sediment will be kept within the site, any leaving sediment to be swept back in, and the vehicle access will be swept clean at end of each day. If vehicle access cannot be kept clean by sweeping, water will be used to clean the area around the vehicle access. The dirty water will be directed into a collection sump or an excavated area and then pumped to settlement tank or be transported to the water treatment area. During wet weather conditions, access points are to be carefully monitored and controlled to mitigate sediment / mud leaving the site.

3.2.2. Erosion and Sediment Source Control The erosion and sediment source control measures listed in Table 3-2 have been identified as applicable to all of the main works area. These areas include the ACZ and CSA identified in sections 2.1.1 and 2.1.2 of this ESCP. Table 3-2 General source control measures applicable to the works area for elimination and/or minimisation of erosion and sediment generation

Source/Activity

Source Control Measure

General site management

• • •

Soil Management & Stockpiles

• • • • • •

• • Sediment transport due to runoff from external catchments entering the construction site

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• •

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Minimise works within overland flow paths and floodplains as much as practicable. Check the weather forecast and plan works accordingly if there is to be heavy rainfall/wind. Prior to heavy rainfall, cover site materials and exposed areas with geotextile. A surge pile is planned to be located within the CSA to allow for temporary storage of spoil from the construction works. Avoid stockpiling of soil and spoil on site on ACZs if practicable. Any temporary stockpiles of excavated or construction materials will not exceed 24m3 of spoil at any one time in each ACZ. Stockpiles are to be in construction areas serviced by ESC measures only. Topsoil and spoil should be stockpiled separately. Stockpiles will be managed to prevent sediment runoff by applying one or more of the following measures: 1. Use of covers 2. Light compaction of stockpile surfaces 3. Light wetting for dust suppression (wetting must not result in runoff) 4. Bunding. All stockpiles within the ACZ shall be covered at the end of each day and during periods of heavy rain. Refer to the Air Quality DWP (AQ DWP) attached in Appendix I of the CEMP for detail on dust management from stockpiles. Construct diversion bunds/channel to divert runoff from external catchments entering land disturbance sites. Use clean water diversions (e.g. sandbags, compacted earth, bund) where there is steep terrain uphill of the works area to reduce the volume of water requiring management.

Erosion and Sediment Control Plan Source/Activity

Source Control Measure

Sediment transport due to runoff within site

• • •

Open trench work

• •

Erosion due to runoff travelling over reinstated ground

•

Manage the vehicle movements within the site to stay on stabilised surfaces. Regularly sweep or remove any accumulated sediment associated with the works. Dampen dusty exposed working areas to minimise wind distribution of sediments. Cut and cover methodology shall be adopted. Backfill and compact trenches as soon as possible in an immediate and progressive manner. Dewatering of trenches and/or excavations must be pumped to a sediment retention device (settlement unit or onsite water treatment area) for treatment. Do not remove ESC measures until the reinstatement of active working areas is established.

3.2.3. Asphalt Works and Concrete Pumping / Pouring The environmental risk of concrete or asphalt works is high. The majority of the existing catchpits will be abandoned or relocated during the early works phase. The catchpits proposed to be abandoned and relocated are shown in the ESCP drawings in Appendix B of this ESCP. Runoff generated from concrete or asphalt works is highly alkaline, so must be contained and tested for pH and then associated treatment, before discharging into the surrounding environment. Other recommended controls are: • Delay asphalt / concreting works when heavy rain is forecast, if practicable. • Minimise the volume of water used on site (e.g. in dust suppression, concrete cutting) so there is less to control. • Dust is created during dry concrete or asphalt cutting. Use saws that can cut with water and provide slurry control to collect all concrete or asphalt contaminated material. • If the above is not practical, divert all runoff to the construction pit/ trench or unsealed ground, away from surface water and overland flow paths. All captured runoff will be pumped to the settlement tanks or the water treatment area for treatment of pH, and, if the treated runoff does not comply with the water quality discharge standards, the discharge will be disposed offsite to a licensed treatment facility, in accordance with A2N consent condition 145. (refer to Auckland Council Best Management Practice, Concrete and Asphalt, Auckland Council, July 2015). • Wash all equipment and tools in a designated wash area. • Do not allow concrete trucks or concrete pumpers to wash out on site unless there is a designated wash area with capture and treatment systems in place. • Use polythene or drip trays or equivalent under concrete pumps and delivery chutes to capture any spills.

3.3 Specific Erosion and Sediment Control Measures 3.3.1. Aotea Station Foundations The Aotea Station foundation works include excavations and installation of the piling and D-wall construction. The exposed works area during this phase is provided in Table 3-3. Page 21

| Aotea Station Main Works

Erosion and Sediment Control Plan Table 3-3 Approximate length of trench open per week for the Aotea Station foundation works

D-wall Piling

Approx. installed wall width (trench width will be greater) 1m 1.5m

Approx. length of trench worked per week 40m 20m

The following ESC measures will be implemented during this phase of the works: • •

• •

Diversion bund to divert clean water away from the construction zone to a stormwater inlet and dirty water to a settlement tank. The dirty water diversion bunds will divert general gravity runoff to a low point collection sump (indicative location shown in Appendix B drawings of this ESCP) which then will be pumped to settlement tank(s) for treatment. The collection sump and settlement tank locations displayed in the ESCP drawings are indicative and will ultimately be determined by the Link Alliance and, depending on site conditions and as works progress, locations may change accordingly. Any sediment-laden water dewatered from the excavations will be pumped into a settlement tank or the water treatment area for treatment and/or disposal. Stabilised entrance will be provided at any truck entrance/exit locations where practicable. Vehicle access to the site will be restricted to construction delivery and service vehicles, which minimises the transport of sediment across the site.

3.3.2. Aotea Station Construction The station construction will concurrently occur: •

On the southern section: “top down” construction methodology of a solid slab cast in situ roof structure will happen in stages. The roof slab will have holes to allow extraction and loading in of spoil and construction materials, while excavation to the final depth occurs concurrently under the roof. The methodology will minimise the area of exposed earthworks. • On the northern section: the northern running tunnels will be constructed by “bottom up” methodology, which consists of excavations to build the tunnels. Section 2.3 of the CEMP provides details of the Aotea Station main works construction methodology. The following ESC measures will be implemented during this phase of the works: • •

• •

Page 22

Diversion bund to divert clean water away from the construction zone to a stormwater inlet and dirty water to a settlement tank. The dirty water diversion bunds will divert general gravity runoff to a low point collection sump (indicative location shown in Appendix B drawings of this ESCP) which then will be pumped to settlement tank for treatment. The settlement tank locations displayed in the drawings are indicative and will ultimately be determined by the Link Alliance, and depending on site conditions and as works progress, locations may change accordingly. Any sediment-laden water dewatered from the excavations will be pumped into a settlement tank or the water treatment area for treatment and/or disposal. Stabilised entrance will be provided at any truck entrance/exit locations where practicable. Vehicle access to the site will be restricted to construction delivery and service vehicles, which minimises the transport of sediment across the site. | Aotea Station Main Works

Erosion and Sediment Control Plan

3.3.3. Aotea Station MEFH installation and structural fitout There are no earthworks involved in this phase of the construction, therefore no ESC measures are required.

3.3.4. CSA The Aotea Station CSA at Bledisloe carpark will be established during the Aotea Station early works (the Stage 4 and 5 works, also referred to as Phase 2 of the Aotea Station works) and will be operational during the main works. The earthworks volumes involved in the CSA are relatively small. However, it is to be noted that the most important concern for the CSA is the use of chemicals and related processes associated with plant operations, which will need to be carefully controlled to prevent discharge of contaminants into the receiving environment. The following ESC measures will be implemented during the works at the CSA: • •

•

• • •

Diversion bund to divert clean water away from the construction zone to a stormwater inlet and dirty water to a settlement tank. The dirty water diversion bunds will divert general gravity runoff to a low point collection sump (indicative location shown in Appendix B drawings of this ESCP) which then will be pumped to settlement tank for treatment. The settlement tank locations displayed in the drawings are indicative and will ultimately be determined by the Link Alliance construction team on site, as works progress locations may change accordingly. Due to the plant operations within the CSA, all sediment laden water captured within the site will be diverted and pumped into a water treatment system located within the CSA for testing and treatment or disposal. For high risk of spill areas (i.e. bentonite plant, jet grouting) refer to ESC measures detailed in section 3.4.1 of this ESCP. For stockpiling, refer to ESC measures detailed in section 3.3.5 of this ESCP. Stabilised entrance will be provided at any truck entrance/exit locations where practicable. Vehicle movements within the CSA will be on sealed ground, and vehicle access will be restricted to construction delivery and service vehicles, which minimises the transport of sediment across the site.

3.3.5. Stockpiling A surge pile is planned to be located within the CSA to allow for temporary storage of spoil from the construction works. Spoil will then be transported offsite. A temporary retaining wall and bund will be built to form the surge pile. General soil management and stockpiling ESC measures described in section 3.2.2 of this ESCP will apply. Any standing water captured within the bund will be pumped/transported to the water treatment area or absorbed by the spoil already in the pile.

3.3.6. Settlement tank volumes The general methodologies for sediment-laden runoff are to divert to a collection sump (indicative location shown in Appendix B drawings of this ESCP) or dewater from excavations, then the captured runoff is pumped to a settlement tank or transported to the water treatment area for treatment prior to discharge to the stormwater system. Page 23

| Aotea Station Main Works

Erosion and Sediment Control Plan Indicative settlement tank volumes are listed in Table 3-4, and the actual volumes required will be ultimately determined by the following factors: • It is unlikely that the entire catchment of the site will be destabilised at any one time. Any clean and stabilised areas can be diverted offsite without requiring treatment. • The settlement tank units will be sized based on the open excavation area at any one time, the contributing catchment area in Table 3-4 is only indicative and subject to change. • The groundwater inflow rate is estimated to be in the range of 8 – 16.7m3/day (for 100 m length of trench)2 for the duration of the works (approximately four years) and this is described in section 2.4 of this ESCP. • Rainfall runoff volume within the site is estimated in Table 3-4 for the 20 year ARI design event using a 24 hour rainfall depth of 145 mm (TP1083 24hr rainfall depth chart), not taking into account climate change. More conservative rainfall events can be used to size the settlement tanks based on the site conditions at the time of construction, subject to any potential adverse weather forecast. • The pump size and flow rate. Table 3-4 Settlement tank sizing and water inflow rates for each type of the construction work

Construction works

Contributing Catchment Area (m2)*

Settlement Tank Volume required (m3)**

20 year ARI 24 hour Rainfall Runoff Volume (m3/day)

Approximate length of trench (m)*

Groundwater inflow range (m3/day)*** (based on the 2016 PDP report)

D-wall construction Pilings

0.5

1.7 – 3.5

4.5

0.1

4.5

0.4 – 0.8

Jet grouting

Top-down construction within station roof in Southern section Construction along Northern area of station Aotea Station CSA

1,500

210

4.8 – 10.1

1,500

210

4.8 – 10.1

1,000

140

General Note: Table to be read in conjunction with text from section 3.3.6 of this ESCP. * Contributing catchment area and approximate length of trench is based on the area of earthworks that will be open and worked on at any one time, the areas and trench lengths are conservatively provided at the time and are subject to change. ** Minimum volume for settlement retention device has been calculated using 2% of the contributing catchment area given for each type of work described (in accordance with resource consent condition 168). *** Please refer to the 2016 PDP Groundwater Technical Report2 for the groundwater water inflow volumes.

Guidelines for stormwater runoff modelling in the Auckland Region TP 108, Auckland Council, April 1999 Page 24 | Aotea Station Main Works

Erosion and Sediment Control Plan

3.3.7. Water Treatment Chemical treatment may be required during construction and this can be provided in the containerised settlement tanks, which may include a chemical treatment unit. The water treatment system is a settlement-based treatment system that will be located within the CSA (indicative location south of the proposed station box), refer to ESCP drawings in Appendix B of this ESCP. The system will include chemical treatment capability to assist the settlement process when required. A FTMP is provided in Appendix C of this ESCP and outlines the following: • • • •

Soil testing Chemical dosing options Storage and handling of chemicals Responsibilities for the operation and maintenance of the water treatment system.

3.4 Contaminated Flows Management The Aotea Station main works have the potential to generate contaminated runoff from either existing contaminated soil, contaminated groundwater, elevated pH of groundwater/runoff, or contaminants utilised by construction activities. Where water quality discharge standards for stormwater cannot be met, the following will be applied, in accordance with A2N consent condition 145: Any perched groundwater, or surface run-off water, encountered within the excavation area requiring removal shall be considered as potentially contaminated, and shall either: a. Be disposed of by a licensed liquid waste contractor; or b. Pumped to sewer, providing relevant permits are obtained; or c. Discharged to the stormwater system, provided testing demonstrates compliance with 50 times the Australian and New Zealand Environment Conservation Council (ANZECC) Guidelines for Fresh and Marine Water Quality (2000) for the protection of 95 percent of marine water species, and is free from petroleum hydrocarbons.

3.4.1. High Risk Spillage Areas The CSA has several high-risk spillage areas which include: • The bentonite treatment plant, located at the eastern corner of the CSA; and • D-wall treatment (such as jet grouting plant). Areas around these activities will have a containment bund/barrier as appropriate to prevent any spillages escaping from the site. The containment bund will include collection sump(s), any collected contaminated fluids will be pumped to the water treatment system for treatment, and any treated runoff will be tested, and if the water quality discharge standard cannot be met the fluid will be disposed offsite. Refer to the Industrial and Trade Activities Environmental Management Plan (ITA EMP) provided at Appendix Q to the CEMP for more detail on the management of the above construction activities. Concrete production works are not described in this section as previously outlined in section 3.2.3.

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Erosion and Sediment Control Plan

3.4.2. Other sources of contaminated flows Based on the Contamination Delivery Work Plan (CDWP) attached in Appendix O of the CEMP, initial site investigations have not found any significant in-situ soil contamination within the works area. Should any unforeseen contamination be encountered, this will be addressed in accordance with the CDWP, and any contaminated flows will be transported to the designated water treatment area within the CSA for treatment, and tested for compliance with water quality discharge standards before discharge (refer consent condition 145). Where the contaminated flows cannot be controlled to a standard that allows discharge to stormwater, these flows will be collected and disposed of by a licenced liquid waste contractor or discharged in accordance with the Trade Waste Permit (once obtained).

3.5 Monitoring During Construction All site-specific ESC measures will be inspected on a weekly basis and after rainfall events by the construction team. Inspection will include, but will not be limited to, the requirements outlined in Table 3-5. Monitoring will occur for the full duration of the works, this will ensure that all of the control measures detailed in this ESCP have been properly implemented and are functioning effectively. The monitoring of the performance of the chemical treatment and the degree of flocculation required within the settlement tank units and the water treatment system, are discussed further in the FTMP attached in Appendix C of this ESCP. Table 3-5 Monitoring requirements for ESC

Erosion and Sediment Control

Inspection/Maintenance Requirements

Frequency

Seven day weather forecast

•

Works will be programmed in accordance with weather predictions (refer Metservice 3 Day rain forecast and 7 days weather forecast).

Daily

Catchpit / Stormwater Inlet Protection

•

Check for damage, blockages and leaks – repair immediately. Remove accumulated sediment immediately.

Daily, before & after rainfall

Check for scour and areas where a breach may or has occurred – repair immediately. Remove sediment build up deposited in the dirty water diversion channel. Check for low spots, formation of gullies or debris – repair immediately.

Weekly & after rainfall

• Clean & Dirty Water Diversion Bunds and Channels

• • •

Settlement Tanks

•

Check if the tank is full, and transport sediment-laden runoff to the water treatment system when the tank is nearly full. Monitor frequently to check if the tanks are sized properly, and upgrade if required.

Weekly & after rainfall

Drains and sumps / pumps

•

Visual check that drains and pumps are not blocked and are operating satisfactorily.

Daily & after rainfall

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Erosion and Sediment Control

Inspection/Maintenance Requirements

Frequency

Concrete and Asphalt works

•

Make sure the rate of flow of diverted or wash water does not exceed the ground’s soakage capacity, and clean up any fines or solids left after the water has soaked into the ground. Regularly check that drain plugs, enclosure, sandbags or bunds are in place and are working effectively.

At least once daily

Check quantity of aggregate and geotextile for sediment build up and deterioration – apply more aggregate as required. Check aggregate thickness and if not to GD05 specification then apply more aggregates or change as required. Clean up spilled ground material during truck filling and wash entrances if required.

Daily & after rainfall

•

Stabilised Entranceway and Surface

•

• •

Influent water quality entering the settlement tank units and water treatment system

Details provided in the FTMP (provided in Appendix C)

Refer to FTMP

Effluent water quality exiting the settlement tank units and water treatment system

Details provided in the FTMP (provided in Appendix C)

Refer to FTMP

Application of chemical treatment

If assisted settlement is required using nonchemical or chemical coagulants/flocculants, monitoring of dosing rates will be required. Details provided in the FTMP (provided in Appendix C)

Refer to FTMP

3.6 Heavy Rainfall Response and Contingency Measures The Aotea Station main works are planned to extend over approximately 45 months, approximately between April 2020 to December 2023. High intensity rainfall events can occur during the summer months as well as prolonged rain events during winter months. The Link Alliance will monitor weather forecasts, inspect all ESC measures for adequacy, and undertake any remedial works required prior to forecasted rain events.

3.7 Other Environmental Management Considerations 3.7.1. Dust Control Land disturbance activities shall be undertaken in accordance with the Air Quality (AQ) DWP (Appendix I to the CEMP) in order to minimise the potential for dust generation. Various sections of this ESCP refer to dust management measures from the AQ DWP to be applied to reduce dust and sediment generation during the Aotea Station main works.

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Erosion and Sediment Control Plan

3.8 Site Reinstatement Progressive stabilisation of the exposed work areas shall be carried out as soon as practicable, to minimise the exposed work area to a minimum. All active work areas shall be permanently stabilised against erosion once the associated works are completed. Decommissioning of ESC measures shall only occur once the active works areas are permanently stabilised. Due care will be taken during the removal process so as not to mobilise any sediment.

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Erosion and Sediment Control Plan

4. Roles and Responsibilities, Training and Complaints Response 4.1 Roles and Responsibilities The key management roles in relation to environmental management during construction are outlined in the CEMP. However, all site personnel will be responsible for following the requirements of this ESCP during the main works.

4.2 Training All site staff will undergo general environmental awareness training and training about their responsibilities relating to this ESCP. Training requirements are described in detail in the CEMP. Specific training requirements relating to this ESCP are outlined in Table 4-1. Table 4-1 ESCP training requirements

Training requirements

Frequency

Attendance

ESCP requirements and resource consent conditions

As required and during new staff induction

All new site staff

Tool box meetings on site to include ESC as a standard agenda item

Weekly tool box meetings, or as required (e.g. start of new substantial activity)

All site staff

Construction, maintenance and inspections of ESC devices

As required

Site supervisors and staff site with ESC management responsibilities

4.3 Complaints Any complaints received during the Aotea Station main works shall be recorded and promptly investigated to identify and resolve the cause of the complaint in accordance with the complaints response protocol detailed in the Communication and Consultation Plan (refer Appendix G of the CEMP).

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Erosion and Sediment Control Plan

Appendix A: ISCA Requirements Table A identifies the ISCA Credit Requirements relevant to this ESCP and where they are addressed in the ESCP. Further details regarding the specifics of the evaluation and means of achieving the relevant targets is provided in the relevant sub-plans and other relevant documents. Table A: ISCA Requirements Credit

Relevant section of the ESCP

Requirement *

Other Relevant Information / Comments

Receiving Water Quality DIS-1 Level 1

Measures to minimise adverse impacts to receiving wai environmental values during construction and operation have been identified and implemented. These measures demonstrate an awareness of the values of wai ora and its Mauri, and opportunity for mana whenua feedback has been provided and where practicable incorporated into these measures. AND Monitoring of wai discharges and receiving wai is undertaken at appropriate intervals and at times of discharge during construction.

Section 3.2, 3.3 and 3.5

Also refer to the Emergency Spill Response Plan, Contamination Delivery Work Plan, Groundwater and Settlement Monitoring and Contingency Plan, Industrial Trade and Activities Environmental Management Plan and Flocculant Treatment Management Plan

DIS-2 Level 2

Monitoring and modelling of wai discharges and receiving wai demonstrates no adverse impact on receiving wai environmental values. The infrastructure does not increase peak stormwater flows for rainfall events of up to a 1.5 year ARI event discharge

Section 3.3 and 3.4.

Also refer to the Industrial Trade and Activities Environmental Management Plan and Flocculant Treatment Management Plan

DIS-3 Level 3

Opportunities to improve receiving wai environmental values have been identified and implemented. Monitoring and modelling demonstrates improvement of receiving wai environmental values

Section 3.

Also refer to the Sustainability Management Plan, Industrial Trade and Activities Environmental Management Plan and Flocculant Treatment Plan

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

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Erosion and Sediment Control Plan

Appendix B: ESCP Drawings

Page 31

| Aotea Station Main Works

SW SW

DESIGNATION BOUNDARY

ISO A1 594mm x 841mm

LEGEND:

D - WALL

CONSTRUCTION SUPPORT AREA (CSA) SW

ACTIVE CONSTRUCTION ZONE (ACZ)

SW SW

CLEAN WATER DIVERSION

OVERLAND FLOW DIRECTION SW INLET PROTECTION SW

SETTLEMENT TANK

COLLECTION SUMP SW X

UTILITIES LEGEND: SW

EXISTING STORMWATER

BLUESTONE WALL (NOT PART OF AOTEA MAIN WORKS)

EXISTING SW MANHOLE EXISTING CATCHPIT TO REMAIN

SW SW

EXISTING CATCHPIT TO BE ABANDONED

21.

22.0

.0 X

ALBERT STREET

Last saved by: PERRY.KOSTANICH(2019-12-20) Last Plotted: 2019-12-20 Filename: AECOM_DS10_AU\Documents\60604837-CRL C3-Alliance Detail Design\DesignJV\900 CAD-GIS\01_WIP\25-SKETCHES\CRL-AOT-RME-LKA-SKE-000014

CONTINUATION - REFER TO SKE-000015

C2 WORKS

VICTORIA STREET WEST

SW SW SW

SW SW

PHASE 3 / PHASE 4 CONSTRUCTION -NORTHERN SECTION

NOTES:

12.5 m

FUTURE KINGSTON STREET PLENUM

6.25

1:250

KINGSTON STREET

SW SW SW SW SW SW

Link Alliance has prepared this document for the sole use of the client and for a specific purpose, each as expressly stated in the document. No other third party should rely on this document without the written consent of Link Alliance. Link Alliance undertakes no duty, nor accepts any responsibility, to any third party who may rely upon or use this document.

CREATOR ID : CRL_AOT__00_LKA_SKE_000014

100mm

SIZE A1

FOR INFORMATION APPROVED

DRAWN

FOR CONSENTING PURPOSES DESCRIPTION

E. CHANG

09/12/2019

CHECKED

DATE

C. SECRETIN

09/12/2019

This drawing is confidential and shall only be used for the purpose of this project. The signing of this title block confirms the design and drafting of this project have been prepared and checked in accordance with the Link Alliance quality assurance system to ISO 9001-2000.

DRAWINGS SHALL BE READ IN CONJUNCTION WITH AOTEA MAIN WORKS ESCP AND CEMP.

ALL AREAS ARE INDICATIVE ONLY.

DUE TO STAGING, EXCAVATION SEQUENCE AND METHODOLOGY STILL TO BE DETERMINED, COLLECTION SUMP AND SETTLEMENT TANK LOCATION(S) TO BE DETERMINED BY THE CONSTRUCTION STAFF AND ARE LIKELY TO MOVE AS WORKS PROCEEDS.

THE MAJORITY OF THE EXISTING STORMWATER CATCHPITS WILL BE ABANDONED OR RELOCATED DURING THE EARLY WORKS PHASE, ANY THAT ARE REMAINING WITHIN OR IMMEDIATELY DOWNSTREAM OF THE CONSTRUCTION WORKS SHOULD BE PROTECTED ACCORDING TO GUIDELINE DOCUMENT 005.

CITY RAIL LINK AOTEA STATION

TITLE:

APPROVED

FOR EROSION AND SEDIMENT CONTROL MEASURE STANDARD DETAILS REFER TO GUIDELINE DOCUMENT 005.

ZONE:

D. ROLLO

P. KOSTANICH

PROJECT:

E. CHANG

REV

COMPANY NUMBER : 6267870

SCALE AS SHOWN

DESIGNED REVISIONS

CLIENT:

DIRTY WATER DIVERSION INDICATIVE PUMP FLOW DIRECTION

SW SW SW

> > >

SEDIMENT-LADEN RUNOFF TO BE DIRECTED TO THE COLLECTION SUMP, THEN TO BE PUMPED TO THE SETTLEMENT TANK OR WATER TREATMENT AREA FOR TREATMENT

ESCP LEGEND:

DURHAM STREET WEST

WYNDHAM STREET

BORED PILES

EROSION AND SEDIMENT CONTROL AOTEA MAIN WORKS STAGE 1 - SHEET 1 OF 2 PROJECT

DOCUMENT:

ZONE

DISCIPLINE

ORGANISTION

TYPE

SHEET

CRL - AOT - RME - LKA - SKE - 000014

REVISION

21.

BORED PILES

ESCP LEGEND:

CLEAN WATER DIVERSION DIRTY WATER DIVERSION SW

> > >

22.0

INDICATIVE PUMP FLOW DIRECTION

OVERLAND FLOW DIRECTION SW INLET PROTECTION SW

SW SW

D - WALL

WELLESLEY STREET WEST

CONSTRUCTION SUPPORT AREA (CSA)

ACTIVE CONSTRUCTION ZONE (ACZ) SW

DESIGNATION BOUNDARY

ISO A1 594mm x 841mm

20.

FUTURE WELLESLEY STREET WEST ENTRANCE

LEGEND:

REFER TO LAYOUT DRAWING No. CRL-AOT-RME-LKA-SKE-000027

SEDIMENT-LADEN RUNOFF TO BE DIRECTED TO THE COLLECTION SUMP, THEN TO BE PUMPED TO THE SETTLEMENT TANK OR WATER TREATMENT AREA FOR TREATMENT

UTILITIES LEGEND: EXISTING STORMWATER

EXISTING SW MANHOLE

SITE COMPOUND

EXISTING CATCHPIT TO REMAIN SW

SEDIMENT-LADEN RUNOFF TO BE DIRECTED TO THE COLLECTION SUMP, THEN TO BE PUMPED TO THE SETTLEMENT TANK OR WATER TREATMENT AREA FOR TREATMENT

23.0

CLEAN WATER DIVERSION TO DISCHARGE TO KERB AND CHANNEL

SW SW

SETTLEMENT TANK COLLECTION SUMP

EXISTING CATCHPIT TO BE ABANDONED SW SW SW

24.0 SW

IVE SW

.0 24

26.0

25 .

MYERS STREET

SW SW

27.0

SW SW SW

SW SW

CONTINUATION - REFER TO SKE-000014

25.0 SW SW

MAYORAL DR

SW SW

NOTES:

FOR EROSION AND SEDIMENT CONTROL MEASURE STANDARD DETAILS REFER TO GUIDELINE DOCUMENT 005.

DRAWINGS SHALL BE READ IN CONJUNCTION WITH AOTEA MAIN WORKS ESCP AND CEMP.

SW SW

SW SW SW SW

12.5 m

1:250

CREATOR ID : CRL_AOT__00_LKA_SKE_000015 70

100mm

SIZE A1

FOR INFORMATION APPROVED

DRAWN

FOR CONSENTING PURPOSES DESCRIPTION

E. CHANG

09/12/2019

CHECKED

DATE

C. SECRETIN

09/12/2019

CITY RAIL LINK AOTEA STATION

TITLE:

APPROVED

ZONE:

D. ROLLO

P. KOSTANICH

ALL AREAS ARE INDICATIVE ONLY.

PROJECT:

E. CHANG

REV

COMPANY NUMBER : 6267870

SCALE AS SHOWN

DESIGNED REVISIONS

CLIENT:

6.25

SW SW

PHASE 3 / PHASE 4 CONSTRUCTION SOUTHERN SECTION

EROSION AND SEDIMENT CONTROL AOTEA MAIN WORKS STAGE 1 - SHEET 2 OF 2 PROJECT

DOCUMENT:

ZONE

DISCIPLINE

ORGANISTION

TYPE

SHEET

CRL - AOT - RME - LKA - SKE - 000015

REVISION

ACTIVE CONSTRUCTION ZONE (ACZ) CONSTRUCTION SUPPORT AREA (CSA)

DESIGNATION BOUNDARY 19.0

ISO A1 594mm x 841mm

18.0

LEGEND:

D - WALL SW

DIRTY WATER DIVERSION INDICATIVE PUMP FLOW DIRECTION

OVERLAND FLOW DIRECTION SW INLET PROTECTION

SETTLEMENT TANK

COLLECTION SUMP

EXISTING STORMWATER

EXISTING SW MANHOLE

225Ø UNKNOWN SW SW SW

SW SW

24.0

SW SW

ALBERT STREET SW

25.0

24 .0

ALBERT STREET

225Ø UNKNOWN

CONTINUATION - REFER TO SKE-000017

EXISTING CATCHPIT TO REMAIN EXISTING CATCHPIT TO BE ABANDONED

UTILITIES LEGEND:

SEDIMENT-LADEN RUNOFF TO BE DIRECTED TO THE COLLECTION SUMP, THEN TO BE PUMPED TO THE SETTLEMENT TANK OR WATER TREATMENT AREA FOR TREATMENT

CLEAN WATER DIVERSION

> > >

22.0

DURHAM STREET WEST

ESCP LEGEND:

FUTURE VICTORIA STREET WEST EASTERN ENTRANCE

21.0

20.0

BORED PILES

SW SW SW SW SW

SW SW

6.25

12.5 m

1:250

CREATOR ID : CRL_AOT__00_LKA_SKE_000016 70

100mm

SIZE A1

FOR INFORMATION

FOR EROSION AND SEDIMENT CONTROL MEASURE STANDARD DETAILS REFER TO GUIDELINE DOCUMENT 005.

DRAWINGS SHALL BE READ IN CONJUNCTION WITH AOTEA MAIN WORKS ESCP AND CEMP.

APPROVED

DRAWN

FOR CONSENTING PURPOSES DESCRIPTION

ALL AREAS ARE INDICATIVE ONLY.

CITY RAIL LINK

ZONE:

AOTEA STATION

D. ROLLO

TITLE:

P. KOSTANICH A

PROJECT:

E. CHANG

REV

COMPANY NUMBER : 6267870

SCALE AS SHOWN

DESIGNED REVISIONS

CLIENT:

1. SW

KINGSTON STREET

SW SW SW

SW SW SW SW SW

NOTES:

28.0

27.0

26.0

VICTORIA STREET WEST

PHASE 3 / PHASE 4 CONSTRUCTION -NORTHERN SECTION

E. CHANG

09/12/2019

CHECKED

DATE

APPROVED

DATE

C. SECRETIN

09/12/2019

EROSION AND SEDIMENT CONTROL AOTEA MAIN WORKS STAGE 2 - SHEET 1 OF 2 PROJECT

DOCUMENT:

ZONE

DISCIPLINE

ORGANISTION

TYPE

SHEET

CRL - AOT - RME - LKA - SKE - 000016

REVISION

21. 0

WELLESLEY STREET WEST

CONSTRUCTION SUPPORT AREA (CSA) SW

D - WALL BORED PILES

22.0 SW

ESCP LEGEND:

> > >

CLEAN WATER DIVERSION DIRTY WATER DIVERSION INDICATIVE PUMP FLOW DIRECTION

OVERLAND FLOW DIRECTION SW INLET PROTECTION

SW SW

23.0

ACTIVE CONSTRUCTION ZONE (ACZ) SW

DESIGNATION BOUNDARY

SW SW

ISO A1 594mm x 841mm

LEGEND: SW

FUTURE WELLESLEY STREET WEST ENTRANCE

REFER TO LAYOUT DRAWING No. CRL-AOT-RME-LKA-SKE-000027

SEDIMENT-LADEN RUNOFF TO BE DIRECTED TO THE COLLECTION SUMP, THEN TO BE PUMPED TO THE SETTLEMENT TANK OR WATER TREATMENT AREA FOR TREATMENT

SETTLEMENT TANK

UTILITIES LEGEND:

SITE COMPOUND

COLLECTION SUMP

EXISTING STORMWATER

24.0 SW

EXISTING SW MANHOLE

EXISTING CATCHPIT TO REMAIN EXISTING CATCHPIT TO BE ABANDONED

.0 24

26.0

IVE SW

25 .0

ALBERT STREET

CONTINUATION - REFER TO SKE-000016

25.0 SW SW

MAYORAL DR

27.0

SW SW

PHASE 3 / PHASE 4 CONSTRUCTION SOUTHERN SECTION

SW SW

CREATOR ID : CRL_AOT__00_LKA_SKE_000017 70

100mm

SCALE

SIZE

AS SHOWN

DESIGNED

FOR INFORMATION

DRAWINGS SHALL BE READ IN CONJUNCTION WITH AOTEA MAIN WORKS ESCP AND CEMP.

ALL AREAS ARE INDICATIVE ONLY.

APPROVED

PROJECT:

CITY RAIL LINK

ZONE:

AOTEA STATION

E. CHANG DRAWN

D. ROLLO

TITLE:

P. KOSTANICH A REV

COMPANY NUMBER : 6267870

FOR EROSION AND SEDIMENT CONTROL MEASURE STANDARD DETAILS REFER TO GUIDELINE DOCUMENT 005.

SW SW

1:250

CLIENT:

1. SW

SW SW SW

12.5 m

6.25

NOTES:

FOR CONSENTING PURPOSES DESCRIPTION

E. CHANG

09/12/2019

CHECKED

DATE

APPROVED

DATE

C. SECRETIN

09/12/2019

EROSION AND SEDIMENT CONTROL AOTEA MAIN WORKS STAGE 2 - SHEET 2 OF 2 PROJECT

DOCUMENT:

ZONE

DISCIPLINE

ORGANISTION

TYPE

SHEET

CRL - AOT - RME - LKA - SKE - 000017

REVISION

DESIGNATION BOUNDARY

ISO A1 594mm x 841mm

LEGEND:

ACTIVE CONSTRUCTION ZONE (ACZ)

CONSTRUCTION SUPPORT AREA (CSA) D - WALL

SW SW

> > >

CLEAN WATER DIVERSION DIRTY WATER DIVERSION INDICATIVE PUMP FLOW DIRECTION

OVERLAND FLOW DIRECTION SW INLET PROTECTION SETTLEMENT TANK COLLECTION SUMP

UTILITIES LEGEND: BLUESTONE WALL (NOT PART OF AOTEA MAIN WORKS)

SEDIMENT-LADEN RUNOFF TO BE DIRECTED TO THE COLLECTION SUMP, THEN TO BE PUMPED TO THE SETTLEMENT TANK OR WATER TREATMENT AREA FOR TREATMENT

ESCP LEGEND:

DURHAM STREET WEST

WYNDHAM STREET

BORED PILES

EXISTING STORMWATER

EXISTING SW MANHOLE EXISTING CATCHPIT TO REMAIN

SW SW

CONTINUATION - REFER TO SKE-000019

21.

22.0

.0 SW

ALBERT STREET

C2 WORKS

EXISTING CATCHPIT TO BE ABANDONED

12.5 m

FUTURE KINGSTON STREET PLENUM

6.25

1:250

NOTES:

KINGSTON STREET

SW SW

SW SW SW

SW SW SW SW SW SW SW SW

PHASE 3 / PHASE 4 / PHASE 5 CONSTRUCTION -NORTHERN SECTION

CREATOR ID : CRL_AOT__00_LKA_SKE_000018

100mm

SIZE A1

FOR INFORMATION APPROVED

DRAWN

FOR CONSENTING PURPOSES DESCRIPTION

E. CHANG

09/12/2019

CHECKED

DATE

C. SECRETIN

09/12/2019

DRAWINGS SHALL BE READ IN CONJUNCTION WITH AOTEA MAIN WORKS ESCP AND CEMP.

ALL AREAS ARE INDICATIVE ONLY.

CITY RAIL LINK AOTEA STATION

TITLE:

APPROVED

ZONE:

D. ROLLO

P. KOSTANICH

FOR EROSION AND SEDIMENT CONTROL MEASURE STANDARD DETAILS REFER TO GUIDELINE DOCUMENT 005.

PROJECT:

E. CHANG

REV

COMPANY NUMBER : 6267870

SCALE AS SHOWN

DESIGNED REVISIONS

CLIENT:

EROSION AND SEDIMENT CONTROL AOTEA MAIN WORKS STAGE 3 - SHEET 1 OF 3 PROJECT

DOCUMENT:

ZONE

DISCIPLINE

ORGANISTION

TYPE

SHEET

CRL - AOT - RME - LKA - SKE - 000018

REVISION

SW SW

DESIGNATION BOUNDARY SW SW

SW SW

ALBERT STREET SW

24.0

SW SW

EXISTING STORMWATER

EXISTING SW MANHOLE EXISTING CATCHPIT TO REMAIN

X SW

22.0

WELLESLEY STREET WEST

SW SW SW SW

25.0

EXISTING CATCHPIT TO BE ABANDONED

27.0

21.0

UTILITIES LEGEND:

26.0

SW SW SW

20.0

SETTLEMENT TANK COLLECTION SUMP

25.0

DIRTY WATER DIVERSION INDICATIVE PUMP FLOW DIRECTION

OVERLAND FLOW DIRECTION

FUTURE VICTORIA STREET WEST EASTERN ENTRANCE CLEAN WATER DIVERSION PIPE TO BE DIRECTED ACROSS WORK SITE TO DISCHARGE TO THE KERB AND CHANNEL

CLEAN WATER DIVERSION

SW INLET PROTECTION

24.0

> > >

23.0

19.0

ESCP LEGEND:

22.0

18.0

BORED PILES

21.0

D - WALL

CONTINUATION - REFER TO SKE-000020

CONTINUATION - REFER TO SKE-000018

CONSTRUCTION SUPPORT AREA (CSA) 20.0

SEDIMENT-LADEN RUNOFF TO BE DIRECTED TO THE COLLECTION SUMP, THEN TO BE PUMPED TO THE SETTLEMENT TANK OR WATER TREATMENT AREA FOR TREATMENT

24 .

SW SW

26.0

ACTIVE CONSTRUCTION ZONE (ACZ)

SW SW

VICTORIA STREET WEST

ISO A1 594mm x 841mm

LEGEND:

27.0

28.0

SW SW

W SSW

m 1:400

CREATOR ID : CRL_AOT__00_LKA_SCH_000019 70

100mm

SIZE A1

FOR INFORMATION

DRAWINGS SHALL BE READ IN CONJUNCTION WITH AOTEA MAIN WORKS ESCP AND CEMP.

APPROVED

DRAWN

FOR CONSENTING PURPOSES DESCRIPTION

E. CHANG

09/12/2019

CHECKED

DATE

C. SECRETIN

09/12/2019

CITY RAIL LINK AOTEA STATION

TITLE:

APPROVED

ALL AREAS ARE INDICATIVE ONLY.

ZONE:

D. ROLLO

P. KOSTANICH

PROJECT:

E. CHANG

REV

COMPANY NUMBER : 6267870

SCALE AS SHOWN

DESIGNED REVISIONS

CLIENT:

FOR EROSION AND SEDIMENT CONTROL MEASURE STANDARD DETAILS REFER TO GUIDELINE DOCUMENT 005.

1. SW

29.0

NOTES:

EROSION AND SEDIMENT CONTROL AOTEA MAIN WORKS STAGE 3 - SHEET 2 OF 3 PROJECT

DOCUMENT:

ZONE

DISCIPLINE

ORGANISTION

TYPE

SHEET

CRL - AOT - RME - LKA - SCH - 000019

REVISION

SW SW

INDICATIVE PUMP FLOW DIRECTION

SW SW

DIRTY WATER DIVERSION SW

CLEAN WATER DIVERSION SW

> > >

21.

ESCP LEGEND:

WELLESLEY STREET WEST

BORED PILES SW

CONSTRUCTION SUPPORT AREA (CSA) D - WALL SW

ACTIVE CONSTRUCTION ZONE (ACZ)

SEDIMENT-LADEN RUNOFF TO BE DIRECTED TO THE COLLECTION SUMP, THEN TO BE PUMPED TO THE SETTLEMENT TANK OR WATER TREATMENT AREA FOR TREATMENT

DESIGNATION BOUNDARY

REFER TO LAYOUT DRAWING No. CRL-AOT-RME-LKA-SKE-000027

LEGEND: 20. 0

ISO A1 594mm x 841mm

OVERLAND FLOW DIRECTION

22.0

SW INLET PROTECTION

SETTLEMENT TANK

SW SW

EXISTING CATCHPIT TO REMAIN

SW SW

EXISTING CATCHPIT TO BE ABANDONED SW

SITE COMPOUND SW

EXISTING STORMWATER

EXISTING SW MANHOLE

23.0

UTILITIES LEGEND: SW

SW SW

COLLECTION SUMP

MYERS STREET

SW SW SW

CONTINUATION - REFER TO SKE-000019

. 24

MAYORAL DR

IVE

26.0

ALBERT STREET

CLEAN WATER DISCHARGE TO PROPOSED KERB AND CHANNEL

25.0 SW SW

SW SW

24.0

FUTURE WELLESLEY STREET ENTRANCE

27.0

SW SW

NOTES:

PHASE 4 / PHASE 5 CONSTRUCTION SOUTHERN SECTION

FOR EROSION AND SEDIMENT CONTROL MEASURE STANDARD DETAILS REFER TO GUIDELINE DOCUMENT 005.

DRAWINGS SHALL BE READ IN CONJUNCTION WITH AOTEA MAIN WORKS ESCP AND CEMP.

SW SW

REVISIONS 0

100mm

SIZE A1

FOR INFORMATION APPROVED

PROJECT:

CITY RAIL LINK

ZONE:

AOTEA STATION

E. CHANG DRAWN

D. ROLLO

TITLE:

P. KOSTANICH A

FOR CONSENTING PURPOSES DESCRIPTION

E. CHANG

09/12/2019

CHECKED

DATE

APPROVED

DATE

C. SECRETIN

09/12/2019

CREATOR ID : CRL_AOT__00_LKA_SKE_000020

SCALE AS SHOWN

DESIGNED

REV

COMPANY NUMBER : 6267870

12.5 m

CLIENT:

6.25

1:250

ALL AREAS ARE INDICATIVE ONLY.

EROSION AND SEDIMENT CONTROL AOTEA MAIN WORKS STAGE 3 - SHEET 3 OF 3 PROJECT

DOCUMENT:

ZONE

DISCIPLINE

ORGANISTION

TYPE

SHEET

CRL - AOT - RME - LKA - SKE - 000020

REVISION

ISO A1 594mm x 841mm

LEGEND:

DESIGNATION BOUNDARY

ACTIVE CONSTRUCTION ZONE (ACZ)

CONSTRUCTION SUPPORT AREA (CSA)

D - WALL

SW SW

ESCP LEGEND:

> > >

CLEAN WATER DIVERSION DIRTY WATER DIVERSION INDICATIVE PUMP FLOW DIRECTION

OVERLAND FLOW DIRECTION SW INLET PROTECTION SETTLEMENT TANK COLLECTION SUMP

UTILITIES LEGEND: BLUESTONE WALL (NOT PART OF AOTEA MAIN WORKS)

SEDIMENT-LADEN RUNOFF TO BE DIRECTED TO THE COLLECTION SUMP, THEN TO BE PUMPED TO THE SETTLEMENT TANK OR WATER TREATMENT AREA FOR TREATMENT

DURHAM STREET WEST

WYNDHAM STREET

BORED PILES

EXISTING STORMWATER

EXISTING SW MANHOLE SW

SW SW

21.

22.0

.0 X

ALBERT STREET

CONTINUATION - REFER TO SKE-000022

C2 WORKS

EXISTING CATCHPIT TO REMAIN EXISTING CATCHPIT TO BE ABANDONED

SW SW

FUTURE KINGSTON STREET PLENUM

12.5 m

NOTES:

6.25

KINGSTON STREET

PHASE 3 / PHASE 4 / PHASE 5 CONSTRUCTION -NORTHERN SECTION

1:250

CREATOR ID : CRL_AOT__00_LKA_SKE_000021

100mm

SIZE A1

FOR INFORMATION APPROVED

DRAWN

FOR CONSENTING PURPOSES DESCRIPTION

E. CHANG

09/12/2019

CHECKED

DATE

C. SECRETIN

09/12/2019

DRAWINGS SHALL BE READ IN CONJUNCTION WITH AOTEA MAIN WORKS ESCP AND CEMP.

ALL AREAS ARE INDICATIVE ONLY.

CITY RAIL LINK AOTEA STATION

TITLE:

APPROVED

ZONE:

D. ROLLO

P. KOSTANICH

FOR EROSION AND SEDIMENT CONTROL MEASURE STANDARD DETAILS REFER TO GUIDELINE DOCUMENT 005.

PROJECT:

E. CHANG

REV

COMPANY NUMBER : 6267870

SCALE AS SHOWN

DESIGNED REVISIONS

CLIENT:

EROSION AND SEDIMENT CONTROL AOTEA MAIN WORKS STAGE 4 - SHEET 1 OF 3 PROJECT

DOCUMENT:

ZONE

DISCIPLINE

ORGANISTION

TYPE

SHEET

CRL - AOT - RME - LKA - SKE - 000021

REVISION

ISO A1 594mm x 841mm

SW SW

LEGEND:

SW SW

DESIGNATION BOUNDARY

CONSTRUCTION SUPPORT AREA (CSA)

ACTIVE CONSTRUCTION ZONE (ACZ)

ESCP LEGEND: SW

> > >

SW SW

COLLECTION SUMP

SW INLET PROTECTION SETTLEMENT TANK

SW SW

DIRTY WATER DIVERSION INDICATIVE PUMP FLOW DIRECTION

21.0

UTILITIES LEGEND:

18.0

CLEAN WATER DIVERSION

OVERLAND FLOW DIRECTION

20.0

VICTORIA STREET WEST

BORED PILES

EXISTING STORMWATER

D - WALL

EXISTING SW MANHOLE

19.0 22.0

SW SW

EXISTING CATCHPIT TO REMAIN EXISTING CATCHPIT TO BE ABANDONED

SW X

22.0

SW SW SW

SW SW

225Ø UNKNOWN

24.0

SW SW

26.0

SW SW SW

SW SW

27.0

CLEAN WATER DIVERSION PIPE TO BE DIRECTED TO THE KERB AND CHANNEL ON ALBERT STREET

28.0

29.0

WELLESLEY STREET WEST

25.0

PHASE 4 / PHASE 5 CONSTRUCTION

CONTINUATION - REFER TO SKE-000023

CONTINUATION - REFER TO SKE-000021

CLEAN WATER TO DISCHARGE TO KERB AND CHANNEL

27.0

CLEAN WATER DIVERSION PIPE TO BE DIRECTED ACROSS WORK SITE TO THE KERB AND CHANNEL

26.0

ALBERT STREET

25.0

23 225Ø UNKNOWN

21.0

SEDIMENT-LADEN RUNOFF TO BE DIRECTED TO THE COLLECTION SUMP, THEN TO BE PUMPED TO THE SETTLEMENT TANK OR WATER TREATMENT AREA FOR TREATMENT

24.0

20.0

23.0

FUTURE VICTORIA STREET WEST EASTERN ENTRANCE

NOTES:

m SW

1:400 SW

REVISIONS 10

100mm

CREATOR ID : CRL_AOT__00_LKA_SKE_000022

SIZE

DESIGNED

FOR INFORMATION

DRAWN

APPROVED

FOR CONSENTING PURPOSES DESCRIPTION

E. CHANG

09/12/2019

CHECKED

DATE

C. SECRETIN

09/12/2019

ALL AREAS ARE INDICATIVE ONLY.

CITY RAIL LINK AOTEA STATION

TITLE:

APPROVED

DRAWINGS SHALL BE READ IN CONJUNCTION WITH AOTEA MAIN WORKS ESCP AND CEMP.

ZONE:

D. ROLLO

P. KOSTANICH A

PROJECT:

E. CHANG

REV

COMPANY NUMBER : 6267870

SCALE AS SHOWN

FOR EROSION AND SEDIMENT CONTROL MEASURE STANDARD DETAILS REFER TO GUIDELINE DOCUMENT 005.

CLIENT:

EROSION AND SEDIMENT CONTROL AOTEA MAIN WORKS STAGE 4 - SHEET 2 OF 3 PROJECT

DOCUMENT:

ZONE

DISCIPLINE

ORGANISTION

TYPE

SHEET

CRL - AOT - RME - LKA - SKE - 000022

REVISION

ISO A1 594mm x 841mm

LEGEND:

SW SW

DESIGNATION BOUNDARY

ESCP LEGEND: SW

> > >

21. 0

DIRTY WATER DIVERSION INDICATIVE PUMP FLOW DIRECTION

OVERLAND FLOW DIRECTION

SW INLET PROTECTION SW

SETTLEMENT TANK

CLEAN WATER DIVERSION

BORED PILES

D - WALL

CONSTRUCTION SUPPORT AREA (CSA)

REFER TO LAYOUT DRAWING No. CRL-AOT-RME-LKA-SKE-000027

SEDIMENT-LADEN RUNOFF TO BE DIRECTED TO THE COLLECTION SUMP, THEN TO BE PUMPED TO THE SETTLEMENT TANK OR WATER TREATMENT AREA FOR TREATMENT

ACTIVE CONSTRUCTION ZONE (ACZ) 20. 0

WELLESLEY STREET WEST

COLLECTION SUMP SW

22.0 SW

UTILITIES LEGEND: SW SW

SW SW SW

SITE COMPOUND SW

MYERS STREET

SW SW

EXISTING CATCHPIT TO BE ABANDONED

24.0

EXISTING SW MANHOLE

23.0

FUTURE WELLESLEY STREET WEST ENTRANCE

26.0

ORA

L DR

MAY

IVE

ALBERT STREET

. 24

CONTINUATION - REFER TO SKE-000022

25.0 SW SW

CLEAN WATER DISCHARGE TO PROPOSED KERB AND CHANNEL

.0 24

SW SW

27.0

SW SW

NOTES:

SW SW

FOR EROSION AND SEDIMENT CONTROL MEASURE STANDARD DETAILS REFER TO GUIDELINE DOCUMENT 005.

DRAWINGS SHALL BE READ IN CONJUNCTION WITH AOTEA MAIN WORKS ESCP AND CEMP.

PHASE 4 / PHASE 5 CONSTRUCTION SOUTHERN SECTION

ALL AREAS ARE INDICATIVE ONLY.

6.25

12.5 m

0 1:250

SW SW

CREATOR ID : CRL_AOT__00_LKA_SKE_000023

100mm

SIZE A1

FOR INFORMATION APPROVED

PROJECT:

CITY RAIL LINK

ZONE:

AOTEA STATION

E. CHANG DRAWN

D. ROLLO

TITLE:

P. KOSTANICH A REV

COMPANY NUMBER : 6267870

SCALE AS SHOWN

DESIGNED REVISIONS

CLIENT:

EXISTING STORMWATER

EXISTING CATCHPIT TO REMAIN

SW SW

FOR CONSENTING PURPOSES DESCRIPTION

E. CHANG

09/12/2019

CHECKED

DATE

APPROVED

DATE

C. SECRETIN

09/12/2019

EROSION AND SEDIMENT CONTROL AOTEA MAIN WORKS STAGE 4 - SHEET 3 OF 3 PROJECT

DOCUMENT:

ZONE

DISCIPLINE

ORGANISTION

TYPE

SHEET

CRL - AOT - RME - LKA - SKE - 000023

REVISION

ISO A1 594mm x 841mm

LEGEND:

DESIGNATION BOUNDARY

ACTIVE CONSTRUCTION ZONE (ACZ)

CONSTRUCTION SUPPORT AREA (CSA)

D - WALL

SW SW

ESCP LEGEND:

> > >

CLEAN WATER DIVERSION DIRTY WATER DIVERSION INDICATIVE PUMP FLOW DIRECTION

OVERLAND FLOW DIRECTION SW INLET PROTECTION SETTLEMENT TANK COLLECTION SUMP

UTILITIES LEGEND: BLUESTONE WALL (NOT PART OF AOTEA MAIN WORKS)

SEDIMENT-LADEN RUNOFF TO BE DIRECTED TO THE COLLECTION SUMP, THEN TO BE PUMPED TO THE SETTLEMENT TANK OR WATER TREATMENT AREA FOR TREATMENT

DURHAM STREET WEST

WYNDHAM STREET

BORED PILES

EXISTING STORMWATER

EXISTING SW MANHOLE SW

EXISTING CATCHPIT TO REMAIN

SW SW

21.

22.0

ALBERT STREET

CONTINUATION - REFER TO SKE-000025

C2 WORKS

EXISTING CATCHPIT TO BE ABANDONED

SW SW

FUTURE KINGSTON STREET PLENUM

12.5 m SW

6.25

1:250

NOTES:

KINGSTON STREET

PHASE 4 / PHASE 5 CONSTRUCTION -NORTHERN SECTION

CREATOR ID : CRL_AOT__00_LKA_SKE_000024

100mm

SIZE A1

FOR INFORMATION APPROVED

DRAWN

FOR CONSENTING PURPOSES DESCRIPTION

E. CHANG

09/12/2019

CHECKED

DATE

C. SECRETIN

09/12/2019

DRAWINGS SHALL BE READ IN CONJUNCTION WITH AOTEA MAIN WORKS ESCP AND CEMP.

ALL AREAS ARE INDICATIVE ONLY.

CITY RAIL LINK AOTEA STATION

TITLE:

APPROVED

ZONE:

D. ROLLO

P. KOSTANICH

FOR EROSION AND SEDIMENT CONTROL MEASURE STANDARD DETAILS REFER TO GUIDELINE DOCUMENT 005.

PROJECT:

E. CHANG

REV

COMPANY NUMBER : 6267870

SCALE AS SHOWN

DESIGNED REVISIONS

CLIENT:

EROSION AND SEDIMENT CONTROL AOTEA MAIN WORKS STAGE 5 - SHEET 1 OF 3 PROJECT

DOCUMENT:

ZONE

DISCIPLINE

ORGANISTION

TYPE

SHEET

CRL - AOT - RME - LKA - SKE - 000024

REVISION

ISO A1 594mm x 841mm

SW SW

LEGEND:

SW SW

DESIGNATION BOUNDARY

CONSTRUCTION SUPPORT AREA (CSA)

ACTIVE CONSTRUCTION ZONE (ACZ)

ESCP LEGEND: SW

> > >

SW SW

COLLECTION SUMP

SW INLET PROTECTION SETTLEMENT TANK

SW SW

DIRTY WATER DIVERSION INDICATIVE PUMP FLOW DIRECTION

21.0

UTILITIES LEGEND:

18.0

CLEAN WATER DIVERSION

OVERLAND FLOW DIRECTION

20.0

VICTORIA STREET WEST

BORED PILES

EXISTING STORMWATER

D - WALL

EXISTING SW MANHOLE

19.0 22.0

SW SW

EXISTING CATCHPIT TO REMAIN EXISTING CATCHPIT TO BE ABANDONED

22.0

CONTINUATION - REFER TO SKE-000024

SW SW

225Ø UNKNOWN

24.0

SW SW

26.0

25.0

ALBERT STREET

23 225Ø UNKNOWN

27.0

SW SW

26.0

NOTES:

SW SW SW

SW SW

27.0

WELLESLEY STREET WEST

25.0

CLEAN WATER TO DISCHARGE TO KERB AND CHANNEL

PHASE 4 / PHASE 5 CONSTRUCTION

CONTINUATION - REFER TO SKE-000026

SW X

SW SW

21.0

SEDIMENT-LADEN RUNOFF TO BE DIRECTED TO THE COLLECTION SUMP, THEN TO BE PUMPED TO THE SETTLEMENT TANK OR WATER TREATMENT AREA FOR TREATMENT

24.0

20.0

23.0

FUTURE VICTORIA STREET WEST EASTERN ENTRANCE

28.0

FOR EROSION AND SEDIMENT CONTROL MEASURE STANDARD DETAILS REFER TO GUIDELINE DOCUMENT 005.

DRAWINGS SHALL BE READ IN CONJUNCTION WITH AOTEA MAIN WORKS ESCP AND CEMP.

ALL AREAS ARE INDICATIVE ONLY.

29.0

m SW

1:400 SW

REVISIONS 10

100mm

CREATOR ID : CRL_AOT__00_LKA_SKE_000025

SIZE

DESIGNED

FOR INFORMATION APPROVED

PROJECT:

CITY RAIL LINK

ZONE:

AOTEA STATION

E. CHANG DRAWN

D. ROLLO

TITLE:

P. KOSTANICH A REV

COMPANY NUMBER : 6267870

SCALE AS SHOWN

CLIENT:

FOR CONSENTING PURPOSES DESCRIPTION

E. CHANG

09/12/2019

CHECKED

DATE

APPROVED

DATE

C. SECRETIN

09/12/2019

EROSION AND SEDIMENT CONTROL AOTEA MAIN WORKS STAGE 5 - SHEET 2 OF 3 PROJECT

DOCUMENT:

ZONE

DISCIPLINE

ORGANISTION

TYPE

SHEET

CRL - AOT - RME - LKA - SKE - 000025

REVISION

ISO A1 594mm x 841mm

LEGEND:

SW SW

DESIGNATION BOUNDARY

ESCP LEGEND: SW

> > >

DIRTY WATER DIVERSION INDICATIVE PUMP FLOW DIRECTION

OVERLAND FLOW DIRECTION

21. 0

SW INLET PROTECTION SW

SETTLEMENT TANK

CLEAN WATER DIVERSION

BORED PILES

SEDIMENT-LADEN RUNOFF TO BE DIRECTED TO THE COLLECTION SUMP, THEN TO BE PUMPED TO THE SETTLEMENT TANK OR WATER TREATMENT AREA FOR TREATMENT

CONSTRUCTION SUPPORT AREA (CSA) D - WALL

REFER TO LAYOUT DRAWING No. CRL-AOT-RME-LKA-SKE-000027

ACTIVE CONSTRUCTION ZONE (ACZ) 20. 0

WELLESLEY STREET WEST

COLLECTION SUMP SW

22.0 SW

UTILITIES LEGEND: SW SW

SW SW SW

SITE COMPOUND SW

MYERS STREET

SW SW

EXISTING CATCHPIT TO BE ABANDONED

24.0

EXISTING SW MANHOLE

23.0

FUTURE WELLESLEY STREET WEST ENTRANCE

. 24

26.0

RAL

MAY O

ALBERT STREET

DRI

CLEAN WATER DISCHARGE TO PROPOSED KERB AND CHANNEL

25.0 SW SW

CONTINUATION - REFER TO SKE-000025

EXISTING STORMWATER

EXISTING CATCHPIT TO REMAIN

SW SW

.0 24

SW SW

27.0

SW SW

NOTES:

FOR EROSION AND SEDIMENT CONTROL MEASURE STANDARD DETAILS REFER TO GUIDELINE DOCUMENT 005.

DRAWINGS SHALL BE READ IN CONJUNCTION WITH AOTEA MAIN WORKS ESCP AND CEMP.

1. SW

PHASE 4 / PHASE 5 CONSTRUCTION NORTHERN SECTION

SW SW

ALL AREAS ARE INDICATIVE ONLY.

6.25

12.5 m

0 1:250

SW SW

CREATOR ID : CRL_AOT__00_LKA_SKE_000026

100mm

SIZE A1

FOR INFORMATION APPROVED

PROJECT:

CITY RAIL LINK

ZONE:

AOTEA STATION

E. CHANG DRAWN

D. ROLLO

TITLE:

P. KOSTANICH A REV

COMPANY NUMBER : 6267870

SCALE AS SHOWN

DESIGNED REVISIONS

CLIENT:

FOR CONSENTING PURPOSES DESCRIPTION

E. CHANG

09/12/2019

CHECKED

DATE

APPROVED

DATE

C. SECRETIN

09/12/2019

EROSION AND SEDIMENT CONTROL AOTEA MAIN WORKS STAGE 5 - SHEET 3 OF 3 PROJECT

DOCUMENT:

ZONE

DISCIPLINE

ORGANISTION

TYPE

SHEET

CRL - AOT - RME - LKA - SKE - 000026

REVISION

STORES LOADING AREA

DESIGNATION BOUNDARY CSA BOUNDARY

SW SW

21.

SETTLEMENT TANK

POLYMER STORAGE

COLLECTION SUMP

22.0 MUD

WATER

UTILITIES LEGEND:

MUD LINES (1M WIDE)

INDICATIVE PUMP FLOW DIRECTION

SW SW

MIXER

WORKSHOP

DIRTY WATER DIVERSION

EXISTING STORMWATER

SITE VEHICLE ENTRY ONLY

EXISTING SW MANHOLE

MISSION PUMP

MUD

BENTONITE TANK

EXISTING CATCHPIT TO REMAIN

MISSION PUMP

23.0 SW

TOWER CRANE FOR BUILDING CONSTRUCTION

SITE OFFICES AND WELFARE FACILITIES

EXISTING CATCHPIT TO BE ABANDONED

3 MUD

WELLESLEY STREET WEST

MUD

MISSION PUMP

2 SW

DESANDING PLANT

EMERGENCY ACCESS AREA

TEMPORARY SPOIL PIT

24.0

SPARE

MYERS STREET

Last saved by: PERRY.KOSTANICH(2020-02-19) Last Plotted: 2020-02-19 Filename: AECOM_DS10_AU\Documents\60604837-CRL C3-Alliance Detail Design\DesignJV\900 CAD-GIS\01_WIP\25-SKETCHES\CRL-AOT-RME-LKA-SKE-000027

CWS

CLEAN WATER DIVERSION SW

> > >

ESCP LEGEND:

16 15 14 13 12 11 10

WASTE MANAGEMENT AREA

TRUCK AND TRAILER

STATION ENTRANCE STRUCTURE

VEHICLE ACCESS CONTROL

HAZARDOUS GOODS STORE

BENTONITE SILOS

PEDESTRIAN ACCESS CONTROL

BENTONITE MIXING + PUMPS

LEGEND:

SETTLEMENT TANK TO TREAT THE SEDIMENT-LADEN RUNOFF, OR PUMP TO THE WATER TREATMENT AREA FOR TREATMENT.

STABILISED ENTRY FOR TRUCKS. IT SHOULD BE A MINIMUM 5m IN LENGTH.

ISO A1 594mm x 841mm

SEDIMENT-LADEN RUNOFF TO BE DIRECTED TO THE COLLECTION SUMP, THEN TO BE PUMPED TO THE SETTLEMENT TANK OR WATER TREATMENT AREA FOR TREATMENT

SW SW

D-WALL TREATMENT AREA

26.0

MAYORAL DRIVE

CLEAN WATER DIVERSION TO REMAIN AS KERB AND CHANNEL, TO DIVERT AWAY FROM CSA

25.0

SPARE

LOCATION OF PROPOSED SURGE PILE SURGE PILE

SW SW

.0 24

NOTES:

SITE VEHICLE EXIT

SW SW SW

10m

SIZE A1

REVISIONS Link Alliance has prepared this document for the sole use of the client and for a specific purpose, each as expressly stated in the document. No other third party should rely on this document without the written consent of Link Alliance. Link Alliance undertakes no duty, nor accepts any responsibility, to any third party who may rely upon or use thisCRL_AOT__00_LKA_SKE_000027 document. 30

100mm

FOR INFORMATION APPROVED

FOR INFORMATION DESCRIPTION

ALL AREAS ARE INDICATIVE ONLY.

DUE TO STAGING, EXCAVATION SEQUENCE AND METHODOLOGY STILL TO BE DETERMINED, COLLECTION SUMP AND SETTLEMENT TANK LOCATION(S) TO BE DETERMINED BY THE CONSTRUCTION STAFF AND IS LIKELY TO MOVE AS WORKS PROCEEDS. THE MAJORITY OF THE EXISTING STORMWATER CATCHPITS WILL BE ABANDONED OR RELOCATED DURING THE EARLY WORKS PHASE, ANY THAT IS REMAINING WITHIN OR IMMEDIATELY DOWNSTREAM OF THE CONSTRUCTION WORKS SHOULD BE PROTECTED ACCORDING TO GUIDELINE DOCUMENT 005.

CITY RAIL LINK

ZONE:

AOTEA STATION

D. ROLLO

TITLE:

P. KOSTANICH

REV

PROJECT:

E. CHANG DRAWN

ALL DRAWINGS SHALL BE READ IN CONJUNCTION WITH AOTEA MAIN WORKS ESCP AND CEMP.

SCALE

DESIGNED

IV E

AS SHOWN

CLIENT:

YO R

SCALE 1:250

FOR EROSION AND SEDIMENT CONTROL MEASURE STANDARD DETAILS REFER TO GUIDELINE DOCUMENT 005.

STABILISED ENTRY FOR TRUCKS

EQUIPMENT / PLANT LAYDOWN AREA

SITE VEHICLE ENTRY

2.5

AGGREGATE STORAGE AREA

27.0

HAZARDOUS GOODS STORE

WATER TREATMENT AREA

TBM RETRIEVAL LOCATION

VEHICLE ENTRY & EXIT

LAYDOWN AREA

E. CHANG

29/11/2019

CHECKED

DATE

APPROVED

DATE

C. SECRETIN

29/11/2019

EROSION AND SEDIMENT CONTROL AOTEA MAIN WORKS SHEET 1 OF 1 PROJECT

DOCUMENT:

ZONE

DISCIPLINE

ORGANISTION

TYPE

SHEET

CRL - AOT - RME - LKA - SKE - 000027

REVISION

Erosion and Sediment Control Plan

Appendix C: Flocculant Treatment Management Plan

Page 32

| Aotea Station Main Works

Aotea Station Main Works Flocculant Treatment Management Plan

CRL-AOT-RME-LKA-PLN-800029 Revision: 000 Date: 5 March 2020

Flocculant Treatment Management Plan

Aotea Station Main Works CRL-AOT-RME-LKA-PLN-800029

This document is uncontrolled when printed. This document should be printed in colour

Revision Status Revision 000

Date 05/03/2020

Version details

Prepared By

Approved By

Final for lodgement

Ellen Chang

Peter Roan

Approval Status Name/Title

Signature

Date

Prepared by:

Ellen Chang Graduate Civil Engineer

05/03/2020

Reviewed by:

Caroline Secretin Principal Environmental Scientist

05/03/2020

Approved by:

Duane Rollo Associate Director â€“ Civil Infrastructure

05/03/2020

Authorised by:

Peter Roan Consenting Lead

05/03/2020

Page 2

| Aotea Station Main Works

Flocculant Treatment Management Plan

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

Aotea Station Overview..................................................................................................... 5

1.2

FTMP Staging ..................................................................................................................... 7

1.3

Purpose of the FTMP ......................................................................................................... 7

1.4

FTMP Structure.................................................................................................................. 8

1.5

Relevant Conditions .......................................................................................................... 8

1.6

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

1.7

FTMP Review and updates .............................................................................................. 12

2. Aotea Station Main Works ........................................................................ 13 2.1

Overview of Works .......................................................................................................... 13

2.1.1.

Active Construction Zone .......................................................................................... 13

2.1.2.

Construction Support Area Layout ............................................................................ 13

2.2

Programme ...................................................................................................................... 14

2.3

Construction Methodology .............................................................................................. 14

3. Chemical Treatment System Details ......................................................... 15 3.1

Standards and guidelines documents .............................................................................. 15

3.2

Sediment Retention Devices............................................................................................ 15

3.3

Soil Testing ...................................................................................................................... 15

3.3.1.

Test Procedure ......................................................................................................... 16

3.4

Potential Flocculants and Coagulants .............................................................................. 17

3.5

Dosing Options ................................................................................................................ 17

3.6

Chemical Treatment Performance ................................................................................... 18

4. Storage and Handling of Chemicals .......................................................... 20 5. Emergency and Spillage ............................................................................ 21 6. Responsibility for Operation, Maintenance and Monitoring.................... 22 7. Inspection and Maintenance .................................................................... 23 8. Water Quality Discharge Monitoring Programme .................................... 24

Page 3

8.1

Sampling Locations .......................................................................................................... 24

8.2

Monitoring Parameters ................................................................................................... 24

8.2.1.

Daily ......................................................................................................................... 24

8.2.2.

Weekly ..................................................................................................................... 24

| Aotea Station Main Works

Flocculant Treatment Management Plan 8.3

Monitoring Methods ....................................................................................................... 24

8.3.1.

Daily ......................................................................................................................... 24

8.3.2.

Weekly ..................................................................................................................... 25

8.4

Trigger Levels ................................................................................................................... 25

8.4.1.

Daily Parameters Trigger Levels ................................................................................ 25

8.4.2.

Weekly Parameters .................................................................................................. 26

8.5

Monitoring reports .......................................................................................................... 27

8.5.1.

Initial monitoring report ........................................................................................... 27

8.5.2.

Non-conforming result report................................................................................... 27

8.5.3.

Annual monitoring reports ....................................................................................... 27

Appendix A: ISCA Requirements ..................................................................... 28 Appendix B: Record of CLG Comments ........................................................... 29 Appendix C: Typical Automated Dosing Treatment Unit ................................ 30

Page 4

| Aotea Station Main Works

Flocculant Treatment Management Plan

Figure 1-1 CRL Route and Location

This Flocculant Treatment Management Plan (FTMP) has been prepared in relation to the Aotea Station main construction works and is attached as an Appendix to the Erosion and Sediment Control Plan (ESCP).

Auckland Transport (AT) has obtained a resource consent for an Over Station Development (OSD) on the Bledisloe Car Park site (Council Reference R/LUC/2016/2647). The proposal involves the construction of a 24-level building comprising offices, retail and food and beverage tenancies, and public features including a plaza and a through site link. The proposed OSD is not part of the Link Alliance contract and will be progressed separately by Auckland Council / Panuku. Page 5 | Aotea Station Main Works

Flocculant Treatment Management Plan

Figure 1-2 Indicative Aotea Station indicating length of underground station box with the associated above-ground Main Station structure at Wellesley Street, entrance structures at Victoria Street and the Kingston Street Plenum.

Page 6

| Aotea Station Main Works

Flocculant Treatment Management Plan Given the nature and scale of the Aotea Station construction, works will be undertaken in a staged manner, involving: •

•

Five stages of early works (canopy removal, network utility relocation and site establishment work), being undertaken from October 2019 to March 2020 (Stages 1 to 3) and December 2019 through to August 2020 (Stages 4 and 5); these works have been authorised by separate Outline Plans (Council ref. OPW60345651 and OPW60348747); Main construction works (the ‘Aotea Station main works’) involving construction of the station box, associated above ground structures, mined tunnels for the rail tracks, internal finishings, structural fitout, all Mechanical, Electrical, Fire and Hydraulic (MEFH) installation, and architectural finishings2. The Aotea Station main works will be undertaken from early2020 through to late-2023; and Ground reinstatements (from late-2022) and urban realm improvements. These works will be described in a future Outline Plan2.

Refer to Section 2 of the Construction Environmental Management Plan (CEMP) for a detailed description of the Aotea Station main works.

1.2 FTMP Staging This FTMP addresses the Aotea Station main works, which are detailed in the CEMP, and an overview is provided in section 2 of this FTMP.

1.3 Purpose of the FTMP This FTMP has been prepared to identify measures that will be implemented to enhance the effectiveness of the erosion and sediment control (ESC) measures utilised on site. The objectives of the FTMP are: •

To manage all bulk earthworks to minimise any discharge of debris, soil, sediment or sediment-laden water beyond the site to either land and/or stormwater drainage systems; and

•

To detail how the discharges of water from the site will be monitored to ensure compliance with the above.

This FTMP also includes the Water Quality Discharge Monitoring Programme (WQDMP). This FTMP addresses the requirements of conditions 59 to 64 and 173 to 179 of the CRL regional resource consent (land use consent R/LUC/2016/1890) 3 and will be implemented throughout the construction period. This FTMP forms part of the ESCP, attached as Appendix H to the CEMP, and should be read in conjunction with the ESCP and the other relevant main works Delivery Work Plans (DWP) and Management Plans (MP) required by the designation and resource consent conditions.

Flocculant Treatment Management Plan The FTMP has been developed in consultation with the Aotea Community and Business Liaison Group (CLG) as per resource consent condition 19. A record of the consultation outcomes is provided in Appendix B of this FTMP.

1.4

FTMP Structure

This FTMP is structured as follows: • • •

• • • • •

Section 1 details the project background, outlines the purpose of the FTMP, the scope of the FTMP, and highlights relevant resource consent conditions. Section 2 provides an overview of the works and the construction support area (CSA) site layout. Section 3 describes the use of flocculants and coagulants for chemical treatment and the testing procedure to determine the chemical type and dosage used, and the different dosing options. Section 4 details the storage and handling of chemicals. Section 5 describes the response plan in place for any emergency or spillage of chemicals used during the chemical treatment activities. Section 6 details the implementation and operation of the FTMP and also covers roles, responsibilities and training requirements. Section 7 details the monitoring and maintenance requirements of the flocculation management practise. Section 8 details the water quality discharge monitoring programme, which describes the monitoring parameters, methods, trigger levels and reporting that needs to be implemented during chemical treatment.

1.5

Relevant Conditions

Table 1-1 identifies the resource consent conditions relevant to this FTMP and where they are addressed in the document. Table 1-1 Aotea Station main works FTMP conditions and location in this plan

Condition No.

Condition

Relevant section of FTMP

Specific conditions – land use consent R/LUC/2016/1890 Flocculant treatment management plan 59

At least 20 working days prior to the commencement of construction, the Consent Holder shall submit to Council (Team Leader Central Monitoring) for certification an FTMP which confirms the measures that will be taken to ensure that the construction of the Project or Project Stage will be generally consistent with the Water Quality Assessment and the Industrial and Trade Activities Assessment prepared by Golder Associates (NZ) Limited, both dated December 2014.

This FTMP

The Consent Holder shall request the Council's (Team Leader Central Monitoring) written determination as to whether the FTMP can be certified, in writing, within 10 working days of receipt of the FTMP. No construction activity shall commence until certification from Council is provided.

Noted

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Flocculant Treatment Management Plan

Condition No.

Condition

Relevant section of FTMP

The FTMP shall include, but not be limited to, the following matters:

3, 4, 5, 6 and 8

• Specific design details of the flocculent treatment system based on a batch dosing methodology for the site's settlement tanks, including the potential for use of non -chemical flocculants (e.g. chitin based flocculants); • Monitoring, maintenance (including post-storm) and contingency programme (including a record sheet); • Details of optimum dosage (including assumptions); • Results of initial flocculent treatment trial; • A spill contingency plan; and • Details of the person or bodies who will hold responsibility for the long-term operation and maintenance of the flocculent treatment system and the organisational structure which will support this system. 62

Any change to an FTMP shall be submitted to the Council (Team Leader Central Monitoring) for certification.

1.7

The Consent Holder shall request the Council's (Team Leader Central Monitoring) written determination as to whether the proposed change can be certified, to be provided within 10 working days of submission of the change. No activity reliant upon a change to the FTMP can be undertaken until the change has been certified.

Noted

The Consent Holder shall comply with the ESCP for the duration of the earthworks associated with the Project.

Noted

As Built Certification General Performance Standards The Consent Holder shall ensure that the erosion and sediment control measures are constructed and maintained in accordance with GD05, except where a higher standard is detailed in an ESCP/FTMP, in which case the higher standard shall apply.

3.1 (and ESCP)

Specific conditions – discharge permit (contaminated land) R/REG/2016/1895 and land use consent R/LUC/2016/1890 (Contaminated Land and Resource Management (National Environmental Standard for Assessing and Managing Contaminants in Soil to Protect Human Health) Regulations 2011) Contaminated Soils Management Plan 144

The Consent Holder shall implement the procedures for the management, treatment, temporary containment, testing, and disposal of groundwater and surface run-off water via the stormwater system in accordance with the report titled Auckland City Rail Link: Resource Consent Package 2: Aotea Station to North Auckland Line Construction and CRL Operation: Draft Erosion & Sediment Control Management Plan, dated 13 May 2016, prepared by Aurecon New Zealand Limited, and provided with the application.

3, 7, 8 (and ESCP)

145

145. Any perched groundwater, or surface run-off water, encountered within the excavation area requiring removal shall be considered as potentially contaminated, and shall either:

3.2 and 3.6 (and Industrial and Trade Activities Environmental

a. be disposed of by a licensed liquid waste contractor; or Page 9

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Flocculant Treatment Management Plan

Condition No.

Condition

Relevant section of FTMP

b. pumped to sewer, providing relevant permits are obtained; or c. discharged to the stormwater system, provided testing demonstrates compliance with 50 times the Australian and New Zealand Environment Conservation Council (ANZECC) Guidelines for Fresh and Marine Water Quality (2000) for the protection of 95 percent of marine water species, and is free from petroleum hydrocarbons.

Management Plan - ITA EMP)

Specific conditions – discharge permit (other) R/REG/2016/1896 and discharge permit (ITA) R/REG/2016/1898 (CONSTRUCTION) Structural Controls 169

Noted

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.

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 *Applicable only in discharge from treatment systems in CSA 3 and CSA 4, not applicable to Aotea Station (CSA 1)

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Flocculant Treatment Management Plan

Condition No.

Condition

Relevant section of FTMP

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). 175

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

8 and 8.3

176

Within five working days of receipt of sample results showing contaminants exceeding the agreed trigger levels in Condition 174(d):

8.5.2

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). Discharge Reporting Requirements 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:

8.5.1

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. 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 siteâ€™s environmental performance for the year to date.

8.5.3 (as well as CEMP and 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;

8.5.3 (as well as CEMP and ITA 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 Page 11

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Flocculant Treatment Management Plan

Condition No.

Condition

Relevant section of FTMP

f. records of any spills or incidents which occurred within the previous 12 months and the response which was undertaken.

1.6

Sustainability

The Link Alliance is seeking an Infrastructure Sustainability Council of Australia (ISCA) Infrastructure Sustainability (IS) Rating. Further details can be found in the CEMP and Sustainability Management Plan. Project sustainability requirements that relate directly to this FTMP are included in Appendix A of this FTMP. These requirements are imbedded within this FTMP 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. Further detail on sustainability is provided in section 1.7 of the CEMP.

1.7

FTMP Review and updates

This FTMP is a live document that will be reviewed at least annually, or: • • • •

As a result of a material change to the project, or To address unforeseen water treatment of the groundwater and stormwater arising from construction, or If potential flocculants and coagulants are likely to be used (additional to the one described in the current version of this FTMP), or As a result of unresolved complaints in the project area.

Any material changes to this FTMP must be certified by Auckland Council prior to any on-site activity reliant upon the change commencing (as per conditions 62 and 63 of the CRL Regional resource consent). Refer to the CEMP for further detail on the review and updating process of the Plans.

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Flocculant Treatment Management Plan

2. Aotea Station Main Works 2.1 Overview of Works The Aotea Station main works will involve three main phases of work. Each phase of work involves multiple construction activities which will be undertaken throughout the Aotea project site. The phases associated with the Aotea main works involve: • • •

Foundation works to form the perimeter walls of the station box and underground running tunnels. This involves diaphragm wall construction, roof construction, piling and jet grouting; Construction of the Aotea Station platforms, Wellesley Street entrance structure, concourse, Victoria Street entrance structures and Kingston Street Plenum, and; Structural fitout of the Aotea Station including MEFH installation, and internal and architectural finishings.

The works require the operation of a Construction Support Area (CSA) within the Bledisloe House car park site and a portion of Mayoral Drive. Equipment used to undertake these works will be predominantly situated in the CSA. Upon completion of the Aotea main works, the area will be repurposed in preparation for public realm reinstatement works2. The methodology for the construction of the Aotea Station is predominantly based on a ‘top down’ and ‘bottom up’ approach. The ‘top down’ approach relates to the southern end of Albert Street (south of Durham Street) and involves the installation of the ‘roof structure’ early on, which enables a limited number of traffic lanes to operate concurrently with the construction of the station, which occurs beneath. This approach reduces the construction effects on traffic flow within the city centre. The tunnel alignment on the northern end of Albert Street (north of Durham Street) will be constructed using a ‘bottom up’ methodology. A detailed description of the Aotea main works is included in the CEMP and includes; • • •

2.1.1. Active Construction Zone The Aotea Station main works will be undertaken throughout a work zone referred to as Active Construction Zone (ACZ), in accordance with resource consent. Further detail is provided in section 2.6.1 of the CEMP. Erosion and sediment generation is expected to occur throughout the ACZ during the Aotea Station main works.

Bentonite treatment and jet grouting area; | Aotea Station Main Works

Flocculant Treatment Management Plan • • •

• • • •

600 m3 surge pile (footprint area of 150 m2) located on the south-western corner of the site compound; Bentonite, polymer and material storage; The specifically designated water treatment area will treat dirty runoff, water from within excavations and water from concrete wash-off and runoff collected within the bunds of high risk spillage areas (i.e. bentonite plant and jet grouting area); Main vehicle entrance to the station trench; TBM retrieval locations; Entrance/exit to CSA for trucks (with stabilised entry and exit) through Mayoral Drive; and Entrance/exit to the CSA for service vehicles will be through the eastern side of the CSA.

2.2 Programme The Aotea Station main works are anticipated to take approximately 45 months to complete, occurring from April 2020 to December 2023 (approximately) as detailed in Table 2-1 in Section 2.2 of the CEMP. Some construction activities outlined in each phase of the Aotea Station main works will occur in parallel.

2.3 Construction Methodology The Aotea Station main works will be divided into stages as described in the CEMP.

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Flocculant Treatment Management Plan

Chemical Treatment System Details 3.1 Standards and guidelines documents

The coagulant and flocculant treatment (commonly referred to as flocculation) will be designed, operated and maintained in accordance with Section F2.0 – Coagulant and Flocculant Treatment of Auckland Council Guideline Document 2016/005 (GD05)4 and Auckland Council’s Technical Publication TP227 “The Use of Flocculants and Coagulants to Aid the Settlement of Suspended Sediment in Earthworks Runoff: Trials, Methodology and Design”5.

3.2 Sediment Retention Devices Chemical treatment is expected to be used at sediment retention devices (located within both the ACZ and CSA) specified in the ESCP. The sediment-laden runoff from the excavations will be pumped into the sediment retention devices which will provide simple settlement by default. If simple settlement does not provide the required water discharge quality6 as specified in section 8.4 of this FTMP (in accordance with resource consent condition 145(c)), then assisted settlement via flocculation will be required. Assisted settlement decreases the settlement time by increasing the sediment removal efficiency of the sediment retention devices, therefore, the use of flocculation treatment is to be investigated for all sediment retention devices on site. The following scenarios are where flocculation treatment may not be required: • •

Bench testing of soils in the contributing catchment confirms there is no benefit from flocculation, or The duration of the earthworks is very short.

The details of the specific ESC measures including the sediment retention devices to be utilised in each works area are detailed within the ESCP (and depicted in the ESCP drawing attached as Appendix B of the ESCP).

3.3 Soil Testing Prior to bulk earthworks commencing within the catchment of a settlement device, a ‘bench test’ will be undertaken to assess the effectiveness and type of chemical treatment appropriate for the site’s soils. The bench test involves collecting a sample of the earthworks site’s soils, mixing it with water in a clear cylinder and measuring the settling time of the suspended sediment. Soil samples will be taken

Erosion and Sediment Control Guide for Land Disturbing Activities in the Auckland Region – Guideline document 2016/005 (GD05), Auckland Council, June 2015 5 Auckland Council’s Technical Publication TP227 – The Use of Flocculants and Coagulants to Aid the Settlement of Suspended Sediment in Earthworks Runoff: Trials, Methodology and Design, Auckland Council, June 2014 6 The required groundwater and surface run-off quality to be discharged to stormwater is defined as per resource consent condition 145(c), i.e. provided testing demonstrates compliance with 50 times the Australian and New Zealand Environment Conservation Council (ANZECC) Guidelines for Fresh and Marine Water Quality (2000) for the protection of 95 percent of marine water species, and is free from petroleum hydrocarbons. Section 8.4 of this FTMP provides detail about discharge quality monitoring and trigger levels. Page 15 | Aotea Station Main Works

Flocculant Treatment Management Plan and tested with a variety of flocculants and coagulants to determine reactivity and subsequent improvement in settlement efficiencies.

Figure 3-1 Example of Bench Testing (Source: GD05)

The output of the bench testing is the optimal amount of chemical (mg) to be applied per unit volume of sediment-laden runoff (L), known as the dose (mg/L). The concentration derived from the bench testing is used on site to calibrate the dose rate, which is site specific and dependant on rate and concentration of sediment-laden runoff from the site. The test procedure is further detailed in section 3.3.1 of this FTMP. A bench test is required in the following circumstances: • • • •

For each representative soil type in the catchment contributing to a sediment retention device; Any time batch-dosing is required; Any time chemical treatment is to be considered; Whenever previous chemical treatment is no longer providing adequate results.

Limitations of bench testing include: •

• • •

pH must be tested as part of the bench testing and should be used as a control baseline, any flocculant that is used must not change that baseline pH to beyond +/- 1, and must not fall outside of the pH range 5 – 9. Treatment should cease when the above pH limits cannot be met (when using Polyaluminium Chloride (PAC)). Treatment requires a high degree of monitoring and maintenance. In significant rainfall events (>15mm in 24 hours), the dosing rate needs to be carefully monitored so that the system does not run out of reagent.

3.3.1. Test Procedure Appendix F1.0 of GD05 outlines the required Bench Testing Methodology that will be used to determine the most appropriate dosage rate. The methodology is based on liquid PAC and not applicable to solid flocculants, for advice on testing and using solid flocculants please contact Auckland Council. A summary of GD054 bench testing methodology is provided below: 1. Collect soil sample that is representative of the catchment soil. 2. Testing is undertaken by mixing a representative sample of soil from the site with water to produce a weak slurry, representative of sediment laden runoff from the site. 3. Samples of this are then taken and placed in clear jars along with an additional reference sample. Page 16

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Flocculant Treatment Management Plan 4. Potential chemical additives are then added at varying concentrations (where appropriate). 5. At regular intervals (0 minutes, 30 minutes and 60 minutes), the depth of clarity is measured in each sample to determine which dosage of chemical provides the greatest level of settlement. 6. The pH of each sample is also measured after 60 minutes to ensure that this remains within the required limits of 5 – 9. 7. The turbidity of each sample is also measured after 60 minutes. 8. The most effective dosage rate is compared with the reference sample to assess whether chemical treatment is effective. 9. The appropriate dosage rate is then used to calculate the sizes of the various components of the rainfall activated treatment devices.

3.4 Potential Flocculants and Coagulants A number of potential flocculants and coagulants are available, however experience with the typical soils in the area indicate that the greatest increases in efficiency will be provided by either of: • • • •

Polyaluminium Chloride (PAC) – most commonly used coagulant in NZ PolyDADMAC EC20 (80% PAC / 20% PolyDADMAC) Acid (such as Hydrochloric acid (HCl), citric acid or a similar product), or CO2 injection to reduce pH.

When initial testing is undertaken, an assessment will also be made to determine if the use of nonchemical (i.e. organic) flocculants (e.g. chitin based) will provide suitable increases in efficiency. Note that PAC is the only product that went through rigorous testing by Auckland Council, and that use of other chemicals may require specific approval from Auckland Council. The use of flocculants and coagulants in addition to PAC or PolyDADMAC products can be updated as industry experience advances or if more environmentally friendly options (i.e. organic flocculants) are proposed. However, they can only be utilised upon a revision of this FTMP which will follow the review process described in section 1.7 of this FTMP. Revisions of the FTMP will identify the chemicals, the dosing procedures and testing and sampling proposed to ensure that residual chemicals are monitored and within acceptable limits.

3.5 Dosing Options The following forms of dosing/treatment are expected to be used where assisted settlement is required by way of either automated dosing and/or manual dosing. Dosing types and details are provided in the Table 3-1. Table 3-1 Aotea Station main works dosing options

Dosing type Automated dosing treatment (see Figure 3-2 for a typical system flow chart)

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Description • Fully automated dosing system. • Uses telemetry to monitor and record live updates to maintain pH levels and turbidity on site. • A flow-activated dosing pump which uses coagulants and flocculants to allow for settlement which segregates solids from liquid. • The whole process is monitored through an automatic pH controller.

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Flocculant Treatment Management Plan •

Manual dosing treatment

• • • • •

Recirculation system for re-treatment where the required water quality discharge standard cannot be met. For more details of the system refer to Appendix C of this FTMP. Manual dosing system. Typically undertaken to treat an impounded volume of sediment-laden runoff (i.e. a tank or a pond), typically as a result of pumping. Process where the volume of impounded water is determined and from this the appropriate volume of additive determined, added and mixed. Process can be used where Automated dosing treatment cannot achieve the required water quality discharge standard.

The sampling and testing of soils previously detailed in section 3.3 will be utilised to determine the appropriate chemical and dose rate for the Aotea Station main works. Both dosing treatment types can be used for flocculation treatment and pH adjustment. The dose rate to buffer the pH, and the pH monitoring will be determined by either manual methods (e.g. pH strips) or by a pH sensor, which will sample water within the settlement tank and will be adjusted by the operator as required. Figure 3-2 shows a typical example of an automated dosing treatment unit, refer to Appendix C of this FTMP for the supplier specification of the system.

Figure 3-2 Example of a typical automated dosing treatment unit (Source: Green Technologies Ltd)

3.6 Chemical Treatment Performance The sediment retention devices are expected to achieve required water discharge quality6 of treated water into the receiving environment, in accordance with resource consent condition 145(c) (refer section 8.4 of this FTMP for further detail). In the event that the water discharge quality does not meet the standard required, the following contingency measures will be initiated:

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Flocculant Treatment Management Plan • • •

The water discharge will be recirculated through the water treatment system for further treatment, including manual chemical dosing if required; If excessive water enters the work area during heavy rainfall, the water may be temporarily held within the excavation area until it is processed by a water treatment system; and /or Vacuum trucks could be deployed to convey excess or substandard quality water off-site.

There may be considerations to provide temporary storage tank as part of the water treatment systems.

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4. Storage and Handling of Chemicals The water treatment chemicals will be stored in bunded containers in the vicinity of the water treatment system in order to contain any spillage or failure of container vessels or pipe connections. The storage and monitoring of the chemicals used as part of the water treatment system will be undertaken by trained personnel in accordance with the requirements of the Industrial and Trade Activities Environmental Management Plan (ITA EMP) attached in Appendix Q of the CEMP. These personnel are listed in section 6 of this FTMP. Further detail about hazardous substance is also provided in section 5.15 of the CEMP. Monitoring will ensure all chemicals used on site are accounted for, and the daily volumes used will be captured on the daily record sheets.

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5. Emergency and Spillage Chemical substances will be mainly in liquid form, should the use of chemical treatment be required during the Aotea Station main works. A general Emergency Spill Response Plan (ESRP) has been developed to set out the project spill management procedures. Specific Bentonite ESRP and jet grout ESRP will also be prepared prior to the start of the main works. ESRP are included in Appendices C, D and E of the ITA EMP. It is noted Appendix D (Bentonite Spill Response Plan) and Appendix E (Jet Grout Spill Response Plan) will be prepared and certified prior to the commissioning of these plants. In addition, the following emergency and contingency measures will be in place (refer section 2.6.2.3 of the CEMP): â€˘ â€˘

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The system will be alarmed both in the risk of flooding of the station box (by means of float alarms) and of the sediment retention device. In an overflow situation, actions will include the use of sucker trucks and a metered discharge to the sewer.

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Flocculant Treatment Management Plan

6. Responsibility for Operation, Maintenance and Monitoring The Aotea Station Construction Manager and the Aotea Station Environmental Advisor will be responsible for the implementation of the FTMP, as outlined in Table 6-1. Responsibilities include in particular the operation and maintenance of the treatment system and water quality monitoring. This table needs to be read in conjunction with the roles and responsibilities outlined in section 4.1 of the CEMP. Table 6-1 Responsibilities for implementation of the FTMP

Role • Aotea Station Project Manager

Responsibility • Ensures site personnel adhere to the CEMP and sub-plans (including FTMP) and comply with environmental operating procedures.

• Aotea Station Construction Manager • Aotea Station Environmental Advisor (with support from ESCP/CEMP Subject Matter Expert)

• Project and Site Engineers

• Treatment plant operator • Treatment Unit Supplier personnel • Suppliers / Subcontractors

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• Develops, implements and reviews environmental management systems including the FTMP. • Oversees the water quality discharge monitoring and that sampling is carried out as per sampling protocol. • Reviews water quality monitoring results, investigates and reports to Auckland Council any non-compliances. • Provides on-site compliance with resource consent conditions and other requirements (such as trade waste consent if applicable) and ensure site compliance. • Undertakes regular site inspections and audits to ensure compliance with the CEMP and sub-plans, including the FTMP and consent conditions. • Implements (or supervises subcontractors to ensure implementation of) environmental controls in accordance with the contract, CEMP and sub-plans including FTMP. • Ensures environmental erosion and sediment control works are installed and maintained as per ESCP/FTMP and supplier’s technical specifications. • Manages maintenance and operation of the water treatment system. • Inspects works (such as operation and maintenance of the sediment retention devices and the water treatment system) to assess compliance with the FTMP and other sub-plans. • Is responsible for the implementation of the water quality discharge monitoring programme.

• Undertakes test procedure and bench testing for use of flocculant at the water treatment system.

Flocculant Treatment Management Plan

7. Inspection and Maintenance The inspection and maintenance actions specific to the flocculation management practices are required to be undertaken at specific frequencies, as specified in Table 7-1. This table needs to be read in conjunction with section 3.5 of the ESCP, which details the inspection and maintenance procedures of the ESC measures. Table 7-1 Inspection and maintenance of the water treatment system

Water treatment system Inspection and Maintenance Actions

Inspection and Maintenance Actions Requirements

Frequency

Seven day weather forecast

•

Works will be programmed in accordance with weather predictions (refer Metservice 3 Day rain forecast and 7 days weather forecast).

Daily

Sediment retention device (without chemical treatment)

•

Check if the device is full, and transport sediment-laden runoff to the water treatment system when the tank is nearly full. Monitor frequently to check if the tanks are sized properly, and upgrade if required.

Weekly and after rainfall

Check quantity of coagulants/flocculants that remains in the system – top up the device with more coagulants/flocculants as required. All hoses, connections etc. will be checked to ensure they are working effectively and that there is no leakage. Accumulated sediment should be cleaned out regularly. pH7 of the water treatment system to be monitored daily (refer section 8.3.1) Any changes in degree of stabilisation of the construction site.

Weekly and after rainfall, and when site will be left unattended for more than 48 hours.

• Water treatment system

• • • • •

Note: frequency of this testing may be increased during extended periods of heavy rainfall.

Soil testing (bench testing)

•

Bench test to determine whether chemical treatment is required.

As required, refer section 3.3

Application of Chemical treatment

•

If assisted settlement is required using nonchemical or chemical coagulants/flocculants, monitoring of dosing rates will be required. Water clarity and turbidity monitoring and maintenance through telemetry/live updates (or manually, depending on the method chosen, refer section 3.5).

Daily and after rainfall

•

In addition to the inspection and maintenance actions, monitoring will be undertaken as per the Water Quality Discharge Monitoring Programme (refer section 8 of this FTMP). The results of the daily and weekly sampling will be retained for inspection/review as required.

If the pH levels fall outside the range 5 – 9, the Environmental Advisor will determine appropriate actions which could include decommissioning the flocculation unit or adding alternate chemicals, such as sodium carbonate or sodium bisulphate, to alter the pH. Page 23 | Aotea Station Main Works

Flocculant Treatment Management Plan

8. Water Quality Discharge Monitoring Programme A Water Quality Discharge Monitoring Programme (WQDMP) has been prepared in accordance with the requirements of resource consent condition 1743. It is based on the 2016 Water Quality Assessment Golder Report8 and the ANZECC (2000) guidelines9 where applicable.

8.1 Sampling Locations Typically, the daily and weekly sampling will be undertaken at the outlet of each sediment retention device or the water treatment system, prior to discharging to the stormwater network.

8.2 Monitoring Parameters This section lists the parameters to be analysed as part of the WQDMP.

8.2.1. Daily Daily sampling and measurement will be made of: • • •

Water clarity Turbidity pH

(cm) (NTU)

8.2.2. Weekly Weekly sampling and measurement will be made of: • • • • • •

Total Suspended Solids (TSS) (g/m3) Total recoverable copper (g/m3) Dissolved copper (g/m3) Total recoverable zinc (g/m3) Dissolved zinc (g/m3) Total petroleum hydrocarbons (TPH) (g/m3).

A review of the weekly sampling parameters will be undertaken after eight weeks of sampling based on the testing results (refer section 8.5.1). The WQDMP will be amended accordingly.

8.3 Monitoring Methods This section details the monitoring methods as part of the WQDMP.

8.3.1. Daily The method of daily monitoring will depend on the sediment retention device or the water treatment system utilised. For the majority of devices, the daily monitoring will be undertaken manually with a grab sample taken at the outlet. A summary of the daily monitoring methods is provided in Table 8-1. Automatic sampling methods/telemetry may also be used. 8

Auckland City Rail Link A2N Water Quality Assessment, Golder Associates (NZ) Limited, May 2016. Australian and New Zealand Environment Conservation Council Guidelines for Fresh and Marine Water Quality (ANZECC 2000), 2018 Page 24 | Aotea Station Main Works 9

Flocculant Treatment Management Plan Table 8-1 Daily monitoring (manual) methods

Monitoring parameters Water Clarity pH TPH Turbidity

Details Measured using a secchi disc (30mm diameter), record the depth to the nearest 5mm, to which the disc is no longer visible in the water. Calibrated pH probe. Visual check if presence of conspicuous oil or grease film, sheen or odour. Calibrated turbidity meter.

This monitoring will be recorded on daily record sheets detailing the following information: •

• • • • • •

Visual check of influent and effluent if presence/absence visible TPH (e.g. conspicuous oil or grease film, sheen or odour), flocculant type and volume used, dosing system operation details; Water clarity monitoring; Turbidity monitoring; pH monitoring; Record any notes for maintenance or additional information (e.g. ordering additional flocculant supplies); Record of daily volume of chemicals used; and Record of daily volume of sediment-laden runoff treated.

Following the evaluation of water quality samples collected over the one-month period, the frequency of sampling and parameters analysed will be reviewed and the monitoring programme amended if required.

8.3.2. Weekly Weekly sampling will be undertaken by retrieving a sample(s) of outflows from the lowest stormwater manhole within or immediately below the construction area or CSA. The parameters listed in section 8.2.2 will be analysed for by an accredited laboratory. The treated water samples will be collected on a weekly basis for eight weeks for analysis of water quality. Following the evaluation of water quality samples collected over the eight weeks period, the frequency of sampling and parameters analysed will be reviewed and the monitoring programme amended if required.

8.4 Trigger Levels The initial trigger levels for discharges from the site are provided in the following sections for both daily and weekly monitoring. Process to review trigger levels is also detailed in those sections.

8.4.1. Daily Parameters Trigger Levels Trigger values are provided in the Table 8-2. The initial trigger values are taken from GD054. Soil testing will inform trigger level value to be set for water clarity and turbidity of daily samples. A review of the initial trigger values will be undertaken after one month of sampling based on the results of soil testing. Page 25

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Flocculant Treatment Management Plan Table 8-2 Daily monitoring trigger levels

Chemical / Parameter Water clarity

pH TPH Turbidity

Initial Trigger Value

Notes

Water clarity of 10cm or greater measured with a secchi disc. Between 5 and 9 No visible TPH (sheen or odour) Between 2,000 â€“ 3,000 NTU (From GD054)

Soil testing will inform trigger level value to be set for water clarity of daily samples.

Soil testing will inform trigger level value to be set for turbidity of daily samples.

8.4.2. Weekly Parameters The initial trigger values for the weekly parameters are taken from the 2016 Water Quality Assessment Golder Report8 . These have been based on a 50 dilution factor times the ANZECC(2000)9 guidelines values for 95% level of protection of marine species (the Waitemata Harbour being the receiving environment). After eight weeks of sampling being undertaken, a review of the sampling programme will be carried out and will encompass review of parameters, trigger levels and frequency, and the WQDMP will be amended accordingly where necessary. The review will be summarised in a report submitted to Auckland Council (refer section 8.5.1). Table 8-3 Weekly monitoring trigger values

Chemical / Parameter TSS

ANZECC (2000) 95% level of protection for marine species NA

Initial Trigger Value (Aotea Catchment)*

Notes

50 g/m3 for 95% of samples

Concentrations are managed with a goal of being less than 20 g/m3 for half of the samples. 50 x ANZECC 95% Freshwater (50 times dilution expected)

Total 0.0013 g/m3 0.065 g/m3 Recoverable Copper Dissolved 0.0013 g/m3 0.065 g/m3 Copper Total 0.015 g/m3 0.75 g/m3 Recoverable Zinc Dissolved Zinc 0.015 g/m3 0.75 g/m3 TPH NA 15 g/m3 Auckland Council GD0110 *Trigger levels for heavy metals are based on Golder (2016) and in accordance with resource consent condition 145(c).

Stormwater Management Devices in the Auckland Region â€“ Guideline document 2017/001 (GD01), Auckland Council, December 2017 Page 26 | Aotea Station Main Works

Flocculant Treatment Management Plan

8.5 Monitoring reports 8.5.1. Initial monitoring report Following eight weeks of monitoring commencing the Aotea Station main works, an initial report will be prepared and provided to Auckland Council (Team Leader Central Monitoring), outlining: • • • •

A summary of the monitoring results to date; An interpretation of those results and suggestions for improvement to the site operations where required; A programme for ongoing monitoring including the reporting of results (i.e. any changes to the monitoring programme described in sections 8.1 to 8.5 of this FTMP); and Water treatment system maintenance programme (refer section 7 of this FTMP).

8.5.2. Non-conforming result report Monitoring results will be reviewed at least weekly for analysis of any non-compliances. Within five working days of receipt of sample results showing contaminants exceeding the trigger levels set out in section 8.4 of this FTMP, the following contingency measures will be implemented: • •

An investigation will be undertaken to determine why exceedances were detected and to identify any additional source controls or treatment required; and The results of this investigation will be sent in a report format to Auckland Council (Team Leader Central Monitoring).

8.5.3. Annual monitoring reports An annual report (encompassing CEMP, ITA EMP and FTMP) will be prepared and submitted to Auckland Council (Team Leader Central Monitoring), combining the management plans annual performance and detailing: • • • • • •

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All aspects of the performance of the EMP relating to this consent; A summary of all revisions and revised sections of the EMP; Details of all inspections and maintenance of the stormwater system for the preceding 12 months; Details of and changes to the person(s) or body responsible for the maintenance of site and the organisational structure supporting this process; 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 Records of any spills or incidents which occurred within the previous 12 months and the response which was undertaken.

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Flocculant Treatment Management Plan

Appendix A: ISCA Requirements Table A identifies the ISCA Credit Requirements relevant to this FTMP and where they are addressed in the FTMP. Further details regarding the specifics of the evaluation and means of achieving the relevant targets is provided in the relevant sub-plans and other relevant documents. Table A: ISCA Requirements Credit

Relevant section of the FTMP

Requirement *

Other Relevant Information / Comments

Receiving Water Quality DIS-1 Level 1

Section 8 (and the ESCP)

DIS-3 Level 3

Opportunities to improve receiving wai environmental values have been identified and implemented. Monitoring and modelling demonstrates improvement of receiving wai environmental values

Section 8 (and the ESCP)

Also refer to the Sustainability Management Plan, Industrial Trade and Activities Environmental Management Plan.

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

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Flocculant Treatment Management Plan

Appendix B: Record of CLG Comments CLG An Aotea CLG meeting was held on 19th November to discuss the Aotea Station main works and for the CLG to provide comments / feedback on the CEMP and sub-plans, including this FTMP. No comments were received in relation to this FTMP.

Auckland Council No comment was received from Auckland Council on the FTMP.

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Flocculant Treatment Management Plan

Appendix C: Typical Automated Dosing Treatment Unit

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CWU Concrete Wash Unit

Green1 Technologies have developed a fully automated system to deal with high pH levels in concrete wash from work carried out on construction sites. This system is economical, reliable and uses telemetry to monitor and record live updates to maintain pH levels and turbidity on site. Depending on the system size it can be fully solar powered with 12volt DC battery or run on a normal power supply. THE ENVIRONMENTAL IMPACT OF CEMENT WASH WATER/ PRODUCTS

Concrete wash water is highly toxic to fish and other aquatic wildlife, it can cause damage to vegetation and ecosystems and with prolonged skin contact is capable of causing second degree burns. Sometimes, people refer to concrete wash water as the “silent polluter” with such major environmental impacts. The construction sector in New Zealand has always encouraged the implementation of best environmental practice and has supported this through a lot of “green” initiatives. Our company is providing a solution to one such hazard by the treatment and the disposal of water associated with concreting activities.

BENEFITS: • Eases manpower through automation • Reduces chemical usage for an eco-friendly environment • Affordable with low maintenance cost • Highly accurate and easy data management system • Telemetry provides live data updates accessible anywhere • Can be customised as per requirement

PO Box 2019, Palmerston North, New Zealand Ph. 06 355 0185 E. info@green1.nz

HOW THE SYSTEM WORKS: GREEN1’s concrete wash system unit has been designed to give full control to the user and it allows easy integration of pH monitoring. The unit has a magnetic flow meter on the concrete wash water inlet to detect the flow. A dosing pump uses Polyaluminium Chloride (PAC) to separate the coarse concrete particles and allow them to settle in the filtration tank which has a lamella clarifier segregating solids from liquid which streams to the buffer tank. This process is monitored through an automatic pH controller. The pH monitoring smart system measures pH in the filtration tank and if the pH level rises above 11, it signals the pump to divert the water in the buffer tank and alerts an operator through text message. The pH limit can be adjusted as per requirement. The buffer tank has another pH monitoring system that updates the operator with live data information. Supplementary pH adjustment occurs in the buffer tank neutralising the pH.

DOSINGDEVICES DEWATERINGSYSTEMS DUSTCONTROL

GREEN TECHNOLOGIES

LTD

Concrete wash water is caustic and usually has a high pH value ranging between 11 and 13 on a scale that runs from 1 (very acidic) to 14 (highly alkaline), making it extremely corrosive. It contains dissolved solids including sulphates and hydroxides from cement, oil and grease from equipment used on site. It takes 1,000,000L of water to dilute 1L of concrete wash.

Erosion and Sediment Control Plan

Appendix D: Record of CLG and Auckland Council Comments CLG Comments No comments were received during the CLG that occurred on 19 November 2019.

Auckland Council Comments Comment was received from Auckland Council on 30 January 2020: Page no. n/a

ESCP section n/a

Paragraph/ sentence

Comment

Resolution

The ESCP shows that sediment laden runoff will predominantly be controlled by directed flow into collection sumps and then pumped into settlement tanks and water treatment areas until an appropriate quality is met.

Further details on the water treatment system and as built of the final system will be provided prior to operation, and will be in accordance with the ESCP and resource consent conditions.

I note that the ESCP refers to indicative settlement tank volumes, and that this will be determined by several listed factors. I anticipate that details of the water treatment system will be provided to be in accordance with the ESCP and consent requirements prior to operation, as well as appropriate as built provided of the final system.

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No change to ESCP.