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REPORT NO. 2447

SEDIMENT CHARACTERISATION FOR 2013 MAINTENANCE DREDGING OF LYTTELTON INNER HARBOUR

CAWTHRON INSTITUTE | REPORT NO. 2447 JANUARY 2014

SEDIMENT CHARACTERISATION FOR 2013 MAINTENANCE DREDGING OF LYTTELTON INNER HARBOUR

ROSS SNEDDON

Prepared for Lyttelton Port of Christchurch Ltd.

CAWTHRON INSTITUTE 98 Halifax Street East, Nelson 7010 | Private Bag 2, Nelson 7042 | New Zealand Ph. +64 3 548 2319 | Fax. +64 3 546 9464 www.cawthron.org.nz

REVIEWED BY: Paul Barter

APPROVED FOR RELEASE BY: Rowan Strickland

ISSUE DATE: 29 January 2014

RECOMMENDED CITATION: Sneddon R. 2013. Sediment characterisation for 2013 maintenance dredging of Lyttelton Inner Harbour. Prepared for Lyttelton Port of Christchurch Ltd. Cawthron Report No. 2447. 12 p. plus appendices.

© COPYRIGHT: Apart from any fair dealing for the purpose of study, research, criticism, or review, as permitted under the Copyright Act, this publication must not be reproduced in whole or in part without the written permission of the Copyright Holder, who, unless other authorship is cited in the text or acknowledgements, is the commissioner of the report.


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1. INTRODUCTION

1.1. Background

As part of the maintenance dredging programme for Lyttelton Port, sections of the Lyttelton Inner Harbour are dredged to maintain suitable depths for access to berths. Although the Port’s maintenance dredging is effectively an annual programme, the partially enclosed nature of the Inner Harbour means that siltation rates are lower than the main Port approaches in the outer Harbour and dredging is required less frequently. In 2013, Lyttelton Port of Christchurch (LPC) identified the need for dredging of the No.3 west (No. 3 W) berth pocket and a section of the swing basin offshore from the No.2 to No.7 wharves in the Inner Harbour. In order to characterise the sediments to be dredged in terms of their contaminant status, Cawthron Institute (Cawthron) was contracted to implement pre-dredging benthic sampling and a sediment analysis plan (SAP).

1.2. Inner Harbour dredging plan

The two areas of the Inner Harbour dredged in November 2013 are shown in Figure 1. Dredging of both the No.3 W berth pocket and the swing basin area was implemented to achieve a design depth of 11.8 m, yielding projected spoil volumes of 4,101.5 m3 and 44,410 m3, respectively. Based on respective areas of 41,330 m2 and 5,680 m2, nominal depths of cut for the No.3 W berth pocket and swing basin components were 1.1 m and 0.7 m.

1.3. Scope and timing of sampling

The two Inner Harbour dredging areas were considered as distinct blocks for the generation of a sampling schedule. Sample numbers were consistent with the recommendations of the New Zealand Guidelines for Sea Disposal of Waste (MSA/MfE 1999). Due to the short time frames available, only the sampling could be carried out prior to the dredging campaign and some of the information requirements of a comprehensive SAP have been omitted. As part of a separate initiative to upgrade a section of Cashin Quay wharf, outside the Inner Harbour, two sediment samples were also collected along the wharf frontage and characterised as for the SAP samples. Sample collection was conducted on 30 October 2013 using the Canterbury University vessel Rapaki.

JANUARY 2014 REPORT NO. 2447 | CAWTHRON INSTITUTE

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Figure 1. Composite image showing the two principle areas to be dredged (red-shaded within dashed lines) with the sampling plan and sample locations overlaid on an aerial photograph of Lyttelton Inner Harbour. Sample station coordinates in Appendix 1.

2. METHODS

2.1. Sampling plan

No.3 W berth pocket

Due to close proximity to potential contaminant sources (vessels, structures, run-off from land) a higher sampling density is justified for berth pocket areas. It was the intention to collect three sediment samples along the centre-line of the berth pocket but occupation of the berth by two vessels meant that sampling effort was constrained to two samples collected 16 m apart near the mid-point of the berth (Figure 1). Inner Harbour swing basin

In consideration of the projected volume of dredge spoil, the number of samples from the swing basin area was based upon Table 1, Part 2 of the New Zealand Sea Disposal Guidelines (MSA/MfE 1999):

Four samples required for the first 15,000 m3

Two additional samples (pro rata) for the remaining 29,409 m3.


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The swing basin dredging area was divided into six polygons of similar size and sample locations were generated randomly within each (Figure 1). Cashin Quay

Two sediment samples were collected along the earthquake-damaged section of Cashin Quay 2 approximately 5 m out from the wharf front (Figure 2). These were collected incidentally to the Inner Harbour (SAP) samples and are reported here for convenience only.

Figure 2. Sample locations along Cashin Quay 2 wharf frontage. Sample station location coordinates in Appendix 1.

2.2. Sampling methodology

Sediment samples were collected on 30 October 2013 using a 0.1 m2 stainless steel van Veen grab deployed from the University of Canterbury vessel Rapaki. At each station, after confirming the integrity of the sample1, the contents of the grab were sub-sampled with four replicate 60 mm diameter Perspex™ corers driven into the undisturbed grab sediments to a depth of 150 mm. The cores were photographed to provide a visual record of the sediment profile (see Appendix 2). The cores were sub-sampled longitudinally so that analysis results would represent sediments over the full depth of the profile and composited to provide a single sample

1 In soft sediments, the van Veen sampler can collect a relatively undisturbed sample of the seabed substrate to a

depth of 160 mm. The integrity of the sample can be confirmed from complete grab closure and the presence of benthic micro-algal mats and other biogenic features of the sediment surface.


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from each station. The remainder of the cores were also composited to provide sample material for follow-up analyses if required. All sample material was stored on ice for transportation back to the laboratory and then at 4ºC until required for analysis.

2.3. Sediment analyses

The eight composite samples were analysed for trace metals, organotin compounds, semi-volatile organic compounds (SVOCs), polychlorinated biphenyls (PCBs), total petroleum hydrocarbons (TPH), nutrients and total organic carbon (TOC). A summary of the analytes and methods is presented in Table 1.

Table 1. Laboratory methods used for sediment analysis. All analyses carried out by R J Hill Laboratories Ltd (IANZ accredited).

Analyte Method Number Description

Total recoverable digestion

US EPA 200.2. Nitric / hydrochloric acid digestion.

Trace metals (total recoverable Cr, Cu, Hg, Pb, Zn)

US EPA 200.2 Dried sample, sieved as specified (if required). Nitric/Hydrochloric acid digestion. Detected by ICP-MS, trace level.

Total organic carbon (TOC)

Hill Lab in-house method Acid pre-treatment to remove carbonates if present, neutralisation, elementar combustion analyser.

TotalnNitrogen (TN) Hill Lab in-house method Catalytic combustion (900°C, O2), separation, thermal conductivity detector [elementar analyser].

Total recoverable phosphorous (TP)

USEPA 2002 Nitric / hydrochloric acid digestion, Analysis by ICP-MS (inductively coupled plasma mass spectromentry), screen level.

Organotin compounds

Hill Lab in-house method Solvent extraction, ethylation, SPE clean-up, GC-MS SIM analysis. Tested on dried sample

Semivolatile organic compounds (SVOC)

Hill Lab in-house method Sonication extraction, GPC clean-up, GC-MS FS analysis. Tested on as received sample

Polychlorinated Biphenyls (PCB)

Hill Lab in-house method Sonication extraction, SPE clean-up, GPC clean-up (if required), GC-MS analysis. Tested on dried sample

Total petroleum hydrocarbons (TPH)

US EPA 8015B/MfE Petroleum Industry Guidelines.

Sonication extraction in DCM, Silica clean-up, GC-FID analysis Tested on as received sample

2.4. Data analysis and assessment

The consideration of separate berth pocket and swing basin areas, for purposes of sampling and reporting, was based on an expectation that a difference in sediment


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contamination status should exist, arising from usage factors and proximity to sources. However, the relatively small amount of spoil generated by routine maintenance dredging of the Inner Harbour and its subsequent deposition and mixing within a dispersive spoil ground, allows the practical consideration of these areas as essentially one zone. To establish contaminant concentrations for bulk dredge spoil from an Inner Harbour dredging campaign, it is necessary to generate appropriate mean values from the sample results. This requires the application of weighting factors based on relative spoil volumes from each sampled area. In this regard, MSA/MfE (1999) makes specific reference to the use of the geometric (rather than arithmetic) mean for comparison against contaminant screening levels2. For the current investigation, weightings were based on projected spoil volumes from the berth pocket and swing basin spoil representing 8.5% and 91.5% of the total, respectively. These percentages were then divided by the number of samples collected from each area to establish weightings for individual samples (Table 2).

Table 2. Derivation of weighting factors to estimate bulk spoil concentrations from the Inner Harbour component of the 2013 Port Lyttelton maintenance dredging campaign.

No.3 W berth

pocketSwing basin

Total

Dredging volumes (m3) 4,101.5 44,410 48,511.5

Area weighting factor 0.085 0.915 1.00

No. of samples 2 6 8

Sample weighting factor 0.042 0.153

2 It is not unusual for sediment contaminant data to be log-normally distributed, in which case, the geometric

rather than arithmetic mean of a sample series is most appropriate for comparison to sediment quality criteria.


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3. RESULTS AND DISCUSSION

All samples were comprised of fine soft mud. Grain size analysis was not carried out; however, historical results from investigations of benthic conditions at these sites indicate that substrates are predominantly in the silt/clay fraction (<63 µm) with very little coarser material. Photographs of the core samples are presented in Appendix 2. Colour variation down the sediment profile was a noted feature, with grey/brown sediments overlying darker anoxic material. Depth to the apparent redox potential discontinuity3 (aRPD) varied 6–10 cm in the swing basin samples but was less regular in berth pocket samples, consistent with greater physical disturbance from vessels. The analytical results for all samples are listed in Table 3, Table 4 and Table 5.

3.1. Inner Harbour samples

A slight spatial gradient in sediment concentrations of copper, mercury and PAHs was apparent in the six samples collected from across the swing basin area, decreasing west to east (Table 3 and Table 5). It should be noted that, while the New Zealand Sea Disposal Guidelines (MSA/MfE 1999) pre-date the ANZECC (2000) guidelines, the screening levels used for assessment of sediments by MSA/MfE (1999) are effectively identical to ANZECC’s ISQG-Low trigger values and hence the two sets of criteria can be used interchangeably. Trace metals, nutrients and organic enrichment

Although generally elevated above background concentrations, trace metals were at relatively low levels in the samples. Only mercury approached the ANZECC (2000) ISQG-Low criterion, marginally exceeding this trigger for the two No.3 W berth pocket samples (Table 3). Nutrients (total nitrogen and phosphorous) and organic enrichment (TOC) were similarly constrained to quite narrow ranges in the samples and values were not atypical of fine estuarine sediments from elsewhere in New Zealand. Neither ANZECC (2000) nor MSA/MfE (1999) list guideline criteria for these enrichment parameters. Organotin compounds

Tributyltin (Tbt) was above the analytical detection limit in four of the eight samples, exceeding the low trigger value in three samples from the swing basin area. That these exceedances occurred in the swing basin rather than the berth pocket samples was inconsistent with the general expectation of contamination status of the two areas but underscores the high variability typical of this contaminant in port areas.

3 The apparent redox potential discontinuity (aRPD) refers to the often distinct colour change, between surface

and underlying sediments, brought about by the changing redox environment with depth in the profile. This gradient of colour change is in reality continuous but may be reduced to an average transition point (sediment depth) for descriptive purposes.


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Table 3. Elemental sediment constituents. All concentrations expressed on a dry weight basis. Units of mg/kg unless otherwise stated. Trace metals as total recoverable fraction. Values exceeding ANZECC (2000) ISQG-Low presented in bold font.

No.3 W berth Swing basin Cashin Quay ANZECC (2000)

BP01 BP02 SB01 SB02 SB03 SB04 SB05 SB06 CQ2A CQ2B ISQG-L ISQG-H

Chromium 24 25 24 24 24 24 25 24 24 24 80 370

Copper 29 30 22 20 18.4 21 19.1 17.5 12.2 13.3 65 270

Lead 26 27 23 24 22 24 23 23 22 23 50 220

Mercury 0.155 0.157 0.121 0.119 0.101 0.113 0.095 0.093 0.078 0.066 0.15 1

Zinc 94 99 83 85 84 81 85 80 77 80 200 410

Total recoverable phosphorus 970 1,010 940 880 860 830 910 840 950 860 - -

Total nitrogen (g/100g) 0.12 0.13 0.11 0.09 0.1 0.09 0.1 0.1 0.11 0.11 - -

Total organic carbon (g/100g) 1.18 1.17 1.04 0.92 1.04 0.96 1.01 0.91 1.2 1.16 - -

Table 4. Organotin compounds in sediment samples. All concentrations expressed on a dry weight basis. Units of mg/kg. Values exceeding ANZECC (2000) ISQG-Low presented in bold font. Values below analytical detection limit (ADL) in grey-shaded cells.

BP01 BP02 SB01 SB02 SB03 SB04 SB05 SB06 CQ2A CQ2B ISQG-L ISQG-H

Monobutyltin (as Sn) < 0.007 < 0.007 < 0.007 < 0.007 < 0.007 < 0.007 < 0.007 < 0.007 < 0.007 < 0.007

Dibutyltin (as Sn) < 0.005 < 0.005 < 0.005 0.005 < 0.005 0.008 < 0.005 < 0.005 < 0.005 < 0.005

Tributyltin (as Sn) < 0.004 0.003 < 0.004 0.011 < 0.004 0.049 < 0.004 0.008 < 0.004 < 0.004 0.005 0.07

Triphenyltin (as Sn) < 0.003 < 0.003 < 0.003 < 0.003 < 0.003 < 0.003 < 0.003 < 0.003 < 0.003 < 0.003


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Table 5. Semi-volatile organic compounds in sediment samples. All concentrations expressed on a dry weight basis. Units of mg/kg normalised to 1% organic carbon. Values exceeding ANZECC (2000) ISQG-Low presented in bold font. Values below analytical detection limit (ADL) in grey-shaded cells. Summation values for PAHs calculated by substituting non-detects with ADL/2 normalised to organic carbon.

BP01 BP02 SB01 SB02 SB03 SB04 SB05 SB06 CQ2A CQ2B ISQG-L ISQG-H Polycyclic aromatic hydrocarbons

Naphthalene a,b < 0.11 < 0.11 < 0.10 < 0.10 < 0.10 < 0.10 < 0.10 < 0.10 < 0.10 < 0.10 0.16 2.1

2-Methylnaphthalene a < 0.11 < 0.11 < 0.10 < 0.10 < 0.10 < 0.10 < 0.10 < 0.10 < 0.10 < 0.10 0.070 c 0.67 c

Acenaphthylene a,b < 0.11 0.103 < 0.10 < 0.10 < 0.10 < 0.10 < 0.10 < 0.10 < 0.10 < 0.10 0.044 0.64

Acenaphthene a,b < 0.11 < 0.11 < 0.10 < 0.10 < 0.10 < 0.10 < 0.10 < 0.10 < 0.10 < 0.10 0.016 0.5

2-Chloronaphthalene < 0.11 < 0.11 < 0.10 < 0.10 < 0.10 < 0.10 < 0.10 < 0.10 < 0.10 < 0.10 - -

Fluorene a,b < 0.11 < 0.11 < 0.10 < 0.10 < 0.10 < 0.10 < 0.10 < 0.10 < 0.10 < 0.10 0.019 0.54

Anthracene a,b 0.127 0.188 < 0.10 < 0.10 < 0.10 < 0.10 < 0.10 < 0.10 < 0.10 < 0.10 0.085 1.1

Phenanthrene a,b 0.364 0.453 0.144 0.185 0.106 0.125 0.109 < 0.10 0.108 0.103 0.24 1.5

Total low-MW PAHs 0.72 0.93 0.43 0.51 0.39 0.44 0.41 0.38 0.36 0.36 0.552 3.160

Pyrene a,b 0.771 0.923 0.298 0.533 0.212 0.198 0.188 0.187 0.150 0.138 0.665 2.6

Fluoranthene a,b 0.771 0.940 0.298 0.533 0.212 0.177 0.188 0.165 0.158 0.129 0.60 5.1

Benzo[a]anthracene a,b 0.407 0.470 0.144 0.250 0.106 0.104 < 0.10 < 0.10 < 0.10 < 0.10 0.261 1.6

Chrysene a,b 0.331 0.410 0.125 0.239 < 0.10 < 0.10 < 0.10 < 0.10 < 0.10 < 0.10 0.384 2.8

Benzo[a]pyrene (BAP) a,b 0.508 0.598 < 0.2 0.326 < 0.2 < 0.19 < 0.2 < 0.19 < 0.2 < 0.2 0.43 1.6

Benzo[b]- + benzo[j]fluoranthene b 0.508 0.598 0.192 0.326 < 0.2 < 0.19 < 0.2 < 0.19 < 0.2 < 0.2 - -

Benzo[k]fluoranthene b 0.169 0.256 < 0.2 < 0.2 < 0.2 < 0.19 < 0.2 < 0.19 < 0.2 < 0.2 - -

Indeno(1,2,3-c,d)pyrene b 0.254 0.342 < 0.2 < 0.2 < 0.2 < 0.19 < 0.2 < 0.19 < 0.2 < 0.2 - -

Benzo[g,h,i]perylene b 0.339 0.427 < 0.2 0.326 < 0.2 < 0.19 < 0.2 < 0.19 < 0.2 < 0.2 - -

Dibenzo[a,h]anthracene a,b < 0.3 < 0.3 < 0.2 < 0.2 < 0.2 < 0.19 < 0.2 < 0.19 < 0.2 < 0.2 0.063 0.26

Total high-MW PAHs 2.92 3.47 1.06 1.99 0.77 0.73 0.67 0.67 0.56 0.53 1.70 9.60

Total PAHs 3.64 4.40 1.49 2.50 1.16 1.17 1.08 1.05 0.92 0.89 4.00 45.00

Other SVOCs

Bis(2-ethylhexyl)phthalate < 0.9 < 0.9 < 0.8 4.13 < 0.8 < 0.8 < 0.8 < 0.8 < 0.8 < 0.8

a. PAH contributing to summation of low molecular weight (MW), high MW and total PAH values in accordance with ANZECC (2000) Table 3.5.1. b. Included in USEPA list of 16 priority PAH contaminants. c. Guideline levels for 2-Methylnaphthalene provided in MSA/MfE (1999) in the form of ER-L and ER-M from ANZECC (1998).


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A recent review of the ANZECC (2000) sediment quality criteria (Simpson et al. 2008) has recommended an increase in the ISQG-Low value for Tbt to 9 µg Sn/kg (normalised to 1% organic carbon) based on improved effects data, sediment/water partition coefficients and guideline derivation approaches. This recommendation has been adopted as a screening value by the Australian National Assessment Guidelines for Dredging (DEWHA 2009) as part of a phase II (characterisation) assessment. Semi-volatile organic compounds

Semi-volatile organic compounds (SVOCs) were below detectable levels for all classes except for polycyclic aromatic hydrocarbons (PAHs) and a single plasticiser [Bis(2-ethylhexyl)phthalate] in one sample from the swing basin (SB02). PAHs were detected in all samples and exceeded the corresponding ISQG-Low trigger value (where available) within berth pocket samples for seven of the 18 PAH analytes. Individual PAH analytes were below ISQG-Low criteria (where available) for all six swing basin samples, although the trigger value for total high-MW PAHs was exceeded for SB02. Results for the full suite of over 70 SVOCs are listed in Appendix 3. Consideration of exceedances for individual PAH analytes is problematic due to a number of factors, including the absence from relevant guidelines [ANZECC (2000), MSA/MfE (1999)] of trigger values for five of the 18 compounds and detection limits which for six of the 18 exceeded the listed triggers. The list of priority PAHs varies in different countries. In the United States, the EPA (Environmental Protection Agency) has listed 16 priority PAHs, all of which were analysed for in the Lyttelton Inner Harbour samples (Table 5). ANZECC (2000) states that its guideline values for low-MW, high-MW and total PAHs apply to summations comprised of acenaphthene, acenaphthalene, anthracene, fluorene, 2-methylnaphthalene, naphthalene and phenanthrene (for low molecular weight PAHs); and benzo(a)anthracene, benzo(a)pyrene, chrysene, dibenzo(a,h)anthracene, fluoranthene and pyrene (for high-MW PAHs). The ANZECC guidelines have been followed for generation of the totals listed in Table 5, with half the analytical detection limit (ADL/2) substituted where any individual compound was below detectable levels. It should be noted though that ADL/2 exceeded the screening value for three low- and one high-MW PAHs. Simpson et al. (2008) have recommended that trigger values (TV or SQG-Low) for individual PAHs be removed because, “for the majority of assessments, the concentration of total PAHs represents contributions from a large number of individual PAHs, with each being a small percentage of the total” (Simpson et al. 2008). It was also considered unlikely that an individual PAH would, by itself, either dominate the total PAHs concentration or the chemistry line of evidence within toxicity assessments based on a weight of evidence framework. It was furthermore recommended that the trigger value and SQG-high values be set respectively at 10 mg/kg and 50 mg/kg for


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total PAHs4, normalised to 1% organic carbon. As for Tbt, the Australian National Assessment Guidelines for Dredging (DEWHA 2009) have adopted these recommendations for PAHs. Total petroleum hydrocarbons

No petroleum hydrocarbons were above detection in the samples analysed; however the analytical detection limit for total petroleum hydrocarbons (TPH) ranged 80–100 mg/kg (Appendix 3). While no sediment trigger value is listed for petroleum hydrocarbons in either ANZECC (2000) or MSA/MfE (1999), a recommendation of 275 mg/kg for TPH was made by Simpson et al. (2008) and 550 mg/kg was adopted by DEWHA (2009). Polychlorinated biphenyls

Polychlorinated biphenyls (PCBs) were also consistently below detection in all samples; however the detection limit at trace level of 40 µg/kg for total PCBs (35 individual congeners, Appendix 3) exceeded the trigger level of 23 µg/kg listed in MSA/MfE (1999), ANZECC (2000) and (DEWHA 2009). This ADL also exceeded the updated trigger value of 34 µg/kg recommended by Simpson et al. (2008). While there may be potential to apply ultra-trace analytical methods (if available) to sediment samples in future, the absence in this case of detectable levels of any PCB congeners in all samples gives some confidence that these compounds are not present at levels of ecological concern.

3.2. Assessment against screening criteria

The weighted geometric mean values for the target contaminants and parameters are listed in Table 6, along with means for the two individual dredging areas for comparison. While trigger levels were not exceeded by the weighted geometric mean for any analyte, values for low- and high-MW PAHs and Tbt were either at (in the case of Tbt) or not far below the ISQG-Low criteria. An important factor in these higher estimates for the bulk spoil concentration was the high values of analytical detection limit (ADL) relative to the corresponding trigger level, leading to non-detects contributing significantly to the final mean value. This effectively makes the final value more conservative. Although this situation may be avoided by requiring analysis at ultra-trace level, the extra expense may not be justified for all analytes in a first-tier approach. The range and spatial patterns in Tbt values also suggest that the result for the swing basin sample SB04 (0.049 mg/kg, Table 3) may be an outlier resulting from paint flake material. Although the value did not in this case result in exceedance of the screening criterion by the weighted geometric mean, re-analysis (in triplicate) of the sample residual material may have served to validate its status in this regard.

4 Where total PAHs = the sum of the 16 individual non-alkylated PAHs.


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Table 6. Geometric means (as mg/kg dry weight) of contaminants in Inner Harbour benthic sediment samples. Values above ISQG-Low in bold font.

No.3 W

berth Swing basin

Inner Harbour

(weighted) ISQG-Low

Trace metals Chromium 24.5 24.2 24.2 80 Copper 29.5 19.6 20.3 65 Lead 26.5 23.2 23.4 50 Zinc 96.5 83.0 84.0 200 Mercury 0.156 0.106 0.110 0.15

Polycyclic aromatic hydrocarbons

Total low-MW PAHs 0.869 0.477 0.502 0.552

Total high-MW PAHs 4.618 1.371 1.519 1.70

Total PAHs 5.487 1.861 2.039 4.00

Tributyltin (as Sn) 0.002 0.006 0.005 0.005 Nutrients Total recoverable phosphorus 990 876 885 - Total nitrogen (g/100g) 0.125 0.098 0.100 -

3.3. Cashin Quay samples

Analytical results from the two samples collected from the berth at Cashin Quay 2 indicated no exceedances of ANZECC (2000) trigger levels (Table 3, Table 4 and Table 5). Target metal contaminants were at generally lower concentrations than for any of the Inner Harbour samples and enrichment parameters (TOC, TN and TP) were not atypical of undisturbed harbour environments. Organotin compounds, non-PAH SVOCs, PCBs and petroleum hydrocarbons were below analytical detection limits (Appendix 3). The PAHs phenanthrene, pyrene and fluoranthene were detected at low levels (less than ISQG-Low) in both samples.


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4. CONCLUSIONS

Based upon the approach used, the results are considered to meet the guideline criteria for sea disposal of waste outlined within MSA/MfE (1999). The marginality of compliance with screening criteria for Tbt and PAH analytes was exacerbated by relatively high analytical detection limits for these contaminants. Consideration should be given to applying ultra-trace methods (if available) for future monitoring. Since the publication of the New Zealand Sea Disposal Guidelines (MSA/MfE 1999) and ANZECC (2000), there have been relevant new developments in knowledge of the toxicology of contaminated sediments and updated recommendations for sediment quality criteria. These should be taken into account when assessing the suitability for sea disposal of Inner Harbour dredge spoil. Analytical results for the two Cashin Quay samples suggest that sediments dredged from the toe of the batter slope during any reconstruction work would not represent a significant source of contaminants to the Harbour spoil grounds.

5. REFERENCES

ANZECC 1998. Interim Ocean Disposal Guidelines. Australian and New Zealand Environment and Conservation Council. December 1998

ANZECC 2000. Australian and New Zealand guidelines for fresh and marine water quality 2000 Volume 1. National Water Quality Management Strategy Paper No. 4. Australian and New Zealand Environment and Conservation Council and Agriculture and Resource Management Council of Australia and New Zealand, Canberra.

DEWHA 2009. National Assessment Guidelines for Dredging, Department of the Environment, Water, Heritage and the Arts. Commonwealth of Australia, Canberra, 2009.

MSA/MfE 1999. New Zealand Guidelines for Sea Disposal of Waste. Advisory Circular

Part 180: Dumping of Waste or Other Matter Issue No. 180‐1, 30 June 1999. Jointly prepared by the Maritime Safety Authority of New Zealand and the Ministry for the Environment.

Simpson SL, Batley GE, Chariton AA. 2008. Revision of the ANZECC/ARMCANZ Sediment Quality Guidelines. CSIRO Land and Water Science Report 08/07. August, 2008. Revised July, 2010. Prepared for the Department of the Environment, Water, Heritage and the Arts. Australia.


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6. APPENDICES

Appendix 1. Details for benthic stations sampled 30 October 2013.

Station NZ map grid coordinates Water

depth (m) Time

(NZDT) NZMG-E NZMG-N

SAP stations

SB01 2487041 5733452 11.1 10:16

SB02 2487057 5733359 12.0 11:00

SB03 2487202 5733407 11.3 11:22

SB04 2487134 5733354 12.5 11:47

SB05 2487302 5733344 12.0 12:12

SB06 2487238 5733333 12.3 12:32

BP01 2487356 5733513 12.8 12:52

BP02 2487366 5733526 12.7 13:13

Cashin Quay

CQ2-A 2488113 5733114 14.8 13:42

CQ2-B 2487963 5733090 14.6 14:05


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Appendix 2. Photographs of core samples collected from individual grabs 30 October 2013.


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Appendix 3. Full analytical results for sediment polychlorinated biphenyls (PCBs), semi-volatile organic compounds (SVOCs), and petroleum hydrocarbons. All concentrations expressed on a dry weight basis. Units of mg/kg dry weight. Values below analytical detection limit (ADL) in grey-shaded cells.

BP01 BP02 SB01 SB02 SB03 SB04 SB05 SB06 CQ2A CQ2B

Polychlorinated biphenyls

PCB-18 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010

PCB-28 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010

PCB-31 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010

PCB-44 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010

PCB-49 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010

PCB-52 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010

PCB-60 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010

PCB-77 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010

PCB-81 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010

PCB-86 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010

PCB-101 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010

PCB-105 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010

PCB-110 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010

PCB-114 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010

PCB-118 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010

PCB-121 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010

PCB-123 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010

PCB-126 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010

PCB-128 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010

PCB-138 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010

PCB-141 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010

PCB-149 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010

PCB-151 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010


17


PCB-153 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010

PCB-156 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010

PCB-157 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010

PCB-159 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010

PCB-167 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010

PCB-169 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010

PCB-170 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010

PCB-180 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010

PCB-189 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010

PCB-194 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010

PCB-206 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010

PCB-209 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010 < 0.0010

Total PCB (Sum of 35 congeners) < 0.04 < 0.04 < 0.04 < 0.04 < 0.04 < 0.04 < 0.04 < 0.04 < 0.04 < 0.04

Haloethers

Bis(2-chloroethoxy) methane < 0.3 < 0.3 < 0.2 < 0.2 < 0.2 < 0.19 < 0.2 < 0.19 < 0.2 < 0.2

Bis(2-chloroethyl)ether < 0.3 < 0.3 < 0.2 < 0.2 < 0.2 < 0.19 < 0.2 < 0.19 < 0.2 < 0.2

Bis(2-chloroisopropyl)ether < 0.3 < 0.3 < 0.2 < 0.2 < 0.2 < 0.19 < 0.2 < 0.19 < 0.2 < 0.2

4-Bromophenyl phenyl ether < 0.3 < 0.3 < 0.2 < 0.2 < 0.2 < 0.19 < 0.2 < 0.19 < 0.2 < 0.2

4-Chlorophenyl phenyl ether < 0.3 < 0.3 < 0.2 < 0.2 < 0.2 < 0.19 < 0.2 < 0.19 < 0.2 < 0.2

Nitrogen containing compounds

3,3'-Dichlorobenzidine < 1.1 < 1.1 < 1.0 < 1.0 < 1.0 < 1.0 < 1.0 < 1.0 < 1.0 < 1.0

2,4-Dinitrotoluene < 0.5 < 0.5 < 0.4 < 0.4 < 0.4 < 0.4 < 0.4 < 0.4 < 0.4 < 0.4

2,6-Dinitrotoluene < 0.5 < 0.5 < 0.4 < 0.4 < 0.4 < 0.4 < 0.4 < 0.4 < 0.4 < 0.4

Nitrobenzene < 0.3 < 0.3 < 0.2 < 0.2 < 0.2 < 0.19 < 0.2 < 0.19 < 0.2 < 0.2

N-Nitrosodi-n-propylamine < 0.5 < 0.5 < 0.4 < 0.4 < 0.4 < 0.4 < 0.4 < 0.4 < 0.4 < 0.4

N-Nitrosodiphenylamine < 0.5 < 0.5 < 0.4 < 0.4 < 0.4 < 0.4 < 0.4 < 0.4 < 0.4 < 0.4

Organochlorine pesticides

Aldrin < 0.3 < 0.3 < 0.2 < 0.2 < 0.2 < 0.19 < 0.2 < 0.19 < 0.2 < 0.2


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alpha-BHC < 0.3 < 0.3 < 0.2 < 0.2 < 0.2 < 0.19 < 0.2 < 0.19 < 0.2 < 0.2

beta-BHC < 0.3 < 0.3 < 0.2 < 0.2 < 0.2 < 0.19 < 0.2 < 0.19 < 0.2 < 0.2

delta-BHC < 0.3 < 0.3 < 0.2 < 0.2 < 0.2 < 0.19 < 0.2 < 0.19 < 0.2 < 0.2

gamma-BHC (Lindane) < 0.3 < 0.3 < 0.2 < 0.2 < 0.2 < 0.19 < 0.2 < 0.19 < 0.2 < 0.2

4,4'-DDD < 0.3 < 0.3 < 0.2 < 0.2 < 0.2 < 0.19 < 0.2 < 0.19 < 0.2 < 0.2

4,4'-DDE < 0.3 < 0.3 < 0.2 < 0.2 < 0.2 < 0.19 < 0.2 < 0.19 < 0.2 < 0.2

4,4'-DDT < 0.5 < 0.5 < 0.4 < 0.4 < 0.4 < 0.4 < 0.4 < 0.4 < 0.4 < 0.4

Dieldrin < 0.3 < 0.3 < 0.2 < 0.2 < 0.2 < 0.19 < 0.2 < 0.19 < 0.2 < 0.2

Endosulfan I < 0.5 < 0.5 < 0.4 < 0.4 < 0.4 < 0.4 < 0.4 < 0.4 < 0.4 < 0.4

Endosulfan II < 0.5 < 0.5 < 0.5 < 0.5 < 0.5 < 0.5 < 0.5 < 0.5 < 0.5 < 0.5

Endosulfan sulphate < 0.5 < 0.5 < 0.4 < 0.4 < 0.4 < 0.4 < 0.4 < 0.4 < 0.4 < 0.4

Endrin < 0.5 < 0.5 < 0.4 < 0.4 < 0.4 < 0.4 < 0.4 < 0.4 < 0.4 < 0.4

Endrin ketone < 0.5 < 0.5 < 0.4 < 0.4 < 0.4 < 0.4 < 0.4 < 0.4 < 0.4 < 0.4

Heptachlor < 0.3 < 0.3 < 0.2 < 0.2 < 0.2 < 0.19 < 0.2 < 0.19 < 0.2 < 0.2

Heptachlor epoxide < 0.3 < 0.3 < 0.2 < 0.2 < 0.2 < 0.19 < 0.2 < 0.19 < 0.2 < 0.2

Hexachlorobenzene < 0.3 < 0.3 < 0.2 < 0.2 < 0.2 < 0.19 < 0.2 < 0.19 < 0.2 < 0.2

Polycyclic aromatic hydrocarbons

Acenaphthene < 0.11 < 0.11 < 0.10 < 0.10 < 0.10 < 0.10 < 0.10 < 0.10 < 0.10 < 0.10

Acenaphthylene < 0.11 0.12 < 0.10 < 0.10 < 0.10 < 0.10 < 0.10 < 0.10 < 0.10 < 0.10

Anthracene 0.15 0.22 < 0.10 < 0.10 < 0.10 < 0.10 < 0.10 < 0.10 < 0.10 < 0.10

Benzo[a]anthracene 0.48 0.55 0.15 0.23 0.11 0.1 < 0.10 < 0.10 < 0.10 < 0.10

Benzo[a]pyrene (BAP) 0.6 0.7 < 0.2 0.3 < 0.2 < 0.19 < 0.2 < 0.19 < 0.2 < 0.2

Benzo[b- + benzo[j]fluoranthene 0.6 0.7 0.2 0.3 < 0.2 < 0.19 < 0.2 < 0.19 < 0.2 < 0.2

Benzo[g,h,i]perylene 0.4 0.5 < 0.2 0.3 < 0.2 < 0.19 < 0.2 < 0.19 < 0.2 < 0.2

Benzo[k]fluoranthene 0.2 0.3 < 0.2 < 0.2 < 0.2 < 0.19 < 0.2 < 0.19 < 0.2 < 0.2

2-Chloronaphthalene < 0.11 < 0.11 < 0.10 < 0.10 < 0.10 < 0.10 < 0.10 < 0.10 < 0.10 < 0.10

Chrysene 0.39 0.48 0.13 0.22 < 0.10 < 0.10 < 0.10 < 0.10 < 0.10 < 0.10

Dibenzo[a,h]anthracene < 0.3 < 0.3 < 0.2 < 0.2 < 0.2 < 0.19 < 0.2 < 0.19 < 0.2 < 0.2


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Fluoranthene 0.91 1.1 0.31 0.49 0.22 0.17 0.19 0.15 0.19 0.15

Fluorene < 0.11 < 0.11 < 0.10 < 0.10 < 0.10 < 0.10 < 0.10 < 0.10 < 0.10 < 0.10

Indeno(1,2,3-c,d)pyrene 0.3 0.4 < 0.2 < 0.2 < 0.2 < 0.19 < 0.2 < 0.19 < 0.2 < 0.2

2-Methylnaphthalene < 0.11 < 0.11 < 0.10 < 0.10 < 0.10 < 0.10 < 0.10 < 0.10 < 0.10 < 0.10

Naphthalene < 0.11 < 0.11 < 0.10 < 0.10 < 0.10 < 0.10 < 0.10 < 0.10 < 0.10 < 0.10

Phenanthrene 0.43 0.53 0.15 0.17 0.11 0.12 0.11 < 0.10 0.13 0.12

Pyrene 0.91 1.08 0.31 0.49 0.22 0.19 0.19 0.17 0.18 0.16

Phenols

4-Chloro-3-methylphenol < 0.5 < 0.5 < 0.5 < 0.5 < 0.5 < 0.5 < 0.5 < 0.5 < 0.5 < 0.5

2-Chlorophenol < 0.3 < 0.3 < 0.2 < 0.2 < 0.2 < 0.2 < 0.2 < 0.2 < 0.2 < 0.2

2,4-Dichlorophenol < 0.3 < 0.3 < 0.2 < 0.2 < 0.2 < 0.2 < 0.2 < 0.2 < 0.2 < 0.2

2,4-Dimethylphenol < 0.4 < 0.4 < 0.4 < 0.4 < 0.4 < 0.4 < 0.4 < 0.4 < 0.4 < 0.4 3 & 4-Methylphenol (m- + p-cresol) < 0.5 < 0.5 < 0.4 < 0.4 < 0.4 < 0.4 < 0.4 < 0.4 < 0.4 < 0.4

2-Methylphenol (o-Cresol) < 0.3 < 0.3 < 0.2 < 0.2 < 0.2 < 0.2 < 0.2 < 0.2 < 0.2 < 0.2

2-Nitrophenol < 0.5 < 0.5 < 0.4 < 0.4 < 0.4 < 0.4 < 0.4 < 0.4 < 0.4 < 0.4

Pentachlorophenol (PCP) < 6 < 6 < 6 < 6 < 6 < 6 < 6 < 6 < 6 < 6

Phenol < 0.5 < 0.5 < 0.4 < 0.4 < 0.4 < 0.4 < 0.4 < 0.4 < 0.4 < 0.4

2,4,5-Trichlorophenol < 0.5 < 0.5 < 0.4 < 0.4 < 0.4 < 0.4 < 0.4 < 0.4 < 0.4 < 0.4

2,4,6-Trichlorophenol < 0.5 < 0.5 < 0.4 < 0.4 < 0.4 < 0.4 < 0.4 < 0.4 < 0.4 < 0.4

Plasticisers

Bis(2-ethylhexyl)phthalate < 0.9 < 0.9 < 0.8 3.8 < 0.8 < 0.8 < 0.8 < 0.8 < 0.8 < 0.8

Butylbenzylphthalate < 0.5 < 0.5 < 0.4 < 0.4 < 0.4 < 0.4 < 0.4 < 0.4 < 0.4 < 0.4

Di(2-ethylhexyl)adipate < 0.3 < 0.3 < 0.2 < 0.2 < 0.2 < 0.2 < 0.2 < 0.2 < 0.2 < 0.2

Diethylphthalate < 0.5 < 0.5 < 0.4 < 0.4 < 0.4 < 0.4 < 0.4 < 0.4 < 0.4 < 0.4

Dimethylphthalate < 0.5 < 0.5 < 0.4 < 0.4 < 0.4 < 0.4 < 0.4 < 0.4 < 0.4 < 0.4

Di-n-butylphthalate < 0.5 < 0.5 < 0.4 < 0.4 < 0.4 < 0.4 < 0.4 < 0.4 < 0.4 < 0.4

Di-n-octylphthalate < 0.5 < 0.5 < 0.4 < 0.4 < 0.4 < 0.4 < 0.4 < 0.4 < 0.4 < 0.4


20


Other halogenated compounds

1,2-Dichlorobenzene < 0.5 < 0.5 < 0.4 < 0.4 < 0.4 < 0.4 < 0.4 < 0.4 < 0.4 < 0.4



Hexachlorobutadiene < 0.5 < 0.5 < 0.4 < 0.4 < 0.4 < 0.4 < 0.4 < 0.4 < 0.4 < 0.4

Hexachlorocyclopentadiene < 1.1 < 1.1 < 1.0 < 1.0 < 1.0 < 1.0 < 1.0 < 1.0 < 1.0 < 1.0

Hexachloroethane < 0.5 < 0.5 < 0.4 < 0.4 < 0.4 < 0.4 < 0.4 < 0.4 < 0.4 < 0.4

1,2,4-Trichlorobenzene < 0.3 < 0.3 < 0.2 < 0.2 < 0.2 < 0.19 < 0.2 < 0.19 < 0.2 < 0.2

Other SVOC

Benzyl alcohol < 3 < 3 < 2 < 2 < 2 < 1.9 < 2 < 1.9 < 2 < 2

Carbazole < 0.3 < 0.3 < 0.2 < 0.2 < 0.2 < 0.19 < 0.2 < 0.19 < 0.2 < 0.2

Dibenzofuran < 0.3 < 0.3 < 0.2 < 0.2 < 0.2 < 0.19 < 0.2 < 0.19 < 0.2 < 0.2

Isophorone < 0.3 < 0.3 < 0.2 < 0.2 < 0.2 < 0.19 < 0.2 < 0.19 < 0.2 < 0.2

Total petroleum hydrocarbons

C7–C9 < 14 < 13 < 12 < 12 < 12 < 12 < 12 < 12 < 12 < 12

C10–C14 < 30 < 30 < 30 < 30 < 30 < 30 < 30 < 30 < 30 < 30

C15–C36 < 60 < 60 < 50 < 50 < 50 < 50 < 50 < 50 < 50 < 50

Total hydrocarbons (C7–C36) < 100 < 90 < 90 < 90 < 90 < 80 < 90 < 80 < 90 < 90

Documents

CawRpt 2447 Sediment Characterisation for 2013 …...from land) a higher sampling density is justified for berth pocket areas. It was the ... Hill Lab in-house method Solvent extraction,