APPENDIX W SEDIMENT SAMPLING AND ANALYSIS PLAN
Transcript of APPENDIX W SEDIMENT SAMPLING AND ANALYSIS PLAN
Ashburton Infrastructure Project | s.38 Referral Supporting Document
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ISSUE DATE: 25/ 10/ 2021
APPENDIX W SEDIMENT SAMPLING AND ANALYSIS PLAN
Independent Peer Review
Client Mineral Resources Limited
Author O2 Marine
Title Ashburton Infrastructure Project: Sediment Sampling and Analysis Plan
Version Rev 0
Report Date 02/01/21
Reviewer Dr Bruce Hegge, Teal Solutions Pty Ltd
Review Date 19/08/21
Section Review Comment Response Close
Acronyms and Abbreviations
Check to ensure all entries in table shown in text as well as all acronyms/abbreviations in text included in table. Ensure all acronyms and abbreviations are defined when first used in the text
Checked abbreviations mentioned in report match table and are defined in text
1.4 Objectives Include DEC (2009) reference in Section 1.3 1.3. Regulations and Guidelines and include in Section 6 References
Added reference to DEHWA, 2009
2.1 Proposed Dredging
Please provide more details. Will disposal of the dredge material occur to one or more of PPA’s existing offshore disposal sites? How will the preferred disposal site(s) be determined? What is the status of negotiations with PPA regarding this access?
Added disposal will be at one of the designated PPA disposal locations that has not been determined or specified yet.
Figure 2 Would be good to show bathymetry on this figure to provide relevant context for the proposed dredge area
Bathymetry not available at this time
3.1 Site Identification, History and Use
How do the proposed nearshore loading facilities located to the east of the existing Port of Ashburton MOF interface with the proposed AIP Port Marine Facilities?
Expanded information in Introduction to hopefully cover this off
3.2 (Preliminary) Sediment Quality
This section needs a more comprehensive introduction. At present it only notes that it is a reproduction of material from O2M (2020). Note also that O2M (2020) is not included in the references. What is the context for this preliminary work? The discussion of sediment types and historical sediment sampling is confusing and seems to jump between descriptions of marine and onshore sediments. Figure(s) showing the location/concentration of the previous sampling would greatly assist. Not clear why the separation between previous sediment sampling results and sediment sampling undertake to support dredging activity; suggest bring together to describe sediments in the area (e.g. remove the Comments column from Table 3.2 and include a summary in the text
Changed reference to URS 2009b as is where information was actually from. Removed references to soil etc and aligned sediments Removed comments section and summarised prior to table
Section Review Comment Response Close
Table 3.2 Summary of historical sediment sampling
This is a good table but would be better retitled as it relates to previous dredging campaigns and may be better as section on its own e.g. ‘Dredging history’. Also Expand table to include details on proponent, volume of sediment dredged, reference(s) for the sediment sampling results, disposal site used, information on dredging approvals granted (e.g. permit). Include figure to show location of the dredging and disposal sites.
Added information that was available as recommended. Added figure showing locations of sites done in 2019 as example
4.1 Contaminants of Potential Concern
Rewrite this section to provide clearer justification for the selection of the contaminants of concern.
Amended section to justify selection of COPC from previous sampling
Section 4.1.1 to Section 4.1.5
Move these all to second level heading under 4 Sampling Design. Ensure clear and logical flow of information, e.g. suggest move Section “Sampling Techniques” to be above “Sampling Sites and Depths” so that pushcore and vibrocore are defined prior to first reference
Moved suggested sections
4.1.1 Sampling design and rational
This section here should be moved to the top of Section 4 Sampling Design and merged with the text there. Expand text to justify the classification of the material as ‘probably clean’
Moved and expanded on the justification
4.3.1 Comparison of Data to Screening Levels
Provide more clarity and details on the proposed method of normalisation of analytes
Taken as written in NAGD, referenced the table where normalisation method is located in document
4.3 Data Analysis and 4.4 Data Analysis
Why two headings with same title? Combine the content of these two sections for better flow and clarity (e.g. at present discussion on the calculation of the 95% UCL occurs in two places) To improve clarity please include a table showing for each analyte the: proposed Limits of Reporting; laboratory analytic method; guideline/trigger values, and source of guideline/trigger value
Combined and added table for metals showing details etc
6 References Check references to ensure all references in text include here and conversely no references here that are not in text
Checked the references
CLIENT: Mineral Resources Limited
STATUS: Rev 1 REPORT No.: R200270
ISSUE DATE: 23/09/2021
Ashburton Infrastructure Project Sediment Sampling and Analysis Plan
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dealing for the purposes of private study, research, criticism or review as permitted under the Copyright
Act 1968, no part may be reproduced, copied, transmitted in any form or by any means (electronic,
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O2 Marine waives all responsibility for loss or damage where the accuracy and effectiveness of
information provided by the Client or other third parties was inaccurate or not up to date and was relied
upon, wholly or in part in reporting.
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Acronyms and Abbreviations
Acronyms/Abbreviation Description
0C Degrees Celsius
ABA Acid-Base Accounting
ADAS Australian Diver Accreditation Scheme
AIP Ashburton Infrastructure Project
Ag Silver
ANC Acid Neutralisation Capacity
ANCBT Acid Neutralisation Capacity (by back titration)
Al Aluminium
As Arsenic
ASS Acid Sulphate Soils
AS/NZS Australian Standard / New Zealand Standard
BTEX Benzene, Toluene, Ethylbenzene and Xylene
Cd Cadmium
cm Centimetre
CoC Chain of Custody
COPC Contaminant of Potential Concern
Cu Copper
DBT Dibutyltin Tributyltin
DE Development Envelope
DER Department of Environmental Regulations
DGV Default Guideline Value
DSO Direct Shipping Ore
EIA Environmental Impact Assessment
EIL Ecological Investigation Levels
EP Environmental Protection
EPP Eastern Planning Precinct
Fe Iron
FF Fineness Factor
g Grams
GPS Global Positioning System
Hg Mercury
HIL Health Investigation Levels
HSE Health, Safety and Environment
ID Identification
ISQG-Low Interim Sediment Quality Guideline Low level
ISQG-High Interim Sediment Quality Guideline High level
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Acronyms/Abbreviation Description
ISO International Standards Organisation
JSEA Job Safety and Environmental Analysis
km Kilometres
L Litres
LAT Lowest Astronomical Tide
m Metres
m2 Square metres
m3 Cubic metres
MBT Monobutyltin
Mg Magnesium
mg/kg Milligrams per kilogram
MOF Materials Offloading Facility
Mn Manganese
MS Ministerial Statement
Mtpa Millions of Tonnes Per Annum
NAGD National Assessment Guidelines for Dredging 2009
OGV Ocean Going Vessel
SNAS Net Acid Soluble Sulfur
NATA National Association of Testing Authorities
Ni Nickel
PAH Polycyclic Aromatic Hydrocarbons
PASS Potential Acid Sulfate Soils
Pb Lead
PC Push Corer
pHF Screening Acidity
pHFOX Oxidised Screening Acidity
PPA Pilbara Ports Authority
PQL Practical Quantitative Limits
PSD Particle Size Distribution
RPD Relative Percent Difference
RSD Relative Standard Deviation
SAP Sample and Analysis Plan
SCR Reduced Inorganic Sulfur
SQG Sediment Quality Guidelines
TAAKCl Titratable Actual Acidity
TBT Tributyltin
TOC Total Organic Carbon
TRH Total Recoverable Hydrocarbons
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Acronyms/Abbreviation Description
TSVs Transhipment Vessels
TTA Total Titratable Acid
UCL Upper Confidence Limit
µg/L Micrograms per Litre
V Vanadium
QA/QC Quality Assurance and Quality Control
Zn Zinc
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Contents
1. Introduction 9
Description of the Proposed Ashburton Project 9
Marine Elements of the Proposed Project 9
Scope 12
Regulations and Guidelines 12
Objectives 12
2. Project Description 14
Proposed Dredging 14
3. Background 15
Site Identification, History and Use 15
Preliminary Sediment Quality 15
Dredging History 16
4. Sampling Design 20
Contaminants of Potential Concern 21
Sampling Techniques 22
QA/QC 26
Data Analysis 27
5. Reporting 31
6. References 32
Figures
Figure 1. Project area and development envelopes. 11
Figure 3. Spatial extent of proposed dredge area 14
Figure 4. Map of dredged area and previous sampling sites from 2019. 17
Figure 5. a) Diver operated push corer b) Vibrocorer 22
Figure 6. Proposed Sediment Sampling Locations 23
Tables
Table 3-1 Summary of results of previous dredging campaigns 18
Table 4-1 Proposed sediment sampling samples 24
Table 3. Reporting guidelines for metals. 27
Table 4-3 Reaction observations to determine appropriate rating 28
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1. Introduction
Description of the Proposed Ashburton Project
MRL is undertaking planning for iron ore mining and export developments in the West Pilbara region of WA. The proposed Ashburton Infrastructure Project (AIP) involves a fully sealed private road, commencing at the boundary of the approved Buckland mine (Bungaroo South mine) (MS906 and MS1147), about 45 km southwest of Pannawonica, and continuing for about 150 km westward to a new port landside handling and storage facilities at the Port of Ashburton (the Port). Export is proposed from port landside and marine export facilities within the Port, including a dedicated nearshore berth facility and offshore anchorages. The AIP will initially support the export of approximately 30 million tonnes of iron ore per annum (Mtpa) through the Port over a 10-year period as a Direct Shipping Ore (DSO), with future plans to support the export of 40 Mtpa over a 30 to 40-year period from approved future mine developments.
The Port was established by Chevron for the Wheatstone Liquified Natural Gas Project (Wheatstone) about 12 km southwest of Onslow. In 2020, a change in the nominated proponent from Chevron to Pilbara Ports Authority (PPA) was approved for the shipping channel, Materials Offloading Facility (MOF), and access road. Through consultation with PPA, MRL understands that a Section 45C application under the Environmental Protection (EP) Act to amend Ministerial Statement (MS) 1131 to include the Eastern Planning Precinct and allow for final elevations to be achieved is currently under preparation. MRL are planning on entering a commercial control with PPA (via the submission of Development and Construction Applications), whereby, MRL enter into a lease agreement with PPA, allowing the AIP to be developed and for MRL to carry out activities on PPA vested lands, seabed or water areas.
The AIP will utilise proposed and existing marine facilities to load ore onto Transhipping Vessels (TSVs) that will travel along PPA’s dredged shipping channel, out to deep water (up to 40 m water depth), to five dedicated anchorage points located about 10 km from Thevenard Island. Ore will be loaded from TSV’s onto Capesize, Ocean Going Vessels (OGV) at a maximum of two of the five anchorage points at any one time.
Marine Elements of the Proposed Project
The AIP Port Marine elements will be located within the existing Port and includes three main Development Envelopes (DEs): Port Landside (Landside), Port Nearshore (Nearshore) and Port
Offshore (Offshore) (Figure 1).
Landside DE: located within the Eastern Planning Precinct (EPP), of the PPA’s landside planning area. No new disturbance is proposed within this DE. Landside facilities include a storage of bulk handling of iron ore, a seawater desalination plant, power station bulk storage of fuel, administration building, a sewerage treatment facility and a seawater desalination plant at the Port.
Nearshore DE: The Marine Nearshore infrastructure, includes a dedicated berthing pocket, a modular jetty wharf and ship loader and will be constructed in Port Waters managed by the PPA east of the existing MOF. The modular wharf has been designed to be a fixed-point loading wharf, with roadway access and lifting areas for up to 130 t cranes. The jetty and wharf structure includes provision for seawater intake and outfall pipelines.
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A temporary causeway (rock structure) is required for the construction of the approach jetty and will be removed once jetty construction has been completed. Construction from a temporary causeway versus overhand construction will reduce the number of piles required and also, also reducing the duration of proposed piling. This will reduce the impacts to sensitive marine fauna. Piling for the temporary causeway will involve the installation of twenty 1,000 mm drive piles.
The new berth and jetty will require a dredging programme and offshore disposal of dredge material at PPA’s existing Spoil Ground C (see Figure 1). Capital dredging of approximately 150,000 m3 to modify the existing access channel for the MOF to allow safe access and berthing of TSVs at the nearshore wharf facility. Capital dredging will be undertaken to achieve a depth of -4 m lowest astronomical tide (LAT), with the proposed dredge footprint extending approximately 30,000 m2. The location of the jetty has been selected to enable transhipment barges to sail into port under ballast draft (3.5 m maximum draft) without any tidal constraints and moor at the berth.
Offshore DE: Includes the offshore anchorage points for transfer of ore from TSVs to Cape size Ocean
Going Vessels (OGV). The TSV navigation route traverses between the Offshore and Nearshore DEs.
This report focusses on the following construction components of the Nearshore and Offshore DE
shown in Figure 1:
capital dredging of a berth pocket and the construction of a dedicated wharf for loading of
Transhipment Vessels (TSVs) located immediately east of the existing Port of Ashburton
Materials Offloading Facility (MOF),
marine disposal locations for dredge material removed from the berthing pocket
the transhipment area in ~30-50 m water depth approximately 10 km to the west/north-west of
Thevenard Island for anchorage of Cape Size vessels.
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Figure 1. Project area and development envelopes.
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Scope
MRL engaged O2 Marine (O2M) to undertake a quality assessment of the contamination status of the
sediments located within the AIP’s capital dredging footprint and to identify the source of potential
contamination, should it exist.
This document outlines the Sampling and Analysis Plan (SAP) for baseline assessment and
characterisation of sediments associated with the proposed dredging. The outcome of this SAP will
enable a determination of the contaminant status of the material and suitability for offshore disposal as
well as provide input on sediment characteristics for dredge plume modelling.
Regulations and Guidelines
This document has been prepared with consideration of the following guidelines:
Department of the Environment, Water, Heritage and the Arts (DEHWA): National Assessment
Guidelines for Dredging, Commonwealth of Australia, Canberra 2009, (DEHWA, 2009).
The Department of Environment Regulation (DER): Identification and Investigation of Acid
Sulfate Soils and Acidic Landscapes, June 2015 (DER 2015).
The National Assessment Guidelines for Dredging (NAGD), 2009 (NAGD 2009); and
ANZG 2018. Australian and New Zealand Guidelines for Fresh and Marine Water Quality.
Australian and New Zealand Governments and Australian state and territory governments,
Canberra ACT, Australia. Available at www.waterquality.gov.au/anz-guidelines
Objectives
Sediment investigations are required to adequately characterise the level of contamination and potential
acid sulfate soils (PASS) in the proposed dredge sediments to ensure potential impacts of dredged
material loading and disposal are adequately assessed and managed responsibly and effectively.
The regulatory framework for assessment of sediments to be dredged and proposed for ocean disposal
is outlined in NAGD (2009). The methodology for assessment of PASS is outlined in the Identification
and Investigation of Acid Sulfate Soil and Acidic Landscape (DEC 2015). The findings of this
investigation will support preparation of an Environmental Impact Assessment (EIA) and regulatory
environmental approvals for the AIP.
Specific objectives of the sediment sampling program are:
To determine the suitability of the dredged sediment for offshore disposal1;
To identify the risk to marine environmental quality resulting from disturbance and mobilisation
of the sediments; and
1 The project is proposing to place the dredging material at Spoil Ground C (Figure 1) which is an
existing designated offshore disposal site managed by Pilbara Port Authority (PPA).
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To adopt an analytical program for sediment characterisation in accordance with relevant
guidelines applicable to the management and assessment of dredged sediments.
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2. Project Description
Proposed Dredging
Dredging will be undertaken over approximately 30,000 m2 located immediately to the East of the
existing Port of Ashburton MOF (Figure 2). Capital dredging of approximately 150,000 m3 will be
required at the nearshore wharf site to a depth of -4 m LAT to allow safe access and berthing of TSVs.
Dredge material is proposed to be disposed at the existing designated offshore disposal site C,
managed by PPA, pending relevant environmental approvals (Figure 1).
Figure 2. Spatial extent of proposed dredge area
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3. Background
Site Identification, History and Use
The Port of Ashburton is located to the east of the Ashburton River mouth and approximately 12 km
south-west of the town of Onslow in the Pilbara region of Western Australia, within the Shire of
Ashburton. Onslow is located approximately 1,400 km north of Perth and 360 km south of Karratha.
The Port of Ashburton was originally constructed to support the development of the Wheatstone LNG
and domestic gas project. Chevron Australia Pty Ltd (Chevron), on behalf of the Wheatstone Joint
Venture partners, is the sole operator of the Wheatstone Marine Terminal at the Port of Ashburton and
enables the export of LNG and other hydrocarbon-based products. Since it commenced operations in
December 2011, management and operation of the Port and a portion of the multi-user infrastructure
corridor has been vested to the PPA. In 2017, PPA was granted a 5-year Sea Dumping Permit
(SD2016/3282) to allow for maintenance dredging of the Port of Ashburton. PPA have implemented
annual sediment sampling in accordance with an approved sampling and analysis plan to monitor and
manage the potential environmental impacts from the maintenance dredging campaigns.
The future development of the Port reflects the State Governments intention on making Ashburton a
hub for hydrocarbon related trade by enabling the export capacity of LNG to approximately 50 million
tonnes per annum. To support this outcome nearshore loading facilities are proposed East of the
existing Port of Ashburton MOF.
Preliminary Sediment Quality
The following sediment quality summary is reproduced from URS, 2009b.
The marine sediments in the region mainly consist of silt and sand sheets of varying thickness overlying
Pleistocene limestone. Near the Ashburton Delta (approximately 9 km East of Port of Ashburton),
sediments are generally fine silts and clays with high silica content (URS, 2009b).
Two broad types of marine sediments occur within the nearshore area: sands intermixed with variable
fractions of clays, silts and or gravels, and rock (siltstone, claystone and sandstone) that is generally
weathered and weak (URS, 2009a). The proportion of the two sediment types changes with increasing
distance from the shore. In the MOF and Product Loading Facility (PLF) basin the assumed material to
be dredged consists of 75% sand and 25% weak rock (URS, 2009a). In the PLF approach channel the
material will be 60% sand and 40% weak rock (URS, 2009a). In both cases, sand is assumed to overlay
the rock. Sediments become increasingly coarse and increase in calcium carbonate content with
distance offshore, due to decreasing input of terrigenous silts and clays from river runoff and coastal
erosion (Coffey, 2009).
The chemical characteristics of marine sediments in the vicinity of the Ashburton North Site has been
assessed on two previous occasions, once in 2005 by the DEC (2006) and by URS in the Wheatstone
dredging area (URS 2009a).
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The DEC (2006) study recorded no discernible anthropogenic enrichment of contaminants (e.g.,
organotins, hydrocarbons, organochlorine pesticides and polychlorinated biphenyls) in sediments
offshore of the Ashburton River mouth. The study also measured natural background concentrations of
trace metals in the marine sediments, noting that with the exception of arsenic, natural background
concentrations of all metals were below the relevant Australia and New Zealand Environment and
Conservation Council/Agricultural and Resource Management Council of Australia and New Zealand
(superseded by ANZG 2018) screening levels (DEC 2006).
During the URS (2009a) survey, marine surface sediments and deep cores were sampled within and
near the proposed dredging area and grab samples from the proposed nearshore disposal grounds.
Analytes tested for were as below:
Metals (aluminium, arsenic, cadmium, chromium, copper, iron, lead, manganese, mercury,
nickel, silver, vanadium, zinc).
Total Petroleum Hydrocarbons,
Xylene (BTEX)
Tributyl tin (TBT)
Total Organic Carbon (TOC)
Particle Size Analysis (PSD).
The study recorded concentrations of all contaminants and trace metals as being below the laboratory
limit-of reporting (LOR) or below the relevant National Assessment Guidelines for Dredging (NAGD)
(Commonwealth of Australia 2009d) screening levels, with the exception of arsenic and nickel which
are naturally occurring (URS 2009a).
The current major pressure on sediment quality in the vicinity of the Project area is from shipping
activity, wastewater discharges from (i.e., Wheatstone and Onslow Salt) and mobilisation of
contaminated sediments through maintenance dredging.
Dredging History
The recent history of dredging (Figure 3) and associated sediment sampling surrounding the Port of
Ashburton demonstrates that the sediments are largely uncontaminated, apart from a small number of
locations inside the MOF that have detected elevated concentrations of nickel and other metals
(Table 3-1). Based on results from previous sampling, sediments from the shipping channel and MOF
have been considered clean and suitable for unconfined ocean disposal.
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Figure 3. Map of dredged area and previous sampling sites from 2019.
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Throughout all the surveys there have been consistent findings in relation to the tested parameters
where there were generally no exceedances of the relevant guidelines for metals, organic hydrocarbons
or nutrients. Nickel was shown to exceed the NAGD screening levels during all the surveys conducted,
however when the bioavailable concentration of nickel was quantified and retrospectively compared,
these concentrations were shown to meet screening guidelines (PPA, 2020). Additionally, manganese
was detected in elevated concentrations for all surveys, however no fixed screening levels have been
attributed to the metal’s toxicity in marine sediment (ANZG, 2018).
Table 3-1 Summary of results of previous dredging campaigns
Proponent, Year
Study Location of Sediment Dredging volume (m3)
Permit
Chevron, 2009 URS (URS, 2009a) Capital dredging channel, turning basin and MOF at the Port of Ashburton.
48,000,000
Pilbara Ports Authority, 2016
MScience (MScience, 2016)
Capital dredging channel, turning basin, MOF and proposed spoil grounds at the Port of Ashburton.
Up to 300, 000
Pilbara Ports Authority, 2017
MScience (MScience, 2017)
Capital dredging channel, turning basin, MOF and proposed spoil grounds at the Port of Ashburton.
Up to 300, 000 SD2016/3282
Pilbara Ports Authority, 2018
MScience (MScience, 2018)
Capital dredging channel, turning basin, MOF and proposed spoil grounds at the Port of Ashburton.
Up to 300, 000 SD2016/3282
Pilbara Ports Authority, 2019
Advisian (Advisian, 2019)
Capital dredging channel, turning basin, MOF and proposed spoil grounds at the Port of Ashburton.
Up to 300, 000 SD2016/3282
Pilbara Ports Authority, 2020
MScience (MScience 2020)
Capital dredging channel, turning basin, MOF and proposed spoil grounds at the Port of Ashburton.
Up to 300, 000 SD2016/3282
Pilbara Ports Authority, 2021
O2 Marine (O2M, 2021)
Berth Pocket for Transhipment vessels
Up to 150, 000
Acid Sulfate Soils
A geochemical assessment of the sediment was undertaken for the Wheatstone Project to determine
whether the potential for acid sulfate soils (PASS) to develop exists (URS, 2009b). The investigation
involved 72 samples collected from 15 deep core borehole locations at varying depths. Analytical
methods used to determine the presence of PASS included the Acid Sulfate Soils Screening test (based
on pHF and pHFOX values and reaction ratings), the Chromium Suite (Scr) for Acid Sulfate Soils test
(based on levels of Scr, pHKCL, total titratable acid (TTA) and acid neutralising capacity (ANC)) and a
targeted Carbonate Buffering assessment (URS, 2009b).
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The pHF values ranged from 7.2 in silty/clayey sands to 8.5 in clayey sandy gravel. Subsequent pHFOX
values ranged from 6.4 to 7.4, indicating the likelihood of encountering PASS is low. Reaction types
ranged from slight to strong throughout the sediment profile with strongest reactions observed in
claystone (URS, 2009b). The Scr results showed only eight (8) of 91 nearshore sampling locations
recorded elevated acid levels slightly above the action criteria trigger value of 0.03% Sulfur. However,
the ANC of sediments generally indicated a potential buffering of low pH sediments (URS 2009b).
Further testing was performed on the carbonate buffering properties of sediments to re-evaluate the
availability of carbonate material for acid neutralisation. The ANC values ranged from 17-
620 kg H2SO4/tonne, with the low ANC levels 17-26 kg H2SO4/tonne only slightly calcareous. However,
the rates of availability for circum-neutral buffering were found to be “chemically non-limiting” and
sediments had sufficient available carbonate buffering capacity to negate any potential acidity in the
event of PASS oxidation (URS (2009b).
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4. Sampling Design
The estimated volume to be dredged for the project is approximately 150,000 m3 over an area of
30,000 m2 (Figure 2). The dredging area have not previously been dredged and may therefore be
classified as a capital dredging campaign. However, the north boundary of the dredging footprint
coincides with the MOF shipping channel boundary which has been previously dredged.
The proposed sampling design was based on the following assumptions:
The proposed capital dredging area has not previously been disturbed and can be classified
as ‘probably clean’ as described in Appendix D of the National Assessment Guideline for
Dredging (NAGD 2009).
Capital dredging campaigns require sampling to the full depth of potentially contaminated
sediment, which for the purpose of this SAP involves at least the top one metre of sediment
(Appendix D, NAGD 2009). As such the number of sample locations was based on the total
area of 30,000 m2 to a depth of one metre equating to a total dredge volume of 30,000 m3.
As described for capital dredging in Appendix D of the National Assessment Guideline for Dredging
(NAGD 2009), the number of sample locations is based on the volume of the layer of recent sediments
which could be contaminated (top 1 m of sediment) but does not include the volume of underlying
natural geological materials which are, except for a thin boundary layer, expected to be
uncontaminated. The number of sample locations, therefore, is based on the volume of contaminated
and potentially contaminated dredged material which is separated into three (3) categories (NAGD,
2009):
Probably contaminated – areas such as inner harbour or berth areas
Suspect – areas such as outer harbours
Probably clean – areas such as shipping channels
Previous sampling results in the area have shown that there were no exceedances of the relevant
guidelines for metals, organic hydrocarbons or nutrients. Therefore, the proposed dredging area for this
capital dredging campaign should be classified as ‘probably clean’ (as described in NAGD 2009).
Utilising these previous results and as this is a capital dredging campaign, the sampling should focus
on the top one metre of sediment (over the area of 30,000 m2) which may be possibly contaminated. In
accordance with NAGD (2009), the number of sampling locations for this volume of ‘probably clean’
sediments is nine (Table 4-1).
For capital dredging projects, where contamination is not suspected, NAGD (2009) does not require
sediment sampling deeper than 1 m below the existing seabed. However, it is proposed to attempt
coring to the full depth of proposed dredging at two (2) locations within the dredge footprint to
characterise the underlying sediments, particularly for presence of PASS.
Sampling to 1 m will be undertaken at seven (7) sampling locations via manual push corer. At each
location, subsamples will be collected from the core at two horizons (top horizon: 0 m to 0.5 m and
bottom horizon: 0.5 m to 1 m). Laboratory analysis will be undertaken from the top horizon for all
locations, whilst samples collected from the bottom horizon will be held by the laboratory, to be analysed
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only if the laboratory results indicate an exceedance of the NAGD (2009) screening levels within the
top horizon.
Sampling to proposed full dredging depth (i.e., -4 m LAT), or refusal will be undertaken at two (2)
random sampling locations within the dredging footprint (Site 8 and 9, Figure 5) to assess the presence
of contaminants of potential concern (COPC) in the deeper sediment layers.
At these locations subsamples will be collected and analysed from the following horizons, or until
refusal:
• 0 m to 0.5 m;
• 0.5 m to 1 m;
• 1 m to 2 m;
• 2 m to 3 m; and
• 3 m to 4 m.
Contaminants of Potential Concern
Based on the history of sediment sampling and existing data within the Port of Ashburton area, the
COPC include the following:
Metals (aluminium, antimony, arsenic, cadmium, chromium, copper, iron, lead, manganese,
mercury, nickel, silver, zinc).
Hydrocarbons, including total recoverable hydrocarbon (TRH), benzene, toluene,
ethylbenzene, xylenes and naphthalene (BTEXN) and polycyclic aromatic hydrocarbon (PAH).
Organotins: tributyl tin (TBT), dibutyl tin (DBT) and monobutyl tin (MBT).
Acid Sulphate Soil2: including both the screening test and chromium suite analysis.
Since 2015, previous sampling campaigns have shown concentrations of nickel and manganese (which
is currently compared to a low reliability guideline) to be above NAGD screening levels, however the
bioavailable concentrations have met screening levels. Therefore, bioavailability testing is
recommended for nickel and manganese to determine whether the bioavailable concentration of these
metals meet the recommended screening guidelines.
TOC has been analysed historically for normalisation of organic constituent results to 1 percent TOC
for comparison to screening levels. PSD is also assessed for normalising metal concentrations to a
reference element (if required) where the grain size and TOC of a compatible reference area for ambient
baseline levels cannot be located.
2 Field PASS testing shall be completed on all samples and chromium suite analysis will only be
undertaken in the event field screening testing indicates PASS.
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Sampling Techniques
Sediment sampling will be undertaken using either vibrocorer or push corer fitted with stainless steel
core catchers to maximise the recovery of the core.
Push Coring
A push corer (Figure 4a) will be used at seven (7) sites to recover cores to a depth of 1 m (or refusal).
The push corer consists of a 70 mm stainless steel core with polycarbonate inner tube that is advanced
manually into the seabed or, if required, using a sleeve hammer. A bung will be inserted in the top of
the corer before extraction from the seabed. Once extracted a cap will be placed on the base and
transported to the surface by the diver in an upright position to avoid disturbance or loss of fine particles.
On return of the cores to the surface the water will be carefully removed, a photographic and observation
record of the core will be taken. For each core, two sub-samples will be collected from each horizon
(i.e. 0 m to 0.5 m and 0.5 m to 1 m) homogenised (with exception of samples collected for volatile
analysis3) and placed into laboratory containers.
a)
Figure 4. a) Diver operated push corer b) Vibrocorer
b)
Vibrocoring
A vibrocorer (Figure 4b) will be used to recover sediments to the refusal depth below the seabed from
two (2) sites. This method allows the bottom conditions to be observed by the diver which can aid in
sample recovery. The vibrocorer is deployed over the side of the vessel and positioned vertically over
3 Samples for volatile analysis, i.e. will be collected from the undisturbed core before homogenizing
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the seabed by the diver. Once in position the diver communicates to topside to activate the unit.
Vibrations are transferred across the stainless-steel barrel which cause a liquefaction of the surrounding
sediment and allow the barrel to penetrate the seabed. The vibrocorer contains a core catcher to further
minimise sample disturbance during collection and retrieval. This sampling method is approved in the
NAGD (2009) and provides rapid and flexible mobilisation to site and efficient collection of samples. If
corer refusal occurs above the proposed sampling depth the core will be sampled to the maximum
possible depth. Once the sample has been taken the corer will be filled with water, capped at the top
and then extracted from the seabed back to the surface. Once the vibrocorer has been retrieved back
to the surface and onto the vessel, the samples will be split into the following horizons before being
homogenised and collected into laboratory specific containers:
• 0 to 0.5 m;
• 0.5 m to 1 m; and
• at 1 m interval for any horizon below 1 m
4.2.1. Sampling sites and depths
Sampling locations were randomly distributed across the dredging footprint as recommended in
NAGD (2009).
Figure 5. Proposed Sediment Sampling Locations
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Table 4-1 Proposed sediment sampling samples
Site Method Sample ID Horizon
1 PC MR-01-TOP 0 m-0.5 m
MR-TRIP-01 0 m-0.5 m
MR-TRIP-02 0 m-0.5 m
MR01-BOT 0.5 m-1 m
2 PC MR02-TOP 0 m-0.5 m
MR02-SPLIT 0.5 m-1 m
MR02-BOT 0.5 m-1 m
3 PC MR03-TOP 0 m-0.5 m
MR03-BOT 0.5 m-1 m
4 VC MR04-TOP 0 m-0.5 m
MR04-0.5-1m 0.5 m-1 m
(and subsequent 1 m intervals to refusal)
5 PC MR05-TOP 0 m-0.5 m
MR05-BOT 0.5 m-1 m
6 PC MR06 TOP 0 m-0.5 m
MR-DUP 0 m-0.5 m
MR06-BOT 0.5 m-1 m
7 PC MR-07-TOP 0 m-0.5 m
MR-07-BOT 0.5 m-1 m
8 VC MR-08 0-0.5m 0 m-0.5 m
MR08 0.5-1m 0.5 m-1 m
(and subsequent 1 m intervals to refusal)
9 PC MR09-TOP 0 m-0.5 m
MR09-BOT 0.5 m -1 m
VC – Vibrocore
PC – Push Core
4.2.2. Field equipment
The following sampling equipment shall be used:
Suitable Vessel;
Tape measure
Dive gear according to ADAS standard
2299.2;
Pony bottles;
Tethers for the divers;
Core trays;
Rinsed sample containers provided by
the laboratory;
Eskies and ice;
Nitrile gloves;
Pyrex glass bowls;
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Oxy-viva and first aid kit;
Vessel dive flag;
Vessel GPS system;
Handheld GPS (back-up);
Vibrocorer (76 mm Ø);
5 x stainless steel core catchers;
Polycarbonate core tubes (50mm x 1.8m
length)
Piston Corer;
Catch bags;
Internal rubber bung and rod to extrude
samples;
Plastic Spoons and bowls;
Decon 90 (or equivalent cleaning agent);
Plastic tubs and brushes for washing;
Waterproof marker pens;
Camera;
Ice blocks for sample transport to the
laboratory;
Chain of Custody forms; and
Field logs
4.2.3. Sampling Procedure
The general sampling procedure will include the following:
The vessel to be used for sampling will be decontaminated before commencement of sampling.
A GPS unit (WGS84) with a minimum five metres of horizontal accuracy will be used to navigate
and record the sampling location. If environmental and safety conditions do not allow site
access, the site will be revisited (where possible) later or the sample site repositioned as close
as possible to the original location, but within a safe distance for operations. GPS locations of
all sampled sites will be recorded.
Prior to obtaining each sample, the sampling equipment, processing equipment and workspace
shall be decontaminated by scrubbing initially with seawater collected on site, second scrub
using Deacon 90, and final rinse with freshwater.
Each sample will be photographed prior to homogenization in the mixing bowl and again
following homogenization. Photographs shall be taken on a white background so both sample
and core sheet plate are captured in the image with information such as sample ID, date, time,
location. Site observations will be recorded including but not limited to benthic/terrestrial habitat,
surface features, observed fauna, etc.
A visual description of each sample will be recorded on the log sheet.
All sample handling shall be undertaken using fresh pair of nitrile gloves and samples will be
homogenised in a glass bowl, except for the samples to be collected for the hydrocarbon
analysis which will be extracted from the middle of the cores and not mixed in accordance with
procedures described in the NAGD (2009). The samples will then be placed directly into labelled
clean containers supplied by the laboratory. For hydrocarbons analyses, sediment will be placed
into the jars with zero headspace to minimise volatilisation.
Samples will be placed in eskies at <4ºC immediately after collection. Chain of Custody (CoC)
documentation shall be completed at the completion of each survey day.
Sampling, handling, transportation, storage, preservation and labelling techniques will be
conducted in accordance with the NAGD (2009), and samples shall be delivered for analysis
sealed, within the recommended holding time and with a temperature recoded at the time of
delivery to the laboratory.
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QA/QC
4.3.1. Field QA/QC
The following QA/QC procedures shall be undertaken during field work in accordance with ANZG (2018)
and NAGD (2009) guidelines, including:
Using suitably qualified environmental staff experienced in sediment sampling, field
supervision and sediment logging;
Survey vessel shall be thoroughly inspected and washed down prior to the survey;
All sampling equipment, including mixing bowls etc. shall be decontaminated between
sampling locations via a decontamination procedure involving a wash with ambient seawater
and a laboratory grade detergent, and successive rinsing with freshwater;
Samples shall be handled using gloved hands (nitrile gloves). New gloves shall be used for
each sample to avoid potential cross-contamination;
Samples shall be contained in appropriately cleaned, pre-treated and labelled sample
containers;
Logs shall be completed for each sample collected including time, location, initials of sampler,
duplicate type, chemical analyses to be performed and site observations;
Chain-of-custody (CoC) forms identifying (for each sample) the sampler, nature of the sample,
collection date and time, analyses to be performed, sample preservation method and
departure time from the site;
Samples shall be kept cool (4°C) after sampling and during transport, stored in eskies with
pre-frozen ice bricks;
Transportation of samples under CoC documentation (Appendix A); and
Additional QC field samples collected in accordance with the NAGD (2009).
4.3.2. Field Quality Control Samples
Field quality control samples included the following sampling design in accordance with Appendix F of
the NAGD (2009):
One (1) trip blank filled with inert chromographic sand. This container will be kept closed for
the whole duration of the survey and transport to the lab and will be analysed for the
contaminants of concern to assess contamination that may occur due to transport procedures.
One (1) field blank filled with inert chromographic sand; This container will be open and kept
on site in proximity of sample processing procedures and will be analysed to assess
contamination that may occur due to environmental conditions and/or processing procedures.
Two (2) rinsate blanks filled with deionised water; at the end of each survey day all equipment
will be decontaminated as per decontamination procedure described in section 4.2.1. After the
decontaminant is completed, the equipment is rinsed with deionised water which will be
collected and analysed to assess the effectiveness of the decontamination procedure.
Two (2) field triplicates (three separate samples taken at the same location) to determine the
variability of the sampling method; and
One (1) field split (samples thoroughly mixed then split into two sub-samples with one of the
samples sent to a secondary laboratory) to assess variability between laboratories methods.
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4.3.3. Laboratory QA/QC
Both the primary and secondary laboratories will be National Association of Testing Authorities (NATA)-
accredited for the relevant analytes and have comprehensive best practice QA/QC programs in
accordance with NEPC (1999), ANZG (2018) and NAGD (2009) guidelines. Laboratory QA/QC includes
Laboratory Control Samples (LCS), Method Blanks (MB), Matrix Spikes (MS), Laboratory Duplicates
(Dups) and Surrogates (where applicable), at frequencies at or above the NEPM guidelines – revised
2013.
Data Analysis
4.4.1. Comparison of Data to Screening Levels
The results shall be compared to the recommended interim sediment quality guidelines (ISQG)
screening levels in the NAGD (2009), and Default Guideline Values (DGVs) as defined in ANZG (2018),
while PASS will be compared against the action criteria in DER (2015). The recommended sediment
quality guidelines (SQGs) for the Pilbara coastal waters shall also be applied for parameters in which
no DGVs are available. Estimated natural background data for manganese is not available in DEC
(2006) and therefore a low reliability guideline value (used as an indicative interim working level) from
The Ontario Ministry of the Environment (Persaud et al. 1990) presented in ANZG (2018) shall be
applied.
In accordance with Table 2 in NAGD (2009), the raw laboratory results for organic analytical parameters
such as hydrocarbons and organotins will be normalised to 1% TOC where TOC values are within the
range 0.2-10%. If TOC is outside this range the end value is used as default (e.g., <0.2% = 0.2% and
>10% =10%).
Based on NAGD (2009), the 95% upper confidence limit (95% UCL) is compared to the ISQG and
DGVs for metal concentrations (Table 2). The USEPA’s ProUCL software is used to calculate and
recommend the most appropriate 95% UCL test to apply based on the data size, data distribution and
skewness. If the 95% UCL does not exceed the screening level, this means there is a 95% probability
that the mean concentration of that contaminant will not exceed the screening level. If the 95% UCL of
a contaminant exceeds the specified screening level, there is risk sediments to be dredged may pose
an ecological risk and further investigation shall proceed through the decision-tree described in NAGD
(2009).
In accordance with the decision-tree in NAGD (2009), in the event the upper 95 per cent confidence
limit of the mean for a contaminant exceeds the ISQG or DGV, comparison to ambient baseline levels
is then required. This can be achieved through comparing the upper 95% UCL against nearshore
sediment sampling results from URS (2009) undertaken prior to development of the Ashburton Port.
The sites will be targeted for comparable grainsize and TOC content, since these parameters are the
dominant influences on contaminant levels in sediment.
Table 2. Reporting guidelines for metals.
Analyte LoR Laboratory
Method
ISQG-low NAGD PQL Trigger Value
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4.4.2. PASS Field Screening Test
The results obtained from three (3) PASS field screening tests described below will be used to identify
sediments likely to contain sulphides:
‘A ‘High’ or greater reaction rating with hydrogen peroxide as classified in Table 4-3
Actual value of pHFOX <6; and
Difference in pHFOX and pHF value of > 2 units.
The field screening tests provide a rapid assessment of the likelihood of PASS although cannot give a
quantitative measure of the amount of PASS in the sediment, or how much will be produced through
oxidation. However, a precautionary approach will be adopted for interpreting the combination of these
three factors to arrive at a positive identification of sulfides or PASS for deciding which samples warrant
further analysis using the Chromium Reducible Sulfur Suite method. This may include further testing of
samples which record a high-risk result of PASS from only a single test, or a moderate risk result of
PASS in more than one test result.
Table 4-3 Reaction observations to determine appropriate rating
Reaction Rating Key Observations
Low L Little to no reaction, languid bubble formation
Medium M Languid bubble formation two or more layers
High H Active bubble formation inside test tube, mild effervescence
Aluminium 50 mg/kg ICP-AES 6300 mg/kg 200 mg/kg 95% UCL
Iron 50 mg/kg ICP-AES 16200 mg/kg 100 mg/kg 95% UCL
Antimony 0.5 mg/kg ICPMS 2 mg/kg 0.5 mg/kg 95% UCL
Arsenic 1 mg/kg ICPMS 20 mg/kg 1 mg/kg 95% UCL
Cadmium 0.1 mg/kg ICPMS 2.5 mg/kg 0.2 mg/kg 95% UCL
Copper 1.0 mg/kg ICPMS 65 mg/kg 1 mg/kg 95% UCL
Cobalt 0.5 mg/kg ICPMS N/A 0.5 mg/kg 95% UCL
Lead 1.0 mg/kg ICPMS 50 mg/kg 1 mg/kg 95% UCL
Manganese 10 mg/kg ICPMS N/A 10 mg/kg 95% UCL
Nickel 1.0 mg/kg ICPMS 21 mg/kg 1 mg/kg 95% UCL
Silver 0.1 mg/kg ICPMS 2 mg/kg 0.1 mg/kg 95% UCL
Zinc 1.0 mg/kg ICPMS 200 mg/kg 1 mg/kg 95% UCL
Mercury 0.01 mg/kg FIMS0.15 0.15 mg/kg 0.01 mg/kg 95% UCL
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Reaction Rating Key Observations
Extreme X Foaming inside test tube, moderate effervescence, faint sulfuric odour
Volcanic V Vigorous foaming & overflow/ eruption, strong effervescence, strong
sulfuric odour
4.4.3. Chromium Reducible Sulfur Suite
This analysis will only be required if a sample fails the ASS Field Screening Test.
The chromium reducible sulfur suite method involves a series of steps that yield an estimate of the
actual and potential acidity, the acid neutralising capacity (ANC) and the total net acidity of a sediment
sample. The soil pH, in potassium chloride suspension (pHKCl), gives an estimate of the actual acidity
of the sediment. The reduced inorganic sulfur content (SCr) provides an estimate of the potential sulfidic
acidity of the sediment, which is assessed against an Action Criteria (DER 2015). Titratable Actual
Acidity (TAAKCl) and/or Net Acid Soluble Sulfur (SNAS) are analysed if pHKCl is <6.5. The ANC provides
an estimate of the ability of the sediment to naturally neutralise any acid produced (e.g., due to the
presence of carbonate material).
The total net acidity is calculated via Acid-Base Accounting (ABA), using the following equation (Ahern
et al. 2004):
Net Acidity = Potential Sulfidic Acidity + Existing Acidity – (ANC ÷ FF)
Where:
Potential Sulfidic Acidity is represented by SCr
(converted from %S to mol H+/tonne by multiplying by 623.7).
If there is no existing acidity, i.e., the sample has a pHKCl greater than 6.5, the TAAKCl is assumed to be
zero and the Existing Acidity term is neglected. If the pHKCl is less than 6.5, the TAAKCl is measured and
used for the Existing Acidity term in mol H+/tonne.
ANC is represented by ANCBT
(converted from %CaCO3 to mol H+/tonne by multiplying by 199.8).
• FF is the fineness factor and
• ANCBT is the Acid-neutralising capacity by back titration. Acid-neutralising capacity measured
by acid digest followed by back titration of the acid that has not been consumed.
As the samples are finely ground in the laboratory, the actual ANC in the field could be overestimated
and therefore the net acid risk, underestimated. To allow for this, the measurements of ANC are divided
by a fineness factor (FF) during ABA. A fineness factor of 1.5 was selected for this study to ensure a
conservative calculation of the neutralising capacity for the fine shell and carbonate silts.
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4.4.4. QA/QC Assessment
The precision of the sediment analyses shall be determined by quantifying the differences between the
concentrations of analytes in the QA/QC samples, using the method outlined in NAGD (2009).
The relative percent difference (RPD) shall be calculated for analyte concentrations in the sample splits
(both inter-laboratory and intra-laboratory splits) and field replicates as follows:
RPD (%) = (𝑑𝑖𝑓𝑓𝑒𝑟𝑒𝑛𝑐𝑒 𝑏𝑒𝑡𝑤𝑒𝑒𝑛 𝑠𝑎𝑚𝑝𝑙𝑒 𝑠𝑝𝑙𝑖𝑡𝑠) 𝑋 100
(𝑎𝑣𝑒𝑟𝑎𝑔𝑒 𝑜𝑓 𝑠𝑎𝑚𝑝𝑙𝑒 𝑠𝑝𝑙𝑖𝑡𝑠)
The RPD of sample splits should be less than ±35% for field splits and ±50% for field replicates,
although the guidelines note that this may not always be the case where the sediments are very
heterogeneous or greatly differing in grain size and/or in very low concentration (NAGD 2009). Where
three (3) or more samples were collected from the one location (e.g., triplicate) the relative standard
deviation (RSD) shall be calculated for analyte concentrations in the sample splits. If the RPD for a
measured analyte fell outside of these limits, the value of the measured analyte shall be flagged as an
estimate rather than a precise value (NAGD 2009).
The RSD shall be calculated as follows:
(𝑠𝑡𝑎𝑛𝑑𝑎𝑟𝑑 𝑑𝑒𝑣𝑖𝑎𝑡𝑖𝑜𝑛 𝑜𝑓 𝑠𝑎𝑚𝑝𝑙𝑒𝑠)
(𝑎𝑣𝑒𝑟𝑎𝑔𝑒 𝑜𝑓 𝑠𝑎𝑚𝑝𝑙𝑒𝑠)
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5. Reporting
A sediment sampling and analysis implementation report shall be prepared and shall include the
following content:
• Introduction
• Methods
o Sampling and Analysis Procedures
o Figures and accompanying table showing the sampling locations and coordinates
respectively.
• Results
o Colour graphical representations of results with the ANZG (2018) (a) DGV and DGV-
High (where available) superimposed on the graph.
o Tabulated analytical results highlighting exceedances of (a) Screening and (b)
Maximum Levels.
o Data Validation – comparison of analytical data against the Data Quality Criteria
identified for the SAP and confirming compliance with QA/QC procedures and
confirmation that the data is suitable for the purpose for which it has been collected.
• QA/QC
o Field QA/QC Procedures
o Laboratory QA/QC Procedures
• Conclusion
o Provide discussion and explanation of results if exceedances occur
• References
• Appendices:
o Site and sample photographs
o Laboratory reports including QA/QC
o Chain of Custody
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6. References
Advisian (2019). Port of Ashburton Maintenance Dredging ASAP Implementation Report (Year 3 – 2019). Report for PPA. ANZG (2018). Australian and New Zealand Guidelines for Fresh and Marine Water Quality. Australian and New Zealand Governments and Australian state and territory governments, Canberra ACT, Australia. Available at www.waterquality.gov.au/anz-guidelines Coffey (2009). Nearshore Geotechnical Investigation – Downstream. Unpublished report for Chevron Australia Pty. Ltd.
Department of Environment and Conservation (2006). Background quality of the marine sediments of the Pilbara coast. Department of Environment and Conservation, Marine Technical Report Series, No. MTR 1 Department of the Environment, Water, Heritage and the Arts (DEHWA): National Assessment
Guidelines for Dredging, Commonwealth of Australia, Canberra 2009, (DEHWA, 2009)
Department of Environment Regulation (2015). Identification and investigation of acid sulfate soils and acidic landscapes. DER2015001427 Department of Sustainability, Environment, Water, Population and Communities (DSEWPaC) (2009). National Assessment Guidelines for Dredging, Canberra MScience (2016). Port of Ashburton Dredging Program: Sampling and Analysis Plan Implementation Report. Report to PPA. MScience (2017). Port of Ashburton Maintenance Dredging: Annual Sampling and Analysis Plan Implementation Report, 2017. Report to PPA. MScience (2018). Port of Ashburton Maintenance Program: Annual Sampling and Analysis Plan Implementation Report, 2018. Report to PPA. MScience (2020). Port of Ashburton Dredging Program: Annual Sampling and Analysis Plan Implementation Report, 2020. Report to PPA. National Environmental Protection Council (NEPC), (1999). Schedule B of the National Environmental Protection Measures. URS (2009a). Sediment Quality Assessment-Wheatstone Dredging Program, 2009. Report #42907466/00090/01. Technical Appendix Q5 of Environmental Impact Statement Chevron (2010): https://australia.chevron.com/-/media/australia/our-businesses/documents/wheatstone-draft-eis-ermp-technical-appendices-q2-to-q5-web.pdf URS (2009b). Wheatstone Project: Nearshore Acid Sulfate Soils Investigation (Turning Basin & Dredge Channel). Report #42907466/01. Technical Appendix Q4 of Environmental Impact Statement Chevron (2010): https://australia.chevron.com/-/media/australia/our-businesses/documents/wheatstone-draft-eis-ermp-technical-appendices-q2-to-q5-web.pdf
Ashburton Infrastructure Project | s.38 Referral Supporting Document
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ISSUE DATE: 25/ 10/ 2021
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