REPORT Ports of Auckland Assessment of Sediment Quality and Biosecurity for Dumping of Dredged Sediment from the Port of Auckland at the Cuvier Dump Site Submitted to: Ports of Auckland Limited PO Box 1281, Auckland 1140 Submitted by: Golder Associates (NZ) Limited Part 3 of 4 PO Box 33-849, Takapuna 0740, Auckland Appendices E to H +64 9 486 8068 1779496-002-R-Rev0 November 2018 November 2018 1779496-002-R-Rev0 APPENDIX E Review of Alternatives to Disposal at Sea REPORT Disposal of Sediment from the Port of Auckland Assessment of Alternative Methods of Disposal or Management Submitted to: Ports of Auckland Limited PO Box 1281, Auckland 1140 Submitted by: Golder Associates (NZ) Limited Level 1, 214 Durham Street Christchurch 8011 New Zealand +64 3 377 5696 1779496-004-R-Rev0 November 2018 November 2018 1779496-004-R-Rev0 Record of Issue Company Version Date Issued Review Status / Detail Ports of Auckland RevA 23 November 2018 Draft for comment Limited Ports of Auckland Rev0 23 November 2018 Final version Limited ii November 2018 1779496-004-R-Rev0 Table of Contents 1.0 INTRODUCTION ......................................................................................................................................... 1 1.1 Purpose ............................................................................................................................................. 1 1.2 Background ....................................................................................................................................... 1 1.3 Disposal of Dredged Material Within the EEZ ................................................................................... 2 1.4 Beneficial Versus Non-beneficial Uses ............................................................................................. 2 1.5 The 1994 DOAG Outputs .................................................................................................................. 3 2.0 HARBOUR EDGE DISPOSAL ................................................................................................................... 4 2.1 DOAG Outcomes .............................................................................................................................. 4 2.2 Harbour Edge Disposal Update ........................................................................................................ 5 2.2.1 Reclamation .................................................................................................................................. 5 2.2.2 Beach Nourishment....................................................................................................................... 5 2.2.3 Ecological Benefit (habitat creation and restoration) .................................................................... 6 2.2.4 Climate change beneficial harbour edge uses .............................................................................. 7 3.0 LAND DISPOSAL ....................................................................................................................................... 8 3.1 Disposal Options Advisory Group Outcomes .................................................................................... 8 3.2 Land Disposal Update ....................................................................................................................... 8 3.2.1 Landfill ........................................................................................................................................... 8 3.2.2 Landscape reconstruction ............................................................................................................. 9 3.2.3 Soil reuse (manufactured soil) ...................................................................................................... 9 3.2.4 Recreational and amenity uses ................................................................................................... 13 3.2.5 Agriculture and forestry ............................................................................................................... 13 3.2.6 Commercial uses (roading concrete, bricks etc.) ........................................................................ 13 3.2.7 Climate Change .......................................................................................................................... 15 3.3 Treatment to Improve Sediment Quality ......................................................................................... 15 4.0 MARITIME DISPOSAL ............................................................................................................................. 16 4.1 DOAG Outcomes ............................................................................................................................ 16 4.2 Maritime Disposal Update ............................................................................................................... 16 4.2.1 National ....................................................................................................................................... 16 4.2.2 Auckland ..................................................................................................................................... 16 iii November 2018 1779496-004-R-Rev0 5.0 ECONOMICS ............................................................................................................................................ 17 6.0 OVERVIEW OF ALTERNATIVES ............................................................................................................ 17 6.1 Introduction ...................................................................................................................................... 17 6.2 Harbour Edge Disposal ................................................................................................................... 18 6.3 Land Disposal.................................................................................................................................. 18 6.4 Summary ......................................................................................................................................... 18 7.0 REFERENCES .......................................................................................................................................... 19 TABLES Table 1: Beneficial use – Examples of institutional reports. ................................................................................. 2 Table 2: Soil uses – contaminant limits. ............................................................................................................. 10 FIGURES Figure 1: Hierarchy for prioritising dredged material management (Harrington & Smith 2013). .......................... 4 iv November 2018 1779496-004-R-Rev0 1.0 INTRODUCTION 1.1 Purpose Ports of Auckland Limited (POAL) is applying to the Environmental Protection Agency (EPA) for a permit authorising the dumping of dredged material from the Port of Auckland (the Port). The dredged material proposed to be dumped would consist of maintenance and capital dredging material. POAL is applying for a permit to dump the dredged material to the designated offshore disposal site located east of Cuvier Island. This report provides an assessment of alternative methods for the disposal and management of sediment proposed to be dredged from the Port and disposed at the Auckland disposal site, located east of Cuvier Island (referred to as the Cuvier Disposal Site (CDS)). The CDS is one of five authorised locations for marine dumping listed in the Dumping and Discharge Regulations 2015. This report has been prepared by Golder Associates (NZ) Limited (Golder) for Ports of Auckland Limited. It has been prepared to satisfy the matters required to be considered in any impact assessment under Regulation 36 of the Environmental Effects – Discharge and Dumping Regulations (2015). As such, this report: Provides a description of the alternative methods that could be used for disposal. Provides a description of the opportunities to reuse, recycle, or treat the dredged material. This report has been prepared as a supporting appendix to an environmental impact assessment (Golder 2018) for the disposal at the designated CDS. 1.2 Background Dredging is required in the Waitemata Harbour to maintain navigable depths in the approaches to and within the Port of Auckland (the Port, POA). Dredging has been carried out in the Port and navigation channel since the Port was first developed. In 1994, following the disposal of dredged material to a new shallow water disposal site in the Hauraki Gulf, a working group undertook an evaluation of the available options for the management of dredged material in the Auckland region. The Dredging Options Advisory Group (DOAG) produced a series of reports on dredged material disposal options (DOAG 1994a-e) and these are discussed in this report. Subsequently the Hauraki Gulf Marine Park Act 2000 (HGMPA) was introduced to provide integrated environmental management across the Gulf. The HGMPA covers the marine area out to the 12 mile limit west of Great Barrier and Cuvier Island south to the Alderman Islands. The Auckland Regional Policy Statement provides reference to the outcomes of DOAG as they relate to disposal of dredged materials and contaminated material. Since the 1994 DOAG assessment, dredged material within the Auckland region has also been disposed using side-casting (e.g., Pine Harbour marina), to reclamation, to landfill and to sea (outside the 12 mile