Notice of Requirement, Resource Consent Applicationand Assessment of Environmental Effects

10

Appendix J. Erosion and Sediment Control Plan

Earthworks Assessment ReportMatakana Link Road

Auckland Transport

Project number: 60586377

October 05, 2018

Earthworks Assessment Report Auckland Transport

Project number: 60586377

Prepared for: Auckland Transport AECOM

Quality informationPrepared by Checked by Verified by Approved by

Kristina HealyPrincipal EnvironmentalScientist

Duane Rollo Bruce Withnall Sam Stringfield

Revision HistoryRevision Revision date Details Name Position

1 28/09/2018 Final Sam Stringfield Project Manager

2 05/10/2018 Final (AT review commentsincorporated)

Sam Stringfield Project Manager

Distribution List# Hard Copies PDF Required Association / Company Name

Earthworks Assessment Report Auckland Transport

Project number: 60586377

Prepared for: Auckland Transport AECOM

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Earthworks Assessment Report Auckland Transport

Project number: 60586377

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Table of Contents

1. Introduction ............................................................................................................................................ 61.1 Overview ..................................................................................................................................... 61.2 Purpose of this report .................................................................................................................. 6

2. Project Summary ................................................................................................................................... 62.1 Need for the Project..................................................................................................................... 62.2 Project Location .......................................................................................................................... 62.2.1 Drainage and receiving Environments .......................................................................................... 72.2.2 Topography and Geology ............................................................................................................. 82.2.3 Groundwater ............................................................................................................................... 8

3. Construction Sequence and Methodology ............................................................................................... 93.1 Construction Yard Methodology ................................................................................................. 103.2 Bulk Earthworks Methodology .................................................................................................... 103.3 Bridge Methodology................................................................................................................... 103.4 Landslide Remediation .............................................................................................................. 11

4. Statutory Review .................................................................................................................................. 114.1 Auckland Unitary Plan (Operative in Part) .................................................................................. 11

5. General Erosion and Sediment Control Approach .................................................................................. 125.1 Key Principles ........................................................................................................................... 125.2 ESC Measures Design Philosophy ............................................................................................. 125.3 General Erosion and Sediment Control Measures ...................................................................... 135.4 Asphalt Works and Concrete Pumping / Pouring......................................................................... 14

6. Specific ESC Methodologies................................................................................................................. 146.1 Construction Yard ...................................................................................................................... 146.1.1 Stockpiling ................................................................................................................................ 156.2 Bulk Earthworks and Stabilisation\ ............................................................................................. 156.3 Bridge ....................................................................................................................................... 166.4 Wetland Construction ................................................................................................................ 166.5 Culvert Installation (Watercourses Crossings)............................................................................. 166.6 Remediation of Landslide .......................................................................................................... 176.7 Accidental Discovery ................................................................................................................. 176.8 Kauri Dieback Controls .............................................................................................................. 17

7. Approach in regard to Manu Whenua .................................................................................................... 188. Universal Soil Loss Equation ................................................................................................................ 189. Monitoring During Construction............................................................................................................. 1910. Heavy Rainfall Response and Contingency Measures ........................................................................... 1911. Site Reinstatement ............................................................................................................................... 2012. Final ESCP and CESCPs ..................................................................................................................... 20

12.1 Changes to the ESCP and CESCPs........................................................................................... 2013. Conclusions and Recommendations ..................................................................................................... 2114. References .......................................................................................................................................... 21Appendix A ESC Drawings .............................................................................................................................. 22Appendix B TP108 and SRP Calculations ........................................................................................................ 23Appendix C Accidental Discovery Protocols ..................................................................................................... 24Appendix D Kauri Dieback Operating Procedure for Matakana Link Road Project ............................................. 25

Earthworks Assessment Report Auckland Transport

Project number: 60586377

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Figures

Figure 1: Aerial view of the Project area showing current land uses, yellow line shows road corridor location(Source: Auckland Council GEOMAPS). ............................................................................................................ 7Figure 2: Project area catchment plan showing overland flow paths (OFP), rivers, 100 year floodplains andexisting stormwater infrastructure. Yellow line shows road corridor location and letters indicate the watercoursesreference name crossed by the Project route (Source: Auckland Council GEOMAPS). ........................................ 8

Tables

Table 1. General ESCMs ................................................................................................................................ 13Table 2. Sediment retention devices ............................................................................................................... 13Table 3. Construction yard and Matakana Road roundabout SRP design summary .......................................... 15Table 4. Bulk earthworks SRP design summary .............................................................................................. 15Table 5. Peak flowrates for watercourses where culverts are proposed ............................................................ 17Table 6. Summary cut and fill USLE calculation ............................................................................................... 19

Earthworks Assessment Report Auckland Transport

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1. Introduction

1.1 OverviewAECOM New Zealand Limited (AECOM) has been engaged by Auckland Transport (AT) to provide technicalassistance in erosion and sediment control design and earthworks assessment of effects related to constructionactivity for the Tūhonohono ki Tai (Matakana link road) project (the Project). This Earthworks Assessment reportis to be appended to the supporting Assessment of Environmental Effects (AEE) for the Project.

Note the report does not include the assessment for stream crossings and / or works within a watercourse asthese details are provided in the Bioresearches report Assessment of Ecological Effects: Tūhonohono ki Tai/Matakana Link Project (September, 2018) and the Notice of Requirement, Resource Consent Application andAssessment of Environmental Effects (September, 2018).

1.2 Purpose of this reportThis report provides an assessment of the effects related to earthworks activities and the required controls andmitigation measures to ensure earthworks do not result in erosion and release of sediment to watercourseslocated within the Project area. This report addresses Erosion and Sediment Control (ESC) measures for Stage 1and 2 of the Project.

This document has been prepared in accordance with the Auckland Council’s TP90 Erosion and SedimentControl Guidelines for Land Disturbing Activities in the Auckland Region (TP90) and the Erosion and SedimentControl Guide for Land Disturbing Activities in the Auckland Region – Guideline Document 2016/005 (GD05).Where there are inconsistencies between TP90 and GD05 the more conservative requirements have beenapplied.

The ESC plan contained in this report provides the framework for the construction of ESC measures andprovides site specific detail. The ESC report describes the methods and practices to be implemented to ensurethe effects of erosion and sediment generation are minimised and managed.

2. Project Summary

2.1 Need for the ProjectThe Project seeks to designate a road corridor and obtain the necessary regional resource consents, to enablethe construction, operation and maintenance of the new road. The designation corridor runs for a length of 1.35km between State Highway 1 (SH1) and Matakana Road, Warkworth. The Project has been designed andlocated to provide an alternative route between north Warkworth and the east coast settlements and beaches,with SH1 and the Puhoi to Warkworth (P2Wk) section of Ara Tūhono – Pūhoi to Wellsford Project which iscurrently under construction.

The Project will improve the function of the local network, helping to reduce travel times to/from Matakana andthe eastern settlements and beaches while assisting with the reduction of congestion at the Hill Street/SH1intersection. The Project will also provide access to future urban and light industrial zoned land located towardsthe north of Warkworth, thereby supporting the growth projected under the Auckland Plan 2050 and Future UrbanLand Supply Strategy (FULSS).

The construction of stage 1 of the Project is planned to commence in late 2019 and will take approximately 16-18months to complete. Stage 1 will involve bulk earthworks for the formation of the entire road corridor, paving oftwo lanes and shared path, bridge construction and stormwater infrastructure. Stage 2 is programmed to beimplemented between 2036 and 2046, when the traffic demand exceeds capacity and will two additional lanes,shared paths and widened bridge.

2.2 Project LocationAs shown on Figure 1, the Project area is located within the urban fringe of Warkworth, with land uses intransition from pastoral farming to industrial and other urban activities. It is recognised that the area is largely

Earthworks Assessment Report Auckland Transport

Project number: 60586377

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zoned Future Urban under the Auckland Unitary Plan (Operative in Part) (AUP(OP) and will be rezoned fordefined urban land uses following an upcoming structure plan process led by Auckland Council (AC). Given thecurrent predominantly pastoral farm land uses in the Project area, there is little in the way of existing stormwaterinfrastructure and this is also reflected by the lack of a current Catchment Management Plan. It is also noted thatthe Project area is not subject to any Stream Management Flow controls under the AUP (OP).

Figure 1: Aerial view of the Project area showing current land uses, yellow line shows road corridorlocation (Source: Auckland Council GEOMAPS).

2.2.1 Drainage and receiving EnvironmentsThe Project area is crossed by six watercourses, two of which are permanent (Watercourses E and F) and two ofthese watercourses are fed by headwaters within the corridor (Watercourses B and C). The most significant ofthese watercourses (Watercourse F) is located within a heavily forested gully, which flows directly to theMahurangi River.

A detailed assessment of the ecological values and assessment of effects on these watercourses and theirlocations is provided in the Bioresearches report Assessment of Ecological Effects: Tūhonohono ki Tai/ MatakanaLink Project (September, 2018).

As shown by Figure 2, the Project area and surrounding properties feature a number of floodplains (for 100 yearARI events) and “flood prone” areas (areas where ponding could occur during 100 year ARI rainfall events).These flooding overlays are present along Watercourse A, through the Warkworth Showgrounds and alongWatercourse F. Additional flooding risks affect SH1 (both by the Project area and in urban Warkworth) andproperties to the south-west.

Matakana link road

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Figure 2: Project area catchment plan showing overland flow paths (OFP), rivers, 100 year floodplains and existing stormwater infrastructure. Yellow line shows road corridor location and letters indicate the watercourses reference name crossed by the Project route (Source: Auckland Council GEOMAPS).

2.2.2 Topography and GeologyThe Project area is located on undulating rural land, with a level difference of 33m between the two terminuses of the corridor. The underlying geological conditions of the Project area have been assessed by Jacobs Limited and reported in the memo Groundwater and Geotechnical Assessment of Effects (Jacobs, 2018). The geotechnical and groundwater report associated with the AEE has identified the following conditions (chainage runs from east to west, i.e. Matakana Road to SH1):

· Ch 0 – 120: Near surface limestone (Mahurangi Limestone);

· Ch 120 – 620: Alluvial deposits over inferred Pakiri Formation;

· Ch 620 – 1080: Northland Allochthon soil with some pockets of alluvium and colluvium; and

· Ch 1080+: Alluvium of an unconfirmed depth.

The geotechnical report highlights the presence of a shallow debris flow through the centre of the alignment, resulting in significant volumes of earthworks to ensure a stable road structure, as well as impacting on the position of other Project related infrastructure within the alignment (i.e. sediment retention ponds or wetlands).

2.2.3 GroundwaterThe proposed cuts for the embankments (Cut 1 and Cut 2) are expected to lower groundwater levels within the immediate vicinity of the cuts (Jacobs, 2018b). Due to the lack of existing groundwater users or groundwater dependent ecosystems within and adjacent to the Project area the effects of the drawdown were assessed as being minor with no requirement for monitoring or specific construction mitigation.

B

C

A

F

E

D

Matakana link road

G

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3. Construction Sequence and MethodologyThe physical works associated with the Project will be undertaken in two stages. There are three maincomponents of the Project: the road carriageway including two cut faces (bulk earthworks), Watercourse F singlespan bridge and the roundabout intersection with Matakana Road. The Constructability Assessment Report(Wright, 2018) provided a likely methodology for constructing the new infrastructure and provides a basis for theAEE. The scope of physical works associated with the Project and stormwater management is based on theproposed methodology as set out in that report.

Stage 1 construction is proposed to commence in late 2019 and will include:

· Bulk earthworks (for both Stages 1 and 2), including a shear key, creating a 29.6m wide corridor with a14.45m wide verge;

· The formation of a paved road with two 3.2m wide traffic lanes;

· 2.7m wide berm containing street trees and street lighting;

· 3.5m wide shared path for pedestrians and cyclists;

· 1.7m wide berm adjacent the Project’s southern boundary;

· A bridge and associated abutments (including the abutments required for the Stage 2 crossing);

· Roundabout at Matakana Road;

· Reclamation of a stream (Watercourse B);

· Four culverts (Watercourses C, D and E, with an additional culvert for an overland flow path);

· Three stormwater treatment wetlands with associated outfalls; and

· Landscaping for urban design improvement s.

The programme of physical works for Stage 1 is estimated to take approximately 16 – 18 months withsequencing as follows:

1. Relocation of utility services prior to the construction of the site accesses and egresses on Matakana Roadand SH1;

2. Site establishment;

3. Installation of erosion and sediment controls;

4. Installation of culverts to allow construction access along the site;

5. Construction of earthworks in the 2019/2020 summer season;

6. Construction of the bridge in 2020;

7. Construction of the shared path and landscaping;

8. Construction of pavement and surfacing (two lanes only) in 2020;

9. Construction of traffic services; and

10. Disestablishment from the site.

Stage 2 is currently programmed to be undertaken between 2036 and 2046, once the Stage 1 two-lane roadcorridor reaches capacity. Proposed Stage 2 works include:

· Minor earthworks (mostly consisting of the stripping of top soil and minor excavations for drainage);

· The formation of two additional 3.2m wide traffic lanes ;

· 2.7m wide roadside berms, planting of street trees and street lighting;

· Two 2.2m wide cycle paths;

· Two 2m wide footpaths;

· Two 1m wide berms running along the southern and northern boundaries of the corridor;

· Services , including connections to the Stage 1 stormwater wetlands;

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· An additional 13m wide, two-lane road bridge and shared path across the Mahurangi Tributary. This willeither be a separate structure to the Stage 1 structure with a 3m separation distance between the twostructures or it will be stitched to the existing structure; and

· The construction of finalised street furniture.

The proposed methodologies for specific sections of the Project are defined in the following sections.

3.1 Construction Yard MethodologyThe indicative location for the construction yard is at the intersection with Matakana Road as it provides arelatively flat area that is close to the area where the bridge will be constructed. The final location of thesefacilities will be confirmed after contract award.

The construction yard will include site offices, toilets, equipment and materials storage and hazardous substancestorage. Physical works to prepare the construction yard location will likely include site levelling and stabilisationusing aggregate, as well as the laying of hard stand sealed surfaces.

3.2 Bulk Earthworks MethodologyThe Construction Assessment Report proposes to construct the haul road within the footprint of the roadcarriageway rather than beside the road. It would progress by constructing and using the SIL immediately behindthe advancing earthworks excavations and ahead of the truck loading locations. This would allow trucks to movefreely and quickly on the competent layer to and from the road access points without the risk of bogging down.The culverts will be laid as the haul road and earthworks progress (Use of the SIL within the road carriageway asthe haul road is preferable due to the available land, impact of the cut/ fill batters on available width, and steeptopography.

The imported SIL material is expected to be slightly weathered brown rock commonly found in quarriesimmediately above the lower, more competent premium rock used for pavement construction. This brown rock,also known as “run of pit”, is commonly used for this purpose as an engineered foundation layer. It provides ahigh natural California Bearing Ratio (CBR) value and does not require stabilising.

3.3 Bridge MethodologyTo construct the single span bridge it is proposed to provide a temporary construction staging bridge nominally40m long and 10m wide, across the valley of Watercourse F shown in Appendix A. The temporary staging bridgewill also be used as the haul route between Matakana Road and the works site.

Figure 3 Temporary staging bridge (Source: Wright, 2018)

This staging would be constructed progressively, span by span, across Watercourse F and the riparianvegetation. There will be some loss of riparian vegetation for the temporary staging bridge. The vegetation losswill cause minor indirect adverse effects on the environment (Bioresearches, 2018). The staging will occur asfollows:

i. Install 750mm-900mm diameter temporary pile casings to a set ahead of piling rig on a 7.5mm x 10m grid.The piling rig should be established on natural ground at the start of the staging;

ii. Construct cross heads and beams to the first span;

iii. Fix timber decking to the first span;

iv. Move piling rig onto the completed first span and repeat the process for successive spans; and

v. Extract the casings on completion.

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The piles of the temporary staging bridge will be positioned to avoid the channel of Watercourse F, negating theneed for works within the watercourse associated with the bridge construction.

3.4 Landslide RemediationThe Groundwater and Geotechnical Assessment (Jacobs, 2018b) recommends the remediation of an existingshallow creep type landslide at Chainage 730 to prevent long term movement and damage to the roadembankment. The detailed design of the proposed remediation has not been completed however Jacobsrecommended construction of a shear key to remedy the landslide in their Geotechnical Interpretative Report(Jacobs, 2018c). Other potential methods include shear piles and to completely dig out and remove the soil downto the underlying Northland Allochthon rock. As the method of remediation has yet to be determined there is noproposed construction method. Therefore specific erosion and sediment control measures related to the landslidehave not been defined in this report. Section 6.6 provides some ESC measures to be considered in thecontractor’s updated ESC Plan.

4. Statutory ReviewThe AEE prepared to support the statutory applications for the Project works provides a review of the necessarystatutory plans applicable to the earthworks component of the project. This section summarises the applicablesections of the AUP (OP) as they relate to earth disturbance.

Within Stage 1 a total of approximately 78,576m3 will be cut to fill, 108,134m3 cut to waste and 9,060m3 ofimported fill will be used over an area of approximately 12.1ha (121,000m2). The earthworks associated with theworks will not all occur at the same time and areas will be progressively stabilised throughout the course ofworks. The slope of the Project area is mostly between 5 to 10 degrees however around the watercourses theslope increases significantly and ranges from 10 to 20 degrees.

4.1 Auckland Unitary Plan (Operative in Part)The Project area extends over land zoned as Light Industrial (western extent) and Future Urban zone in the AUP(OP). Preliminary structure planning for land use shows the eastern extent of the Project route as having anunderlying residential zone.

The Sediment Control Protection Areas (SCPA) (regional) are defined as:

a. 100m either side of a foredune or 100m landward of the coastal marine area (whatever is the morelandward of mean high water springs); or

b. 50m landward of the edge of a watercourse, or wetland of 1000m² or more.

As previously discussed a number of watercourses are crossed by the Project route. These crossings and effectson the watercourses are assessed in the Bioresearches ecology (September, 2018). The Project corridortraverses six SCPAs.

Table E26.5.3.2 specifies the activity status of land use and development activities pursuant to section 9(2) of theResource Management Act 1991 (Reginal). Restricted discretionary activity status is applicable to earthworksgreater than 2,500m2 where land has a slope greater than 10 degrees (A106) and or within SCPAs (A107). Thetotal area of earthworks is estimated at 121,000m2.

The restricted discretionary activity assessment criteria are provided in E26.5.7.2. The criteria include compliancewith applicable standards (e.g. TP90) and mitigation of significant adverse impacts. This report provides themethodology for implementing best practise erosion and sediment control measures and ensuring that there areno significant adverse effects on receiving environments.

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5. General Erosion and Sediment Control Approach

5.1 Key PrinciplesKey principles of sediment and erosion control have been identified as the following:

1. Staged construction to limit the time and area that soil is exposed and prone to erosion;

2. Protect steep slopes by using diversion bunds, contour drains, or maintaining existing vegetation;

3. Stabilise exposed areas rapidly with vegetation, mulch, grassing or geotextile materials;

4. Install perimeter controls above the site to keep clean runoff out of the worked area;

5. Use of sediment retention ponds with chemical flocculation to treat sediment laden runoff; and

6. Assess and adapt the approach to erosion and sediment controls throughout the life of the Project.

5.2 ESC Measures Design PhilosophyThe ESC measures (ESCMs) detailed in this report and drawings (60586377-SHT-EW-1001 to 1003) have beendesigned based on the likely construction methodology presented in Section 3.0. The final constructionmethodology will be confirmed after detailed design and on appointment of the physical works contractor. Actualsite conditions may also vary from the information available at the time this technical report was prepared.Therefore, a general “tool box” of ESCMs are presented based on the following construction elements for Stage 1and 2 of the Project:

· Site establishment and construction yard set up;

· Construction of erosion and sediment control devices;

· Bulk earthworks for road carriageway formation, Matakana Road roundabout, and stormwater drainageinfrastructure;

· Stabilisation;

· Bridge and abutment construction including temporary staging platform;

· Stage 2 road surfacing, and shared pedestrian and cycle path; and

· Deconstruction of sediment retention ponds (SRP) and construction of stormwater treatment wetlands(where locations overlap).

The Contractor will review and apply the proposed ESCMs as appropriate. The ESCM design will be confirmedby the Contractor in their ESCP.

The following documents were referenced in preparation of the ESC assessment report:

· Auckland Council, Erosion and sediment control guidelines for land disturbing activities in the AucklandRegion Technical Publication No. 90;

· Auckland Council, Erosion and Sediment Control, Guidelines for Land Disturbing Activities in the AucklandRegion, Guideline Document 005; and

· Auckland Council, Guidelines for stormwater runoff modelling in the Auckland Region, Technical Publicationno. 108.

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5.3 General Erosion and Sediment Control MeasuresThe general erosion control measures to be used within the Project area during construction are presented inTable 1 and sediment retention measures are presented in Table 2.

Table 1. General ESCMs

Measure/ Device Description

Construction staging and sequencing · Site staging reduces erosion from a site by reducing the amount of soilexposed at any one time.

· Limiting site disturbance preserves areas that are highly susceptible to erosionand maintains them as vegetated areas.

· Construction sequencing involves planning land disturbance activities tocoincide with the installation of management practices.

Runoff diversions – clean and dirty · Clean water diversions (CWD) to divert up-gradient clean runoff arounddisturbed areas to limit the erosion potential and volume of water for treatment(this includes OFP running through the site).

· Dirty water diversions (DWD) to divert sediment laden runoff within disturbedareas to retention and treatment devices.

· CWD and DWD to be designed to 20 year ARI storm event with 300mmfreeboard.

· CWD and DWD to be stabilised using grass or geotextile material to preventscour.

Contour drains · Temporary excavated channels or ridges or a combination of both,constructed slightly off the slope contour to break overland flow draining downdisturbed slopes.

· Reduces slope length and thus the erosive power of runoff, and divertssediment laden water to appropriate controls via stable outlets.

· Can be used as mid-slope contour banks and/or drains for the short-term,temporary structures placed across unprotected slopes within the workingarea at the end of each day’s work, before site closedown or when rain isimminent.

Lime conditioning · Lime may be used during bulk earthworks if the material is overly wet toprovide a more stable material to work with.

· Lime would be applied to reduce soil moisture, plasticity or improve long termstrength (e.g. on haul road).

Location of ESC devices · To be located outside the 100 year ARI floodplain, and away from (OFP) andstreams.

Rock check dams · Small dams made of rock or other non-erodible material constructed across aswale or channel to act as a control structure. Can be used in CWD and DWDas a temporary measure.

· Reduces the velocity of flow within the channel and prevent scour of thechannel surface. Check dams also allow for some settlement of suspendedsolids within the channel.

Stabilisation for erosion and dustmanagement purposes

· Usually temporary and type of stabilisation dependent on length of time areanot worked, site slope, accessibility, and proximity to watercourses.

· Includes top-soiling and grass seeding, hydroseeding, mulching, turfing anduse of geotextiles, plastic, erosion control blankets and geo binders.

· Use of biodegradable matting for planting and stabilising cut faces.

Stabilised entrance ways · Stabilised pad of aggregate on a woven geotextile base located at any entryor exit point of a construction site.

· Prevents site access points becoming sources of sediment and assists inminimising dust generation and disturbance of areas adjacent to the roadfrontage.

· Depending on location and earthworks being undertaken, a formal wheelwash system will be required to ensure sediment is not transported onto thepublic road network.

Table 2. Sediment retention devices

Measure/ Device Description

Sediment retention ponds (SRP) · Primary sediment control measure which produces the most effectivetreatment of sediment laden runoff if designed and constructed according toTP90/ GD05.

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Measure/ Device Description

Decanting earth bunds (DEB) anddecant systems (based on volume of2% of the contributing catchment)

· Temporary berms or ridges of compacted soil, which are constructed to createimpoundment areas where ponding of sediment-laden runoff can occur.

· Discharge outlets to watercourses to be stabilised to prevent erosion. Levelspreaders to be used where appropriate.

Chemical treatment · Use of a flocculation agent to increase the treatment efficiency of SRPs andDEBs.

· Best practice is to undertake site specific bench testing to determineapplication rates for soil types and installation of rain activated systems.Manual batch dosing can be used to achieve discharge clarity.

Container impoundment systems · Area around bridge abutments is too steep and confined for SRP or DEB so asump with pump to SRP or DEB or a container impoundment system will berequired.

Super silt fences and silt fences · Super silt fence to be used where the sensitivity of the receiving environmentis high.

· Secondary control devices to be used as the last line of defence around awork area or to provide an additional level of protection to a watercourse.

5.4 Asphalt Works and Concrete Pumping / PouringThe environmental risk of concrete or asphalt works is high and it is recommended that drainage channels arecompletely isolated. If this is not practicable, then careful placement of sandbags or bunds should beimplemented.

Other recommended controls include:

· Delay asphalt/concreting works when bad weather is forecasted;

· Minimise the volume of water used on site (e.g. in dust suppression, concrete cutting) so there is less tocontrol;

· Dust is created during dry concrete or asphalt cutting. Use saws that can have a vacuum attached tominimise the amount of dust produced, or use a wet vacuum, to collect all concrete or asphalt contaminatedmaterials;

· If the above is not practical, divert all runoff to the construction pit/ trench or unsealed ground, away fromsurface water and OFP. Runoff or wash water contaminated with concrete fines / dust is highly alkaline andcannot be diluted, therefore, all captured runoff from concrete cutting and/or cement mixing must be treatedto bring pH back to neutral (pH 7);

· Wash all equipment and tools in a designated wash area or on a large grassed area well away fromstormwater swales, streams and creeks;

· Do not allow concrete trucks or concrete pumpers to wash out on site unless there is a designated washarea with capture and treatment systems in place; and

· Use tarpaulin sheets under concrete pumps and delivery chutes to capture any spills.

The majority of concrete will be prepared off site and brought to site when required. There will not be a concretebatch plant within the Project works area.

6. Specific ESC Methodologies

6.1 Construction YardA relatively flat gravel and hard stand yard of approximately 1700m2 will be constructed with a stabilised entranceand wheel wash at the entrance. ESC drawing reference number 60586377-SHT-EW-1001 depicts ESCmeasures for the indicative Matakana Road site.

Silt fences will be installed around the down gradient perimeter of the yard to retain the dirty water generated byland disturbing activities and the movement of construction vehicles and materials. All sediment laden flow fromthe construction yard will be diverted to an SRP (refer to Table 3 for design details) by DWD and upon treatment

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be discharged to the downgradient stream (tributary of Watercourse F). Erosion and scour protection in the formof geotextile and rip rap will be used at the outlet to protect the watercourse.

CWD will be installed around the up gradient perimeter of the construction yard to prevent clean water fromentering the site, which will be diverted to the adjacent stream. If sheet flow cannot be achieved prior to dischargeto the watercourse, erosion and scour protection at the outlet of the CWD will be constructed.

Table 3. Construction yard and Matakana Road roundabout SRP design summary

Device Catchment Area

Catchment slopes>18%

Min pondstoragevolumes

Pondbasedimensions

Pondshaperatio

Primaryspillwaytype

Dischargelocation

Emergency spillway

Embankmentrequirements

SRP 1 20,850m2 NO 665m3 10.5m x31.5m

3H:1V 150 Øpipedspillwayonto ripraparea

TributaryofWatercourse F

300mmfreeboard,300mmdepth toweir, 6mminimumwidth

Ensureemergencyspillwayspills ontovegetatedlandand/orriprap

6.1.1 StockpilingStockpiles, for the most part, of spoil and materials to be used in construction will be located along the alignmentwhere they need to be used or removed from. In addition, small temporary stockpiles may be located adjacent towork areas as required, within the Project area. All practicable steps will be taken to ensure that all stockpiledmaterial shall be located clear of any watercourses or floodplains.

Runoff diversion channels, earth bunds or silt fences will be constructed around stockpile areas to impoundsediment runoff. Temporary stabilisation measures will be used if stockpiles are to be in place over the wintermonths. During use, stockpiles will be wetted or covered to prevent dust generation.

The Project will not require a site concrete batch plant. Precast materials will be brought to site when requiredfrom existing concrete batch plant(s), likely to be procured in Auckland or from the Puhoi to Warkworth contractor.

6.2 Bulk Earthworks and Stabilisation\The road carriageway and cut/ fill embankments will require the bulk of the earthworks. The ESCMs are shownon drawings 60586377-SHT-EW-1001 to 1003. The generally poor quality of the in-situ soils is likely to requirethe transport of spoil off site for disposal at consented location(s).

The Construction Assessment Report (Wright, 2018) proposes to construct the haul road within the footprint ofthe road carriageway rather than beside the road, following the summarised methodology in Section 3.2 (Wright,2018).

Three SRPs will be constructed along the route as it progresses. DWD bunds/ channels will be used to divertrunoff from worked areas to the SRPs. CWD will be used up-gradient of work areas to divert clean runoff aroundthe work areas. Table 4 provides the design information of the two SRPs associated with the bulk earthworksfrom SH1 to Watercourse F (bridge location).

Table 4. Bulk earthworks SRP design summary

Device Catchment Area

Catchment slopes>18%

Min pondstoragevolumes

Pondbasedimensions

Pondshaperatio

Primaryspillwaytype

Dischargelocation

Emergency spillway

Embankmentrequirements

SRP 2 27,150m2 NO 832m3 12m x 36m 3H:1V 150 Øpipedspillwayonto ripraparea

Watercourse C

300mmfreeboard,300mmdepth toweir, 6mminimumwidth

Ensureemergencyspillwayspills ontovegetatedlandand/or

Earthworks Assessment Report Auckland Transport

Project number: 60586377

Prepared for: Auckland Transport AECOM16

Device Catchment Area

Catchment slopes>18%

Min pondstoragevolumes

Pondbasedimensions

Pondshaperatio

Primaryspillwaytype

Dischargelocation

Emergency spillway

Embankmentrequirements

riprap

SRP3 33,450m2 NO 1,084m3 14m x 42m 3H:1V 150 Øpipedspillwayonto ripraparea

Watercourse A

300mmfreeboard,300mmdepth toweir, 6mminimumwidth

Ensureemergencyspillwayspills ontovegetatedlandand/orriprap

Silt fencing will also be used up-gradient of a watercourse that is located down gradient of the area, therebyproviding another active level of protection. The SRPs will provide the primary control measure with silt fences,providing a secondary control around watercourses ensuring sediment laden runoff doesn’t enter waterways. Thesilt fencing will also provide a demarcation where machinery will not be allowed to enter. Silt fences will bedesigned in accordance with GD05 requirements including installation along site contours, and returns on longruns and at the ends.

6.3 BridgeThe methodology for the bridge construction is provided in Section 3.3 (as proposed in the ConstructabilityAssessment Report, Wright (2018)).

An access track from the main haul road will be required on both banks to meet up with the temporary stagingbridge. The detailed design of the bridge abutments is yet to be completed however the ESCMs presented arebased on the abutments consisting of retaining walls to support the approach embankments and single spanbridge deck.

Watercourse F is located within a steeply incised gully and so the floodplain is constrained, however it is possiblethat some ESCMs may need to be located within the 100-year floodplain. Any ESCMs within the floodplain are tobe constructed so that failure will not cause damage to the downstream environment or blockages within thewatercourse. Silt fences are recommended to be used between the works areas and the watercourse to capturerunoff. DEBs will be constructed with floc sock treatment as the primary retention measure with the silt fenceproviding secondary protection. Drawing 60586377-SHT-EW-1001 shows the ESCM for the bridge construction.

The access track will be stabilised with geotextile and aggregate suitable for the type of machinery (e.g. cranes)that will be accessing the staging bridge. Contour drains will be used across the access track to intercept flow asrequired.

6.4 Wetland ConstructionThe wetland locations overlap with SRP locations. Therefore, construction of the wetlands will be completed afterthe bulk earthworks have finished. Additional ESCMs will be installed specifically for the wetland construction.The sediment from the SRPs will need to be removed and may be used as fill if suitable, if not the material willhave to be removed from site as spoil. Silt fences will be used down gradient of the wetland construction areas.

6.5 Culvert Installation (Watercourses Crossings)The project alignment crosses six watercourses. These locations are shown in Drawing 60586377-SHT-DR-1001. Bioresearches has classified each watercourse crossing in their ecology assessment and found that two ofthese watercourses (Watercourses C, and D) are intermittent, meaning they are stream reaches that cease toflow for periods of the year. Watercourse B has been assessed as an ephemeral stream. For the purposes ofESC it has been assumed that works within a watercourse are likely to be required for the culverting ofwatercourses which traverse the alignment.

Works in or around watercourses have the potential to have a direct impact on watercourse habitat (e.g. byhabitat disturbance or destruction) and on water quality (such as through sediment and temperature relatedeffects). Stream diversions are required to establish dry, off-line work areas to allow the open-cut trenching to beundertaken while minimising the risk of erosion and sediment generation.

Earthworks Assessment Report Auckland Transport

Project number: 60586377

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These small crossings and construction should be scheduled for the driest part of the earthworks season(generally January to March) when flow rates will be at their lowest or not at all. Every effort must be made tocomplete work within a watercourse in the shortest time possible. Work sites within watercourses must not be leftexposed when the works area is unattended or for greater than 12 hours. Similarly weather forecasts must beclosely monitored so that crossings can be stabilised before rainfall. Stabilisation should involve covering allexposed areas within the work site with geotextile and removing any debris which could cause a blockage.

Given the likely low flowrates, diversion around the works area can be achieved using an upstream dam andpumping around the work area to discharge back into the channel downstream of the work area. Diversions ofthis nature are likely to be in place for a short period of time (approximately 3 weeks), therefore the dam andpump capacity will need to be designed to manage the 1 year flow and a stabilised overflow system designed tomanage the 20 year flow (in accordance with GD05). Calculated flowrates for each watercourse crossing areprovided in Table 5 (full calculations are in Appendix B). Within the off-line dry work area, diversion bunds and siltfences will be used as necessary for clean water diversion (up gradient of the site), and dirty water capture andtreatment (silt fence).

If culvert installation works are undertaken during the summer season, it is possible fish will not be encounteredin the work areas as flowrates will be low. However, before works start, the stream will be inspected by anecologist to identify and remove any fish prior to construction activities commencing.

Table 5. Peak flowrates for watercourses where culverts are proposed

Culvert Reference Watercourse Reference Total Catchment Area (m2) Peak Flowrate 20yr (m3/s)

1-1 E 49500 0.92

2-1 D 27800 0.52

2-2 C 20850 0.39

3-1 B 12400 0.23

6.6 Remediation of LandslideAs described in Section 3.4 the method for remediating the landslide has not been confirmed. Depending onselected remedy the construction is likely to require dewatering. If dewatering is required a Dewatering Plan willbe required which will detail as a minimum:

· Specific dewatering procedures and methodology;

· Dosing rates and batch dosing methodology if flocculent treatment is required; and

· Monitoring, and contingency measures (including a record sheet).

Depending on the scale of earthworks silt fences and or DEB should be used to retain sediment laden flowsassociated the landslide remediation works. CWD will be required upgradient of the works areas to divert cleanwater around the earthworks.

6.7 Accidental DiscoveryChapter E11.6.1 Accidental discovery rule in the AUP (OP) provides the procedures to follow in the event ofdiscovery of sensitive material during earthworks and construction activities. All workers are to be briefed duringsite induction and toolbox meetings of the procedure and reporting requirements.

The procedure includes the requirement to stop work within 20m of the discovery, notify authorities (includingMana Whenua and NZ police where applicable), and conditions relating to the recommencement of works.Details of site archaeology are provided in the Matakana Link Road, Warkworth: Archaeological Assessment(Dawson et al, 2018).

6.8 Kauri Dieback ControlsThe Ecology Assessment concluded that the forest around Watercourse F (the main Mahurangi River Tributary)was symptomatic for PTA (Phytophthora taxon Agathis) infection. As PTA is a soil-bourne pathogen, the

Earthworks Assessment Report Auckland Transport

Project number: 60586377

Prepared for: Auckland Transport AECOM18

movement of vehicles, equipment and spoil/ topsoil has the potential to spread the disease into the Project areawhich would be detrimental to the surrounding kauri forest (Bioresearches, 2018).

The Ecology Assessment Report, Appendix V included a summarised version of the Kauri Dieback StandardOperating Procedures written specifically for the Project (Bioresearches, 2018). This procedure has been copiedin its entirety and is provided in Appendix D.

7. Approach in regard to Manu WhenuaNgāti Manuhiri and Te Kawerau a Maki represented by the Te Kawerau Iwi Tribal Authority (TKITA) havesubmitted Maori Values Assessments (MVA) and have been involved in the multi criteria assessment process forthe route selection. Their respective reports provide insight to the specific values associated with the Project areaand in particular the mauri of water.

In relation to the earthworks, Ngāti Manuhiri are advocating for:

· Retention of excavated soils on site as a preference rather than removal, with the exception ofcontaminated soils which should either be remediated on site or safely and appropriately disposed of;

· Retention of natural OFPs wherever possible;

· Use of robust and environmentally sustainable sediment control mechanisms;

· Highest standards of erosion and sediment controls during construction (not just ‘meeting’ Councilguidelines);

· Measures to minimise heavy earth-working equipment discharges of excessive contaminants to air duringconstruction works;

· Dust suppression measures as appropriate;

· Avoidance of native vegetation removal for any works;

· Use of Accidental Discovery Protocols which take effect if cultural material (e.g. koiwi or bone) is uncoveredthrough earthworks, ground disturbance or natural erosion;

· Contractors and AT Project Managers to attend a cultural induction with Ngāti Manuhiri;

· Assurance that all heavy machinery used on site either have not recently worked in areas known to havekauri dieback disease or that thorough cleaning has been undertaken; and

· New infrastructure can contribute to good cultural and environmental outcomes through the use ofsustainable, energy efficient materials and construction methods. Earthen, recycled or other sustainablysourced materials (e.g. organic flocculants, solar power) and careful design can enhance overall value.

TKITA recommended that AT provide for the following as they relate to stormwater management in the Projectplanning, design and construction phases:

· That cultural monitoring will be required for all invasive works within the project footprint including duringarchaeological investigations and future earthworks; and

· That if intact subsurface archaeological features or artefacts associated with Maori are exposed during anyearthworks, it will be necessary to cease earthworks in the vicinity and representatives of TKITA andHeritage NZ should be notified immediately of the discovery (as stipulated in the Accidental DiscoveryProtocol).

Consideration has been given to the concerns and recommendations raised by Mana Whenua in the MVA’swhere practicable. AT will continue to work with iwi as project partners to discuss options to address therecommendations within the MVA’s.

8. Universal Soil Loss EquationThe Universal Soil Loss Equation (USLE) is often used to assess the amount of soil that may be lost fromearthworks. It is recognised that this means of estimating the soil loss differs significantly from the actual losses.

Earthworks Assessment Report Auckland Transport

Project number: 60586377

Prepared for: Auckland Transport AECOM19

The formula and parameters are often used to compare the potential scale of the impact that earthworks mighthave on receiving environments.

The following areas are of particular interest:

· At risk (i.e. steeper) sites can be identified as these can discharge significantly more sediment;

· Larger earthworks projects, with longer durations of exposure are likely to discharge more sediment; and

· Smaller projects, with poor erosion and sediment control measures could also discharge large amounts ofsediment relative to size.

Table 6 summarises the USLE outputs for each of the sub-catchments within the Project area.

Table 6. Summary cut and fill USLE calculation

ESC DeviceCatchment

Catchment Size (ha) Work Duration(months)

Unmitigated Soil Loss(tons)

Mitigated Soil Loss(tons)

SRP1 2.085 4 78.5 13.7

SRP2 2.715 3 73.5 12.9

SRP3 3.35 3 78.7 13.8

DEB1 0.35 1.5 9.9 3.5

TOTAL 8.5 240.6 43.9

Refer to Appendix B for the detailed calculations. The mitigated soil loss is based on a sediment control efficiencyof 75% for the SRPs and 50% for the DEB. This efficiency increases to 90% and 65% respectively whenchemical treatment is used to improve the treatment efficiency of the sediment retention devices.

9. Monitoring During ConstructionThe Contractor will identify the person on site responsible for erosion and sediment control (most likely the SiteSupervisor or Environmental Advisor). The Contractor will keep daily records of site inspections and any erosionor sediment issues that may arise. The records will be included with other site information required under theContract and will be available for inspection by the Engineer to the Contract during normal working hours. Theserecords will be retained for the duration of the Contract.

Should excessive sediment be found in the downstream system directly attributed to failures of sedimentmanagement at a works site, then the Contractor may be required to cover the cost of cleaning or remediation.

All silt fences, bunds, SRPs and specific measures constructed for the purpose of erosion and sediment controlwill be inspected on a weekly basis and after rainfall events. Inspections will include, but will not be limited to, thefollowing:

· Scouring and adequacy of scour protection;

· Areas of damage;

· Damage caused by adjacent earthworks; and

Visual inspection of sediment pond/pit discharge water for clarity and presence of sediment.

10. Heavy Rainfall Response and Contingency MeasuresThe construction works are scheduled to begin late 2019 and the programme of work is likely to extend over 16-18 months. The programme will be finalised once a Contractor has been appointed. High intensity rainfall eventscan occur during the summer months as well as prolonged rain events during the winter months. The Contractoris responsible for monitoring weather forecasts, inspecting all erosion and sediment control measures andundertaking any remedial works required prior to the forecasted rain event.

In general, the Contractor will:

Earthworks Assessment Report Auckland Transport

Project number: 60586377

Prepared for: Auckland Transport AECOM20

· Review weather forecasts daily to anticipate periods of risk and be prepared to undertake remedial workson erosion and sediment control measures to suit the climatic conditions;

· Monitor the effectiveness of such measures after storms and incorporate improvements where possible inaccordance with best management practice;

· Ensure appropriate resources are available to deal with the installation of additional controls as and whenneeded; and

· Inform AC if there are any concerns associated with the measures in place.

11. Site ReinstatementRemoval of control measures is only to occur once permanent surfaces, grass and vegetation have beenestablished. Due care will be taken during the removal process so as not to mobilise any sediment. Any trappedsediment will be moved off site to landfill.

Once all controls are removed all parties are to sign off that the works are complete and have been completedsatisfactorily.

12. Final ESCP and CESCPsThe erosion and sediment control measures detailed in this ESCP are based on the Project description andconstruction methodology described in Section 2.0 and 3.0. As the detailed design is not complete and thecontractor(s) has yet to be appointed the construction methodology is likely to change. Therefore prior to workcommencing on specific sections of the Project, site specific Construction Erosion and Sediment Control Plans(CESCPs) must be developed by the contractor.

The CESCPs must include as a minimum the following information:

· ESC drawing(s) showing locations of ESCMs, site contours, flow directions and runoff calculations (ifappropriate);

· Detailed designs of specific ESCMs as required e.g. diversion bunds, decanting earth bund;

· Any requirement for chemical treatment including design and details of dosing rates etc.;

· Specific contingency measures (particularly for works near watercourse); and

· Roles and responsibility of Contractor, AT and AC, including names and contact details (this may be specificto the type of construction or as specified in the Construction Environmental Management Plan).

12.1 Changes to the ESCP and CESCPsDuring construction, the installed erosion and sediment control measures will be reviewed as constructionprogresses. The review will address any changes of design assumptions, catchments and constructionmethodology. If ground conditions, stabilisation works, or catchments are different to those adopted in thedetailed design of the control measures then the system will be amended accordingly in order to comply.

Changes to the ESCP and or CESCPs can be made after consultation with the following parties:

· Supervising Engineer;

· AT; and

· AC.

AC is to be notified in writing of any significant changes. Certification must be sought from AC prior to worksassociated with the amendments being undertaken; 5 working days shall be given to AC for this certification.

Earthworks Assessment Report Auckland Transport

Project number: 60586377

Prepared for: Auckland Transport AECOM21

13. Conclusions and RecommendationsAll construction activities associated with construction of the Project have potential to cause erosion and generatesediment. Based on the preliminary designs and likely construction methodology, a suite of erosion and sedimentcontrol measures have been identified to avoid or mitigate potential effects on the receiving environments.Specific activities have been identified to describe in more detail the layout of required ESCMs. Once detaileddesigns are complete and the Contractor has confirmed the construction methodologies CESCP(s) should bedeveloped to detail implementation of the ESCMs identified in this ESCP. With correct design and construction ofESCMs it is anticipated that the effects on the receiving environments will be temporary and no more than minor.

14. ReferencesBeca Carter Holdings & Ferner Ltd (1999). Guidelines for stormwater runoff modelling in the Auckland Region.Technical Publication No.108. Prepared for Auckland Regional Council

Bioresearches (2018). Assessment of Ecological Effects: Tūhonohono ki Tai/ Matakana Link Project. Report forAuckland Transport. Pp 71

Dawson, L., Phear, S., and Brunett, Z. (2018). Matakana Link Road, Warkworth: Archaeological Assessment.Prepared by Clough & Associates Ltd for Auckland Transport.

Jacobs (2018a). Matakana link road – Tūhonohono ki Tai, Notice of Requirement, Resource Consent Application& Assessment of Environmental Effects. Prepared for Auckland Transport.

Jacobs (2018b). Groundwater and Geotechnical Assessment of Effects. Prepared for Auckland Transport.

Jacobs (2018c). Matakana Link Road, Geotechnical Interpretative Report. Report for Auckland Transport, 28 May2018.

Leersnyder, H., Bunting, K., Parsonson, M., and Stewart, C. (2016). Erosion and sediment control guide for landdisturbing activities in the Auckland region. Auckland Council Guideline Document GD2016/005. Prepared byBeca Ltd and SouthernSkies Environmental for Auckland Council.

Wright, A. (2018). Matakana Link Road Project, Constructability Assessment Report. Prepared by Andy WrightProject Services Ltd for Auckland Transport.

Earthworks Assessment Report Auckland Transport

Project number: 60586377

Prepared for: Auckland Transport AECOM22

Appendix A ESC Drawings

T

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CULVERT 1-1

QEII RESERVE

WATERCOURSE F

WATERCOURSE E

STABILISED CONSTRUCTION

ENTRANCE

CONSTRUCTION YARD

WETLAND OUTFALL TO

WATERCOURSE

TEMPORARY WATERCOURSE

CROSSING (BRIDGE)

SEDIMENT RETENTION POND 1

LEGEND

B

PS

NOTES:

1. ALL EROSION AND SEDIMENT CONTROL MEASURES (ESCM)

WILL BE INSTALLED AND MAINTAINED IN ACCORDANCE WITH

AUCKLAND COUNCIL TECHNICAL PUBLICATION 90 (TP90) OR

SUBSEQUENT VERSIONS.

2. ALL ESCM MUST BE OPERATIONAL PRIOR TO ANY PHYSICAL

WORKS COMMENCING. A PRE-COMMENCEMENT MEETING

MUST BE HELD ON SITE WITH THE ENGINEER TO APPROVE

ESCM.

3. SPECIFIC SRP AND DEB LOCATIONS TO BE CONFIRMED ON

SITE BY SITE SUPERVISOR AND ENVIRONMENTAL TEAM.

4. SRP AND DEB STORAGE TO BE 70% LIVE STORAGE AND 30%

DEAD STORAGE.

5. THE EXACT VOLUMES OF THE SRPS AND DEBS ARE TO BE

CONFIRMED FOLLOWING CONSTRUCTION.

6. ALL PERIMETER BUNDS TO BE A MINIMUM HEIGHT OF 1.1M

UNLESS SPECIFIED.

7. ALL ESCM TO BE INSPECTED DAILY AND RECORDED.

8. SITE MONITORING TO BE UNDERTAKEN BEFORE AND

IMMEDIATELY AFTER RAIN AS WELL AS DURING HEAVY OR

PROLONGED RAIN EVENTS.

9. SEDIMENT RETENTION MEASURES WILL BE CLEANED OF

SEDIMENT WHEN 20% FULL OF SEDIMENT.

10. ESCM CAN ONLY BE REMOVED/ DECOMMISSIONED ONCE

SITE HAS BEEN STABILISED AND APPROVAL GIVEN FROM

THE ENVIRONMENTAL MANAGER OR SITE SUPERVISOR.

11. EXTENT OF WORKS IS AS SHOWN.

12. ALL LOCATIONS OR ESCM ARE INDICATIVE AND ARE TO BE

CONFIRMED ON SITE.

13. FOR CULVERT AND WETLAND OUTLET INSTALLATION REFER

TO THE EARTHWORKS ASSESSMENT REPORT FOR WORKS

WITHIN A WATERCOURSE METHODOLOGY.

14. HAUL ROAD WITHIN CARRIAGEWAY FOOTPRINT USING

SUBGRADE IMPROVEMENT LAYER BEHIND THE ADVANCING

EARTHWORKS EXCAVATIONS.

40

T

EXISTING WATERCOURSES

EARTHWORKS CATCHMENT BOUNDARY

PROPOSED CULVERTS

MLR CONSTRUCTION DESIGNATION BOUNDARY

HAUL ROAD CENTRELINE

PERIMETER DIVERSION BUND

SILT FENCE (SF)

SEDIMENT RETENTION POND (SRP)

PERMANENT SEEDING

RAIN ACTIVATED TREATMENT SYSTEM

TEMPORARY WATERCOURSE CROSSING

EARTHWORK EXTENT

FLOW DIRECTION

EARTH BUND

CONTOUR DRAIN (CD)

EXISTING CONTOURS

DIRTY WATER DIVERSION CHANNEL/BUND(DWD)

CLEANWATER DIVERSION CHANNEL (CWD)

PUMPING

LEVEL SPREADER

WORKS WITHIN A WATERCOURSE

STABILISED CONSTRUCTION ENTRANCE

PROPOSED CUT EXTENT

PROPOSED FILL EXTENT

PROPOSED DESIGNATION

RAIN ACTIVATED TREATMENT SYSTEM

SPILLWAY

PS

PS

PS

PS

PS

PS

PS

PS

PUMPING WELL

PUMPING WELL

SEDIMENT RETENTION POND 1

CATCHMENT

AREA

(ha)

REQUIRED

VOLUME

(m²)

BASE DIMENSIONS DESIGN WATER LEVEL

WIDTH

(m)

LENGTH

(m)

AREA

(m)

DEPTH

(m)

AREA

(m²)

VOLUME

(m³)

2.085 626 10.5 31.5 331 1.4 619 665

DECANTING EARTH BUND

CATCHMENT AREA

(ha)

REQUIRED VOLUME

(m²)

0.35 35

WATERCOURSE G

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QEII RESERVE

CULVERT 2-1

CULVERT 2-2

WATERCOURSE C

PS

PS

PS

PS

PS

PS

WATERCOURSE D

SEDIMENT RETENTION POND 2

LEGEND

B

PS

NOTES:

1. ALL EROSION AND SEDIMENT CONTROL MEASURES (ESCM)

WILL BE INSTALLED AND MAINTAINED IN ACCORDANCE WITH

AUCKLAND COUNCIL TECHNICAL PUBLICATION 90 (TP90) OR

SUBSEQUENT VERSIONS.

2. ALL ESCM MUST BE OPERATIONAL PRIOR TO ANY PHYSICAL

WORKS COMMENCING. A PRE-COMMENCEMENT MEETING

MUST BE HELD ON SITE WITH THE ENGINEER TO APPROVE

ESCM.

3. SPECIFIC SRP AND DEB LOCATIONS TO BE CONFIRMED ON

SITE BY SITE SUPERVISOR AND ENVIRONMENTAL TEAM.

4. SRP AND DEB STORAGE TO BE 70% LIVE STORAGE AND 30%

DEAD STORAGE.

5. THE EXACT VOLUMES OF THE SRPS AND DEBS ARE TO BE

CONFIRMED FOLLOWING CONSTRUCTION.

6. ALL PERIMETER BUNDS TO BE A MINIMUM HEIGHT OF 1.1M

UNLESS SPECIFIED.

7. ALL ESCM TO BE INSPECTED DAILY AND RECORDED.

8. SITE MONITORING TO BE UNDERTAKEN BEFORE AND

IMMEDIATELY AFTER RAIN AS WELL AS DURING HEAVY OR

PROLONGED RAIN EVENTS.

9. SEDIMENT RETENTION MEASURES WILL BE CLEANED OF

SEDIMENT WHEN 20% FULL OF SEDIMENT.

10. ESCM CAN ONLY BE REMOVED/ DECOMMISSIONED ONCE

SITE HAS BEEN STABILISED AND APPROVAL GIVEN FROM

THE ENVIRONMENTAL MANAGER OR SITE SUPERVISOR.

11. EXTENT OF WORKS IS AS SHOWN.

12. ALL LOCATIONS OR ESCM ARE INDICATIVE AND ARE TO BE

CONFIRMED ON SITE.

13. FOR CULVERT AND WETLAND OUTLET INSTALLATION REFER

TO THE EARTHWORKS ASSESSMENT REPORT FOR WORKS

WITHIN A WATERCOURSE METHODOLOGY.

14. HAUL ROAD WITHIN CARRIAGEWAY FOOTPRINT USING

SUBGRADE IMPROVEMENT LAYER BEHIND THE ADVANCING

EARTHWORKS EXCAVATIONS.

40

T

EXISTING WATERCOURSES

EARTHWORKS CATCHMENT BOUNDARY

PROPOSED CULVERTS

MLR CONSTRUCTION DESIGNATION BOUNDARY

HAUL ROAD CENTRELINE

PERIMETER DIVERSION BUND

SILT FENCE (SF)

SEDIMENT RETENTION POND (SRP)

PERMANENT SEEDING

RAIN ACTIVATED TREATMENT SYSTEM

TEMPORARY WATERCOURSE CROSSING

EARTHWORK EXTENT

FLOW DIRECTION

EARTH BUND

CONTOUR DRAIN (CD)

EXISTING CONTOURS

DIRTY WATER DIVERSION CHANNEL/BUND(DWD)

CLEANWATER DIVERSION CHANNEL (CWD)

PUMPING

LEVEL SPREADER

WORKS WITHIN A WATERCOURSE

STABILISED CONSTRUCTION ENTRANCE

PROPOSED CUT EXTENT

PROPOSED FILL EXTENT

PROPOSED DESIGNATION

SPILLWAY

RAIN ACTIVATED TREATMENT SYSTEM

SEDIMENT RETENTION POND 2

CATCHMENT

AREA

(ha)

REQUIRED

VOLUME

(m²)

BASE DIMENSIONS DESIGN WATER LEVEL

WIDTH

(m)

LENGTH

(m)

AREA

(m)

DEPTH

(m)

AREA

(m²)

VOLUME

(m³)

2.715 815 12 36 432 1.4 756 832

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WATERCOURSE B

PS

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WATERCOURSE A

STABILISED CONSTRUCTION

ENTRANCE

WETLAND OUTFALL

TO WATERCOURSE

SEDIMENT RETENTION POND 3

LEGEND

B

PS

NOTES:

1. ALL EROSION AND SEDIMENT CONTROL MEASURES (ESCM)

WILL BE INSTALLED AND MAINTAINED IN ACCORDANCE WITH

AUCKLAND COUNCIL TECHNICAL PUBLICATION 90 (TP90) OR

SUBSEQUENT VERSIONS.

2. ALL ESCM MUST BE OPERATIONAL PRIOR TO ANY PHYSICAL

WORKS COMMENCING. A PRE-COMMENCEMENT MEETING

MUST BE HELD ON SITE WITH THE ENGINEER TO APPROVE

ESCM.

3. SPECIFIC SRP AND DEB LOCATIONS TO BE CONFIRMED ON

SITE BY SITE SUPERVISOR AND ENVIRONMENTAL TEAM.

4. SRP AND DEB STORAGE TO BE 70% LIVE STORAGE AND 30%

DEAD STORAGE.

5. THE EXACT VOLUMES OF THE SRPS AND DEBS ARE TO BE

CONFIRMED FOLLOWING CONSTRUCTION.

6. ALL PERIMETER BUNDS TO BE A MINIMUM HEIGHT OF 1.1M

UNLESS SPECIFIED.

7. ALL ESCM TO BE INSPECTED DAILY AND RECORDED.

8. SITE MONITORING TO BE UNDERTAKEN BEFORE AND

IMMEDIATELY AFTER RAIN AS WELL AS DURING HEAVY OR

PROLONGED RAIN EVENTS.

9. SEDIMENT RETENTION MEASURES WILL BE CLEANED OF

SEDIMENT WHEN 20% FULL OF SEDIMENT.

10. ESCM CAN ONLY BE REMOVED/ DECOMMISSIONED ONCE

SITE HAS BEEN STABILISED AND APPROVAL GIVEN FROM

THE ENVIRONMENTAL MANAGER OR SITE SUPERVISOR.

11. EXTENT OF WORKS IS AS SHOWN.

12. ALL LOCATIONS OR ESCM ARE INDICATIVE AND ARE TO BE

CONFIRMED ON SITE.

13. FOR CULVERT AND WETLAND OUTLET INSTALLATION REFER

TO THE EARTHWORKS ASSESSMENT REPORT FOR WORKS

WITHIN A WATERCOURSE METHODOLOGY.

14. HAUL ROAD WITHIN CARRIAGEWAY FOOTPRINT USING

SUBGRADE IMPROVEMENT LAYER BEHIND THE ADVANCING

EARTHWORKS EXCAVATIONS.

40

T

EXISTING WATERCOURSES

EARTHWORKS CATCHMENT BOUNDARY

PROPOSED CULVERTS

MLR CONSTRUCTION DESIGNATION BOUNDARY

HAUL ROAD CENTRELINE

PERIMETER DIVERSION BUND

SILT FENCE (SF)

SEDIMENT RETENTION POND (SRP)

PERMANENT SEEDING

RAIN ACTIVATED TREATMENT SYSTEM

TEMPORARY WATERCOURSE CROSSING

EARTHWORK EXTENT

FLOW DIRECTION

EARTH BUND

CONTOUR DRAIN (CD)

EXISTING CONTOURS

DIRTY WATER DIVERSION CHANNEL/BUND(DWD)

CLEANWATER DIVERSION CHANNEL (CWD)

PUMPING

LEVEL SPREADER

WORKS WITHIN A WATERCOURSE

STABILISED CONSTRUCTION ENTRANCE

PROPOSED CUT EXTENT

PROPOSED FILL EXTENT

PROPOSED DESIGNATION

RAIN ACTIVATED TREATMENT SYSTEM

SPILLWAY

SEDIMENT RETENTION POND 3

CATCHMENT

AREA

(ha)

REQUIRED

VOLUME

(m²)

BASE DIMENSIONS DESIGN WATER LEVEL

WIDTH

(m)

LENGTH

(m)

AREA

(m)

DEPTH

(m)

AREA

(m²)

VOLUME

(m³)

3.345 1004 14 42 588 1.4 588 1084

5

0

5

5

60

TYPICAL SEDIMENT RETENTION POND ARRANGEMENT

SCALE 1: 200

N

LEGEND

PERIMETER DIVERSION BUND

SILT FENCE (SF)

EARTHWORK EXTENT

SEDIMENT RETENTION POND (SRP)

HAUL ROAD CENTRELINE

FLOW DIRECTION

EARTH BUND

DIRTY WATER DIVERSION CHANNEL/BUND(DWD)

CLEANWATER DIVERSION CHANNEL (CWD)

PUMPING

CONTOUR DRAIN (CD)

LEVEL SPREADER

40

EXISTING CONTOURS

RAIN ACTIVATED TREATMENT SYSTEM

MLR CONSTRUCTION DESIGNATION BOUNDARY

LEVEL SPREADER

CONTOUR DRAIN

DIRTY WATER DIVERSION CHANNEL

SEDIMENT RETENTION POND

PIPED OUTFALL

FLOATING DECANTS

SPILLWAY

RAIN ACTIVATED TREATMENT SYSTEM

MLR CONSTRUCTION

DESIGNATION BOUNDARY

EARTHWORK EXTENT

3

6

.0

0

m

1

2

.0

0

m

-

1

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

-

8

-8

-6

-

6

-

6

-4

-

4

-4

-4

-

2

-

2

-2

-

2

-

2

-2

-2

-

2

-

2

-

2

-2

2

2

2

2

2

2

2

2

4

LEVEL BANDS KEY (m)

10.0 - 12.0

8.0 - 10.0

6.0 - 8.0

4.0 - 6.0

2.0 - 4.0

0.0 - 2.0

-2.0 - 0.0

-4.0 - -2.0

-6.0 - -4.0

-8.0 - -6.0

-10.0 - -8.0

N

ANTI-SEEP COLLARSGEOTEXTILE SECURED FIRMLY TO THE

EMBANKMENT FACE

WARATAHS AND STRONG NYLON CORD TO

CONTROL LEVEL OF DECANT

GEOTEXTILE SHOULD BE LAID INTO THE POND TO A

DEPTH OF AT LEAST 500mm BELOW THE SPILLWAY

INVERT

RIP-RAP PLACED AT POUND OUTLET WITH GEOTEXTILE

PLACED UNDERNEATH

IF NECESSARY PLACE A 30° BEND TO KEEP LOWER

DECANT WELL AWAY FROM UPPER DECANT

CROSS SECTION

Scale: NTS

SEDIMENT RETENTION POND DETAILS

PLAN

Scale: NTS

A

A

2000mm

WARATAHS PLACED EITHER SIDE

OF DECANT ARM AS ALTERNATIVE

MEANS OF SECURING DECANT

WIRE LIMITING VERTICAL

MOVEMENT OF DECANT

STANDARD

TEE JOINT

2000mm

300mm

FLEXIBLE RUBBER JOINTS GLUED

AND CLAMPED-TWO JOINTS TO BE

USED ONLY FOR LOWER DECANT

ATTACH 1.8m LONG

WARATAH TO WEIGHT DECANT

(REF. SECTION A-A)

STANDARD END CAPS

WIRE OR STEEL STRAPS TO

JOIN DECANT AND FLOAT

STANDARD WARATAH PLACEMENT

AT EITHER END OF THE DECANT

DECANT

SINGLE WARATAH FIXED FIRMLY

BEHIND CABLE TIES/STRAPS

REQUIRED TO WEIGHT DECANT

FLOAT

NYLON CORD TO BE TIED THROUGH

THE END HOLES IN DECANT AND

SECURED TO THE WARATAH

SECTION A-A

SEDIMENT RETENTION POND - DECANT DETAILS

PINNED GEOTEXTILE OVERLAID WITH LARGE ROCK

TO BREAK UP FLOW

MANHOLE TO ACT AS PRIMARY SPILLWAY

ALL BARE SURFACES TO BE

STABILISED WITH VEGETATION

EXTRA CREST WIDTH MAY BE REQUIRED TO PROVIDE

FOR MACHINERY ACCESS FOR CLEANING OUT

LEVEL SPREADER FULL WIDTH OF INLET END,

STABILISED FROM THE BEGINNING OF THE INLET TO

THE POND INVERT AND APPROPRIATE SOFT MATTING

GEOTEXTILE. LEVEL SPREADER TO BE 100-150mm

ABOVE THE INVERT LEVEL OF THE SPILLWAY.

EMERGENCY SPILLWAY IS TO BE WIDE, SHALLOW AND

LEVEL. WHERE POSSIBLE OVER THE EXISTING GROUND

RETAINING THE EXISTING GRASS COVER. BARE AREAS TO

BE STABILISED WITH CONCRETE OR SIMILAR.

RUNOFF DIVERSION CHANNEL / BUND TO

ENSURE ALL FLOW ENTERS AT THE INLET END

150mmØ RISER

2x RUBBER COUPLINGS TO PROVIDE ADDITIONAL

RANGE

150-100mm REDUCTION

POURED CONCRETE ANTI-SEEP COLLAR

100mm DIA. DISCHARGE PIPE LAID AT 1

OR 2% GRADIENT

POURED CONCRETE

ANTI-SEEP COLLAR

POND BATTERS 2:1 TO 3:1

SPILLWAY COMPACTED & SMOOTHED TO ELIMINATE

ALL VOIDS PRIOR TO LAYING AND PINNING

APPROPRIATE GEOTEXTILE/CONCRETE

WIDTH OF TOP EMBANKMENT SHOULD BE WIDE ENOUGH

TO ENSURE MACHINERY ACCESS FOR DE-SLUDGING OF

POND, IF THERE ARE NO OTHER ACCESS POINTS

AVAILABLE.

MIN

.

FR

EE

BO

AR

D

30

0m

m

30

0m

m

60° Y JUNCTION

UP

PE

R D

EC

AN

TS

E

XT

EN

T O

F

TR

AV

EL

IS

O

VE

R 5

0%

O

F

TH

E L

IV

E S

TO

RA

GE

D

EP

TH

SEE

DECANT

DETAIL

WARATAH STAKE

POND BASE LEVEL

DE

AD

ST

OR

AG

E

40

0m

m

LO

WE

R D

EC

AN

TS

E

XT

EN

T O

F

TR

AV

EL

IS

O

VE

R 1

00

% O

F

TH

E L

IV

E S

TO

RA

GE

D

EP

TH

- V

AR

IA

BL

E U

P T

O 1

00

0m

m

30

0m

m

min

.

2000mm min

10

0m

m

FLO

W

30

0m

m

FLO

W

50

0m

m

25

0m

m

2000mm

ORIGINAL GROUND

EXISTING VEGETATION TO

REMAIN UNDISTURBED

SPECIFIC DESIGN

CROSS SECTION

COMPACTED EARTH BUND

HYDROSEEDED & MULCHED

OR TOPSOILED & SEEDED

POSITIONING OF CONTOUR DRAINS

30

40

50

SPACING OF CONTOUR DRAINS (m)

15

10

5

SLOPE OF SITE(%)

ORIGINAL GRADE

DE

SIG

N F

LO

W

DE

PT

H

3:1 OR FLATTER

2:1 OR FLATTER

COMPACTED EMBANKMENT

COMPACTED EARTH BUND

2000mm MAX.

40

0m

m M

IN

.

HE

IG

HT

O

F G

EO

TE

XT

IL

E

20

0m

m M

IN

.

GROUND LEVEL

STEEL STANDARDS SUCH AS

WARATAHS OR STANDARD

WOODEN FENCE POSTS DRIVEN

A MIN. OF 400mm INTO THE

GROUND FLOW FLOW

TRENCH GEOTEXTILE A

MIN. OF 200mm INTO

THE GROUND

40

0m

m M

IN

.

HE

IG

HT

O

F G

EO

TE

XT

IL

E

40

0m

m M

IN

.

PO

ST

D

EP

TH

GEOTEXTILE FIXED FIRMLY

TO POST/WARATAH

FLOW

TRENCH GEOTEXTILE 200mm

MIN. TO GROUND

COMPACTED BACKFILL

STAPLE

STAPLE

STAPLE

OVERLAP WOODEN BATTENS

SECTION A

SECTION B

PROVIDE LEAK PROOF JOINT AT

THE JUNCTION OF THE RETURN

AND MAIN SILT FENCE ALIGNMENT

ENDS OF RETURN

WIRED BACK TO

STAKE OR WARATAH

WHERE REQUIRED RETURNS A

MINIMUM OF 2 METRES IN

LENGTH TO REDUCE VELOCITY

ALONG THE SILT FENCE AND

PROVIDE INTERMEDIATE\IMPOUNDMENT

SILT FENCE DESIGN CRITERIA

20

30

40

SLOPE LENGTH (m) (MAX.)

20-33%

10-20%

2-10%

SLOPE STEEPNESS %

UNLIMITEDFLATTER THAN 2%

SPACING OF RETURNS (m) SILT FENCE LENGTH (m) (MAX.)

N/A UNLIMITED

>50%

33-50% 15

6

40

50

60

30

20

150

230

300

75

40

CLEAR WATER RUNOFF DIVERSION BUND

CROSS SECTIONPERSPECTIVE VIEW

SILT FENCE

CROSS SECTION

RUNOFF DIVERSION CHANNEL

SILT FENCE - ELEVATION

CROSS SECTION STANDARD FABRIC JOINT

CROSS SECTION - CONTOUR DRAIN

SILT FENCE SILT FENCE

10

00

mm

A

PP

RO

X.

25

0m

m

SPILLWAY

PERFORATED PIPE FIXED

TO WARATAH STAKE

160mm NON-PERFORATED PIPE THROUGH BUND

STABILISED OUTLET

SPILLWAY STABILISED WITH GEOTEXTILE

CROSS SECTION

DECANTING EARTH BUND

Earthworks Assessment Report Auckland Transport

Project number: 60586377

Prepared for: Auckland Transport AECOM23

Appendix B TP108 and SRP Calculations

Job Name:

Job No:

Date:

Calculations By:

SEDIMENT RETENTION POND SIZING

Width Length Area

(3 x width)

(m²) (m³) (m) (m) (m) (m²) (m²) (m³)

Matakana Link Road

1 20850 626 10.5 31.5 1.4 331 619 665

2 27150 815 12.0 36.0 1.4 432 756 832

3 33450 1004 14.0 42.0 1.4 588 960 1084

Sediment Retention Pond Sizing

Sediment

Retention

Pond No.

Catchment

Area

Required

Volume

Base Dimensions Area at

selected

depth

above base

Volume

provided at

selected

depth

Selected

Depth

Earthworks Catchment

Matakana Link Road

60586377

31 August 2018

Duane Rollo

Job Name:

Job No:

Date:

Calculations By:

PEAK FLOW RUNOFF CALCULATIONS FOR CULVERT CONSTRUCTION

Circular Bridge Weighted

C

0.95 0.50

Impervious Pervious (Tc) 1yr 20yr 1yr 20yr

(mm) (m) (m²) (m²) (m²) (mins) (mm) (mm) (m³/s) (m³/s)

Matakana Link Road

1-1 E 1200 Dia 0 49500 49500 0.50 10 74.40 133.80 0.51 0.92

2-1 D 900 Dia 0 27800 27800 0.50 10 74.40 133.80 0.29 0.52

2-2 C 750 Dia 0 20850 20850 0.50 10 74.40 133.80 0.22 0.39

3-1 B 600 Dia 0 12400 12400 0.50 10 74.40 133.80 0.13 0.23

Matakana Link Road

60586377

06 September 2018

Duane Rollo

Crossing Data Hydrological Data

Culvert

Ref.

Watercourse

Ref.

Catchment Area (A) Time of

Conc.

Rainfall Intensity (I) Peak Flowrate (Q)

Runoff Coefficients (C) Total

Catchment

Area

ESTIMATION OF SEDIMENT YIELD BY THE UNIVERSAL SOIL LOSS EQUATION

An Empirical Method to Estimate Sheet and Rill Erosion from Land

PROJECT No : 60586377 BY : D.Rollo DATE : 10 September 2018 CHECKED :

SITE DESCRIPTION : Matakana Link Road - Catchment to Sediment Retention Pond 1

Catchment Size = 2.085 ha

Work Duration = 4.00 months => 0.333 Years

Working Area = 2.085 ha

WORKING EQUATION : A = R K LS C P where A = soil loss (tonnes/ha/year)

- Rainfall erosion index (R)

p = 68.1 mm/ 6 hrs

R = 152 where, R = 0.00828*(p^2.2)*1.7

- Soil erodibility index (K) (From triangular nomograph)

Working Area Remaining Area

Assume 7 % Sand 7 % Sand

7 % Silt 7 % Silt

86 % Clay 86 % Clay

100 0 % granular 0 % granular

0 % organic 0 % organic

From Triangular Nomograph K = 0.104

Correction for organic content, K = 0.164

K = 0.22 K = 0

- Slope length and steepness factor (LS)

Working Area Remaining Area

Length = 110 m Length = 0 m

Slope = 10 % Slope = 0 % 1 in 10.0

LS = 2.60 LS = 0.00

- Vegetation cover factor and Erosion control practice factor (C and P)

Assume : Working Area Bare soil - compacted and smoothed

Remaining Area Pasture

Working Area Remaining Area

C = 1 C = 0P = 1.32 P = 0

The USLE predicts the total yield of sediment generated but makes no allowance for that retained on site. A Sediment Delivery Ratio (SDR)

must be selected. American sources state that SDR rates range mostly from 0.1 to 0.7 (N.Y. Guidelines for Urban Erosion and Sediment Control).

Assume SDR = 0.7

Sediment control efficiency = 75 %

Est. Gross Sediment Net

Section USLE Parameters A Area Works Sediment Sediment Control Sediment

R K LS C P Soil Loss (ha) Duration Yield Delivery Efficiency Loss

(t/ha/yr) (Years) (tonnes) Ratio (%) (tonnes)

Working 152 0.21648 2.60 1 1.32 112.9 2.085 0.333 78.5 0.7 75 13.7

Remaining 152 0 0.00 0 0 0.0 0 0.333 0.0 0.7 75 0.0

Sediment Generation Potential (tonnes) 78.5

Estimated Total Net Sediment Loss (tonnes) 13.7

::

ESTIMATION OF SEDIMENT YIELD BY THE UNIVERSAL SOIL LOSS EQUATION

An Empirical Method to Estimate Sheet and Rill Erosion from Land

PROJECT No : 60586377 BY : D.Rollo DATE : 10 September 2018 CHECKED :

SITE DESCRIPTION : Matakana Link Road - Catchment to Sediment Retention Pond 2

Catchment Size = 2.72 ha

Work Duration = 3.00 months => 0.250 Years

Working Area = 2.72 ha

WORKING EQUATION : A = R K LS C P where A = soil loss (tonnes/ha/year)

- Rainfall erosion index (R)

p = 68.1 mm/ 6 hrs

R = 152 where, R = 0.00828*(p^2.2)*1.7

- Soil erodibility index (K) (From triangular nomograph)

Working Area Remaining Area

Assume 7 % Sand 20 % Sand

7 % Silt 7 % Silt

86 % Clay 86 % Clay

100 0 % granular 0 % granular

0 % organic 0 % organic

From Triangular Nomograph K = 0.104

Correction for organic content, K = 0.164

K = 0.22 K = 0

- Slope length and steepness factor (LS)

Working Area Remaining Area

Length = 420 m Length = 0 m

Slope = 6 % Slope = 0 % 1 in 16.7

LS = 2.50 LS = 0.00

- Vegetation cover factor and Erosion control practice factor (C and P)

Assume : Working Area Bare soil - compacted and smoothed

Remaining Area Pasture

Working Area Remaining Area

C = 1 C = 0P = 1.32 P = 0

The USLE predicts the total yield of sediment generated but makes no allowance for that retained on site. A Sediment Delivery Ratio (SDR)

must be selected. American sources state that SDR rates range mostly from 0.1 to 0.7 (N.Y. Guidelines for Urban Erosion and Sediment Control).

Assume SDR = 0.7

Sediment control efficiency = 75 %

Est. Gross Sediment Net

Section USLE Parameters A Area Works Sediment Sediment Control Sediment

R K LS C P Soil Loss (ha) Duration Yield Delivery Efficiency Loss

(t/ha/yr) (Years) (tonnes) Ratio (%) (tonnes)

Working 152 0.21648 2.50 1 1.32 108.3 2.715 0.250 73.5 0.7 75 12.9

Remaining 152 0 0.00 0 0 0.0 0 0.250 0.0 0.7 75 0.0

Sediment Generation Potential (tonnes) 73.5

Estimated Total Net Sediment Loss (tonnes) 12.9

::

ESTIMATION OF SEDIMENT YIELD BY THE UNIVERSAL SOIL LOSS EQUATION

An Empirical Method to Estimate Sheet and Rill Erosion from Land

PROJECT No : 60586377 BY : D.Rollo DATE : 10 September 2018 CHECKED :

SITE DESCRIPTION : Matakana Link Road - Catchment to Sediment Retention Pond 3

Catchment Size = 3.35 ha

Work Duration = 3.00 months => 0.250 Years

Working Area = 3.35 ha

WORKING EQUATION : A = R K LS C P where A = soil loss (tonnes/ha/year)

- Rainfall erosion index (R)

p = 68.1 mm/ 6 hrs

R = 152 where, R = 0.00828*(p^2.2)*1.7

- Soil erodibility index (K) (From triangular nomograph)

Working Area Remaining Area

Assume 7 % Sand 7 % Sand

7 % Silt 7 % Silt

86 % Clay 86 % Clay

100 0 % granular 0 % granular

0 % organic 0 % organic

From Triangular Nomograph K = 0.104

Correction for organic content, K = 0.164

K = 0.22 K = 0

- Slope length and steepness factor (LS)

Working Area Remaining Area

Length = 500 m Length = 0 m

Slope = 5 % Slope = 0 % 1 in 20.0

LS = 2.17 LS = 0.00

- Vegetation cover factor and Erosion control practice factor (C and P)

Assume : Working Area Bare soil - compacted and smoothed

Remaining Area Pasture

Working Area Remaining Area

C = 1 C = 0P = 1.32 P = 0

The USLE predicts the total yield of sediment generated but makes no allowance for that retained on site. A Sediment Delivery Ratio (SDR)

must be selected. American sources state that SDR rates range mostly from 0.1 to 0.7 (N.Y. Guidelines for Urban Erosion and Sediment Control).

Assume SDR = 0.7

Sediment control efficiency = 75 %

Est. Gross Sediment Net

Section USLE Parameters A Area Works Sediment Sediment Control Sediment

R K LS C P Soil Loss (ha) Duration Yield Delivery Efficiency Loss

(t/ha/yr) (Years) (tonnes) Ratio (%) (tonnes)

Working 152 0.21648 2.17 1 1.32 94.1 3.345 0.250 78.7 0.7 75 13.8

Remaining 152 0 0.00 0 0 0.0 0 0.250 0.0 0.7 75 0.0

Sediment Generation Potential (tonnes) 78.7

Estimated Total Net Sediment Loss (tonnes) 13.8

::

ESTIMATION OF SEDIMENT YIELD BY THE UNIVERSAL SOIL LOSS EQUATION

An Empirical Method to Estimate Sheet and Rill Erosion from Land

PROJECT No : 60586377 BY : D.Rollo DATE : 10 September 2018 CHECKED :

SITE DESCRIPTION : Matakana Link Road - Catchment to Decanting Earth Bund

Catchment Size = 0.35 ha

Work Duration = 1.50 months => 0.125 Years

Working Area = 0.35 ha

WORKING EQUATION : A = R K LS C P where A = soil loss (tonnes/ha/year)

- Rainfall erosion index (R)

p = 68.1 mm/ 6 hrs

R = 152 where, R = 0.00828*(p^2.2)*1.7

- Soil erodibility index (K) (From triangular nomograph)

Working Area Remaining Area

Assume 7 % Sand 7 % Sand

7 % Silt 7 % Silt

86 % Clay 86 % Clay

100 0 % granular 0 % granular

0 % organic 0 % organic

From Triangular Nomograph K = 0.104

Correction for organic content, K = 0.164

K = 0.22 K = 0

- Slope length and steepness factor (LS)

Working Area Remaining Area

Length = 50 m Length = 0 m

Slope = 20 % Slope = 0 % 1 in 5.0

LS = 5.23 LS = 0.00

- Vegetation cover factor and Erosion control practice factor (C and P)

Assume : Working Area Bare soil - compacted and smoothed

Remaining Area Pasture

Working Area Remaining Area

C = 1 C = 0P = 1.32 P = 0

The USLE predicts the total yield of sediment generated but makes no allowance for that retained on site. A Sediment Delivery Ratio (SDR)

must be selected. American sources state that SDR rates range mostly from 0.1 to 0.7 (N.Y. Guidelines for Urban Erosion and Sediment Control).

Assume SDR = 0.7

Sediment control efficiency = 50 %

Est. Gross Sediment Net

Section USLE Parameters A Area Works Sediment Sediment Control Sediment

R K LS C P Soil Loss (ha) Duration Yield Delivery Efficiency Loss

(t/ha/yr) (Years) (tonnes) Ratio (%) (tonnes)

Working 152 0.21648 5.23 1 1.32 226.8 0.35 0.125 9.9 0.7 50 3.5

Remaining 152 0 0.00 0 0 0.0 0 0.125 0.0 0.7 50 0.0

Sediment Generation Potential (tonnes) 9.9

Estimated Total Net Sediment Loss (tonnes) 3.5

::

Earthworks Assessment Report Auckland Transport

Project number: 60586377

Prepared for: Auckland Transport AECOM24

Appendix C Accidental Discovery Protocols

AUP(OP) E11.6.1 Accidental Discovery Rule29 August 2018p:\605x\60586377\6. draft docs\6.1 reports\3rd draft 26.09-final draft\ew\appendix c\appc- accidental protocol.docx 1 of 2

AUP(OP) E11.6.1 Accidental Discovery Rule

E11.6.1. Accidental discovery rule

(1) Despite any other rule in this Plan permitting earthworks or land disturbance or any activityassociated with earthworks or land disturbance, in the event of discovery of sensitive material which isnot expressly provided for by any resource consent or other statutory authority, the standards andprocedures set out in this rule must apply.

(2) For the purpose of this rule, ‘sensitive material’ means:

(a) human remains and kōiwi;

(b) an archaeological site;

(c) a Māori cultural artefact/taonga tuturu;

(d) a protected New Zealand object as defined in the Protected Objects Act 1975 (including any fossilor sub-fossil);

(e) evidence of contaminated land (such as discolouration, vapours, asbestos, separate phasehydrocarbons, landfill material or significant odour); or

(f) a lava cave greater than 1m in diameter on any axis.

(3) On discovery of any sensitive material, the owner of the site or the consent holder must take thefollowing steps:

Cease works and secure the area

(a) immediately cease all works within 20m of any part of the discovery, including shutting down allearth disturbing machinery and stopping all earth moving activities, and in the case of evidence ofcontaminated land apply controls to minimise discharge of contaminants into the environment;

(b) secure the area of the discovery, including a sufficient buffer area to ensure that all sensitivematerial remains undisturbed.

Inform relevant authorities and parties

(c) inform the following parties immediately of the discovery:

(i) the New Zealand Police if the discovery is of human remains or kōiwi;

(ii) the Council in all cases;

(iii) Heritage New Zealand Pouhere Taonga if the discovery is an archaeological site, Māori culturalartefact, human remains or kōiwi; and

(iv) Mana Whenua if the discovery is an archaeological site, Māori cultural artefact, or kōiwi.

Wait for and enable inspection of the site

(d) wait for and enable the site to be inspected by the relevant authority or agency:

(i) if the discovery is human remains or kōiwi the New Zealand Police are required to investigate thehuman remains to determine whether they are those of a missing person or are a crime scene. Theremainder of this process will not apply until the New Zealand Police confirm that they have no furtherinterest in the discovery; or

(ii) if the discovery is of sensitive material, other than evidence of contaminants, a site inspection forthe purpose of initial assessment and response will be arranged by the Council in consultation withHeritage New Zealand Pouhere Taonga and appropriate Mana Whenua representatives; or

(iii) if the discovery is evidence of contaminants, a suitably qualified and experienced person isrequired to complete an initial assessment and provide information to the Council on the assessmentand response.

AUP(OP) E11.6.1 Accidental Discovery Rule29 August 2018p:\605x\60586377\6. draft docs\6.1 reports\3rd draft 26.09-final draft\ew\appendix c\appc- accidental protocol.docx 2 of 2

(e) following site inspection and consultation with all relevant parties (including the owner and consentholder), the Council will determine the area within which work must cease, and any changes tocontrols on discharges of contaminants, until the requirements of step E11.6.1(3)(f) are met.

Recommencement of work

(f) work within the area determined by the Council at step E11.6.1(3)(e) must not recommence until allof the following requirements, so far as relevant to the discovery, have been met:

(i) Heritage New Zealand has confirmed that an archaeological authority has been approved for thework or that none is required;

(ii) any required notification under the Protected Objects Act 1975 has been made to the Ministry forCulture and Heritage;

(iii) the requirements of Section E30 Contaminated land and/or the National Environmental Standardsfor Assessing and Managing Contaminants in Soil to Protect Human Health 2011 have been met;

(iv) any material of scientific or educational importance must be recorded and if appropriate recoveredand preserved;

(v) if the discovery is a lava cave as outlined in E11.6.1(2)(f) above and if the site is assessed to beregionally significant, reasonable measures must be taken to minimise adverse effects of the works onthe scientific values of the site; and

(vi) where the site is of Māori origin and an authority from Heritage New Zealand Pouhere Taonga isnot required the Council will confirm, in consultation with Mana Whenua, that:

• any kōiwi have either been retained where discovered or removed in accordance with the appropriatetikanga; and

• any agreed revisions to the planned works to be/have been made in order to address adverse effectson Māori cultural values.

(vii)resource consent has been granted to any alteration or amendment to the earthworks or landdisturbance that may be necessary to avoid the sensitive materials and that is not otherwise permittedunder the Plan or allowed by any existing resource consent.

(viii) that there are no requirements in the case of archaeological sites that are not of Māori origin andare not covered by Heritage New Zealand Pouhere Taonga Act 2014.

Earthworks Assessment Report Auckland Transport

Project number: 60586377

Prepared for: Auckland Transport AECOM25

Appendix D Kauri Dieback Operating Procedure for MatakanaLink Road Project

P O Box 2828, Shortland Street, Auckland 1140. Telephone: (09) 379-9417 Facsimile (09) 307-6409Website: www.bioresearches.co.nz

Appendix VI Kauri Dieback Standard Operating Procedure

KAURI DIEBACK OPERATING PROCEDURE:TUHONOHONO KI TAI / MATAKANA LINK PROJECT

PREPARED BY: SARAH KILLICK

BIORESEARCHES GROUP LTD

68 BEACH ROAD, AUCKLAND

SARAHKILLICK@BIORESEARCHES.CO.NZ

FOR: NEW ZEALAND TRANSPORT AUTHORITY (NZTA)

DATE: OCTOBER 25TH, 2017

REFERENCE: BIORESEARCHES (2017). KAURI DIEBACK OPERATING PROCEDURE: MATAKANA LINK

PROJECT.

P O Box 2828, Shortland Street, Auckland 1140. Telephone: (09) 379-9417 Facsimile (09) 307-6409Website: www.bioresearches.co.nz

INTRODUCTION

Kauri dieback is a disease cause by a fungus-like organism, Phytophthora agathidicida (PTA). Unlike

fungi, PTA is made of cellulose, rather than chitin, and forms a motile ‘tail’ which allows for movement.

This motility increases the potential movement and spread risk of Phytophthora species. Although

there are species of Phytophthora native to New Zealand, these have not been found to cause

significant disease within New Zealand forests, despite having serious implications internationally

(Scott & Williams, 2014). Conversely, PTA has been identified as a serious threat to kauri forests in New

Zealand, and has been directly associated with the disease and death of kauri (Agathis australis). Kauri

do not produce cones until the trees are 15 – 50 years old, depending on the tree, and cones produced

by trees under 20 years old are often infertile (Ogden et al., 1987). Although kauri themselves are not

a threatened species, this slow maturation process and the extent of historical logging has placed kauri

forests as threatened under the IUCN threat classification system (Singers et al., 2017).

Infection of a kauri with PTA causes damage to the vascular tissues, preventing the tree from accessing

the water and nutrients that it requires. Infected individuals may display symptoms of stress, including

leaf yellowing and loss, branch loss, and eventually, death. There is no known cure for PTA, although

there has been some success with extending tree life post-infection by injecting phosphorus directly

into the tree trunk (Horner et al., 2015). Because of the high risk and cost of PTA to kauri and potentially

other species across New Zealand, it is extremely important to minimize risk of spread.

This Operating Procedure has been written specifically for the Matakana Link Project (‘Project’) site in

Rodney, Auckland, and has been adapted from Auckland Council’s Standard Operating Procedures

(2017) and a recent review of PTA detection methods (Singh et al., 2017). The Project includes the

construction of a highway, which is proposed to bisect a kauri forest. PTA infection has not yet been

identified on site, however a nearby forest (c. 6.5 km) has confirmed PTA presence

(www.kauridieback.co.nz). Although the proposed road design will result in the loss of kauri forest, it

is of critical importance to limit the loss of kauri forests wherever possible by ensuring that PTA, if

present, is not spread into healthy forests.

PTA is an unwanted organism under the Biosecurity Act 1993. In accordance with section 52 ofthat act, no person shall knowingly communicate, cause to be communicated, release, cause tobe released, or otherwise spread the organism.

P O Box 2828, Shortland Street, Auckland 1140. Telephone: (09) 379-9417 Facsimile (09) 307-6409Website: www.bioresearches.co.nz

IDENTIFICATION OF PTA-INFECTION

Symptoms of Infection

Figure 17: Signs of PTA infection include gummosis (left, photo credit Zoe Lyle), and branch dieback and eventual tree death (right,kauridieback.co.nz)

· Foliage yellowing or loss· Branch dieback or loss· Excessive exudation of gum (gummosis) on lower trunk· Tree death.

A lack of symptoms is not evidence of non-infection. Infected individuals may take a prolonged periodto develop symptoms, and asymptomatic hosts that are not directly affected may still host thepathogen and spread it to other individuals (known as ‘silent hosts’). Data from preliminarypathogenicity trials strongly suggest other species (including tanekaha (Phyllocladus trichomanoides))are also susceptible to PTA (Ryder, Waipara, & Burns, 2016). Although further research in this area isrequired, the precautionary principle should be applied and all vegetation should be assumedsusceptible unless proven otherwise. Therefore, if any of the above symptoms are noticed in anyspecies on site, follow through with soil testing and, if PTA is suspected, notify the Auckland Council.Any positive result from PTA testing must be reported to MPI immediately.

Soil Testing

To sample the soil for PTA testing, find a site 1 m away from the kauri trunk, on the uphill side. Usinga clean metal soil corer, collect 1 kg of soil, and place in a sealable plastic bag. In a separate bag, placea 50 ml bottle of frozen water. Seal the bag containing the water bottle, and wrap the bag around thebottle several times to provide temperature protection. Place the wrapped bottle inside of the soilbag, and then place the sealed soil bag into a box cooler. Keep the cooler out of the sun as much aspossible, and courier to Scion or another approved testing facility for testing immediately. Do not takesamples at the end of the week or before a long weekend, as the samples may not be able to beprocessed before sample deterioration.

P O Box 2828, Shortland Street, Auckland 1140. Telephone: (09) 379-9417 Facsimile (09) 307-6409Website: www.bioresearches.co.nz

The most common form of soil testing is the baiting method, where the soil samples are dried fully andthen moistened with distilled water to encourage zoospore production. The samples are then flooded,and then a bait (such as lupin radicals) are inserted. From the bait, the Phytophthora must be isolatedand grown on a specific media. Because this process relies upon the colonization and growth of theorganism, testing takes approximately 20 days. Recent research has also found that this method canprovide an increased risk of a false-negative result, where PTA is present in soils but undetected, whencompared to qPCR genetic analysis. Therefore, where possible, qPCR testing should be utilized.

PTA testing should be undertaken on site for preliminary testing prior to works commencing; followingthis, if PTA is suspected (i.e. kauri are presenting with PTA symptoms), Auckland Council should benotified immediately.

Notification

Phytophthora agathidicida is an Unwanted Organism under the Biosecurity Act 1993. You must notifyAuckland Council and MPI immediately if PTA is found on or around the project site. Instructions givenfrom the Auckland Council and/or MPI must be complied with by all personnel at all times.

SANITATION AND SPREAD PREVENTION

Sterigene

PTA spores can be removed by scrubbing thoroughly with warm water alone providing the equipmentis allowed to dry completely afterward; however, the use of Sterigene (formerly known as Trigene) ispreferred to more thoroughly disinfect shoes and equipment. Sterigene cannot be used to kill sporeswithin soil.

Sterigene is purchased as a concentrate, and should be made up into a 2% solution. Whilst theconcentrate has a shelf life of 3 years, the solution is only effective for six months, after which freshsolution will be required. Expired Sterigene can be returned to an Auckland Council or Department ofConservation office for disposal, or used as a general detergent (for non-PTA purposes). If necessary,it may be discarded on areas of lawn or gravel, but this should not occur during wet weather.

General Works

Works and vehicle movement within and in the areas immediately surrounding forest containing kaurishould be avoided wherever practicable. Where not practicable, avoid undertaking works in wetweather where there is an increased risk of zoospore production and movement. If PTA is suspected,the Auckland Council should be notified, and works in the affected areas ceased until the Council hasprovided clearance for works re-commencement.

P O Box 2828, Shortland Street, Auckland 1140. Telephone: (09) 379-9417 Facsimile (09) 307-6409Website: www.bioresearches.co.nz

Footwear and Equipment

Upon entering and exiting the kauri forest, each person must scrub the soles of their footwear with adry brush to loosen and remove soil, and then spray with a 2% solution of Sterigene. In addition,footwear should be re-brushed and sprayed when moving between areas of kauri, within the site.

Equipment that may come into contact with plant material or soil should also be sanitised upon entryto and exit from the site using the brush and Sterigene spray method. Equipment should be allowedto dry for at least 2 minutes, but preferably until completely dry, before transportation.

To assist with this, all on-site vehicles should hold a personal phytosanitary kit, including a 500ml spraybottle of 2% Sterigene solution and a scrubbing brush in a sealed plastic bag. At all site entries / sign inpoints, a scrubbing bush, 4 L jerry can of 2% Sterigene solution and a 1 L spray bottle of the Sterigenesolution shall be kept and maintained in a suitable container. Signage instructing all visitors andworkers passing this point to sanitize footwear and equipment that has or may come into contact withsoil or vegetation should be visible at all times.

Vehicles and Heavy Equipment

Where possible, vehicles and heavy machinery should remain on-site for the duration of the project tolimit spread risk. Operators are responsible for ensuring machinery and vehicles are free of mud andsoil on tyres, mud flaps, body, and underbody when entering an area containing kauri and whenmoving from one area of kauri to another. Interior mats can also be a point of transfer, and should becleaned regularly.

In addition to the personal Sterigene kit (Section 3.3), vehicles entering areas of kauri forest shouldhold tools to enable cleaning. Although these will vary depending on the vehicle, cleaning toolsgenerally include scrubbing brushes and/or brooms to remove soil and plant material from thevehicles’ exterior, a steel rod for dislodging clumps of soil, and equipment for applying disinfectant.

Wash-down sites should be provided, and positioned on a concrete or gravel area with good drainage.After mud, soil, and vegetation has been removed by brush and/or rod, the vehicle should be sterilisedwith a 2% Sterigene solution. The vehicle should be as clean as possible before the Sterigene is appliedto allow thoroughly decontamination. After the vehicle is cleaned, allow to dry for 1 – 10 minutes, andwash and sterilise tools (brushes and rods) used for vehicle cleaning. Do not allow water or Sterigenesolution to pool on ground. For smaller vehicles, it is sufficient to dry brush of all visible mud, and thentake the vehicle through a commercial car wash. Always undertake a final visual inspection of thevehicles and machinery to ensure there is no remaining soil, mud, or plant material before the vehicleis moved.

Felled Tree Disposal

Kauri and other native trees should be protected from felling wherever practicable. Where notpracticable, the felled trees must not be disposed of in the remaining forest as doing so may spread

P O Box 2828, Shortland Street, Auckland 1140. Telephone: (09) 379-9417 Facsimile (09) 307-6409Website: www.bioresearches.co.nz

PTA from potentially infected sites to the retained forested areas. Instead, all plant matter should bedisposed of at a facility approved by the National Kauri Dieback Programme. Currently, the onlyAuckland facility approved for receiving PTA-infected organic material is EnviroWaste Hampton Downs(136 Hampton Downs Road, Te Kauwhata). EnviroWaste will need to be provided with at least 24hours’ notice to accept site waste, which can be done by calling (09) 622-8829. Vehicles used fortransporting organic matter need to be securely covered as to prevent the release of potentiallyinfected material en route. The vehicle should be thoroughly sanitized as per the methods outlined inSection 3.3 above.

Soil Movement

No soil or organic matter from the project site shall be moved into the remaining forested areas.Current testing methodologies have been found to under-report the presence of PTA (Singh et al.2017). This means that a PTA-negative result should be treated as a non-positive, rather than anegative. At all times, the precautionary approach should be taken, and the soil within the forestedarea of the project shall be treated as potentially contaminated.

If any soil material cannot be left in situ, then it must be disposed off-site in a landfill approved by theNational Kauri Dieback Programme. Currently, the two approved facilities within Auckland are:

· Ridge Road Quarries (for soil only), in Bombay; and· EnviroWaste, Hampton Downs.

For transportation off-site, the soil must be kept in a fully covered truck trailer, to prevent the droppingof contaminated soil during the commute. The truck should be sanitized thoroughly, as per Section 3.3above.

SUMMARY AND RECOMMENDATIONS

The inclusion of a section of kauri podocarp broadleaved forest in the proposed Matakana Link Projectincreases risk of spreading the unwanted organism, Phytophthora agathidicida (PTA). Although PTAhas not been recorded within the affected forest, there is a confirmed PTA-infected kauri forestnearby, increasing the need for vigilance. PTA is a pathogen spread by movement of soil, water, andvegetation. Once a kauri is infected with PTA, it is almost always fatal, and there is currently no knowncure. Although kauri are not a threatened species, the ecosystem present (kauri podocarp broadleavedforest) is much reduced from its historic extent, and is classified as Endangered (Singers et al. 2017).

PTA is an unwanted organism under the Biosecurity Act 1993. In accordance with this Act, it is illegalto spread the organism. The best course of action is to avoid works within kauri forest. If this is notpracticable, measures must be undertaken to ensure that PTA, if present, is not spread. Vehicles,machinery, and footwear should be sterilised before entering and exiting the site, as well as betweenareas of kauri. Soil and organic matter, if removed, must be disposed of at approved disposal facilities.At no point should soil, plant material, or any organic matter be disposed of in the retained forest.Kauri on site, and in the surrounding retained forest should be monitored for symptoms of infection.If PTA is suspected, the Auckland Council must be notified, and works in the area surrounding kaurishould be halted until further notice. Any positive PTA test must also result in immediate MPInotification.

P O Box 2828, Shortland Street, Auckland 1140. Telephone: (09) 379-9417 Facsimile (09) 307-6409Website: www.bioresearches.co.nz

REFERENCES

Auckland Council. (2017). Standard Operating Procedures for Kauri Dieback (draft).Bioresearches Ltd. (2017). Kauri Dieback Operating Procedure.Horner, I. J., Hough, E. G., & Horner, M. B. (2015). Forest efficacy trials on phospite for control of kauri

dieback. In New Zealand Plant Protection2 (pp. 7–12).Ibáñez, I., Katz, D. S. W., Peltier, D., Wolf, S. M., & Connor Barrie, B. T. (2014). Assessing the integrated

effects of landscape fragmentation on plants and plant communities: The challenge ofmultiprocess-multiresponse dynamics. Journal of Ecology, 102(4), 882–895.https://doi.org/10.1111/1365-2745.12223

Ogden, J., Wardle, G. M., & Ahmed, M. (1987). Population dynamics of the emergent conifer Agathisaustralis (D. Don) Lindl. (Kauri) in New Zealand II. Seedling population sizes and gap-phaseregeneration. New Zealand Journal of Botany, 25(2), 231–242.https://doi.org/10.1080/0028825X.1987.10410069

Pawson, S. M., Ecroyd, C. E., Seaton, R., Shaw, W. B., & Brockerhoff, E. G. (2010). New Zealand’s exoticplantation forests as habitats for threatened indigenous species. New Zealand Journal of Ecology,34(3), 342–355.

Rose, A. (2012). Introduction to vegetation monitoring. Wellington.Ryder, J. M., Waipara, N. W., & Burns, B. R. (2016). What is the host range of Phytophthora agathidicida

in New Zealand? New Zealand Plant Protection. University of Auckland.Scott, P., & Williams, N. (2014). Phytophthora diseases in New Zealand forests. NZ Journal of Forestry,

59(2), 14–21.Singers, N. J. D., Osborne, B., Lovegrove, T., Jamieson, A., Boow, J., Sawyer, J., … Webb, C. (2017).

Indigenous terrestrial and wetland ecosystems of Auckland. Auckland.Singers, N. J. D., & Rogers, G. M. (2014). A classification of New Zealand’s terrestrial ecosystems.

Science for Conservation 325. Wellington, N.Z. Retrieved fromhttp://www.doc.govt.nz/documents/science-and-technical/sfc325entire.pdf

Singh, J., Curran-Cournane, F., Waipara, N., Schwendenmann, L., & Lear, G. (2017). Comparison ofmethods used to detect the organism responsible for kauri dieback, Phytophthora agathidicida,from soil samples.

Young, A., & Mitchell, N. (1994). Microclimate and vegetation edge effects in a fragmented podocarp-broadleaf forest in New Zealand. Biological Conservation, 67(1), 63–72.https://doi.org/10.1016/0006-3207(94)90010-8

P O Box 2828, Shortland Street, Auckland 1140. Telephone: (09) 379-9417 Facsimile (09) 307-6409Website: www.bioresearches.co.nz

APPENDIX I – PTA ACTION SHEET

Earthworks Assessment Report Auckland Transport

Project number: 60586377

Prepared for: Auckland Transport AECOM26

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