3.0

Initial Environmental Evaluation Geotechnical Investigations Davis Aerodrome Project (Project 5097) and Davis Station Infrastructure Project (Project 5135) 2021-2022 Field Activities

V3.0 – 30 March 2021 INITIAL ENVIRONMENTAL EVAULATION 2021-2022 FIELD SEASONS

Contents

1 Non-Technical Summary ...... 5 1.1 Introduction ...... 5 1.2 Description of the Proposed Activity ...... 5 1.3 Alternatives to the Proposed Activities ...... 5 1.4 Impact Assessment ...... 5 1.5 Mitigation Measures ...... 6 1.6 Environmental Monitoring and Management ...... 7 1.7 Conclusion ...... 7 2 Introduction and Scope ...... 8 2.1 Introduction ...... 8 2.2 Davis Aerodrome Project Background ...... 8 2.3 Davis Station Infrastructure Project Background ...... 10 2.4 Statutory Requirements ...... 10 2.5 Purpose and Scope of the Document ...... 10 2.6 Previous Assessments and Obligations ...... 11 3 Description of the Proposed Activity ...... 12 3.1 Aims and Objectives ...... 12 3.2 Overview of Proposed Activities ...... 12 3.2.1 2020-21 Summer Program ...... 12 3.2.2 2021 Winter Program ...... 12 3.2.3 2021-22 Summer Program ...... 12 3.3 Location of the Proposed Activity ...... 13 3.4 Nominal Sequence of Season Activities ...... 15 3.5 Site Access and Preparation ...... 15 3.6 Geotechnical Investigations ...... 16 3.6.1 Borehole Drilling ...... 16 3.6.2 Borehole Instrumentation Installation and Monitoring ...... 23 3.6.3 Downhole Instrumentation Quantum ...... 25 3.6.4 Test Pit Excavation ...... 26 3.6.5 Dynamic Cone Penetrometer testing ...... 31 3.6.6 Geological Mapping and Geotechnical Visual Observations ...... 31 3.6.7 Geophysical Survey ...... 32 3.6.8 Near-surface Water Flow Investigations ...... 33 3.6.9 Lake and Waterbody Depth Monitoring ...... 33

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3.7 Surveys ...... 34 3.7.1 Terrestrial Survey ...... 34 3.7.2 Hydrographic Survey ...... 34 3.8 Equipment, Logistics and Methods of Proposed Activities...... 34 3.8.1 Site Access and Preparation ...... 34 3.8.2 Geotechnical Borehole Drilling ...... 35 3.8.3 Supply of Drilling Fluid ...... 36 3.8.4 Downhole Instrumentation Monitoring ...... 36 3.8.5 Temporary Mobile Weather Shelter Provisions ...... 37 3.8.6 Hand-Augered Boreholes...... 37 3.8.7 Test Pit Excavation ...... 38 3.8.8 Dynamic Cone Penetrometer Testing...... 41 3.8.9 Geological Mapping...... 41 3.8.10 Geophysical Survey ...... 42 3.8.11 Re-establishment of Existing and/or New Temporary Access Tracks...... 43 3.8.12 Near-surface Water Flow Monitoring...... 43 3.8.13 Lake and Waterbody Level Monitoring...... 44 3.8.14 Survey ...... 45 3.8.15 Samples Collection ...... 46 4 Alternatives to the Proposed Activity ...... 47 4.1 Do Nothing ...... 47 4.2 Alternate Locations and Timing ...... 47 4.3 Alternate Methods and Technologies ...... 47 5 Description of the Environment...... 48 5.1 Physical Characteristics of the Vestfold Hills ...... 48 5.1.1 Biota ...... 50 5.1.2 Birds...... 50 5.1.3 Seals ...... 51 5.1.4 Terrestrial Microbiota ...... 51 5.1.5 Flora ...... 51 5.1.6 Marine Benthic (Seabed) Biota ...... 51 5.1.7 Meteorology and Climate ...... 52 5.1.8 Human Presence ...... 52 5.1.9 Scientific Values ...... 53 5.1.10 Wilderness and Aesthetic Values ...... 54 5.1.11 Cultural Heritage Values and Historic Importance ...... 54 5.1.12 Location of Main Wildlife Concentrations ...... 55

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6 Impact Assessment and Mitigation Measures ...... 56 6.1 Methods and Data Used in Impact Assessment ...... 56 6.2 Potential Impacts and Mitigation Measures ...... 56 6.2.1 Impacts on Ice and/or Ice-free Areas ...... 56 6.2.2 Introduced Materials Associated with Field Activities ...... 59 6.2.3 Works in Proximity to Lakes and Waterbodies ...... 61 6.2.4 Fuel Spills, Waste Disposal and Loss of Equipment...... 62 6.2.5 Vehicle and Equipment Emissions ...... 63 6.2.6 Native Flora, Fauna and Habitat ...... 64 6.2.7 Cultural Heritage Values and Historic Importance ...... 65 6.2.8 Interface with Other Programs or Projects in the Local Area ...... 65 6.2.9 Cumulative Impacts ...... 66 6.3 Environmental Monitoring and Management ...... 66 7 Conclusion ...... 67 8 Contact details ...... 67 9 References ...... 68 APPENDIX 1 ...... 70 APPENDIX 2 ...... 76

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1 Non-Technical Summary 1.1 Introduction The Australian Antarctic Division (AAD) has undertaken this Initial Environmental Evaluation (IEE) of its proposed 2021-2022 field activities in support of the Davis Aerodrome Project (DAP) (Project 5097) and the Davis Station Infrastructure Project (SIP) (Project 5135), collectively referred to as “the Project” herein. This IEE covers proposed activities to be undertaken throughout the 2020-21 summer, 2021 winter, and 2021-22 summer seasons.

This IEE has been prepared in accordance with the Antarctic Treaty (Environment Protection) Act 1980 (ATEP Act) and the Antarctic Treaty (Environment Protection) (Environment Impact Assessment) Regulations 1993 (EIA Regulations). 1.2 Description of the Proposed Activity The main objectives of the proposed field work associated with the Project, are to continue the collection of critical geotechnical and environmental data to inform ongoing Project design, construction, and delivery efforts, essential for the planning phase for the Project, which includes:

· the engineering design of the proposed Aerodrome at the Ridge Site, located approximately 4km north of Davis Station · the engineering design of the proposed access track, from Davis Station to the Aerodrome · the engineering design and logistical planning of assets to facilitate Project construction · the engineering design of enabling and stabilisation works for the existing Davis Station infrastructure · provide supplementary baseline data, to support future infrastructure planning and the preparation of environmental impact assessments for these activities.

The field program proposed over the 2021-2022 seasons is to nominally comprise a number of components including.

· fieldwork preparation activities · geotechnical borehole drilling and test pit excavation investigations, · the sampling of representative soil, rock, and groundwater · installation of in-situ monitoring instrumentation, to assess temporal variations in ground conditions (temperature, movement, and groundwater levels) · undertake visual geological and geotechnical observations and assessments · terrestrial and hydrographic surveys; and · geophysical surveys. 1.3 Alternatives to the Proposed Activities Investigation of the following alternatives to the proposed activities have been undertaken, and discussed further in Section 4.0

1. Do nothing. 2. Conduct activities at alternate locations or at different times during the season. 3. Use of alternate methods and technologies. 1.4 Impact Assessment Key potential environmental impacts associated with the proposed field works, if unmitigated over the 2021-2022 seasons include:

· Emissions from transportation and motorised equipment will have an impact on air quality. · The potential for minor, localised fuel spills from vehicles and equipment used in the field. MARCH 2021 5 INITIAL ENVIRONMENTAL EVAULATION 2021-2022 FIELD SEASONS

· The proposed fieldworks will result in short term, visible ground disturbance until the sites are remediated upon completion of works. Impacts on microbiota and soil processes cannot be avoided, however these are anticipated to be of a localised scale and deemed short-term. · The proposed borehole drilling process requires lubrication, with seawater nominated and the potential requirement for the use of drilling additives where deemed required. Noting the use of drilling additives, such as calcium chloride and viscosifiers, they are only to be used where necessary, in minimal volumes required to meet project objectives, aligning with the approach of the successfully delivered historical geotechnical drilling programmes from previous field seasons and their use in broader polar environments. The anticipated environmental impacts of the proposed additives are proposed to be localised in scale and deemed short-term.

o Calcium chloride is to be used to increase the salinity of the drilling fluid which in turn will reduce the freezing point of the liquid during drilling. This increase in salinity will prevent the drilling equipment from being frozen within the borehole, leading to potentially adverse operational impacts. Calcium chloride is nominated as opposed to sodium or potassium chlorides due to similar performance effects being realised with a reduced volume of additives applied. The reduced volume of additives proposed, is suggested to minimise potential environmental impacts. o Viscosifiers, are proposed to provide a manageable drilling fluid to reduce the potential for borehole instability and collapse during operations, reducing the potential for water loss to ground formations during drilling, improve the quality of sample recovery. Products proposed for use are highly dispersive, versatile blend of cellulosic and organic polymers which form a high viscosity fluid that exhibits good hole stabilising characteristics in all types of drilling applications. Where possible non-toxic and biodegradable options were selected to further reduce the potential for environmental impacts.

· The combined effect from the noise, vibration and dust from the works will be confined to the immediate vicinity of the work site and associated service vehicles and therefore are anticipated to have minor, short-term impacts on wildlife. 1.5 Mitigation Measures A suite of measures based on past experience and expert advice has been developed to minimise the environmental impacts associated with this field program. All project personnel deployed to deliver the proposed fieldwork program will be required to have undertaken an environmental briefing, based upon this IEE and its related mitigation measures, Environmental Authorisations, Permits, operational conditions and relevant AAD Standard Operating Procedures (SOP’s)1, notably Environmental Management and Protection (Volume 1, Chapter 2). All personnel are to be made aware of their responsibilities as an individual, and collectively and to adhere to the terms of the governing Environment Authorisations and Permits.

The implementation of the following measures by the Project are proposed to mitigate adverse impacts on the environment by:

· Consideration as to logistic requirements and the sequencing of location and type of activities prior to departure, to maximise project efficiency and reduce environmental impacts by performing the minimum required activities to achieve project goals.

1 https://www.antarctica.gov.au/antarctic-operations/field-operations/field-travel-and-fuel-management/

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· Prior to commencement, worksites are to be reviewed, assessed, and selected to avoid environmentally sensitive areas, with preference given to using existing disturbed areas and tracks, where present. · Upon completion of works, where ground has been disturbed, it is proposed to be reinstated to visually resemble pre-works conditions, with photographic records of all pre- and post- works documented. · All equipment and project materials are to be processed and handled by AAD’s Supply Services Group who are to be responsible for ensuring compliance with the Australian Government’s regulations on the export and import of cargo, including scientific samples, to and from the Antarctic and sub-Antarctic, to prevent the introduction of non-native species to the Antarctic environment. · Drilling induced waste is to be managed in accordance with AAD’s Station and Field Waste Management Guide. o Solid human waste bagged and kept frozen and liquid waste stored on site in grey water drums for disposal on station o All non-human solid waste must be returned from the field to station for sorting and eventual recycling or disposal to landfill. The drill cuttings collected as part of the works, where not returned to the borehole upon completion of drilling, are to be disposed of in the form of Landfill waste, with import permits to be obtained from DAWE for materials to be treated as landfill material for disposal in Tasmania. · Waste materials are to be assessed for reuse potential prior to disposal. · Only appropriately qualified, trained and site inducted personnel are to prepare, inspect, maintain, and operate fieldwork equipment and machinery. · The works will be undertaken in accordance with AAD procedures and policies, including “Work Health and Safety”, “Environmental Protection and Management”, “Station Operations” (Volume 1, Chapters 1, 2 and 4), “Aviation Standard Operating Procedures” (Volume 5). Where required, and any supplementary project specific procedure and requirements will be applied. · All works are to be undertaken in accordance with Environmental Authorisations, Permits and Conditions, with an environmental audit framework developed to assist on-site station leadership undertake inspections as required. 1.6 Environmental Monitoring and Management Compliance with the AAD’s Environmental Policy and the mitigation measures detailed in this IEE are the responsibility of all personnel undertaking the proposed activity. The Project’s Field Team Leader and the Proponent of the activity will actively manage and monitor to ensure adherence to the relevant policies, procedure, permits and authorisations, including environmental permits and authorisations. 1.7 Conclusion This IEE concludes that, provided the recommended mitigations are implemented, the proposed 2021-2022 field activities are likely to have no more than a minor or transitory impact on the Antarctic environment.

MARCH 2021 7 INITIAL ENVIRONMENTAL EVAULATION 2021-2022 FIELD SEASONS 2 Introduction and Scope 2.1 Introduction The Australian Antarctic Division (AAD) has undertaken this Initial Environmental Evaluation (IEE) of its proposed field activities in support of the Davis Aerodrome Project (DAP) and the Davis Station Infrastructure Project (SIP), collectively referred to as “the Project” herein. This IEE covers activities being undertaken throughout the 2020-21 summer, 2021 winter, and 2021-22 summer seasons.

This IEE has been prepared in accordance with the Antarctic Treaty (Environment Protection) Act 1980 (ATEP Act) and the Antarctic Treaty (Environment Protection) (Environment Impact Assessment) Regulations 1993 (EIA Regulations). 2.2 Davis Aerodrome Project Background Investigation of year-round aviation access to Antarctica is a key initiative under the Australian Government Australian Antarctic Strategy and 20 Year Action Plan (2016) to support Australia’s ongoing Antarctic leadership.

The Strategy and Action Plan 2commits to scoping options for expanded aviation capabilities to establish a year-round aviation capability between Hobart and Antarctica in accordance with domestic and Antarctic Treaty system environmental approval requirements. The AAD has established the Davis Aerodrome Project to undertake this work.

The AAD has previously undertaken a range of geotechnical and environmental investigations to assist feasibility, site assessment and preferred location of year-round aviation infrastructure development. The key activities undertaken in previous field seasons, are summarised as follows:

· Field Season 2012-13; During the 2012-13 field season long term ground condition monitoring instruments were installed within boreholes at Adams Flat (approximately 4 km northeast of Davis Station) under the Davis Aerodrome Project. Site investigations were undertaken including surface geology mapping; shallow test pit excavation and soil sampling; shallow seismic survey; ecological soil survey and GIS survey. Soil samples for terrestrial ecology studies were collected from four sites in this field season – Adams Flat, Heidemann Valley, Old Wallow and Rookery Lake.

· Field Season 2016-17; The fieldwork undertaken in the 2016-17 season focussed on providing geotechnical and environmental data to assist in site selection decisions for potential year-round aviation access infrastructure near Davis Station under AAD Year-Round Aviation Project 5097. The data acquired provided essential for engineering design, development of project delivery cost estimates, and core inputs to environmental impact assessments, developed to inform decisions on the feasibility of developing a year-round aviation access capability between Hobart and Antarctica.

This field season focussed on Heidemann Valley near Davis Station, with a geotechnical and hydrogeological drilling, sampling, mapping, geophysics, and surveying program. It also investigated an alternative potential site through surface sampling and mapping at the hard

2 Further details on the Australian Antarctic Strategy and 20 Year Action Plan, including commitments to a number of other projects that will enhance Australia’s support for scientific research, are available at: http://www.antarctica.gov.au/about- us/antarctic-strategy-and-action-plan

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rock Ridge Area north of the valley sites. Baseline environmental data was also collected from numerous lakes and Heidemann Bay Beach.

· Field Season 2017-18; The fieldwork undertaken in the 2017-18 season continued the collection of geotechnical and environmental data to assist in decisions on site selection for potential year-round aviation access infrastructure near Davis Station, and to inform potential future environmental impact assessments.

Given the information obtained from the 2016-17 Field Season, the main focus area for geotechnical testing was relocated from Heidemann Valley to the Ridge Area. Geotechnical testing was undertaken with person-portable borehole drilling equipment, involving excavation of test pits dug on the Ridge Area in areas where sediment covers bedrock, aerial surveys were undertaken via helicopter, native wildlife observations were undertaken with additional soil samples were collected for terrestrial and marine ecology studies.

· Field Season 2018-19; Work undertaken over the 2018-19 field season under the year-round aviation access project focussed on further refinement of the understanding of the geology and topography of the Ridge Area; a rocky topographically undulating landscape located about 5 km northeast of Davis Station. Geological, geomorphological, and geotechnical mapping, borehole drilling and excavation within sediments, and ground stability assessments further characterised key areas of the Ridge Site to assist informing engineering design and project delivery cost estimates. Environmental surveys at the Ridge Area, and wider Vestfold Hills, were also conducted and successful in surveying seabirds and seals and collecting samples to inform on terrestrial and benthic conditions in the context of potential environmental impact assessments.

Two field huts were constructed over the 2018-2019 season at the Ridge Site, adjacent to Camp Lake and still remain, to provide emergency shelter and refuge for expeditioners. These huts have proven a successful refuge for teams working on the Ridge, however these are not proposed for use as core project assets for the 2021-2022 field seasons. Further, the proposed runway centreline was surveyed and marked, with remote piloted aircraft (RPA) drone imagery capturing the alignment, wider Ridge Site & Adams Flat areas.

· Field Season 2019-20; The fieldwork undertaken in the 2019-20 season continued the collection of geotechnical and environmental data from the 2018-2019 season, to further assist in decisions on site selection and inform engineering design considerations for the Davis Aerodrome Project, and supplement inputs to environmental impact assessments associated with government approvals.

Noting the information obtained from previous phases of investigative works, the primary scope included visual assessment and mechanical excavation of test pits in Davis Link, Adams Flat and the Ridge Site to collect representative soil and rock samples further informing the understanding of the site conditions. Excavations of test pits were focussed to understand the sediment thickness and composition where it overlies the bedrock or permafrost.

In preparation for future site investigations and geotechnical drilling in 2021-2022, temporary access tracks to approximately 5.5m width have been formed, by clearance of material causing obstructions to vehicles, .

Based on the previous field assessments, a suitable site for a runway and associated infrastructure at the Ridge Site in the Vestfold Hills region of East Antarctica was nominated.

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With the Project in the process of developing delivery and procurement options, subject to government environmental approvals. 2.3 Davis Station Infrastructure Project Background

Geotechnical and environmental investigations are required to inform and support the work of the Australian Antarctic Division’s (AAD) Antarctic Assets & Infrastructure Branch (AIB). This work is to support a comprehensive assessment of the current Davis Station Infrastructure and surrounding station operations area (part of Strategic Infrastructure Project [SIP]) in support of the 20 Year Action Plan, to inform the future state of Davis Station.

In addition to the above, a suite of stabilisation and enabling works is to be considered at Davis Station to maintain capability and address existing and planned operations over the coming 2-5 years. The proposed activities presented within this IEE, will assist the planning and development of stabilisations works only, with a separate environmental application submitted prior to the commencement of any construction activities.

Past activities in support of infrastructure planning and development include:

· Field Season 2002-2003; The engineering division of the Australian Antarctic Division undertook a geotechnical investigation of an area at the head of Heidemann Bay, with the intention to comment on its engineering suitability for a VHF Radar Installation. The site is located with the flats of the Heidemann Valley, with the surface soils comprising of fluvioglacial deposits. The surface deposits are generally loose silty sands with surface boulders. The onsite geotechnical engineer carried out an investigation comprising the drilling of geotechnical boreholes, dynamic cone penetrometer tests and small-scale test-pit excavations, reflective of this proposed for the 2021-2022 season. A suite of laboratory testing was also undertaken on selected samples from the site.

· Field Season 2018-19; Geotechnical site investigations for an engineering improvement to the existing Davis Station wharf / boat ramp and a new container storage / handling area was undertaken. The investigation included geotechnical mapping, in situ testing and five test pit excavations, with representative samples processed and returned to Australia for testing.

· Field Season 2019-20; Geotechnical site investigations undertaken in 2019-2020 included manual and mechanical test pit excavations and dynamic cone penetrometer testing to support the development of engineering concepts for Davis Station stabilisation requirements. This site investigation focussed on the area to the north of the Meteorological Building and included investigations into alternative helicopter operation facilities in Heidemann Valley. 2.4 Statutory Requirements To ensure the protection of the Antarctic environment, the Antarctic Treaty nations adopted the Protocol on Environmental Protection to the Antarctic Treaty which came into force in 1998. Australia enforces the provisions of the Environmental Protocol through the Antarctic Treaty (Environment Protection) Act 1980 (ATEP Act) and Environmental Impact Assessment Regulations.

The Antarctic Marine Living Resources Conservation Act 1981 (AMLRC Act)implements the Convention of the Conservation of Antarctic Marine Living Resources. 2.5 Purpose and Scope of the Document The purpose of this IEE is to provide details of the proposed January 2021 to June 2022 field activities to support Project engineering design development, present their potential environmental impacts

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and document measures to minimise or avoid such impacts. This document contains the following sections:

· Section 3 describes the proposed activities · Section 4 describes the local environment · Section 5 describes the alternates considered · Section 6 describes the environmental impacts and the measures proposed to minimise or avoid them · Section 7 provides the conclusions of the IEE. A non-technical summary has been included at the beginning of the document to provide an overview of the IEE. 2.6 Previous Assessments and Obligations This IEE builds on Project work completed under previous IEE approvals. A number of sensors, instruments and equipment has been installed by the Project under previous environmental approvals. The items which remain insitu are documented in Table 1, with locations to be available upon request. It is proposed that this IEE reflect these legacy installations and carry these forward as remediation liabilities with appropriate remediation to be developed as part of ongoing short, medium- and long-term project remediation strategies, as required.

Quantity Installation Location

Approx. Access tracks to enable vehicle access to drill sites. Ridge Site, Adams Flat, 13km. Davis Link.

12x Lake markers – locations & map available at request. Ridge Site, Adams Flat, Davis Station

68x 900mm traffic cones. Ridge Site

Placed at 50m intervals along the proposed runway centreline (double cones placed at 500m intervals). 2x additional cones placed at relative construction height on Camp Knoll.

148x Stainless steel ‘sediment movement’ rods located across the Ridge Ridge Site Site with aerial markers and associated ground control points.

2x Melons (huts) fixed close to Camp Lake at WGS84 44S 380765mE Ridge Site 2393678mN

4x 900mm traffic cones. Davis Link

Marking end of access track (to be constructed over 2020 winter). Offset from high voltage cable.

4x Star pickets with permits attached. Ridge Site, Adams Flat.

4x McLennan Project (P4393 – 2019/19, 2019/20) –Human Impact Adams Flat, Lake Dingle, monitoring sites Heidemann Valley vicinity.

Table 1: DAP Previously Authorised Activities with Remediation Obligations (as at end 2020 winter)

MARCH 2021 11 INITIAL ENVIRONMENTAL EVAULATION 2021-2022 FIELD SEASONS 3 Description of the Proposed Activity 3.1 Aims and Objectives The primary Project objective for the 2020-21 summer, 2021 winter, and 2021-22 summer field seasons are to continue the collection of targeted geotechnical information through the drilling of boreholes, sampling of representative soil, rock and groundwater samples, excavation of manual and mechanical test pits, geophysical surveys and topographic / hydrographic surveys to inform the ongoing engineering design, inform constructability assessments, supplement environmental impact assessments and assist the procurement of the project delivery partners. 3.2 Overview of Proposed Activities 3.2.1 2020-21 Summer Program

A team of two DAP project personnel have remained at Davis over the 2020 winter and 2020/2021 summer, comprising a plant operator and project scientist, undertaking ongoing maintenance and operations activities approved under existing permits and approvals.

In preparation for the proposed 2021 winter program, activities will include preparation of access tracks, clearance of loose surficial material from proposed drill sites, and clearance of materials to facilitate a temporary plant and materials laydown area on the Ridge site. This will be undertaken by the same approach as previously, with large rocks relocated to enable access for vehicles and plant, adequate space for the drilling rig, and a location for the storage and staging of drilling consumables, plant, and shelters on the Ridge.

3.2.2 2021 Winter Program

The 2021 wintering project field team will replace the 2020 wintering team and comprise specialist geotechnical drilling subcontractor (2 persons), geotechnical engineer and plant operator deployed on Voyage 2, departing Hobart for Davis mid-February, and arriving late-February 2021. Project personnel requirements for the 2021/22 Summer season are to be determined and will be determined in collaboration with the project team and interfacing AAD Branches.

Upon arrival, resupply operations, station and project inductions and survival training activities are proposed to occur over the initial 10-14 days following arrival, with fieldwork commencing upon completion, pending environmental approval.

Fieldwork will continue until a few weeks prior to departure, estimated November 2021, with return to Hobart anticipated December 2021.

The 2021 Winter field program is proposed to comprise a number of components subject to weather and operational constraints, and nominally includes.

· Geotechnical borehole drilling and test pit excavation investigations. · Installation of in-situ monitoring instrumentation, and · Visual geological and geotechnical observations

3.2.3 2021-22 Summer Program Depending on the outcomes and productivity achieved over the 2021 Winter season, the 2021/22 summer scope will be defined by mid-2021. Based on anticipated outcomes, subject to weather and operational constraints, the following scope is nominally proposed: · Supplementary geotechnical borehole drilling and test pit excavation investigations. · Ongoing monitoring of in-situ geotechnical and hydrogeological instrumentation, · Visual geological and geotechnical observations, · Terrestrial and hydrographical survey, and MARCH 2021 12 INITIAL ENVIRONMENTAL EVAULATION 2021-2022 FIELD SEASONS

· Geophysical surveys 3.3 Location of the Proposed Activity Figure 1 defines the nominal areas of the proposed 2021-2022 Field Season activities, which will be undertaken within proximity of Marchants Landing, Davis Station Limits, Davis Link, Adams Flat, Heidemann Valley and the Ridge Site. Proposed geotechnical borehole and excavation locations are to be determined on site following receipt of environmental permit conditions, site terrain, weather, and access constraints.

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Figure 1 – Project Location Plan

MARCH 2021 14 INITIAL ENVIRONMENTAL EVAULATION 2021-22 FIELD SEASON 3.4 Nominal Sequence of Season Activities Based on the current communicated AAD Operational Programs and vessel departure dates, the following sequence of works is proposed in order to meet the project requirements.

Activity* Nominal Duration of Activity

Ongoing site preparation works (under existing environmental January 2021 approvals)

Deployment of plant, equipment, and personnel Mid February 2021

Station resupply activities Late February – Early March 2021

Commissioning and testing of geotechnical drilling equipment March – Early April 2021

Station safety training and site familiarisation Late March 2021

Drilling of select high priority geotechnical boreholes to April– June 2021 facilitate downhole instrumentation installation (Davis Link, Adams Flat and Ridge Site)

Drilling of medium priority geotechnical boreholes to facilitate June – August 2021 technical site understanding (Ridge Site, Adams Flat)

Drilling of low priority geotechnical boreholes to facilitate September – October 2021 technical site understanding (Davis Link, Davis Station, Marchants Landing and Heidemann Valley

Excavation of test pits to facilitate understanding of site October 2021 conditions (Davis Station, Davis Link and Heidemann Valley)

Monitoring of borehole instrumentation throughout the Monthly following installation season

Sample Processing and transport preparation October 2021

Equipment “Break-down” for transport Late October 2021

Return to Australia (RTA) of winter personnel, equipment, and Early November 2021 - TBC samples

Station resupply activities Early November 2021 - TBC

Delivery of remaining project activities November 2021 – February 2022 - TBC

RTA of summer personnel, equipment, and samples March 2022 - TBC

* Note – priorities of geotechnical drilling locations may change depending on site, engineering, program constraints and or opportunities. 3.5 Site Access and Preparation Prior to the proposed Project geotechnical site investigation activities commencing, a number of preparatory activities are deemed necessary, to facilitate the efficient delivery of the works, and

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15 INITIAL ENVIRONMENTAL EVAULATION 2021-22 FIELD SEASON proactively manage program and environmental risk in advance of the geotechnical drilling and excavation program. Site access and preparation tasks may include:

· Formation of temporary vehicle and plant access tracks of nominal 5.5m width, to sites of geotechnical interest within the project extents, requiring the clearance of surficial sediments and rocks causing vehicle obstructions to create temporary access tracks for geotechnical drilling equipment and support vehicles. Extents of additional access track formation are to be determined, however for the purposes of planning a nominal additional of 7500m is proposed, noting extents are to be minimised where possible to reduce environmental disturbance and impact. Visual reinstatement of ground disturbance are proposed to be undertaken upon completion of the program, in addition to documentation of photographic records of pre- and post- work conditions. · Formation of temporary working areas to provide a safe and functional environment for field staff at each borehole location up to ~150m2 within Marchants Landing, Davis Station limits, Davis Link, Adams Flat, Ridge Site and Heidemann Valley. To safely undertake the proposed drilling works, temporary relocation of surficial material within the drilling working platform may be required. Visual reinstatement of ground disturbance are proposed to be undertaken upon completion of the program, in addition to documentation of photographic records of pre- and post-work conditions. · Placement of asset and utility protection culverts to facilitate vehicle and plant access. It is anticipated 15 asset protection culverts are required to be placed over existing on ground assets to prevent damage associated with vehicle access within Davis Station limits. Locally sourced crushed rock, from existing station stockpiles, will be used to backfill and provide support the works. Assets requiring protection may include power, communications, water, and infrasound cables. Visual remediation of ground disturbance are proposed to be undertaken upon completion of the program, in addition to documentation of photographic records of pre- and post-work conditions. · Clearance of surficial materials and obstructions, to facilitate up to 5 temporary works storage areas within the project areas, to reduce excessive haulage distances and minimise environmental impacts. These areas of nominally 100m2 each, are proposed to facilitate project works within Davis Link, Adams Flat and the Ridge Site. Visual reinstatement of ground disturbance are proposed to be undertaken upon completion of the program, in addition to documentation of photographic records of pre- and post-work conditions.

It is proposed these activities will commence during the 2020-21 summer season and continue into the 2021-2022 future field season(s) as required. 3.6 Geotechnical Investigations 3.6.1 Borehole Drilling 3.6.1.1 Overview To provide the integral geotechnical information to inform the ongoing planning, engineering design and delivery of the Project, a targeted geotechnical drilling program has been developed based on the project concepts, anticipated ground conditions and areas of greater geotechnical risk and uncertainty. The approach to define geotechnical scope has been developed on the principles of maximising the quality and quantity of geotechnical information to inform stages of the project life cycle, while minimising potential environmental impacts and disturbance. To deliver the geotechnical drilling program for the Project, a specialist geotechnical drilling sub-contractor with proven experience in remote, polar environments has been engaged in accordance with AAD procurement guidelines.

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During the 2017-18 summer season, the Project successfully drilled ten cored geotechnical boreholes to a depth of approximately 10 m below existing surface, with a core diameter of up to 70 mm. The intent of this investigation was to determine continuity of the rock to depth and to collect geotechnical information and samples.

Utilising the information acquired from the 2018/19 season, the project has procured specialist drilling equipment and personnel with proven experience in similar ground conditions and working environments. The Project proposes to deliver the scope of work, by utilising a rotary drilling rig, mounted within a purpose built skid trailer to drill boreholes to ensure the recovery of suitable soil and rock core samples, up to 100mm diameter to depths up to 60m below existing surface. The purpose of such investigations are to further develop the project understanding of the site conditions and assist in the management of technical and construction risk by:

· assessing the depth and composition of the unfrozen soils from ground surface to permafrost · assessing the thickness and composition of the soils within permafrost layer(s), if encountered · measuring the depth to basement rock · assessing the lithology, structure, and composition of the existing bedrock. The co-ordination and sequencing of the geotechnical drilling program has been developed to prioritise locations of interest, and to utilise the changing weather conditions to the field teams’ advantage to minimise environmental impacts and to acquire the relevant samples and information.

The intention will be to focus the drilling of higher priority locations earlier in the program, notably in the vicinity of Adams Flat, Camp Lake Valley and East Valley. Focussing efforts on locations where downhole monitoring instrumentation is proposed, will allow the project team to acquire seasonal information available to share with the project delivery team as required. In addition, where there is the potential for activities to induce ground disturbance due to soft and unfrozen ground conditions in Summer, works are to be sequenced to undertake drilling activities in the cooler months, where there is greater potential for surfaces to be frozen and less susceptible to disturbance.

The program is to be delivered by specialist a geotechnical drilling contractor with a proven history of delivering complex and challenging geotechnical drilling programs in remote, polar conditions. The skills and knowledge they will bring to the project are anticipated to maximise the quality of the drilling works, optimise the speed of project delivery, and ensure adverse environmental impacts are minimised.

The Zinex A5 drilling rig proposed to be mobilised for the program has successfully been deployed on drilling programs in the northern hemisphere Arctic since 2012 and have proven reliability under adverse environmental conditions. With the flexibility of the drilling rig to be mounted on a skid or wheeled trailer, depending on existing surface conditions, the “set-up” and “take-down” time between drill sites will be reduced minimise environmental disturbance. The drilling unit is equipped with outriggers to level the drill and have the option for large all terrain wheels to assist with mobilization in the rockier areas, or ‘broken down’ into modules and transported by telehandler or helicopter depending on accessibility constraints. Figure 2. Geotechnical drilling is proposed to be undertaken by a single drilling rig and crew, with operations limited to a single location at a time, with works aligned to standard Station operating hours. Additional equipment will be mobilised to accommodate contingency and redundancy requirements.

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The dimension of the skid mounted drilling trailer is approximately 4m in width by 6m in length, with the supporting equipment and plant module, containing drilling rig power sources approximately 2.5m in width and 6m in length. The supporting container is capable of being located at distance from the drilling trailer in the event site conditions require. The arrangement of drilling equipment on site will be positioned to maximise staff safety considerations, while minimising environmental impacts. Site arrangements will be assessed on a site-by-site basis depending on weather and topographical constraints and environmental sensitivities.

Figure 2 – Example of typical Zinex A5 Drilling Rig and Setup

Continuing from the approach adopted from historical geotechnical drilling programs at Davis, to facilitate the drilling process seawater is proposed to be used as the primary drilling fluid medium to lubricate the borehole and ensure core recovery. Seawater would be sourced from Prydz Bay in the vicinity of Davis Station, Heidemann Bay or West Bay, as required. Multiple locations have been nominated, refer to Section 3.8.3, with the intention to reduce haulage distances and durations and optimise project efficiencies as these will collectively reduce environmental impacts associated with vehicle emissions and ground disturbance. Seawater is proposed to be pumped into intermediate bulk containers (IBC’s) for storage and transportation by vehicle or helicopter to the required drilling location.

To facilitate coring at the deeper borehole locations, the potential may arise to require the salinity of the drilling fluids to be increased, to reduce the potential for the drilling fluids to freeze while below the surface. Reflective of the drilling methodology successfully deployed and approved in 2013 and 2016, it is proposed that calcium chloride is added to the seawater where required, to prevent the freezing of drilling equipment into the borehole and facilitate sample retrieval, with the solid drill cuttings (sediment having fallen out of drilling fluid suspension) removed to reduce the potential for MARCH 2021

18 INITIAL ENVIRONMENTAL EVAULATION 2021-22 FIELD SEASON plant damage during operations. Where downhole instrumentation is not proposed to be installed at the borehole location, the rock cuttings are proposed to be returned into the borehole, the environment in which they originated, upon completion of works. Where this approach is not possible, drill cuttings are to be treated as Landfill waste in accordance with AAD Waste Management Procedures. Discharge of excess seawater-based drilling fluids, nominally 1200 litres per borehole location, where unable to be directly removed from the treaty area, is proposed to be directly discharged to the marine environment in a manner that takes into account the assimilative capacity of the receiving marine environment. The discharge location is to be nominated in collaboration with AAD Science Branch and focused to locations where conditions exist to promote dilution and rapid dispersal, to minimise adverse impacts on local marine ecosystems or species. Where practicable additional measures will be employed to reduce residual risks of impacts to the marine environment, including reducing sedimentation and other contaminant material in the fluid.

It is proposed the drilling water remaining within the borehole is allowed to freeze, to form a natural backfill material, with the upper section capped at surface with local sediment, drill cuttings and cementiceous grout to negate the potential for native vertebrate entrapment and facilitate visual remediation of the site.

Figure 3a and Figure 3b summarise the nominal, high priority borehole location plans based on anticipated conditions. The final locations are to be assessed prior to works, dependent on environmental and operational factors.

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Figure 3a – Nominal High Priority Borehole Locations (Davis Station, Davis Link and Adams Flat)

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Figure 3b – Nominal High Priority Borehole Locations (Adams Flat and Ridge Site)

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3.6.1.2 Marchants Landing To assess the ground conditions at locations of interest to support the potential Davis Station stabilisation works, the drilling of geotechnical boreholes at up to 10 locations is proposed. Locations are to be prioritised with locations and depths proposed based on engineering design requirements, reviewed mid-2020. Based on the anticipated form of engineering structures and ground conditions, the boreholes are proposed to be drilled to maximum depths of 25m below ground level (mbgl) with Recovered soil and rock samples to be visually described, photographed, and retained for laboratory testing upon RTA.

3.6.1.3 Davis Station Limits The targeted site investigation to assess the ground conditions at locations of the proposed Station wharf, enabling and stabilisation infrastructure, includes the drilling of geotechnical boreholes at up to 15 locations within Davis Station Limits. The boreholes are to be drilled to a maximum depth of 25m below ground level (mbgl), with recovered soil and rock samples to be visually described, photographed, and retained for laboratory testing upon RTA. Locations have been prioritised and proposed based on the engineering concept design and the anticipated ground conditions, with the view to maximise the geotechnical understanding of the site and minimise environmental impacts and project delivery risk.

3.6.1.4 Davis Link The targeted site investigation includes the drilling of geotechnical boreholes at up to 15 locations within Davis Link to inform the design of the Aerodrome access track. The boreholes are anticipated to be drilled to a maximum depth of 15m below ground level (mbgl), with recovered soil and rock samples to be visually described, photographed, and retained for laboratory testing on station or up on RTA. Locations have been prioritised and proposed based on the engineering concept design and the anticipated ground conditions, with the view to maximise the geotechnical understanding of the site and minimise environmental impacts and project delivery risk.

3.6.1.5 Heidemann Valley The proposed geotechnical program includes the drilling of boreholes at up to 10 locations within Heidemann Valley and the surrounding hinterland, to inform the design of temporary construction compounds and temporary access tracks. The boreholes are anticipated to be drilled to a maximum depth of up to 20m below ground level (mbgl), with recovered soil and rock samples to be visually described, photographed, and retained for laboratory testing on station or upon RTA. Locations have been prioritised and proposed based on the engineering concept design and the anticipated ground conditions with the intention to maximise the geotechnical understanding of the site and minimise environmental impacts and project delivery risk.

3.6.1.6 Adams Flat The targeted site investigation includes the drilling of geotechnical boreholes at up to 20 locations within Adams Flat to inform the design of the Aerodrome access track and High Intensity Aviation Lighting (HIAL) structures. The boreholes are anticipated to be drilled to a maximum depth of up to 25m below ground level (mbgl), with recovered soil and rock samples to be visually described, photographed, and retained for laboratory testing on station or upon RTA. Locations have been prioritised and proposed based on the engineering concept design and the anticipated ground conditions with the intention to maximise the geotechnical understanding of the site and minimise environmental impacts and project delivery risk.

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3.6.1.7 Ridge Site The targeted site investigation includes the drilling of geotechnical boreholes at up to 80 locations within the Ridge Site to inform the design of the Aerodrome including runway, runway embankment, ancillary aviation, and operation buildings and HIAL structures. The boreholes are anticipated to be drilled to a maximum depth of up to 60m below ground level (mbgl), with recovered soil and rock samples to be visually described, photographed, and retained for laboratory testing on station or once RTA. Locations have been prioritised and proposed based on the engineering concept design and the anticipated ground conditions with the intention to maximise the geotechnical understanding of the site and minimise environmental impacts and project delivery risk.

3.6.2 Borehole Instrumentation Installation and Monitoring 3.6.2.1 Overview To supplement the existing long term geotechnical and environmental downhole monitoring instrumentation currently installed in Heidemann Valley and Adams Flat, up to 60 downhole monitoring instruments are proposed, which include borehole ground temperature arrays (thermistors), groundwater level monitoring and soil movement instrumentation.

Where multiple downhole instruments are nominated for installation at the same location, and it is not possible to accommodate them in a single borehole, it is proposed a secondary borehole is drilled within the same cleared borehole working area, to the target depth without the collection samples or geotechnical logging. It is proposed a secondary borehole is drilled at up to twenty locations, with secondary locations considered as part of the overall borehole quantum.

Following the installation of the instrumentation upon completion of the borehole, a weatherproof monument style cover, Figure 4, will be placed over the borehole with provision made for an integrated datalogger, with the purpose to reduce the requirement for access at greater frequencies, mitigate environmental impacts associated with ground disturbance, reduce the potential for native fauna entrapment and reduced the potential for the PVC mounted instrumentation from becoming impacted by solar and climatic impacts.

Figure 4 – Typical Monument Style Borehole Enclosure

The approach to decommissioning and reinstatement of boreholes containing monitoring equipment is proposed in line with broader project remediation strategies. The potential for retaining the

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23 INITIAL ENVIRONMENTAL EVAULATION 2021-22 FIELD SEASON instrumentation may also be considered upon completion of the works, as opportunities associated with medium- and long-term monitoring may be realised. It is proposed the boreholes containing instrumentation are be remediated upon completion of their operable use. Remediation methods may include mechanically pulling the materials from the borehole and where necessary or over-drilling of the borehole, to remove all remaining instrumentation materials including PVC casings. Methods deployed during this activity will negate potential for dispersal of waste materials to the environment, namely microplastics, utilising specialise borehole decommissioning techniques in accordance with accepted industry and environmental regulator intentions.

3.6.2.1.1 Ground Temperature Monitoring Instrumentation (Thermistors) It is anticipated a total of 23 thermistor strings are to be installed within the boreholes, with the intention to assist in the determination of the potential thickness and progression of the permafrost and ‘Active Zone’ horizons. Locations nominated for thermistor installation are to be determined on site based on the results of the observations made from the recovered core samples.

To ensure consistent data, and to mitigate the potential for instrument malfunction, it is suggested duplicate thermistor strings are placed in 10 of the 23 selected locations.

As proposed, to facilitate continual seasonal monitoring, dataloggers are proposed to record the evolution of ground temperature over time. The dataloggers are battery powered to reduce the need for a separate power source and are to be encased within a weather protective casing to mitigate environmental impacts and native fauna entrapment.

Aligned with the approach adopted in broader polar regions, the thermistor equipment is proposed to be lowered down the borehole fixed to a thin PVC piping to provide columnar support. PVC is proposed for use to be utilised to be in alignment with industry standard methodologies Mitigation measures to prevent to dispersion of microplastics associated with cutting and preparation of PVC is discussed in Section 6.2.2.2.

Approach to remediation is articulated in Section 3.6.2.1.

3.6.2.1.2 Groundwater Level Monitoring Instrumentation It is anticipated a total of 14 groundwater level monitoring instruments are to be installed within selected boreholes in the Davis Link, Adams flat and Ridge Fill Zone areas, to provide greater understanding of the existing groundwater regime and hydraulic conductivity of the sediments. Locations nominated for thermistor installation are to be determined on site based on the results of the observations made from the recovered core samples, with instruments installed to depths up to 20m below existing ground level

Within the selected locations, primarily on the Ridge Site and Adams Flat, groundwater level dataloggers will be installed to shall allow for site visits to record changes in groundwater level over time. The dataloggers are battery powered to reduce the need for a separate power source and are to be encased within a weather protective casing to mitigate environmental impacts and native fauna entrapment.

The monitoring well locations and depths will require the downhole placement of sand as a filter medium, in addition to low permeability material grout (e.g. cementiceous bentonite grout) to isolate discrete stratigraphic zones for assessment.

Aligned with the approach adopted in broader polar regions, the groundwater monitoring datalogger is to be lowered down the borehole within a PVC threaded casing, encased within a 3m thick graded,

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24 INITIAL ENVIRONMENTAL EVAULATION 2021-22 FIELD SEASON coarse quartz sand filter medium section underlying a 1m thick impermeable seal. The remainder of the borehole shall be grouted to surface using cementiceous bentonite grout. At the surface, the bore shall be capped to minimise environmental impacts during the monitoring period.

Approach to remediation is articulated in Section 3.6.2.1.

3.6.2.1.3 In-situ Hydraulic Conductivity Testing It is anticipated a total of 12 in-situ hydraulic conductivity tests are to be undertaken within the selected boreholes in the Davis Link, Adams Flat and Ridge Site areas to provide further understanding of hydraulic permeability and conductivities within the upper sediment horizons, with instruments installed to depths up to 20m below existing ground level. Rising and/or Falling Head tests are proposed to be undertaken within the same borehole the dataloggers (as detailed in the previous section).

Rising head tests require the removal of a volume of groundwater, with the time recoded for the water to return to initial levels. The removed column of water can be captured on site for reuse. Depending on stratigraphy and encountered groundwater levels relative to the base of the borehole, Falling Head tests may be proposed, which require the addition of a column of water, with the time recorded for the level of dissipate to initial levels. Seawater is proposed without the introduction of drilling additives, to minimise potential adverse changes in groundwater chemistry.

3.6.2.1.4 Time Domain Reflectometry (TDR) It is anticipated a total of 11 TDR monitoring arrays are proposed to be installed within the drilled boreholes in the Davis Link, Adams Flat and Ridge Site areas. The Project understands that the sediments infilling Camp Lake and East Valleys are migrating downslope through soil creep/freeze-thaw processes. The TDR instrumentation is proposed to assist in defining the rate of movement and any potential seasonal fluctuations. To date, no previous monitoring has been undertaken to assess the rate of sediment movement at the surface or depth. For engineering design, the mode and rate of movement is important to understand, as it may influence the detailed design of the runway’s embankment introducing greater adverse environmental impacts during or after embankment construction.

Equipment required to be installed within the borehole to facilitate TDR testing includes co-axial cable fixed to a PVC guide tube and encased within a weak cementiceous grout. Dataloggers are proposed to be installed to record movement over time. The dataloggers are battery powered to reduce the need for a separate power source and are to be encased within a weather protective casing to mitigate environmental impacts and native fauna entrapment.

Approach to remediation is articulated in Section 3.6.2.1.

3.6.3 Downhole Instrumentation Quantum 3.6.3.1 Marchants Landing · 2 x boreholes with thermistor instrumentation · 2 x boreholes to facilitate groundwater level monitoring · 2 x boreholes with hydraulic conductivity testing

3.6.3.2 Davis Station Limits · 2 x boreholes with thermistor instrumentation · 2 x boreholes to assist in groundwater level monitoring · 2 x boreholes with hydraulic conductivity testing

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3.6.3.3 Davis Link · 2x boreholes with thermistor instrumentation · 1 x borehole with TDR instrumentation

3.6.3.4 Heidemann Valley · 2 x boreholes with thermistor instrumentation · 2 x boreholes to assist in groundwater level monitoring · 2 x boreholes with hydraulic conductivity testing · 2 x borehole with TDR instrumentation

3.6.3.5 Adams Flat · 3 x boreholes with thermistor instrumentation · 1 x borehole to assist in groundwater level monitoring · 1 x borehole with hydraulic conductivity testing · 1 x borehole with TDR instrumentation

3.6.3.6 Ridge Site · 12 x boreholes with thermistor instrumentation · 7 x Groundwater Monitoring · 5 x boreholes with TDR instrumentation · 7 x boreholes with hydraulic conductivity testing

3.6.4 Test Pit Excavation To supplement to the historical test pit excavation activities undertaken to date, and to acquire soil samples of greater volume than provided from borehole drilling processes, further mechanical and manual test pit excavations are proposed throughout the Project site in order to further visually assess geotechnical ground conditions and collect bulk soil samples of in-situ material for geotechnical testing and analysis. Based on the current engineering concept, manual and mechanically dug test pits are proposed to be undertaken at targeted locations.

Manually excavated test pit locations are to be accessed by foot, with mechanically excavated test pits undertaken along the temporary access tracks formed to support the borehole drilling activity, consistent with historical fieldwork methodologies. The remediation of mechanical and manual excavations will be completed by backfilling with excavated spoil to minimise environmental impacts, and to tamp the surface with the excavator bucket or hand tools upon completion. Examples of test pit reinstatement efforts undertaken to date, are presented in Figures 5 to 9.

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Figure 5 - Manual Test Pit Location Prior to Works

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Figure 6 – Manual Test Pit Excavation

Figure 7 - Manual Test Pit Excavation Upon Reinstatement

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Figure 8 - Mechanical Test Pit Site Prior to Works

Figure 9 - Mechanical Test Pit Site Upon Reinstatement (Access Track Reinstatement Not Complete in Image)

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3.6.4.1 Marchants Landing Up to 15 mechanically excavated (or manually excavated where vehicle access is constrained) test pits, of up to 1.2m width and 4m in length ,to a nominal depth of 4m below ground level or mechanical refusal will be undertaken using the excavator bucket only, to assess the existing ground condition in the vicinity of Marchants Landing to the south of Davis Station, to inform strategic infrastructure and master planning activities.

To supplement the geotechnical observations and collection of representative bulk soil samples for strength and consolidation testing, the ground conditions will be assessed for strength using a DCP, as described in Section 3.5.5.

3.6.4.2 Davis Station Limits 45 mechanically excavated (or manually excavated where vehicle access is constrained) test pits, to a nominal depth of 4m below ground level or mechanical refusal will be undertaken using the excavator bucket only, to assess the existing ground condition in the vicinity of the proposed Davis Station wharf, enabling and stabilisation infrastructure to inform engineering design.

To supplement the geotechnical observations and collection of representative samples, the ground conditions will be assessed for strength using a DCP, as described in Section 3.5.5.

3.6.4.3 Davis Link 10 mechanically excavated (or manually excavated where vehicle access is constrained) test pits, to a nominal depth of 4m below ground level or mechanical refusal will be undertaken using the excavator bucket only, to assess the existing ground condition in the vicinity of the proposed Access Road from Davis Station to the Aerodrome.

To supplement the geotechnical observations and collection of representative samples, the ground conditions will be assessed for strength using a DCP, as described in Section 3.5.5.

3.6.4.4 Heidemann Valley 20 mechanically excavated (or manually excavated where vehicle access is constrained) test pits, to a nominal depth of 4m below ground level or mechanical refusal will be undertaken using the excavator bucket only, to assess the existing ground condition in the vicinity of the proposed Access Road from Dingle Road to potential temporary construction laydown and storage area.

To supplement the geotechnical observations and collection of representative samples, the ground conditions will be assessed for strength using a DCP, as described in Section 3.5.5.

3.6.4.5 Adams Flat 30 mechanically excavated (or manually excavated where vehicle access is constrained) test pits, to a nominal depth of 4m below ground level or mechanical refusal will be undertaken using the excavator bucket only, to assess the existing ground condition in the vicinity of the proposed Access Road from Davis Station to the Aerodrome.

To supplement the geotechnical observations and collection of representative samples, the ground conditions will be assessed for strength using a DCP, as described in Section 3.5.5.

3.6.4.6 Ridge Site 50 mechanically excavated (or manually excavated where vehicle access is constrained) test pits, to a nominal depth of 4m below ground level or mechanical refusal will be undertaken using the excavator bucket only, to assess the existing ground condition in the vicinity of the proposed Aerodrome alignment and supporting infrastructure. MARCH 2021

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To supplement the geotechnical observations and collection of representative samples, the ground conditions will be assessed for strength using a DCP, as described in Section 3.6.5.

3.6.5 Dynamic Cone Penetrometer testing Dynamic Cone Penetrometer (DCP) testing provides a quick and relatively straightforward manual method to investigate subsurface soil conditions and assessing depth to permafrost, by measuring the penetration of the device into the soil after impact from integrated 6kg falling weight. The DCP is an effective tool for assessing surface characteristics in a sedimentary environment, shown in Figure 10.

It is proposed DCP testing is undertaken in areas of significant geotechnical interest adjacent to each test pit and where volumes of engineered fill are anticipated to be placed to facilitate construction.

Figure 10 - Dynamic Cone Penetrometer (on ground)

3.6.6 Geological Mapping and Geotechnical Visual Observations Aerial imagery and geological mapping from previous seasons efforts have shown that rock quality and geological structure varies throughout the project extents. These variations can influence how the soil and rock will respond to excavation, crushing, and its utility as embankment fill. Examining and quantifying these variations in the way the rock might behave during construction is required for construction planning and engineering design.

Prior to commencing fieldwork, it is proposed to use aerial imagery and existing site observations to identify suitable, accessible locations where greatest quality of geotechnical and geological information can be recorded. Records of the following are likely to be undertaken throughout the season:

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· Assessment of areas where rock is visible through shallow sediment (nominally <1 m thickness of sediment) versus those where it is thicker. · Mapping visible geological faults, especially those identified from previous field seasons, which may result in lower rock strength than for surrounding materials.

3.6.7 Geophysical Survey The purpose of geophysical surveys are to assist in the characterisation of subsurface conditions, primarily within the unconsolidated soil sediments overlying rock by using non-ground-breaking methods. The information will be used to aid in the engineering design development of the Project, specifically in areas where fill is required to be placed to support project infrastructure, but also in areas underlain bedrock. Geophysical surveying is proposed to be performed compliment the borehole and text pit excavation activities, in assisting with the identification and characterization of the following:

· Depth of bedrock from existing surface. · Depth to and thickness of various stratigraphic zones including lithologic, permafrost, saturation, and potential aquifers below permafrost layer, if present · Refinement of geotechnical engineering design parameters and collection of information relating to sediment behaviour; and · Monitoring of groundwater movement/freeze-thaw cycle effects in the sediments as a secondary objective.

The geophysical survey methods proposed to be undertaken include Seismic Refraction (SR), Multi- Analysis of Surface Waves (MASW), Electrical Resistivity Imagery (ERI) and Ground Penetrating Radar (GPR). When these survey methods are undertaken as a suite, a greater understanding of the ground conditions is developed.

3.6.7.1 Seismic Refraction and Multichannel Analysis of Surface Wave Surveys It is proposed geophysical surveys to collect both Seismic Refraction (SR) and Multichannel Analysis of Surface Wave (MASW) data are proposed at targeted locations throughout the Project area. The number, locations, and lengths of the survey transects will be optimized following a review of the geotechnical drilling program observations. For planning purposes, it is proposed a nominal allowance of ~20,000 linear meters of SR and MASW survey is made.

Evaluation of seismic refraction compressional wave velocities, as inferred from the recorded first arrival travel times and seismic velocity contrasts, will be primarily used to provide information pertaining to the configuration and depths of the subsurface geological units.

The MASW method provides an effective means of characterizing shear wave velocities of subsurface materials, through analysis of the dispersion of surface waves. Dispersion refers to the principle that the velocity of a seismic surface wave varies as a function of the frequency of the waveform. The dispersive characteristics of surface waves are directly related to variations in physical properties of the underlying geological layers. The shear wave velocities will be utilized to help facilitate the development of geotechnical design parameters through correlations between values and other in-situ and laboratory tests.

3.6.7.2 Electrical Resistivity Imaging Survey Electrical Resistivity Imaging (ERI) data will be collected throughout the Project site, with the number, location, and lengths of transects optimized following a review of the proposed geotechnical drilling program. For planning purposes, it is proposed a nominal allowance of ~20,000 linear meters of ERI survey is made. The ERI datasets will be used to provide valuable stratigraphic and geotechnical

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32 INITIAL ENVIRONMENTAL EVAULATION 2021-22 FIELD SEASON information of the sediment over rock and shallow bedrock and can be used to assess groundwater/freeze-thaw cycle effects.

The ERI method provides a rapid means of measuring electrical resistivity of subsurface materials, where soil and rock act as electrical insulators and are highly resistive. The flow of electrical current is primarily through moisture-filled pore spaces, with the observed resistivity controlled by rock composition, porosity, permeability, amount of water within the pore spaces, and the concentration of dissolved solids within the pore fluids. Therefore, resistivity measurements yield useful information for the characterization of the stratigraphy, structure, and composition of the subsurface.

3.6.7.3 Ground Penetrating Radar Surveys Ground Penetrating Radar (GPR) data is proposed be collected throughout the Project area with the number, location, and lengths of the transects determined following a review of the information collected as part of the 2021 Winter geotechnical borehole drilling and excavation program. For planning purposes, it is proposed a nominal allowance of ~20,000 linear meters is made. The GPR datasets will be used to provide valuable high-resolution stratigraphic information of the sediment over rock and shallow bedrock within the project areas

The GPR method involves transmitting electromagnetic pulses into the subsurface and recording the subsequent reflected signal, with electromagnetic pulses primarily influenced by the dielectric properties of subsurface materials. Reflection of the transmitted energy back to the GPR antenna occurs at interfaces exhibiting varying dielectric contrasts, while some of the transmitted energy is lost to attenuation and signal degradation. In this application, contrasts in dielectric properties typically correspond to variations in soil type, rock type, and ground water content.

3.6.8 Near-surface Water Flow Investigations Near-surface water flows above the permafrost layer, within the Camp Lake Valley and East Valley sediments, are likely to be contributing to the saturation and reduction in soil strength, leading to soil creep movement of these sediments’ downslope. Understanding the source and volume of water will assist in the prediction of ground and groundwater conditions during, and following, aerodrome construction. Importantly, not only can the management of water prevent slope instability of runway embankment, but also the sediment supporting an embankment.

To estimate near-surface flows, it is proposed that a series of up to 15 shallow (<1.5 m deep, up to 3 m wide) weirs are excavated, oriented across but sloping slightly down Camp Lake and East Valleys, reflective of the initial works undertaken in 2018/2019. These weirs will direct near-surface water flow across temporary ‘V-Notch’ gates, cut into plywood installed at the end of the weir, to measure surface flow rates. The ply-wood sheets (or similar) temporarily pinned into the ground with rods required to ensure stability and integrity.

Instantaneous flow rates can be measured by recording the height of water flowing over the gate. A holding / discharge basin, less than 1.5m in depth and up to 3m wide is required to be excavated immediately upstream of the gate, to act as a temporary surface water storage.

Additional ply-wood sheets can also be used as temporary surface cover, to prevent vertebrate fauna from entering the pits.

3.6.9 Lake and Waterbody Depth Monitoring

Similar to previous fieldwork seasons, the Project proposes to install simple water level gauges mounted on metal stakes around formed lakes and ephemeral waterbodies to visually monitor

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33 INITIAL ENVIRONMENTAL EVAULATION 2021-22 FIELD SEASON levels. Up to 20 water level gauges, consisting of tide gauges fixed to a metal stake, with depth levels visually recorded to identify potential fluctuations associated with recharge from snow and permafrost melt and discharge from over-spill and evaporation.

It is proposed visual monitoring will occur weekly, or opportunistically depending on the location of adjacent fieldworks and weather conditions. . To negate the potential for cross microbial contamination, water depth instrumentation will be thoroughly cleaned between deployment in lakes and /or waterbodies. 3.7 Surveys To support the ongoing construction planning and engineering design of the Project, it is proposed further terrestrial and hydrographic surveys are undertaken onshore and offshore respectively, in the vicinity of the project areas to define existing ground surfaces, environmental features and anthropogenic structures.

3.7.1 Terrestrial Survey Supplementing the existing survey information acquired over previous seasons, further geospatial studies will be required within the proposed project extents, to update and refine the survey of the existing surface conditions on which to inform the engineering design.

The project proposes to utilise an RPA (drone) to facilitate high quality aerial photography and photogrammetry, in accordance with processes defined within AAD’s Aviation Standard Operating Procedure (Volume 5). To compliment aerial photogrammetry surveys, additional real time kinematic equipment and laser scanning technologies using GPS data, similar to the approach adopted in 2019- 2020 is proposed.

3.7.2 Hydrographic Survey To assist in the development of an understanding of the offshore and nearshore approaches to Davis, surrounds and the profile of the existing lakes and waterbodies, hydrographic surveys are proposed using single beam or multibeam echosounder technologies. This supplementary information will assist the project construction planning and engineering design. 3.8 Equipment, Logistics and Methods of Proposed Activities. A detailed description of each aspect of the proposed 2021-2022 field season works are provided below and summarised in Appendix 1.

3.8.1 Site Access and Preparation The field team proposes to undertake the preparatory works to enable drilling rig access to the nominated borehole drilling sites, formation of temporary working areas prior to the arrival of the geotechnical drilling equipment on station and installation of asset protection culverts to maximise program opportunities and minimise potential environmental impacts.

· Location(s): Marchants Landing, Davis Link, Adams Flat, Ridge Site and Heidemann Valley · Number of sites: Minimum required to meet project objectives. · Frequency: Works to be undertaken prior to arrival of geotechnical drilling equipment, where possible and as coordinated between Field Coordinator, Station Operations Coordinator and Station Leader · Logistics, transport, and equipment: Ute, light vehicle, light truck and Hagglunds where practical. Station 30T excavator will be required to undertake any potential temporary surface

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obstruction clearance. Station telehandler is anticipated to be required to facilitate in the placement of asset protection culverts as required. · Methodology: Alignments and locations of temporary site laydown areas, working platforms and culverts are to be visually assessed for operational and environmental suitability prior to works. · Areas are to be assessed for environmental sensitivities, including potential for avian habitation. · Works are to be undertaken in accordance with: o Work Health and Safety requirement documented within Chapter 1 of the Operations Manual Volume 1: Station and Field which presents key WHS principles and practices that must guide all work on-station and in the field in the Antarctic and sub-Antarctic. o Environmental Protection and Management documented within Chapter 2 of the Operations Manual Volume 1: Station and Field which details environmental management issues in both station and field locations and provides information on: § first response to emergency response § environmental policy and the framework that guides operations § environmental roles and responsibilities § annual audits, exercises and stocktakes to ensure preparedness for issues. · To document evidence of visual remediation activities, pre- and post-work photographs are to be recorded to detail efforts undertaken to minimise adverse impacts associated with ground disturbance 3.8.2 Geotechnical Borehole Drilling The field team will conduct a geotechnical drilling program utilising a skid mounted drilling rig to collect subsurface soil and rock core samples to obtain geotechnical data necessary to inform the engineering design.

· Location(s): Marchants Landing, Davis Station limits, Davis Link, Adams Flat, Heidemann Valley and the Ridge Site · Number of sites: Up to 150 sites. · Frequency: Works to be undertaken on a daily basis as coordinated between Field Coordinator, Station Operations Coordinator and Station Leader · Logistics, transport and equipment: Ute, light truck, low pressure excavator / bulldozer, Hagglunds or Helicopter support where practical, geotechnical drilling rig and ancillary equipment (including but not limited to; portable pumps, generators, ute and trailer, core trays, sampling equipment and weather shelter). · Methodology: Following formation of the working area (as detailed in Section 3.8.1) The following activities are proposed: o Areas are to be assessed for environmental sensitivities, including potential for avian habitation. o Drilling unit will be positioned to minimise potential environmental impacts and ensure personnel safety measures are addressed. o Drilling unit is to be levelled using outriggers to accommodate sloping surface topography. o Rotary drilling techniques are to be adopted to facilitate the recovery of soil and rock cores of up to 100mm diameter and 60m in depth

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o Seawater, supplemented with drilling additives (e.g. calcium chloride and/or viscosifiers) where required, may be used to maximise drilling efficiency leading to a reduction in potential environmental disturbance associated with borehole collapse and increased requirement for water cartage. Volume of water required to support the drilling activities will be dependent on the borehole depth and the encountered ground conditions inducing dissipation to ground, with daily volumes anticipated to be less than 5000 litres per working day o Recovered samples are to be visually logged and photographed on site and taken to Davis Station for geotechnical testing and packaging for RTA. Total volume of samples to be collected is discussed in Section 3.7.16. o Works are to be undertaken in accordance with: § Work Health and Safety requirement documented within Chapter 1 of the Operations Manual Volume 1: Station and Field which presents key WHS principles and practices that must guide all work on-station and in the field in the Antarctic and sub-Antarctic. § Environmental Protection and Management documented within Chapter 2 of the Operations Manual Volume 1: Station and Field which details environmental management issues in both station and field locations and provides information on: · first response to emergency response · environmental policy and the framework that guides operations · environmental roles and responsibilities · annual audits, exercises and stocktakes to ensure preparedness for issues. o To document evidence of visual remediation activities, pre- and post-work photographs are to be recorded to detail efforts undertaken to minimise adverse impacts associated with ground disturbance o Installed instrumentation and support materials are to be removed from the ground at the end of their operable use 3.8.3 Supply of Drilling Fluid Temporary deployment of tanks (IBCs) of seawater to supply of water to drilling sites to enable drilling.

· Location(s): Heidemann Bay, West Bay, Abatus Bay, Davis Station and/or meltwater ponds. · Number of sites: Supply of water to borehole drilling program · Frequency: Collection of water daily throughout field season. IBC’s and mobile water storage tanks will be removed from the site upon completion of works. · Logistics, transport, and equipment: Ute, light truck, Hagglunds and/or helicopters will be used to deploy and recover IBCs as required and available. · Methodology: Drilling will use pooled snow-melt water (where available) or seawater sourced from the marine environment including Heidemann Bay, West Bay, Abatus Bay and with Davis Station limits. Seawater will be pumped into IBC’s and transported to the drilling locations. 3.8.4 Downhole Instrumentation Monitoring Provision of borehole monitoring instrumentation to assess ground temperatures, hydraulic conductivities, groundwater levels and soil movement to assist in engineering design.

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· Location(s): Marchants Landing, Davis Station limits, Davis Link, Adams Flat, Heidemann Valley and the Ridge Site. · Number of sites: Up to 60 locations · Frequency: Following instrumentation installation, access is required to the locations on a fortnightly basis to facilitate data transfer . · Logistics, transport, and equipment: Instrumentation to be installed as part of the borehole drilling process, refer to Section 3.8.2 · Methodology: Following the drilling of the borehole to the nominated target depth, the instrumentation will be assembled and installed within the borehole. The instrumentation will be secured in place aligned with the details provided in Section 3.5.2. Instrumentation and equipment at surface will be encased within a weatherproof case for protection and mitigate the potential for native vertebrate entrapment or impacts. · The approach to decommissioning and reinstatement of boreholes containing monitoring equipment is proposed to minimise environmental impacts, and in line with broader project remediation strategies. The potential for retaining the instrumentation may also be considered upon completion of the works, as opportunities associated with medium- and long-term monitoring may be realised. · It is proposed the boreholes containing instrumentation are be remediated upon completion of their operable use. Remediation methods may include mechanically pulling the materials from the borehole and where necessary over-drilling of the borehole, to remove all remaining instrumentation materials including PVC casings. Methods deployed during this activity will negate potential for dispersal of waste materials to the environment, namely microplastics, utilising specialise borehole decommissioning techniques in general accordance with accepted industry and environmental regulator approaches.

3.8.5 Temporary Mobile Weather Shelter Provisions Provision for temporary mobile weather shelter (MWS) or similar to provide protection for drilling personnel during drilling activities from the weather. MWS’s are proposed in addition to the existing Ridge Site emergency refuge shelters as relocation from the work site to the refuge shelters may not be feasible in adverse weather conditions.

· Location(s): All drill sites. · Number of sites: Provision of MWS at each drilling location. · Frequency: MWS to be relocated with the geotechnical drilling rig to each location. · Logistics, transport, and equipment: MWS to be transported with drilling rig and ancillary equipment for transport. · Methodology: MWS will be erected adjacent to the drilling rig as required, depend on weather conditions and duration of drilling activity 3.8.6 Hand-Augered Boreholes. Hand drilling of shallow boreholes into soil in order to sample materials and take measurements of surface soil strength properties in order to support the design of the Project.

· Location(s): Marchants Landing, Davis Station limits, Davis Link, Adams Flat, Heidemann Valley and the Ridge Site · Number of sites: Up to 50 locations · Frequency: Works to be undertaken on an ad-hoc basis throughout the season as coordinated between Field Coordinator, Station Operations Coordinator and Station Leader

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· Logistics, transport, and equipment: ATV, ute, light vehicle and Hagglund, geotechnical hand tools, hand auger equipment. · Methodology: Hand augered borehole locations will not require the formation of a working area, reducing the potential for environmental disturbance. The following activities are proposed as part of this activity: o Manual auger drilling techniques are to be adopted to facilitate the recovery of soil samples of up to 100mm diameter to a nominal depth of 3m below surface o Drilling fluids are not required for this activity o Recovered samples are to be visually logged and photographed on site and taken to Davis Station for geotechnical testing and packaging for RTA. Total volume of samples to be collected is discussed in Section 3.7.16. o Works are to be undertaken in accordance with: § Work Health and Safety requirement documented within Chapter 1 of the Operations Manual Volume 1: Station and Field which presents key WHS principles and practices that must guide all work on-station and in the field in the Antarctic and sub-Antarctic. § Environmental Protection and Management documented within Chapter 2 of the Operations Manual Volume 1: Station and Field which details environmental management issues in both station and field locations and provides information on: · first response to emergency response · environmental policy and the framework that guides operations · environmental roles and responsibilities · annual audits, exercises and stocktakes to ensure preparedness for issues. o To document evidence of visual remediation activities, pre- and post-work photographs are to be recorded to detail efforts undertaken to minimise adverse impacts associated with ground disturbance 3.8.7 Test Pit Excavation 3.8.7.1 Test Pit Excavation (Mechanical excavator ~30t). Excavation of materials within test pits up to 4.0 m deep and up to 2-meter width. Mechanical excavations will facilitate the collection of bulk soil samples and to allow visual geotechnical assessments of the exposed stratigraphy to inform infrastructure design.

· Location(s): Marchants Landing , Davis Station limits, Davis Link, Adams Flat, Heidemann Valley and the Ridge Site · Number of sites: Up to 100 locations · Frequency: Works to be undertaken on an ad-hoc basis throughout the season as coordinated between Field Coordinator, Station Operations Coordinator and Station Leader · Logistics, transport, and equipment: Ute, light vehicle and Hagglund, Station excavator. · Methodology: Following an assessment of the proposed site to identify operational and environmental sensitivities the follow methodology is proposed: o Positioning of the station excavator to commence activities o Sediment to be excavated with the excavator bucket only, with rock breaking works not required. o Visual geotechnical assessment of the test pit side walls with representative soil samples collected from the excavation spoil as required.

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o Test pits are to be backfilled with a “last out, first in approach”. Personnel will be prohibited to enter the pit if deeper than 1.0 m. o Test pits are not to remain open overnight and are to be backfilled immediately upon completion. o Works are to be undertaken in accordance with: § Work Health and Safety requirement documented within Chapter 1 of the Operations Manual Volume 1: Station and Field which presents key WHS principles and practices that must guide all work on-station and in the field in the Antarctic and sub-Antarctic. § Environmental Protection and Management documented within Chapter 2 of the Operations Manual Volume 1: Station and Field which details environmental management issues in both station and field locations and provides information on: · first response to emergency response · environmental policy and the framework that guides operations · environmental roles and responsibilities · annual audits, exercises and stocktakes to ensure preparedness for issues. o To document evidence of visual remediation activities, pre- and post-work photographs are to be recorded to detail efforts undertaken to minimise adverse impacts potentially associated with ground disturbance 3.8.7.2 Test Pit Excavation (Mechanical excavator ~3t) Excavation of materials within test pits up to approximately 3.0 m deep and up to 1 meter wide . Mechanical excavations will facilitate the collection of bulk soil samples and to allow visual geotechnical assessments of the exposed stratigraphy to inform infrastructure design.

· Location(s): Marchants Landing , Davis Station limits, Davis Link, Adams Flat, Heidemann Valley and the Ridge Site · Number of sites: Up to 50 locations · Frequency: Works to be undertaken on an ad-hoc basis throughout the season as coordinated between Field Coordinator, Station Operations Coordinator and Station Leader · Logistics, transport, and equipment: Ute, light vehicle and Hagglund, Station excavator. · Methodology: Following an assessment of the proposed site to identify operational and environmental sensitivities the follow methodology is proposed: o Positioning of the station excavator to commence activities o Sediment to be excavated with the excavator bucket only, with rock breaking works not required. o Visual geotechnical assessment of the test pit side walls with representative soil samples collected from the excavation spoil as required. o Test pits are to be backfilled with a “last out, first in approach”. Personnel will be prohibited to enter the pit if deeper than 1.0 m. o Test pits are not to remain open overnight and are to be backfilled immediately upon completion. o To document evidence of visual remediation activities, pre- and post-work photographs are to be recorded to detail efforts undertaken to minimise adverse impacts potentially associated with ground disturbance o Works are to be undertaken in accordance with:

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§ Work Health and Safety requirement documented within Chapter 1 of the Operations Manual Volume 1: Station and Field which presents key WHS principles and practices that must guide all work on-station and in the field in the Antarctic and sub-Antarctic. § Environmental Protection and Management documented within Chapter 2 of the Operations Manual Volume 1: Station and Field which details environmental management issues in both station and field locations and provides information on: · first response to emergency response · environmental policy and the framework that guides operations · environmental roles and responsibilities · annual audits, exercises and stocktakes to ensure preparedness for issues. o To document evidence of visual remediation activities, pre- and post-work photographs are to be recorded to detail efforts undertaken to minimise adverse impacts potentially associated with ground disturbance 3.8.7.3 Test Pit Excavation (Manual) Excavation of materials within test pits up to approximately 2 m deep and up to 500mm wide. Manual excavations will facilitate the collection of bulk soil samples in more inaccessible locations and to allow visual geotechnical assessments of the exposed stratigraphy to inform infrastructure design.

· Location(s): Marchants Landing, Davis Station limits, Davis Link, Adams Flat, Heidemann Valley and the Ridge Site · Number of sites: Up to 20 locations · Frequency: Works to be undertaken on an ad-hoc basis throughout the season as coordinated between Field Coordinator, Station Operations Coordinator and Station Leader · Logistics, transport, and equipment: Ute, light vehicle and Hagglund, hand tools · Methodology: Following an assessment of the proposed site to identify operational and environmental sensitivities the follow methodology is proposed: o Excavation of the test pit using hand tools only. o Visual geotechnical assessment of the test pit side walls with representative soil samples collected from the excavation spoil as required. o Test pits are to be backfilled with a “last out, first in approach”. Personnel will be prohibited to enter the pit if deeper than 1.0 m. o Test pits are not to remain open overnight and are to be backfilled immediately upon completion. o To document evidence of visual remediation activities, pre- and post-work photographs are to be recorded to detail efforts undertaken to minimise adverse impacts potentially associated with ground disturbance o Works are to be undertaken in accordance with: § Work Health and Safety requirement documented within Chapter 1 of the Operations Manual Volume 1: Station and Field which presents key WHS principles and practices that must guide all work on-station and in the field in the Antarctic and sub-Antarctic. § Environmental Protection and Management documented within Chapter 2 of the Operations Manual Volume 1: Station and Field which details

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environmental management issues in both station and field locations and provides information on: · first response to emergency response · environmental policy and the framework that guides operations · environmental roles and responsibilities · annual audits, exercises and stocktakes to ensure preparedness for issues. o To document evidence of visual remediation activities, pre- and post-work photographs are to be recorded to detail efforts undertaken to minimise adverse impacts potentially associated with ground disturbance 3.8.8 Dynamic Cone Penetrometer Testing. The site geotechnical engineer to undertake Dynamic Cone Penetrometer testing to manually assess the in-situ strength profile of the existing ground conditions. Information to be fed into the Project design activities in order to develop a geotechnical ground model.

· Location(s): Marchants Landing, Davis Station limits, Davis Link, Adams Flat, Heidemann Valley and the Ridge Site · Number of sites: Up to 170 locations (one at each test pit location) · Frequency: Works to be undertaken on an ad-hoc basis throughout the season as coordinated between Field Coordinator, Station Operations Coordinator and Station Leader · Logistics, transport, and equipment: ATV, ute, light vehicle and Hagglund and helicopter as required. Handheld geotechnical measurement equipment comprising Dynamic Cone Penetrometer, shovel, and trowel. · Methodology: Dynamic Cone Penetrometer testing will not require the formation of a working area, reducing the potential for environmental disturbance. The following activities are proposed as part of this activity: o Dynamic Cone Penetrometer testing, comprising the measurement of cone penetration into the subgrade based on quantum of “weigh-drops” o Recovery of all instrumentation from the subgrade upon completion of testing 3.8.9 Geological Mapping. Geotechnical engineer to visually inspect and geologically map rock outcrops, manually test bedrock strength for geotechnical analyses, geomorphological features and collect representative samples for rock strength analysis at station or to be prepared for analysis following RTA.

· Location(s): Marchants Landing, Davis Station limits, Davis Link, Adams Flat, Heidemann Valley and the Ridge Site · Number of sites: As required to sufficiently characterise the areas of geotechnical interest. · Frequency: Works to be undertaken on an ad-hoc basis throughout the season as coordinated between Field Coordinator, Station Operations Coordinator and Station Leader · Logistics, transport, and equipment: ATV, ute, light vehicle and Hagglund and helicopter as required. Handheld geological measurement equipment including compass clinometer, geological pick, cameras , shovel, trowel · Methodology: Walking over terrain to map physical geotechnical and geological conditions and assess in situ geological conditions. Collection of representative samples for rock strength analysis at station or to be prepared for analysis following RTA.

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3.8.10 Geophysical Survey The field team proposes to undertake geophysical survey to provide a more comprehensive, 3- dimensional geotechnical engineering assessment of areas within the project site to maximise program opportunities and minimise potential environmental impacts during and following Aerodrome construction.

· Location(s): Marchants Landing, Davis Station limits, Davis Link, Adams Flat, Ridge Site and Heidemann Valley · Number of sites: Number of individual transects to be determined following a review of the outcomes of the 2021 Winter drilling program. Allowance of 20,000 linear meters of geophysical survey to be made for each proposed survey technique. · Frequency: Works to be undertaken on an ad-hoc basis throughout the season as coordinated between Field Coordinator, Station Operations Coordinator and Station Leader · Logistics, transport, and equipment: Ute, light vehicle, light truck, Hagglunds or Helicopter support where practical to transport and relocate survey equipment. · Methodology: Alignment of survey transects are to be determined following a review of the collected geotechnical drilling and excavation information and review of environmental sensitivities. Once transects have been nominated, a grid survey is likely to be proposed, with survey transect spacings ranging from 25m to 50m centres depending on the anticipated subgrade conditions and the potential impacts to engineering design. o General access to the proposed geophysical transect locations is to be via the temporary vehicle access tracks. Where transects are located away from the access track, equipment will be manually hauled to the survey location o Seismic arrays consisting of geophones and associated cabling is to be laid along the nominated transects connected to datalogging equipment. o A seismic signal is to be generated by hitting a baseplate with a falling weight. Returned signal times are recorded and processed to interpret subgrade velocities and subsequently material conditions. o Works are to be undertaken in accordance with the following: § Work Health and Safety requirement documented within Chapter 1 of the Operations Manual Volume 1: Station and Field which presents key WHS principles and practices that must guide all work on-station and in the field in the Antarctic and sub-Antarctic. § Environmental Protection and Management documented within Chapter 2 of the Operations Manual Volume 1: Station and Field which details environmental management issues in both station and field locations and provides information on: · first response to emergency response · environmental policy and the framework that guides operations · environmental roles and responsibilities · annual audits, exercises and stocktakes to ensure preparedness for issues. o To document evidence of visual remediation activities, pre- and post-work photographs are to be recorded to detail efforts undertaken to minimise adverse impacts potentially associated with ground disturbance

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3.8.11 Re-establishment of Existing and/or New Temporary Access Tracks. To enable access to sites of geotechnical interest to inform Project design, tracks and disturbed ground from historical field seasons are to be reused where practical. Alignments of historical access tracks are to be visually assessed on ground by those actively involved in the previous project phases.

· Location(s): Marchants Landing, Davis Station limits, Davis Link, Adams Flat, Heidemann Valley and the Ridge Site · Number of sites: Lengths of new or re-established access tracks are dependent on the project requirements and are to be minimised to meet project goals. It is proposed potential new temporary access tracks, will less than 7500m in total length · Frequency: Works to be undertaken on an ad-hoc basis throughout the season as coordinated between Field Coordinator, Station Operations Coordinator and Station Leader. Track use to vary depending on work site location and duration of activity. · Logistics, transport, and equipment: Excavator (self-drive), personnel movements by ATV, ute, light vehicle and Hagglund. · Methodology: Following an assessment of the proposed alignment to identify operational and environmental sensitivities the follow methodology is proposed: o Clearance of surface obstructions to facilitate vehicle access o Materials moved to accommodate access track formation, is proposed to be placed to the side of the track to facilitate reinstatement efforts o To document evidence of visual remediation activities, pre- and post-work photographs are to be recorded to detail efforts undertaken to minimise adverse impacts potentially associated with ground disturbance o Works are to be undertaken in accordance with: § Work Health and Safety requirement documented within Chapter 1 of the Operations Manual Volume 1: Station and Field which presents key WHS principles and practices that must guide all work on-station and in the field in the Antarctic and sub-Antarctic. § Environmental Protection and Management documented within Chapter 2 of the Operations Manual Volume 1: Station and Field which details environmental management issues in both station and field locations and provides information on: · first response to emergency response · environmental policy and the framework that guides operations · environmental roles and responsibilities · annual audits, exercises and stocktakes to ensure preparedness for issues. o To document evidence of visual remediation activities, pre- and post-work photographs are to be recorded to detail efforts undertaken to minimise adverse impacts potentially associated with ground disturbance 3.8.12 Near-surface Water Flow Monitoring. Measurements of near-surface water flows are proposed to facilitate collection of data to assess rates of water movement to inform project design.

· Location(s): Marchants Landing, Davis Station limits, Davis Link, Adams Flat, Heidemann Valley and the Ridge Site · Number of sites: Up to 15 locations in total

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· Frequency: Works to be undertaken on an ad-hoc basis throughout the season as coordinated between Field Coordinator, Station Operations Coordinator and Station Leader. Flow measurements to be undertaken on a bi-weekly basis upon installation · Logistics, transport, and equipment: ATV, ute, light vehicle Hagglund as required, V-notch weirs (composed of wood / metal formwork), impermeable sheeting to prevent lateral water flow migration, excavation equipment (manual or excavator) and handheld tools. · Methodology: Following an assessment of the proposed site to identify operational and environmental sensitivities the follow methodology is proposed: o Excavation of temporary holding / discharge basin upstream of the V-notch weir, up to 1.5m deep and 3m in width lined with impermeable sheeting o Installation of V-notch weir, comprising a sheet of plywood with “V-notch” cut to facilitate water flow o Requirement for weir to be “pinned” to ensure structural form and integrity over the field season. o Works are to be undertaken in accordance with the following: § Work Health and Safety requirement documented within Chapter 1 of the Operations Manual Volume 1: Station and Field which presents key WHS principles and practices that must guide all work on-station and in the field in the Antarctic and sub-Antarctic. § Environmental Protection and Management documented within Chapter 2 of the Operations Manual Volume 1: Station and Field which details environmental management issues in both station and field locations and provides information on: · first response to emergency response · environmental policy and the framework that guides operations · environmental roles and responsibilities · annual audits, exercises and stocktakes to ensure preparedness for issues. o To document evidence of visual remediation activities, pre- and post-work photographs are to be recorded to detail efforts undertaken to minimise adverse impacts potentially associated with ground disturbance 3.8.13 Lake and Waterbody Level Monitoring. Measurement of seasonal Lake and waterbody levels to collect data on water recharge and discharge is proposed in the vicinity of the proposed project infrastructure to assist in the ongoing project development.

· Location(s): Marchants Landing, Davis Station limits, Davis Link, Adams Flat, Heidemann Valley and the Ridge Site · Number of sites: Up to 20 locations · Frequency: Installation proposed early in the field season program to facilitate assessment of seasonal variations and visually monitored weekly thereafter · Logistics, transport, and equipment: ATV, ute, light vehicle Hagglund, level gauge marker, stake, manual hand tools · Methodology: o Equipment is to be inspected and cleaned prior to installation to negate the potential for contamination of the lake / waterbody. o Stake to be driven into lake/water body bed in order on which to mount the water level gauge. MARCH 2021

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o Visual monitoring on lake / waterbody levels from shore positions on a weekly basis throughout the field season 3.8.14 Survey 3.8.14.1 Terrestrial Survey Acquisition of terrestrial topographic and feature survey data to facilitate the ongoing project design

· Location(s): Marchants Landing, Davis Station limits, Davis Link, Adams Flat, Heidemann Valley and the Ridge Site . · Number of sites: Project Site-wide · Frequency: Daily throughout the 2021/2022 Summer field season · Logistics, transport, and equipment: ATV, ute, light vehicle Hagglund or helicopter support (depending on site and resources), Real Time Kinematic (RTK) GPS, terrestrial laser scanner and RPA (drone) and survey benchmarks (site markers) to facilitate survey set out · Methodology: o Survey equipment to be carried by Surveyor/ Surveyor's Assistant to establish benchmarks to correlate project wide survey information. o Terrestrial laser scanner to be mounted on tripod for stability to acquire point cloud survey data o Multiple positions of terrestrial laser scanner required to overlap data points to facilitate processing of data. o Where surface conditions preclude the use of the terrestrial scanning equipment, staff mounted RTK equipment is proposed to be adopted requiring a grid-based survey approach throughout the nominated extents. o To acquire broader photogrammetry survey information, an RPA (drone) is proposed to be utilised. o Works are to be undertaken in accordance with the following: § Work Health and Safety requirement documented within Chapter 1 of the Operations Manual Volume 1: Station and Field which presents key WHS principles and practices that must guide all work on-station and in the field in the Antarctic and sub-Antarctic. § Environmental Protection and Management documented within Chapter 2 of the Operations Manual Volume 1: Station and Field which details environmental management issues in both station and field locations and provides information on: · first response to emergency response · environmental policy and the framework that guides operations · environmental roles and responsibilities · annual audits, exercises and stocktakes to ensure preparedness for issues. § Aviation Standard Operating Procedures documented within Volume 5 of the Operations Manual which details all aerial operations using unmanned aerial systems (UAS) will be conducted in accordance with the conditions and limitations placed on the Remotely Piloted Aircraft Operator’s Certificate (ReOC) and/or the conditions and limitations set out by the Department of Agriculture, Water and Environment and the Australian Antarctic Division.

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3.8.14.2 Hydrographic Survey Acquisition of offshore, nearshore and waterbody hydrographic survey information on which the ongoing project engineering design can be established.

· Location(s): Coastal areas surrounding Marchants Landing, Davis Station, Davis Link, Adams Flat , Ridge Site and within existing lakes and ephemeral waterbodies · Number of sites: Various · Frequency: Daily throughout the 2021/2022 Summer field season · Logistics, transport, and equipment: ATV, ute, light vehicle, IRB, Hagglund or helicopter support (depending on site and resources), Real Time Kinematic (RTK) GPS and single beam / multibeam survey equipment. · Methodology: o Following safety inductions and briefings, hydrographic survey equipment comprising single/multibeam echo sounder, is to be mounted to the IRB o The IRB will follow a predestined grid transect path collecting hydrographic data o Data will be recoded on site and transferred and processed upon return to shore. o IRB’s operations noting the equipment, transport, operation, and environmental requirements are to be accordance with AAD’s Watercraft Procedures (Chapter 7.1 Watercraft Standard Operating Procedures). 3.8.15 Samples Collection Selected samples collected through excavation, drilling, hand sampling, and augered to be transported to Australia for testing and analyses. This is to provide essential additional geotechnical data to provide essential baseline information for ongoing design works.

· Location(s): Marchants Landing, Davis Station limits, Davis Link, Adams Flat, Heidemann Valley and the Ridge Site · Number of sites: As presented in Section 3.7.2 and 3.7.7 · Frequency: Samples to be collected as part of the 2021-2022 field season activities. Opportunities for RTA of samples to be assessed based on operational opportunities · Logistics, transport, and equipment: Samples to be prepared for transport and loaded into refrigerated and unrefrigerated containers on Station as required. Containers to be registered and processed as part of Station logistics procedures. · Methodology: A total of up to 31,500 kg of soil and rock samples to be removed acquired from the geotechnical site investigation program, comprising: · Geotechnical soil bulk samples x 140 @ up to 25 kg (3,500 kg) · Geotechnical hand specimen rock samples x 100 @ up to 10 kg (up to 1,000 kg) · Geotechnical soil and rock core samples (up to 3,300 linear meters) – up to 27,000kg · Ground and surface water samples up to 250L in total

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46 INITIAL ENVIRONMENTAL EVAULATION 2021-22 FIELD SEASON 4 Alternatives to the Proposed Activity Alternatives to entire scope of the proposed 2020-21 field season activities have been considered and described below. In addition, a detailed description of the alternatives to each scope element within the proposed 2020-21 field program is provided in Appendix 2. 4.1 Do Nothing Consideration has been given to the option of not undertaking the proposed geotechnical field activities. Alternatives to the project as a whole would be to perform further desk-top studies of the Vestfold Hills to support the construction planning and engineering design of the project and ancillary infrastructure and future environmental impact assessments (as was done in the 1990’s), however this approach presents significant risks to the environment and success of the project objectives.

In addition to inadequate information being made available to the AAD and delivery partners on which to plan and design the construction, operation, and maintenance of the project, it would result in insufficient information with which to adequately assess potential environmental impacts. 4.2 Alternate Locations and Timing The project has considered alternative locations for the proposed field activities, however the locations that have been selected are the most appropriate areas to undertake the required geotechnical assessments, to provide the information considered necessary to inform construction planning and engineering design, and further articulate project constraints and opportunities to stakeholders.

The primary potential adverse impacts posed by the fieldworks are to ground and wildlife disturbance. Consideration as to the sequencing of works throughout the season will be undertaken to minimise the impact for ground disturbance, and to collaborate with the relevant environmental subject matter experts on station to reduce the potential for environmental impact to as low as reasonably practical, as discussed in Section 3.6.1.1. 4.3 Alternate Methods and Technologies Alternative methods and technologies have been considered for each aspect of the proposed activity. The Project has selected the methods and technologies to be used, with the view they will maximise efficiencies, reducing the time required in the field, and minimise impact on the environment.

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47 INITIAL ENVIRONMENTAL EVAULATION 2021-22 FIELD SEASON 5 Description of the Environment 5.1 Physical Characteristics of the Vestfold Hills The Vestfold Hills are a roughly triangular ice-free area with an area of approximately 400 km2. It is bounded to the east by the relatively inactive Antarctic ice cap, to the south by the active Sørsdal Glacier, and to the west by the Southern Ocean. The landscape has low relief to the west and north, steadily becoming more rugged to the south and east (i.e. closer to the ice margins). The highest exposed point approaches 160 m above sea level. The area is characterised by the presence of hundreds of lakes and ponds, ranging in salinity from amongst the most saline to the freshest in the world. Plant life is limited to algae, lichens and mosses that are more common closer to the ice margins, with higher animals limited to non-resident birds and seals. A wide range of microscopic invertebrates, however, inhabit the lakes and some terrestrial habitats.

The bedrock geology of the Vestfold hills consists of a varied assemblage of gneissic lithologies derived from both igneous and sedimentary sources that have subsequently been metamorphosed at high temperature and pressure (Clark et al., 2012). The four main mapped units occur in repeated, narrow east-west-aligned bands that extend across the area. A swarm of mafic dykes, likely to have been emplaced during separate events in the late Archaean and Proterozoic, are obvious features of the landscape. Many of these dykes are sub-parallel and occur along three major alignments (Figure 11).

Figure 11 – Indicative Site Context - The Vestfold Hills showing lakes and dyke swarms (Photo from AAD Image Library).

From 40 million years (Ma) ago Antarctica became progressively more strongly glaciated and since circa 23 Ma has been nearly completely glaciated. During this period Antarctica separated from the other Gondwanan continents. Information about the history of the Vestfold Hills after the formation of the bedrock and prior to the Last Glacial Maximum (LGM, 18-20 000 years before present (BP)) is scarce, though some conclusions are drawn in the discussion below. The only identified feature

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dating from this period in the Vestfold Hills occurs at Marine Plain, where a thin layer of Quaternary marine sediment overlies diatom-rich marine sediments of Pliocene (ca 4 Ma) age (Quilty et al., 2000). These sediments were deposited under near coastal conditions and contain fossil cetaceans that are globally important. This site is central to a major scientific debate on the nature of the Antarctic continent at the time.

It was long thought that the Vestfold Hills were covered by a thick ice cover (of the order of 1000 m) at the LGM, but in recent years a series of observations has led to the conclusion that at least some of the Vestfold Hills remained ice-free. The observations include the geology and geomorphology of Heidemann Valley; weathering intensity, in particular in the north-western areas of the hills; evidence for the continued existence of lakes through the LGM; and cosmogenic exposure dates for glacial erratics. See Gibson et al. (2009) for further discussions.

Global sea level rise since the LGM resulting from ice melt has totalled 120 m, and it might be concluded that the LGM shoreline of the Vestfold Hills was significantly to the seaward of that of the present day. The situation, however, has not been that simple, as the regional removal of ice has resulted in a concomitant isostatic rebound of the land surface. There was a reasonable concordance between the rate of sea level rise and isostatic rebound throughout the Holocene. Local sea level increased to a marine highstand of about 9.5 m above present sea level roughly 6000 yr. BP, after which sea level is thought to have declined more or less linearly to the present (Zwartz et al., 1998). The highstand is manifested by the existence of extensive marine terraces and beach deposits containing abundant marine fossils, and the evidence from sediments of marine phases following freshwater phases in lakes with sills to the ocean lower than 9.5 m. There is no information about the timing or extent of any marine lowstand.

The result of this marine highstand is that most of the Vestfold Hills with an elevation of less than 9.5 m has been directly affected by salt: the lakes in this region are saline and contain marine- derived organisms, the soils contain significant amounts of salt, salt-induced weathering is commonplace, and salt-sensitive flora, including lichens and mosses, are sparse or absent.

As the isolated marine system evaporated the sills between basins became exposed, and separate lakes were formed. At least eleven major lakes and many minor lakes were formed that now have salinities well above that of seawater. Deep Lake, the most saline of the lakes, has a depth of 34 m, and a surface level of 50 m beneath sea level. This indicates a total basin depth of 84 m, the deepest in the system.

The biota of the lakes of the Vestfold Hills is in part, reasonably understood. The bacteria, archaea, plants, and animals occur in two distinct habitats within the lakes: the water column and the microbial mats that cover the base of the lakes. Microbial mats are a melange of bacteria, algae and mosses that supports a grazing community of nematodes, rotifers, tardigrades, and other invertebrates. In comparison, the biota of the water columns have been studied in greater detail, due in part being of particular scientific interest to advance studies of meromictic and hypersaline lakes, and also through being considerably simpler in complexity to the broader geography.

The basic characteristics of the bacterial and archaeal flora of the water columns of some lakes has been investigated quite thoroughly using traditional methods, in part due to the distribution of these species in the unique hypersaline or meromictic lakes in the area. More recently these organisms have been studied in detail using modern molecular genetic approaches (for a review see Cavicchioli, 2015). In contrast, the prokaryotes (mainly cyanobacteria) of the microbial mat systems are less well known, but some molecular genetic work has been undertaken (e.g. Taton et al, 2006).

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5.1.1 Biota A biogeographic analysis divides the continent into 16 distinct environments identified as ‘Antarctic Conservation Biogeographic Regions’ (Terauds et al. 2012; Terauds and Lee 2016). The Vestfold Hills falls within the region identified as ‘East Antarctic.’

5.1.2 Birds Bird species of the Vestfold Hills include Adelie Penguins (Pygoscelis adeliae), Emperor Penguins (Aptenodytes forsteri), Cape Petrels (Daption capense), Southern Giant Petrels (Macronectes giganteus), South Polar Skuas (Stercorarius maccormicki), Snow Petrels (Pagodroma nivea), and Wilson’s Storm Petrels (Oceanites oceanicus). Adelie penguin rookeries are known in offshore islands, while Emperor Penguins have only ever been observed transiting through the hills using occasional moulting sites. Some Snow Petrels and Wilson’s Storm Petrel, and possibly South Polar Skuas may be breeding in the areas where geotechnical investigations are taking place. The nearest breeding colonies to the investigation area for these three species occur on Gardner and Lugg Islands.

The sea bird breeding season occurs from October to March and coincides with the timing of the 2021/2022 Summer season investigations. Species breed at the ground surface or in sub-surface rock cavities and cracks. Snow Petrel and Wilson’s Storm Petrel nests can be difficult to locate and observe due to their cryptic sub- surface nesting. Informal observations indicate that nests are generally located in crevices or under overhanging outcrops or boulders on ridges in close proximity to the coastline. For example, it is commonly known that Snow Petrels are nesting in the vicinity of the quarry, and Wilson’s Storm Petrel nests have been found adjacent to the coast at Adams Flat. Nests along the valley floor of Heidemann Valley have not been identified to date, and the likelihood of their existence is not expected to be high, however they cannot be omitted.

Prior to works commencing on site, the project field team will undertake seabird habitation awareness training facilitate by the DAP Environmental Officer- Wildlife , in addition to an on-ground familiarisation exercise to provide practical based training. The DAP Environmental Officer-Wildlife will be on Station during the 2021 winter field season and will be accessible to provide support and guidance as required. Noting the project geotechnical drilling works are to be primarily undertaken outside of the seabird breeding season of October to March, visual inspections will be made prior to works commencing on site to assess potential avian impacts.

There is anecdotal evidence that these sub-surface breeders are more active in flying around their nest sites during the ‘night’ hours, so they may appear to be less abundant from ‘daytime ‘ observations. Although surface-breeders, South Polar Skuas and Southern Giant Petrels, can also be difficult to see and find because their plumage camouflages them well from the rock background.

Eight bird populations/sites in the Vestfold Hills have been declared Important Bird Areas meaning they are considered to be of international conservation significance. Three of these areas are within 5 km of the investigation area, with seven nesting areas identified on the Ridge Site, however due to the short-term, small-scale field activities, they are proposed to not be impacted by project activities over the 2021-2022 seasons. The DAP Environmental Officer- Wildlife is to be engaged to support avian habitat inspections in the vicinity of the nominated areas of sensitivity as required.

Other bird populations/sites have significance based on other criteria. Hawker Island, 7 km south- west of Davis, is the breeding habitat of the southernmost colony of Southern Giant Petrels nesting on continental Antarctica and has been designated a protected area (ASPA #167). These birds are

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especially sensitive to disturbance at the nest. Works are not proposed on or in the vicinity of Hawker Island and as a result adverse impacts are not anticipated.

5.1.3 Seals Four seal species are found locally – Southern Elephant Seals (Mirounga leonina) which is a summer visitor, Weddell Seals (Leptonychotes weddelli) which breed in Tryne and Long Fjords, Crabeater Seals (Lobodon carcinophagus) and Leopard Seals (Hydrurga leptonyx) which are a summer predator. Southern Elephant Seal haul out areas are known at the station itself and Old Wallow, with occasional observations around the coast towards Law Cairn and other sites, but these are sporadic and unpredictable. Weddell seals are common in Long Fjord during the summer (in particular at Weddell Arm and Shirokaya Bay), and Leopard Seals have been observed throughout the region, and in particular near penguin colonies.

5.1.4 Terrestrial Microbiota The Vestfold Hills belong to a biogeographic region of high invertebrate diversity including mites, tardigrades, nemotodes and rotifers.

Microbial communities include cyanobacteria, bacteria, protozoa, edaphic algae, and terrestrial algae such as endolithic, hypolithic and sublithic types.

5.1.5 Flora Antarctica’s vegetation is sparse to the point of rareness, yet the flora of the Vestfold Hills comprises at least six moss and 23 lichen species (Seppelt & Broady, 1988). The lichens and mosses are distributed chiefly in the eastern or inland sector, their distribution patterns reflecting the availability of drift snow, time since exposure of the substrate from the ice plateau, time since the last glaciation, elevation, and proximity to saline waters. Mosses are noticeably absent in the western part of the Vestfold Hills (Pickard, 1986).

5.1.6 Marine Benthic (Seabed) Biota The first significant marine biological benthic surveys were done in 1982 by Burton, Kirkwood and Tucker and consisted of repeated monthly sampling over a full year at three sites off Davis Station (Tucker & Burton 1988), and an additional one-off but extensive survey of the middle section of Ellis Fjord (Kirkwood & Burton 1988). The survey of Ellis fjord revealed a previously unknown major biogenic reef, consisting of calcareous tubes built by polychaete worms, which forms one of the largest known tubeworm reefs in the world, stretching for over 8 km. A description of the fish communities found in the nearshore region was published by Williams (1988), based on collections made between 1978 and 1984.

A subsequent survey was undertaken in 2010, as part of an AAD-led environmental impact survey of the Davis Station wastewater outfall by Stark and co-workers. This included a survey of 30 sites ranging from the mouth of Long Fjord in the north, extensive sampling offshore from Davis Station within a 2 km radius, and further sampling south including the mouth of Ellis Fjord and as far south as the mouth of Crooked Fjord (Stark et al., 2016). This survey revealed a previously unknown diversity of benthic habitats and biological communities. Further work remains to be done to publish these results.

The project also included an investigation into the complexity and structure of the inshore marine food web (Gillies et al., 2013). The impact assessment was complemented by a hydroacoustic bathymetric survey done by the Royal Australian Navy and Geoscience Australia, which resulted in the development of geomorphological (O’Brien et al., 2015) and benthic habitat maps (Smith et al.,

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2015). Further works in 2019/2020 included a marine and benthic program incorporating ROV video survey, sediment grab samples and water sampling.

Several highly rare marine habitats exist in the Vestfold Hills region. These include:

· Heidemann Bay: At the head of the bay is an area of intertidal mud flat, a habitat which is extremely rare in Antarctica and has not been previously described. No studies have ever been done of this site. The site may be up to 500 m wide and 100 m long when exposed at low tide. The remainder of the bay is very shallow (1 – 6 m deep) and consists of sandy sediments and boulders, with a diverse community of macroalgae (seaweed) and associated invertebrates. One site was surveyed in the outer area of the bay in 2010 and several sites just outside the bay in the vicinity of Marchants Landing. · Long Fjord (and Ellis and crooked Fjords): Several subtidal sites have been surveyed in the vicinity of the mouth of Long Fjord and between Plough Island and the mainland. Fjords are very rare in Antarctica and mainly found on the Antarctic Peninsula, but the Vestfold Hills have a unique concentration of fjords. Surveys done in 2010 around Long Fjord revealed a remarkable degree of biodiversity and habitat heterogeneity. Every site surveyed in the area had different biological communities, even though the physical characteristics appeared relatively similar. Polychaete reefs were found in the mouth of Long Fjord and it is suspected that they may also be very extensive, but they have not been surveyed. Limited photoquadrat surveys revealed a very high degree of biodiversity associated with the polychaete reefs, with a host of different marine invertebrates living in and on it, as well as many fish.

5.1.7 Meteorology and Climate Davis has a relatively mild climate and is known as the 'Riviera of the South'. The 400 km2 of exposed undulating rocks dampens the katabatic winds off the ice sheet, resulting in an average yearly wind speed of around 20 km/h. Summer temperatures can reach a maximum of +13°C, the winter temperature can reach - 40°C with mean maximum temperatures averaging at +3.2°C in summer and -14.0°C in winter, and mean minimum temperatures averaging -1.2°C in summer and - 20.8°C in winter (averages taken from all years of occupation from 1957 to 2016).

The predominant wind direction is from the northeast and is rarely strong, although sudden storms can occur with gusts in excess of 200 km/hr.

Precipitation is usually in the form of snow, although rain has been experienced. Snowfall is up to 50 mm/yr (average being 33 mm/yr) and can be a blend of snow blown off the ice sheet, or locally falling. Snow drifts are common in the lea of rocky ridges and station buildings.

In the Davis summer, the sun stays above the horizon for most of December and January and in winter it stays below the horizon for about two months from early June. During the winter, the 'day' is made up of one to two hours of twilight.

5.1.8 Human Presence Davis Station was established as a scientific research base in 1957 and has been occupied continuously since then except for a 4-year period in the 1960s. Davis consists of more than 80 structures; 60 of which stand on cement foundations poured on site. Others have pre-cast foundations or are portable. Most of the buildings are serviced by above-ground reticulated water, power, and sewerage systems.

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A quarry face, 8-10 m high, ~250 m long, and 85 m wide, lies ~800 m south-east of the centre of the station. The quarry has been used (mostly between October and March) as a source of gravel for station-based projects.

There are two radar antenna installations near Heidemann Bay beach – a square array of 144 VHF antennae for sensing mesosphere-stratosphere-troposphere wind activity, and a star configuration of five antennae for a meteor detection wind radar. The arrays are < 3 m tall.

Evidence of human activity also exists in the form of automatic weather stations, caches, signage, route markers, temporary access tracks, fencing, scientific markers, navigation beacons, cairns, plaques, and crosses.

Throughout the valley areas to the northeast and north of the station there is widespread evidence of human presence in the form of old caterpillar tracks, bulldozed scrapings, and shallow pit workings. These were formed during the early 1980s during geotechnical investigations in support of aviation landing areas and have not been remediated.

5.1.9 Scientific Values Ice free areas in Antarctica are scarce. Accordingly, their scientific and research values are immense. The Vestfold Hills region’s features are individually remarkable and highly significant in their aggregation as components of a habitat island and small ecosystem.

The variety and concentration of lakes found in the Vestfold Hills is the greatest on the continent and of worldwide interest (Marchant et al., 2002).

High latitude lakes are key monitoring sites for the early detection of global change effects (Vincent, 1997). The Vestfold Hills have been identified as an ecosystem positioned to contribute to a network of ecosystems to test climate change predictions; the AAD’s research community is working towards developing such an observing system (AAD, 2015).

Antarctic lakes have long been identified as model systems for understanding global questions about biodiversity, its spread and its ubiquity or rarity, across the planet. Metagenomic studies provide insight into how these types of ecosystems are structured and function (Refer to Pyper, 2013).

The region’s meromictic lakes are a particularly rich area for bacteriological studies (Marchant et al., 2002).

Research into extreme environments like Deep Lake could provide insights of relevance to astrobiology. Archaea known as ‘methanogens’ growing devoid of oxygen and under cold conditions in Ace Lake in the Vestfold Hills may share properties with the kind of life that could live on Mars.

Enzymes from both haloarchaea and methanogens could be valuable for use in biosensors to assess whether biological reactions are occurring on other planets.

Some 98% of Antarctica’s rock is buried by ice that in some places is kilometres deep; the Vestfold Hills are one of the few areas of exposed rock available for geological research. As such, the Vestfold Hills are more accessible than many other exposures of geological interest (Collerson et al. 2002).

For example, the Vestfold Hills are emerging as a significant site for studies of the Late Neogene of the Antarctic margin (Colhoun et al., 2010). They also contain fossils of whales and dolphins, filling a 40-million-year gap in records of vertebrates in Antarctica. One site (Marine Plain, an ASPA of 23 km2, 5-12 km from Davis) has been described of ‘exceptional scientific interest’ because of its

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relevance to the palaeoecological and paleoclimatic record of Antarctica: ‘They are the only known source of vertebrate fossils since Antarctica first became glaciated some 34 million years ago’ (Stillwell and Long, 2011). Marine Plain is a world class example of a fossil site, providing rare insight into the evolution of marine mammals and the polar paleoclimatic conditions during the Pliocene. Its vertebrate fossil fauna include ‘Australodelphis mirus, the first higher vertebrate named from the Oligocene-Pleistocene interval on land in Antarctica, and the first cetacean fossil from the polar margin of circum-Antarctic Southern Ocean that post-dates the break-up of Gondwana. It has also revealed four other species of cetaceans; a species of fish; and a diverse invertebrate fauna comprising molluscs, gastropods, marine diatoms and the first Pliocene decapod crustacean from Antarctica.

Terrestrial coastal habitats, of which the Vestfold Hills are one, are a source of endemic microbes that may be a potential source of novel biotechnologically important compounds (Hughes et al., 2015).

5.1.10 Wilderness and Aesthetic Values The region’s physical attributes include the number, patterning and diversity of shapes and intensity of colouring of its lakes; the presence and contrast of the plateau; the formation and retreat of sea ice; the clarity of the near-shore water and the Hills’ intersecting fjords; the patterns of dark stripes and criss-crossing of black dolerite against a paler brown base; the abundance of iconic species of wildlife; and the variety, texture and colour of individual rocks. These features variously contribute to senses of beauty, solitude, remoteness, discovery, and scale. The qualities of the Vestfold Hills’ environment, in totality, are not reproduced elsewhere.

If conducted in the manner described in this IEE, the proposed field program will have minimal impact on the region’s aesthetic and physical attributes.

5.1.11 Cultural Heritage Values and Historic Importance The Vestfold Hills have several structures that have been ascribed as having exceptional and considerable heritage value when assessed against domestic (Australian Government) criteria.

Two sites of significance to Australia are also internationally recognised – Wilkins’ Walkabout Rocks cairn and Mikkelsen’s cairn have been declared historic sites/monuments within the Antarctic Treaty System (#6 and #72).

Within the investigation area lies Law Cairn, about 5 km north of Davis on a rocky ridge overlooking Adams Flat. It signifies the first presence of the Australian National Antarctic Research Expeditions (ANARE), led by Dr. Phillip Law.

In 2017-18 the Project discovered artefacts including a wooden crate lid, soap, wire with evidence of a tent site and vehicle tracks. They were found on the north-eastern shore of Camp Lake, on Broad Peninsula, Vestfold Hills. They are likely evidence of Phillip Law’s occupation of a camp site in January 1955.

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5.1.12 Location of Main Wildlife Concentrations

PROJECT EXTENTS

Figure 12 - Vestfold Hills and Davis - Main Wildlife Concentrations

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6 Impact Assessment and Mitigation Measures 6.1 Methods and Data Used in Impact Assessment The methods used to assess and manage the potential impacts associated with the proposed field activities are based on observations from past activities and previous experience of subject matter experts in relevant fields of science from within, and outside the AAD Science Branch. The impacts and mitigations described have also been greatly informed by the DAP Team, who have successfully scoped, led, and delivered geotechnical field investigation programs over recent years.

For geotechnical related activities, previous experience and lessons learned through AAD Projects 3338, 3372, and 5097 have been referenced. The visual remediation techniques proposed and executed during these seasons haven been demonstrated to be effective to remediate ground disturbance. A photographic survey presented in an internal field report to record ground recovery twelve months after ground disturbance, was performed by the tasks Field Co-ordinator, Dr Barbara Frankel (geologist) in 2013-14, which documented that negligible visual evidence was found of activity at sites of works (refer also to Frankel, 2014).

There is a high level of certainty in understanding the impacts of the proposed 2021-2022 field activities on the environment, as they have all been undertaken in a form under AAD Project 5097 and 3338 over previous field seasons. 6.2 Potential Impacts and Mitigation Measures The following predicted impacts are based upon the Project’s and the AAD’s experience of conducting geotechnical field work activities at Davis over previous field seasons. Aligned with the approach adopted for those activities, the mitigation measures proposed have been demonstrated to mitigate and reduce the impact the activities may have on the environment.

The activities of this project do not introduce unknown or untested methods of works to those previously undertaken and reported on by the project. The proposed mitigation methods are reflective of those previously approved as part of historical IEE submissions and are deemed suitable and applicable, having been and observed on site by TET representatives during the 2018-2019 field season.

The impacts and mitigations measures for each aspect of the proposed activities are listed in the Tables provided in Appendix 1 and 2 with the overall impacts and mitigation measures described below:

6.2.1 Impacts on Ice and/or Ice-free Areas 6.2.1.1 Geotechnical Drilling, Test Pit Excavation and Access Track Use 6.2.1.1.1 Impacts

One of the greatest potential environmental impacts, is anticipated to be ground disturbance induced by borehole drilling, test pit excavation and temporary track use activities. Such impacts are proposed to be visible during the season, however mitigation measures have been proposed, which include the visual remediation of sites at the end of the field season to reduce the level of visual impact.

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Photographic evidence of pre- and post-work site conditions are to be documented for records. Consideration as to potential impacts associated with to native wildlife by ground disturbance have been considered, with mitigation measures discussed in the following sections.

6.2.1.1.2 Mitigation Measures

The Project has a successful record of remediating access tracks and worksites in the Vestfold Hills, which have previously been affected by the use of vehicles, excavation, and drilling equipment in previous field seasons. Remediation techniques are proposed to be adopted for the 2021/2022 season to visually reinstate areas to resemble pre-work conditions where track use, excavation and drilling have been undertaken. Based on visual photographic records reviewed from previous field seasons, it is anticipated that ground disturbance may be discernible at the completion of the field season, but that it will not be visible in the future due to natural weathering processes, as evident from the works undertaken 2013-2014, discussed in Section 6.1.

Initial rehabilitation of disturbed areas is proposed to be completed with the use of the 30t excavator, to return the temporarily cleared material back to their original position, as far as reasonably practicable.

Historical understanding indicates several hundred meters of track can be remediated per day using the excavator and an appropriately skilled plant operator. The second stage of the proposed rehabilitation process requires the manual raking of soil to remove evidence of tracks and scarify the surface before scattering finer sized surface materials (cobbles, gravel, and sand). Historical understanding indicates a group of three people can remediate a length of 300 m of track per day. Example images of remediated access tracks are provided in Figure 13 and Figure 14 for reference.

It is the intention that disturbed ground will be remediated at the completion of geotechnical investigation works. Whilst it is planned that remediation works will commence towards the end of the 2021-22 field season, it is likely that these works will be required to continue through the 2022- 23 season to minimise the evidence of visual disturbance. As with previous geotechnical investigations, photographic evidence of areas of temporary ground disturbance will be recorded prior to work commencing to provide evidence for their rehabilitation.

The approach to decommissioning and reinstatement of boreholes containing monitoring equipment is proposed to be in line with broader project remediation strategies. The potential for retaining the instrumentation may also be considered upon completion of the works, as opportunities associated with medium- and long-term monitoring may be realised.

It is proposed the boreholes containing instrumentation are be remediated upon completion of their operable use. Remediation methods may include mechanically pulling the materials from the borehole and where necessary over-drilling of the borehole, to remove all remaining instrumentation materials including PVC casings. Methods deployed during this activity will negate potential for dispersal of waste materials to the environment, namely microplastics, utilising specialise borehole decommissioning techniques in general accordance with accepted industry and environmental regulator approaches.

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Figure 13 - 1980’s existing Centreline Track in Heidemann Valley (Before 2016-2017 Season Works)

Figure 14 - 1980’s existing Centreline Track in Heidemann Valley (After 2016-2017 Season Works)

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6.2.2 Introduced Materials Associated with Field Activities 6.2.2.1 Impacts

Reflective of the approach to geotechnical site investigations undertaken as part of the 2016-2017 and 2018-2019 field seasons, introduced materials such as drilling fluid additives are required to facilitate the geotechnical drilling and downhole instrumentation process which nominally include bentonite, drilling muds and calcium chloride).

The introduction of materials into the Antarctic environment increases the risk of introducing non- native species, although this is considered to be an unlikely event due to the inorganic or highly processed nature of materials not representing a potential attractant, food or habitat, for invertebrates or plant material.

6.2.2.2 Mitigation Measures

All introduced materials required for the drilling process have been sourced and procured locally from within Australian , with material safety data sheets (MSDS) of the nominated materials, provided to the AAD Environmental Team for review and comment with respect to suitability. Of the materials proposed, no prohibited materials have been identified or precluded from use. To further mitigate the potential to introduce non-native species to the continent and minimise environmental impacts, all equipment and supplementary materials will be subjected to existing AAD cargo biosecurity screening and treatment procedures co-ordinated by the AAD Supply Services Team prior to departure.

The drilling process will require seawater to be introduced to lubricate and potentially supplemented with drilling additives to reduce the freezing potential of the fluid, reduce water loss to within the borehole, enhance borehole stability during operations and improve the quality of sample recovery. Additives to assist with the management of the drilling process only to be used where deemed necessary by the specialist drilling team with minimal volumes utilised to meet the project objectives. The permeability of the surrounding soil and rock lithologies will determine the speed at which water dissipated into the soil below the surface. The anticipated impacts of introducing seawater as a drilling fluid medium to the ground, is proposed to be negligible on the existing hyper-saline subgrade conditions in the area, noting seawater having a lower salinity than the hydrological regime. Seawater is anticipated to dilute the ground water in most places where there is no surface meltwater nearby (i.e. soil salinity from previous investigations was measured to vary from two to four times that of seawater). Where there is fresher meltwater in the system, seawater is expected to marginally increase salinity in the immediate vicinity of the borehole, however this is expected to dissipate and return to equilibrium within a short period due to the seasonal cycle of snow accumulation and melt contributing to the seasonal dilution of the hydrological system across the entire project area.

Following discussions with AAD’s Science Branch Environmental Protection specialists, it is proposed that the direct discharge of drilling fluids to the marine environment would provide a greater opportunity to minimise environmental impacts in comparison to a terrestrial discharge in the vicinity of the worksite. The marine environment is proposed to provide a greater buffering capacity to absorb seawater-based drilling fluid waste discharge, with low volumes of drilling fluid be rapidly diluted and dispersed by wave and current actions, causing minimal alteration of physiochemical properties in the marine environment. Potential changes to, and impacts on, the nearshore marine environment from increased salinity and any suspended sediment in drilling

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fluids anticipated to be negligible. Discharge in the vicinity of the shoreline or Davis wharf area, is proposed to have a negligible on marine communities due to the existing disturbance of marine life due to the disturbance of the area induced by the construction and ongoing impacts of the wharf and boat ramp.

In the event water loss is encountered due to increased permeability of the ground conditions, a viscosifier may be required to assist in supporting the borehole and preventing collapse and reducing water loss when drilling into bedrock. This additive is unlikely to be required, however it is necessary to plan for its use, similar to that approved for previous field programs, in order to ensure the project can achieve its engineering goals.

During drilling operations, the drilling fluid will be recirculated within the drilling system to reduce the dependence on natural resources. The recirculated water will be captured upon completion of the borehole and passed through a “baffle box”, to facilitate the “fall out” of sediments from suspension within the drilling fluid. This process reduces the potential for reintroduction of solid material into the borehole during drilling, reducing the potential for environmental impacts associated with damage to plant and equipment. Where the excess drill cuttings cannot be returned into the borehole due to the requirement for installation of borehole instrumentation, the disposal of excess cuttings is to be in accordance with AAD Waste Management Guidelines, with import permits to be obtained from DAWE to bring landfill material back for disposal in Tasmania.

The installation of down borehole instrumentation will require the use of threaded PVC tubing. Noting that PVC shavings are known to be created during cutting processes, if unmitigated there is potential for microplastics to be introduced into the environment. It is proposed, the following efforts are made to minimise the potential for contamination associated with microplastics:

· Drilling of borehole to depths aligned with the existing lengths of PVC sections negating the requirement to modify PVC lengths · If cutting is required, cutting of plastics is to take place within Workshops and facilities on Station with offcuts considered for re-use and the remaining waste products bagged for “RTA Waste for Landfill” as per AAD Waste Management requirements · If cutting is required on site, works are to occur within the enclosed Drilling shelter to minimise the potential for environmental contamination. Offcuts are to be considered for re-use with remaining waste products bagged for “RTA Waste for Landfill” as per AAD Waste Management requirements Cutting of PVC sections within the drilling shelter with housekeeping practices to minimise the potential for airborne waste dispersal.

With respect to collection of seawater for application as drilling fluid, controls proposed include the requirement for seawater to be locally sourced, to negate the potential for transfer of non-native species between environments.

Aligned with the approach historically adopted and endorsed for geotechnical activities, photographic records of pre and post work conditions will be recorded and have been proven successful through work associated with past project work described in Section 2.2.

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6.2.3 Works in Proximity to Lakes and Waterbodies 6.2.3.1 Impact To supplement the geotechnical activities undertaken in previous seasons, geotechnical boreholes and test pits excavations are proposed along the concept aerodrome alignment, which interfaces with known lakes and waterbodies.

Geotechnical ground-breaking works are required to inform the construction planning and engineering design and have the potential to disturb the ground in the vicinity of, and introduce environmental impacts to, lacustrine ecologies if mitigations measures are not adopted.

Potential impacts relating to the geotechnical fieldworks in the vicinity of lakes and waterbodies may include the introduction of sediment or liquids associated with the fieldwork operations impacting waterbody physiochemical composition.

6.2.3.2 Mitigation Measures

To minimise the potential for environmental impact to lakes and waterbodies, where there is potential for impacts to the waterbodies, it is proposed geotechnical drilling will not be undertaken within 30m when frozen, and 100m when unfrozen, where observed at the time of drilling. Known waterbodies within the project extents are defined within the Scientific Committee on Antarctic Research (SCAR) Composite Gazetteer of Antarctica and include:

· Abatus Bay · Camp Lake · Heidemann Bay · Lake Dingle · Lake Stinear · Larelar Lake · Ripple Lake · Station Tarn · Weddell Arm · Weddell Lake

To further minimise the potential environmental impacts to identified water bodies during the fieldwork program, it is proposed works in the vicinity of waterbodies are undertaken during the cooler months when the surface of the water body is observed to be frozen, with discharge of excess seawater-based drilling fluids will be directed to the marine environment..

The approach to works being undertaken in the shoulder and winter seasons when the surface is frozen, is proposed to limit the potential for contaminants entering the waterbody system due to the frozen layer acing as a temporary natural barrier. The frozen surface is also proposed to provide a greater opportunity to facilitate on-site remediation efforts as required.

It is the intention that disturbed ground will be remediated at the completion of geotechnical investigation works. Whilst it is planned that remediation works will commence towards the end of the 2021-22 field season, it is likely that these works will be required to continue through the 2022- 23 season to minimise the evidence of visual disturbance. As with previous geotechnical investigations, photographic evidence of areas of temporary ground disturbance will be recorded prior to work commencing to provide evidence for their rehabilitation.

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6.2.4 Fuel Spills, Waste Disposal and Loss of Equipment. 6.2.4.1 Impact

As detailed in Section 5.1 the Vestfold Hills, and project extent is within an ice-free area. The proposed fieldwork operations are proposed to occur within, and beyond the Davis Station Limits and have the potential to introduce environmental impacts associated with hydrocarbon spills,

discharges of firefighting extinguishers (primarily CO2, with dry powder as contingency) to ground, waste disposal, loss of equipment and anthropogenic activities if unmitigated.

If mitigation measures are not in place, there is the potential for adverse environmental impacts to visual and aesthetic values and ecological and hydrological regimes.

6.2.4.2 Mitigation Measures.

Due to the challenges of remediating fuel spills in ice free areas in Antarctica, the AAD and project will every effort to prevent accidental fuel and hydraulic spills through careful attention to fuel management at its stations and in the field.

Fuel spills and leaks are most likely to occur through overfilling and splashes when refuelling equipment. The project will utilise the fuel stored with the Davis Station supplies. Where refuelling within station cannot be achieved, volumes of fuel to be transported and transferred will be minimised to a volume as low as practicable. Where on station refuelling is not possible, fuel will be transported to site within a trailer mounted, multi-walled fuel transport cell to support the required location, Figure 15.

Figure 15 – Davis Station Trailer Mounted Fuel Transport Cell

Noting off-site refuelling activities currently occur at all AAD Stations, it is proposed mitigation actions are to be aligned with the existing AAD refuelling principles to mitigate fuel leak and spill potential. Minor fuel leaks can occur during fuel transfer and usually associated with opening and closing hose and pump connections. Proactive measures are proposed to be in place to ensure fuel is contained from these ,mostly minor drips and spills with appropriate containment and clean-up equipment available. The mini-spill kits supplied by the AAD proposed to be made available which

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include absorbent pads, a mini-boom, nitrile gloves and contaminated disposal bag, as well as response and clean-up instructions. Buckets should be on hand to collect fuel for reuse and recover any contaminated snow or soil for treatment on station. Spill trays lined with absorbent pads should be located under all connection points during operation and disconnection.

· Checking of equipment · Refuelling equipment · Communication devices · PPE and · Review of relevant safety and hazard documentation · Preparation and availability of appropriate fuel spill equipment with capacity of soaking materials and containers on stand-by to exceed the expected leak quantity by 50 % · Clear definition of personnel roles, to include refuelling crew, spotter, and supervisor

Noting the controls available, it is proposed there would be little effect on ecological communities as a result of a minor fuel / hydraulic spill or leak.

Hydraulic hoses and fittings associated with the geotechnical drilling rig are predominantly located within the drilling container. Fittings and hoses are to be inspected on a routine basis for signs of wear or potential for leak. Where wear is observed, fittings and hoses are to be repaired and/or replaced. Locating the drilling rig within a shelter and developing a routine equipment inspection regime is proposed to mitigate the potential for a hydraulic leak to the environment.

All mechanised equipment is proposed to be demobilised from site upon completion of works. Monitoring instrumentation will remain in place until decommissioned with borehole reinstated in accordance with project remediation strategies. Drilling waste will not be left in the field, with all materials returned to station. Where materials cannot be reused, items are to be sorted, bagged / packaged, and marked for recycling or landfill as per the AAD Waste Management Procedures and /or Environmental Officer requirements,

Fire extinguishers will be located in accessible locations within the drilling and support container and within vehicles, with locations identified as part of the drilling plant induction processes

6.2.5 Vehicle and Equipment Emissions 6.2.5.1 Impacts

Air pollution will result from the movements of the field team and equipment including fuel by helicopter and other transport, the use of machinery and equipment and the use of generators at the fieldwork locations. Emissions will include carbon dioxide, carbon monoxide, nitrous oxides, sulphur dioxide, particulates, and trace amounts of heavy metals.

Aligned with the previously approved geotechnical activities undertaken to date, emissions are proposed to be rapidly dispersed by wind, although there will be some deposition of pollutants in the local area. Heavy larger particles, such as soot, are likely to have relatively short maximum transport distances, with background levels in surface snow samples potentially being reached in vicinity of the drill / excavation site, with metals having a greater transport distance. Whilst it is acknowledged that the emissions resulting from the logistics and other field activities all contribute to a reduction in air quality, the impacts are proposed to be minor and unavoidable.

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6.2.5.2 Mitigation Measures

Logistics and fieldwork operations will be planned to maximise efficiencies by minimising the quantum and length of vehicle movements. All equipment used on site will be well maintained to enhance efficiency and will be shut down when not required to save fuel and reduce the potential for environmental impact.

Further opportunities to minimise vehicle emissions, include the temporary formation of a small, temporary laydown area on the Ridge site for field work equipment and consumables. This will facilitate the positioning of equipment and materials closer to the work site to reduce transit movements between the Ridge and Station.

6.2.6 Native Flora, Fauna and Habitat 6.2.6.1 Impacts

Windblown dust and noise generated from temporary access track formation, vehicle movements, geotechnical drilling and through excavation activities may have an impact on flora and fauna located within vicinity of the drilling or excavation location. Mitigation measures to reduce such impacts are summarised in the following section.

It is anticipated noise generated by the drilling and excavation equipment will be less than 90dB, with the drilling rig being containerised further reducing noise levels.

6.2.6.2 Mitigation Measures

As part of the project planning, consideration has been given to minimising the impacts on native fauna. It is proposed the majority of works are undertaken over winter as wildlife are generally absent from the area during this period. To further mitigate potential impacts, the area in the vicinity of the works is to be visually assessed for native fauna. To aid the project team in understanding native wildlife habitats, the on-site DAP Environmental Officer –Wildlife is proposed to undertake a familiarisation workshop with a further site-based session undertaken prior to works commencing.

Fieldwork locations are to be assessed for the presence of native wildlife prior to start, and are to be located at distances greater than the nominated minimum AAD wildlife approach distances:

· Giant petrels and albatrosses — 100m · Breeding/moulting emperor penguin — 50m · All other breeding/moulting birds and seals — 15m · Non-breeding seal or bird — 5m · All vehicles — 200m from all wildlife

In the event native wildlife approach the works site following the commencement of works, works are to continue with caution, on the condition operations will not cause harm.

The microbiota and localised soil processes directly impacted by soil disturbance caused by temporary track formation, borehole drilling and test pit excavations are inevitable. These localised effects while unavoidable, are considered to be of a low impact and short-term in nature.

Due to the fieldwork programme commencing in the winter months, there is a reduced potential for native fauna to be present, reducing the long-term potential for noise and dust from drilling and excavation activities having a notable impact the environment. The duration of drilling works at

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each borehole location will be dependent on the target depth of each borehole. Shallower boreholes (5m depth) are anticipated to be completed within one working day, with the deeper boreholes (up to 60m) anticipated to be complete within 1 week. When vehicles, equipment, drilling rig and excavators are not in use, they are to be turned off to minimise noise and emission impacts.

To mitigate the potential for dust generating activities, the following controls are proposed:

· Works which have the potential to generate excessive dust are to occur on low wind days · Vehicles speeds to be limited to <30km/h as per AAD off-station vehicle travel requirements (SOP V1 – CH4.10.5)

Downhole and surface monitoring instrumentation is proposed to be installed throughout the project site. Monitoring instrumentation and dataloggers installed within boreholes will be protected from the environment by monument type covers, which will also prevent native fauna entrapment. Other instrumentation, including lake depth markers and existing in-situ survey pins are to be fitted with PVC caps to prevent fauna impalement. All project related assets are to be inspected weekly to assess condition and minimise impacts to native fauna.

The use of Remotely Piloted Aircraft is proposed as part of the 2021/2022 summer season. to collect survey data and aerial imagery, which if unmitigated have the potential for wildlife disturbance. In the event RPA activities are required as part of the program, works are to be undertaken in accordance with the Aviation Standard operating Procedures documented within Volume 5of the Operations Manual which details all aerial operations using unmanned aerial systems (UAS) will be conducted in accordance with the conditions and limitations placed on the Remotely Piloted Aircraft Operator’s Certificate (ReOC) and/or the conditions and limitations set out by the Department of Agriculture, Water and Environment and the Australian Antarctic Division.

Excavations may pose an entrapment hazard to native wildlife. To minimise the impacts to wildlife, excavations are not to be left unattended, and are required to be backfilled upon completion and at the end of each day as required.

To mitigate against the introduction of non-native species into Antarctica, all equipment and materials will be subjected to AAD’s existing pre-deployment bio-security procedures co-ordinated by the Supply Services Team. When on site, sampling equipment will be cleaned before moving between sites to avoid the introduction of non-native species.

6.2.7 Cultural Heritage Values and Historic Importance 6.2.7.1 Impacts

The Vestfold Hills have several structures that have been ascribed as having heritage values. The locations of these sites is understood, and earthwork activities will be planned to avoid interfering with these sites and maintain a minimum of 100m distance. It is therefore considered that there will be no impact on cultural heritage values and historic importance.

6.2.8 Interface with Other Programs or Projects in the Local Area 6.2.8.1 Impacts Impacts on other programs or projects are considered to be less this previous field seasons. This is due to a more localised work area, a reduction in Station population and lower overall demand for key assets. MARCH 2021

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6.2.9 Cumulative Impacts

Previous geotechnical field work has been carried out in the regions around Davis station, Adams Flat and the Ridge Site which have had impacts of no more than minor or transitory. The 2012-13 Field Season was assessed at Preliminary Assessment Level; the 2016-17 and 2017-18 Field Seasons were covered by a separate Initial Environmental Evaluation.

During previous field seasons, the Project identified multiple sites at Adams’ Flat showing previous evidence of ground disturbance. It included pitting and dozer scraping works where caterpillar tracks are still clearly visible after over 30 years. There is existing infrastructure in these areas, including the well-established Dingle Road located along the northern margin of Heidemann Valley, as well as older less established vehicular tracks established along the centre of Heidemann Valley in the 1980’s. Dingle Road is within recreational limits for Davis Station and as such is subject to vehicle and foot traffic throughout the summer and to a lesser extent during winter. The AAD has well developed environmental guidelines and procedures for mitigating impact associated with operations and recreational activities in this area.

Drilling, excavation, and access track formation presents the greatest potential for cumulative impact. However, these activities are each discontinuous in nature and (given space constraints on existing tracks) are unlikely to take place at the same time in the same area. The mitigation methods outlined in this IEE (including the Tables contained in Annex 1 and Annex 2 to this IEE) also aim to prevent or minimise impacts and prevent any lasting alteration to the landscape, and/or impacts on wildlife and other values.

There is potential for impact as a result of increased foot and vehicular traffic with drilling fluid cartage by light truck or support vehicle . When resources are available, helicopters will also be utilised to transport drilling fluids, further reducing the impacts and demand on access track use, however, most work of any intensity is to be limited to, and focussed within, existing disturbed sites. The cumulative impact from foot traffic is considered to be low, given site access is to be prohibited to the wider non-project Station community .

There is expected to be daily traffic in support of other projects and/or recreational use over the course of this field season along Dingle Road. Additional usage under this project is not expected to worsen the condition of Dingle Road beyond existing operational conditions.

Areas further afield from Davis Station are less disturbed and may be more susceptible to impact. Beyond the temporary access tracks, these areas are proposed to be subject only to irregular foot traffic with negligible cumulative impacts anticipated. 6.3 Environmental Monitoring and Management Several measures are proposed to be adopted to record and monitor the impacts of proposed 2021- 22 field activities. Examples of mitigation measures include:

· photographs before, during, and after each activity potentially inducing environmental disturbance, to assist in reporting and documentation of remediation efforts

· upkeep of field notes and site diaries to record time, location, and identity of wildlife presence in vicinity of project activities if encountered

· assessment of activity sites in future seasons to review evidence of activities, with appropriate project remediation strategies developed.

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To ensure compliance to environmental procedures, requirements and conditions, the project activities are proposed to be audited on a routine and ad-hoc basis by members of the Station leadership team, nominally including the Station Leader, Station Environmental Officer or Project Environmental Officer- Wildlife or delegate. Due to the acknowledged Station operating constraints, the opportunity for a dedicated, independent auditor to be present is not achievable. To provide the Station Leadership Team with appropriate information and training to undertake an appropriate audit assessment. In collaboration with the AAD Environmental Management Team, an audit framework is proposed to be developed to aid auditors and ensure thorough assessments can be undertaken. Audit checklists and inspection proforma are proposed to be developed by the AAD Environmental Management Team prior to works commencing, to assist the on-site team. The framework is to be developed in accordance with the guidance set out as part of the AAD Operations Manual Volume 1: Station and Field Operating Procedures, Chapter 2: Environmental Management.

The AAD Operations Manuals and Standard Operating Procedures contain contingency plans to be followed in the case of accidents or emergencies that have unexpected or adverse impacts on the environment. The AAD’s IHIS incident reporting tool will be used to report all incidents, including those that may have an adverse impact on the environment, to the Station Leader, Operations Managers and Manager of the Territories Environment and Territories Section. All avenues of reducing impacts will be considered and performed with appropriate manager’s approvals.

In the unlikely event of an emergency, or unexpected impacts on the environment, work is to cease immediately with impacts assessed in consultation with the Station Leader, Station Coordinator, Operations Manager and DAP Project Manager, and reported via IHIS. Unexpected impacts on the environment and/or any environmental emergencies will be reported to the Territories, Environment and Treaties Manager. Where appropriate, a variation may be sought regarding environmental authorisation and if impacts are deemed acceptable and warranted by the regulator, a variation may be approved.

The AAD’s Territories, Environment and Treaties Section will be provided a Report of Activities to report on Authorised and Permitted activities under the ATEP Act, following the completion of the 2021-22 field season. 7 Conclusion This IEE concludes that, provided the recommended mitigations are implemented, the proposed 2021-22 field activities are likely to have no more than a minor or transitory impact on the Antarctic environment.

It is therefore concluded that the proposed activities should be allowed to proceed, and that a Comprehensive Environmental Evaluation is not required. 8 Contact details This IEE was prepared by Ally Gulliver-Davies, Aron Gavin and Andy Sharman of the AAD and Ian Ullah of AECOM Australia Pty. Ltd., on behalf of Stuart Gibson and Adrian Young for the Australian Antarctic Division, Department of Agriculture, Water and the Environment. All enquiries should be directed to [email protected]

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67 INITIAL ENVIRONMENTAL EVAULATION 2021-22 FIELD SEASON 9 References AAD (2015). ‘Trends and sensitivity to change.’ http://www.antarctica.gov.au/science/conservation- and-management-research/terrestrial-and-coastal-ecosystems/trends-and-sensitivity-to-change; of 28 October 2015, accessed 8 November 2015. Cavicchioli, R. (2015) Microbial ecology of Antarctic aquatic systems. Nature Reviews Microbiology, vol. 13, no. 11, pp. 691 - 706

Clark, C., Kinny, P.D., and Harley, S.L. (2012). Sedimentary provenance and age of metamorphism of the Vestfold Hills, East Antarctica: Evidence for a piece of Chinese Antarctica? Precambrian Research, 196, 23–45.

Colhoun, E.A., Kiernan, K.W., McConnell, A., Quilty, P.G., Fink, D., Murray-Wallace, C.V. and Whitehead, J.(2010). Late Pliocene age of glacial deposits at Heidemann Valley, East Antarctica: evidence for the last major glaciation in the Vestfold Hills. Antarctic Science 22(1):53–64.

Collerson, K.D., Harley, S.L., Ellis, D.J., Oliver, R.L., Tingey, R.J. and Wilson, C. (2002). In: Marchant, H.J., Lugg, D.J. and Quilty, P.G. (Eds). Australian Antarctic science: the first 50 years of ANARE. Australian Antarctic Division, Kingston. Pp. 165-201.

Frankel, B.T. (2014). Landscape Rehabilitation in the Vestfold Hills. Antarctic Magazine, Issue 27, December.

Gibson, J.A.E., Paterson, K.S., White, C.A., and Swadling, K.M. (2009). Evidence for the continued existence of Abraxas Lake, Vestfold Hills, East Antarctica during the Last Glacial Maximum, Antarctic Science, 21: 269–278.

Gillies C.L., Stark J.S., Johnstone G.J., Smith S.D.A. (2013). Establishing a food web model for coastal Antarctic benthic communities: a case study from the Vestfold Hills. Mar. Ecol. Prog. Ser. 478:27–41.

Hughes, K.A., Cowan, D.A. and Wilmotte, A. (2015). Protection of Antarctic microbial communities – ‘out of site, out of mind.’ Frontiers in Microbiology 6, Article 151. 6 pp.

Kirkwood J.M., Burton H.R. (1988). Macrobenthic species assemblages in Ellis Fjord, Vestfold Hills, Antarctica. Mar. Biol. 97:445-457.

Marchant, H.J., Bowman, J., Gibson, J., Laybourn-Parry, J. and McMinn, A. (2002). Aquatic microbiology: the ANARE perspective. In: Marchant, H.J., Lugg, D.J. and Quilty, P.G. (Eds). Australian Antarctic science: the first 50 years of ANARE. Australian Antarctic Division, Kingston. Pp. 237-269.

O’Brien P.E., Smith J., Stark J.S., Johnstone G., Riddle M., Franklin D. (2015). Submarine geomorphology and sea floor processes along the coast of Vestfold Hills, East Antarctica, from multibeam bathymetry and video data. Antarctic Science 27:566-586 Pickard, J. (ed.) 1986. Antarctic Oasis: terrestrial environments and history of the Vestfold Hills. Academic Press, Sydney.

Pyper, W. (2013). ‘Promiscuous community reveals hidden values.’ http://www.antarctica.gov.au/about-us/publications/australian-antarctic-magazine/2011- 2015/issue-25-december-2013/science/promiscuous-community-reveals-hidden-values; of 20

December 2013; accessed 31 August 2016.

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Quilty, P.G., Lirio, J.M. and Jillett, D. (2000) Stratigraphy of the Pliocene Sørsdal Formation, Marine Plain, Vestfold Hills, East Antarctica. Antarctic Science, 12: 205–216Taton, A., Grubisic, S., Ertz, D., Hodgson, D.A., Piccardi, R., Biondi, N., Tredici, M.R., Mainini, M., Losi, D., Marinelli, F., and Wilmotte, A. (2006) Polyphasic study of Antarctic cyanobacterial strains. Journal of Phycology 42:1257–1270.

Seppelt, R.D. and Broady, P.A. (1988). Antarctic terrestrial ecosystems: the Vestfold Hills in context. Hydrobiologia, 165, 174-184. Vincent, W.F. (1997). Polar desert ecosystems in a changing climate: a north-south perspective. In: Lyons, W.B., Howard-Williams, C. and Hawes, I. (Eds). Ecosystem Processes in Antarctic Ice-free Landscapes. A.A. Balkema, Rotterdam. Pp. 3-14.

Smith J., O’Brien P.E., Stark J.S., Johnstone G., Riddle M. (2015). Integrating multibeam sonar and underwater video data to map benthic habitats in an East Antarctic nearshore environment.

Estuarine, Coastal and Shelf Science 164:520–536.

Stark J.S., Bridgen P., Dunshea G., Galton-Fenzi B., Hunter J., Johnstone G., King C., Leeming R., Palmer A., Smith J., Snape I., Stark S., Riddle M. (2016). Dispersal and dilution of wastewater from an ocean outfall at Davis Station, Antarctica, and resulting environmental contamination. Chemosphere 152:142-157.

Stilwell, J.D. and Long, J.A. (2011). Frozen in time: prehistoric life in Antarctica. CSIRO Publishing, Collingwood, Victoria. 238 pp.

Terauds, A., and Lee, J. R. (2016) Antarctic biogeography revisited: updating the Antarctic conservation biogeographic regions. Diversity and Distributions 22:836-840.

Terauds, A., Chown, S.L., Morgan, F., Peat, H.J., Watts, D.J., Keys, H., Convey, P. and Bergstrom, D.M. (2012). Conservation biogeography of the Antarctic. Diversity and Distributions 18:726-241.

Tucker M.J., Burton H.R. (1988). The inshore marine ecosystem off the Vestfold Hills, Antarctica. Hydrobiologia 165:129-139.

Vincent, W.F. (1997). Polar desert ecosystems in a changing climate: a north-south perspective. In: Lyons, W.B., Howard-Williams, C. and Hawes, I. (Eds). Ecosystem Processes in Antarctic Ice-free Landscapes. A.A. Balkema, Rotterdam. Pp. 3-14.

Williams R. (1988). The inshore marine fishes of the Vestfold Hills region, Antarctica. Hydrobiologia 165:161-167.

Zwartz, D., Bird, M., Stone, J., and Lambeck, K. (1998). Holocene sea-level change and ice-sheet history in the Vestfold Hills, East Antarctica. Earth and Planetary Science letters, 155: 131-145.

Scientific Committee on Antarctic Research (SCAR) Composite Gazetteer of Antarctica. - https://data.aad.gov.au/aadc/gaz/scar/download.cfm

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APPENDIX 1

Table 1 - Detailed description of aspects of the proposed activity No. Activity Description Objective Locations Number of Frequency of Activity Transport method Equipment to be used Method to be used sites

• 1 • Site Access and • Preparation of new site • Preparation of borehole • Marchants Landing, • Minimum • Works to be undertaken • Ute, light vehicle, • Station 30T excavator will be • Alignments and locations of temporary site laydown Preparation access routes and working platforms, Davis Link, Adams required to prior to arrival of light truck, required to undertake any areas, working platforms and culverts are to be installation of asset formation of new temporary Flat, Ridge Site and meet project geotechnical drilling mechanical plant potential temporary surface visually assessed for operational and environmental protection culverts access tracks and installation Heidemann Valley objectives (Up equipment, where and Hagglunds obstruction clearance. suitability of asset protection culverts to 7500m) possible and as where practical Station telehandler and front- • Areas are to be assessed for environmental coordinated between end loader is anticipated to sensitivities, including potential for avian habitation. Field Coordinator, be required to facilitate in the • Works are to be undertaken in accordance with Work Station Operations placement of asset protection Health and Safety requirements (Chapter 1 of the Coordinator and Station culverts as required Operations Manual Volume 1: Station and Field), Leader Environmental Protection and Management (Chapter 2 of the Operations Manual Volume 1: Station and Field). • Pre- and post-work photographs are to be recorded to detail efforts undertaken to minimise adverse impacts potentially associated with ground disturbance

• 2 • Geotechnical • Geotechnical borehole • Collect subsurface soil and • Marchants Landing, • Up to 150 • Works to be undertaken • ATV, ute, light • Skid mounted or modular • Drilling unit positioned to minimise environmental Borehole drilling drilling using skid mounted rock samples to inform Davis Station limits, on a daily basis as vehicle, low drilling rig and ancillary impacts and ensure personnel safety measures are (including or modular, containerised geotechnical data necessary Davis Link, Adams coordinated between ground pressure equipment , including drilling addressed. introduction of machinery. for SIP and DAP engineering Flat, Heidemann Field Coordinator, support vehicle additives, pumps, generators, • Drilling unit to be levelled using outriggers and / or materials). design Valley and the Ridge Station Operations and Hagglund and support vehicles, core trays, dunnage. Site Coordinator and Station Helicopter sampling equipment. • Rotary drilling techniques are to be adopted to Leader support, as • facilitate the recovery of soil and rock cores of up to required 100mm diameter and 60m in depth • Seawater, supplemented with drilling additives where required, is to be used as a lubricant • Volume of water required to support the drilling activities will be dependent on the borehole depth and the encountered ground conditions, with daily volumes anticipated to be between 500 and 5000 litres per day, depending on ground conditions • Samples to be visually logged, photographed, tested, cleaned, and packaged for RTA. • Works are to be undertaken in accordance with Work Health and Safety requirement (Chapter 1 of the Operations Manual Volume 1: Station and Field), Environmental Protection and Management (Chapter 2 of the Operations Manual Volume 1: Station and Field) • Pre- and post-work photographs are to be recorded to detail efforts undertaken to minimise adverse impacts potentially associated with ground disturbance

• 3 • Supply of water to • Temporary deployment of • Supply of water to drilling • Heidemann Bay, • Up to 150 • Throughout field season • Ute, light truck, • IBC tanks for transport by Ute, • Drilling will use seawater and pooled snow-melt drill sites tanks (IBCs) of seawater or sites to enable drilling, West Bay, Abatus on daily basis Hagglunds and/or light truck, Hagglunds and/or water (where available). (seawater/ meltwater. nominally up to 5000 litres Bay, Davis Station • Removal at end of field helicopters will be helicopters • Seawater will be pumped into IBC’s for storage and meltwater). per day (depending on and/or meltwater season. used to deploy and • Ice auge, water pumps and transportation to the drilling site (through sea ice if ground conditions) ponds as required to recover IBCs. hoses necessary). source water.

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No. Activity Description Objective Locations Number of Frequency of Activity Transport method Equipment to be used Method to be used sites

• 4 • Downhole • Installation of downhole • Installation of downhole • Marchants Landing, • Up to 60 • Downloading of data • ATV, ute, light • Laptop, instrumentation • Borehole instrumentation to be connected to laptop monitoring monitoring monitoring instrumentation Davis Station limits, locations proposed at nominally vehicle, Hagglund hardware by cables and / or through specific hardware for instrumentation instrumentation at selected to facilitate collection of Davis Link, Adams fortnightly intervals or foot monthly transfer. (including locations insitu data to inform design Flat, Heidemann following installation • Asset removal upon completion of operable use introduction of Valley and the Ridge materials) Site • 5 • Temporary shelter • Position mobile weather • Provide a weather shelter • Marchants Landing, • Provision of • To be relocated in • Loaded with • Low pressure mechanical • MWS will be positioned where required at each drill installation. shelter (MWS) or similar. for drilling personnel during Davis Station limits, shelter at each parallel with drilling drilling rig and plant to relocate shelter sites to minimise environmental impacts while drilling activities Davis Link, Adams borehole equipment ancillary structure with skid mounted providing optimal safety outcomes Flat, Heidemann location (Up to equipment for drilling rig Valley and the Ridge 150) towing. Site

• 6 • Hand-Augered • Hand drilling boreholes into • Hand drilling boreholes into • Marchants Landing, • Up to 50 • Works to be undertaken • ATV, ute, light • Manual hand auger • Assessment of site for environmental sensitivities boreholes. soil in order to sample soil in order to sample Davis Station limits, location on an ad-hoc basis vehicle, Hagglund equipment • Manual auger drilling techniques are to be adopted groundwater; obtain soil groundwater; obtain soil Davis Link, Adams throughout the season or foot to recovery of soil samples of up to 100mm diameter samples and collect data to samples and collect data to Flat, Heidemann as coordinated between to a nominal depth of 3m below surface inform engineering inform design team of Valley and the Ridge Field Coordinator, • Recovered samples are to be visually logged, concepts. existing ground conditions. Site. Station Operations photographed, tested, and prepared for RTA Coordinator and Station transport. Leader

• 7 • Test pit • Excavation of materials • Sample collection for bulk • Marchants Landing, • Up to 100 • Works to be undertaken • Excavator (self- • 30T excavator, manual hand • Assessment of the proposed site for environmental excavation (30T within test pits up to analyses for geotechnical Davis Station limits, on an ad-hoc basis drive), personnel tools, hand tools, sample sensitivities excavator). approximately 4.0 m deep purposes and exposure of Davis Link, Adams throughout the season movements via containers, camera, and • Positioning of the excavator to commence activities and up to 2-meter-wide stratigraphy for mapping Flat, Heidemann as coordinated between light vehicle, , ATV, notebooks. • Sediment to be excavated with the excavator bucket (actual depth will depend • Collect data to inform design Valley and the Ridge Field Coordinator, Hagglund only, with rock breaking works not required. on different soil layer and constructions planning Site Station Operations • Visual geotechnical assessment of the test pit side thickness and stratigraphy) Coordinator and Station walls with collection of soil samples. Leader • Test pits backfilled with a “last out, first in approach”. Test pits not to remain open overnight and are to be backfilled immediately upon completion. • Pre- and post-work photographs are to be recorded to detail efforts undertaken to minimise adverse impacts potentially associated with ground disturbance • Works are to be undertaken in accordance with Work Health and Safety requirements (Chapter 1 of the Operations Manual Volume 1: Station and Field), Environmental Protection and Management requirements (Chapter 2 of the Operations Manual Volume 1: Station and Field).

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No. Activity Description Objective Locations Number of Frequency of Activity Transport method Equipment to be used Method to be used sites

• 8 • Test pit • Excavation of materials • Sample collection for bulk • Marchants Landing, • Up to 50 • Works to be undertaken • Excavator (self- • 3T excavator or portable • Assessment of the proposed site for environmental excavation (3T within test pits up to analyses for geotechnical Davis Station limits, on an ad-hoc basis drive), personnel digging machinery, hand sensitivities excavator). approximately 3.0 m deep purposes and exposure of Davis Link, Adams throughout the season movements via tools, sample containers, • Positioning of the excavator to commence activities and up to 1 meter wide stratigraphy for mapping Flat, Heidemann as coordinated between light vehicle, , ATV, camera, and notebooks. • Sediment to be excavated with the excavator bucket (actual depth will depend • Collect data to inform design Valley and the Ridge Field Coordinator, Hagglund only, with rock breaking works not required. on different soil layer and constructions planning Site Station Operations • Visual geotechnical assessment of the test pit side thickness, stratigraphy and Coordinator and Station walls with collection of soil samples. WHS considerations). Leader • Test pits backfilled with a “last out, first in approach”. Excavations will allow bulk Test pits not to remain open overnight and are to be sample collection to backfilled immediately upon completion. facilitate geotechnical • Pre- and post-work photographs are to be recorded assessments and exposure to detail efforts undertaken to minimise adverse of stratigraphy for mapping impacts potentially associated with ground and collection of data to disturbance inform infrastructure • Works are to be undertaken in accordance with Work design. Health and Safety requirements (Chapter 1 of the Operations Manual Volume 1: Station and Field), Environmental Protection and Management requirements (Chapter 2 of the Operations Manual Volume 1: Station and Field)

• 9 • Test pit • Excavation of materials • Sample collection for bulk • Marchants Landing, • Up to 20 • Works to be undertaken • By vehicle along • Hand tools, sample • Assessment of the proposed site for environmental excavation within test pits up to analyses for geotechnical Davis Station limits, on an ad-hoc basis tracks, by foot containers, camera, and sensitivities (Manual). approximately 2 m deep purposes and exposure of Davis Link, Adams throughout the season elsewhere. notebooks. • Sediment to be excavated with hand tools only and up to 500mm wide stratigraphy for mapping Flat, Heidemann as coordinated between • Visual geotechnical assessment of the test pit side (actual depth will depend • Collect data to inform design Valley and the Ridge Field Coordinator, walls with collection of soil samples. on different soil layer and constructions Site Station Operations • Test pits backfilled with a “last out, first in approach”. thickness, stratigraphy and Coordinator and Station Test pits not to remain open overnight and are to be WHS considerations). Leader backfilled immediately upon completion. Excavations will allow bulk • Pre- and post-work photographs are to be recorded sample collection to to detail efforts undertaken to minimise adverse facilitate geotechnical impacts potentially associated with ground assessments and exposure disturbance of stratigraphy for mapping • Works are to be undertaken in accordance with Work and collection of data to Health and Safety requirements (Chapter 1 of the inform infrastructure Operations Manual Volume 1: Station and Field), design Environmental Protection and Management requirements (Chapter 2 of the Operations Manual Volume 1: Station and Field)

• 10 • Dynamic Cone • Measurements of surface • Measure soil strength that • Marchants Landing, • Up to 137 • Once at each test pit • ATV, ute, light • Hand tools, geotechnical • Measurements made of soil strength by use of Penetrometer soil strength properties in may support the design of Davis Station limits, locations vehicle, Hagglund tools, Dynamic Cone portable Dynamic Cone Penetrometer Testing order to inform design. project infrastructure Davis Link, Adams or foot Penetrometer Flat, Heidemann Valley and the Ridge Site

• 11 • Geological • Inspect and map rock • To map the geology and • Marchants Landing, • As required to • Works to be undertaken • ATV, ute, light • Geological hammer, Schmidt • Walking over terrain to map physical geotechnical mapping and outcrops, manually test geomorphology, retrieve Davis Station limits, sufficiently on an ad-hoc basis vehicle and Hammer, handheld geological and geological conditions and assess in situ geological testing. bedrock for geotechnical rock samples, and test rock Davis Link, Adams characterise throughout the season Hagglund, measurement conditions. Collection of representative samples for analyses, map the geology strength. Flat, Heidemann the areas. as coordinated between helicopter or foot instrumentation shovel, rock strength analysis at station or to be prepared for and geomorphology, and Valley and the Ridge Field Coordinator, as required and trowel, rake, broom etc. analysis following RTA. collect representative Site Station Operations available samples for rock strength Coordinator and Station analysis at station or to be Leader prepared for analysis following RTA.

MARCH 2021 72 INITIAL ENVIRONMENTAL EVAULATION 2021-22 FIELD SEASON

No. Activity Description Objective Locations Number of Frequency of Activity Transport method Equipment to be used Method to be used sites

• 12 • Geophysical • Non-invasive geophysical • Provide a more • Marchants Landing, • Number of • Daily throughout the • Ute, light vehicle, • Geophones, seismic source, • Alignment of survey transects are to be determined Survey survey to inform comprehensive, 3- Davis Station limits, individual 2021/2022 Summer field light truck, datalogger and mobile following a review of the collected geotechnical engineering design dimensional geotechnical Davis Link, Adams transects to be season Hagglunds or computer hardware drilling and excavation information engineering assessment of Flat, Ridge Site and determined Helicopter support • Grid survey with survey transect spacings ranging areas within the project site Heidemann Valley following a where practical to from 25m to 50m centres to maximise program review of the transport and • Seismic arrays consisting of geophones and opportunities and minimise outcomes of relocate survey associated cabling is to be laid along the nominated potential environmental the 2021 equipment transects connected to datalogging equipment. impacts during and following Winter drilling • A seismic signal is to be generated by hitting a Aerodrome construction. program. baseplate with a falling weight. Allowance of • Works are to be undertaken in accordance with Work 20,000 linear Health and Safety requirements (Chapter 1 of the meters of Operations Manual Volume 1: Station and Field), geophysical Environmental Protection and Management survey to be requirements (Chapter 2 of the Operations Manual made for each Volume 1: Station and Field) proposed • To document evidence of activity disturbance on the survey environment, pre- and post-work photographs are to technique be recorded to detail efforts undertaken to minimise adverse impacts

• 13 • Re-establishment • Enable access to sites of • Identification of temporary • Marchants Landing, • Lengths of new • Works to be undertaken • Excavator (self- • Excavator • Assessment of the proposed alignment to identify of old access geotechnical interest. access routes to sites of Davis Station limits, or re- on an ad-hoc basis drive), personnel environmental sensitivities tracks and/or new Existing tracks and geotechnical interest. Davis Link, Adams established throughout the season movements via • Clearance of surface obstructions to facilitate vehicle temporary access disturbed ground from Flat, Heidemann access tracks as coordinated between ute, ATV, Hagglund access tracks historical field seasons will Valley and the Ridge are dependent Field Coordinator, or foot. • Materials moved to accommodate access track to be be prioritised where Site on the project Station Operations stockpiled as windrows to facilitate reinstatement practical, following a requirements Coordinator and Station • Works are to be undertaken in accordance with Work feasibility assessment of and are to be Leader. Track use to Health and Safety requirements (Chapter 1 of the the site conditions. minimised to vary depending on work Operations Manual Volume 1: Station and Field), meet project site location and Environmental Protection and Management goals. It is duration of activity. requirements (Chapter 2 of the Operations Manual anticipated Volume 1: Station and Field) potential new • To document evidence of visual remediation temporary activities, pre- and post-work photographs are to be access tracks recorded to detail efforts undertaken to minimise will be less than adverse impacts potentially associated with ground 7500m in disturbance length

MARCH 2021 73 INITIAL ENVIRONMENTAL EVAULATION 2021-22 FIELD SEASON

No. Activity Description Objective Locations Number of Frequency of Activity Transport method Equipment to be used Method to be used sites

• 14 • Near-surface • Measurements of near • Collect data on rates of • Marchants Landing, • Up to 15 • Works to be • ATV, ute, light • V-notch weirs (composed of • Assessment of environmental sensitivities Water Flow surface water movement. water movement to help Davis Station limits, locations undertaken on an ad-hoc vehicle Hagglund or wood / metal formwork), • Excavation of temporary holding / discharge basin Monitoring. Collection of data to assess inform project design. Davis Link, Adams basis throughout the helicopter support impermeable sheeting to upstream of the V-notch weir, up to 1.5m deep and rates of water movement to Flat, Heidemann season as coordinated as required prevent surface flow 3m in width lined with impermeable sheeting inform project design. Valley and the Ridge between Field migration, excavation • Installation of V-notch weir, comprising a sheet of Site Coordinator, Station equipment (manual or plywood with “V-notch” cut to facilitate water flow Operations Coordinator excavator) and handheld • Requirement for weir to be “pinned” to ensure and Station Leader. Flow tools. structural form and integrity over the field season. measurements to be • Works are to be undertaken in accordance undertaken on a bi- with Work Health and Safety requirements weekly basis upon (Chapter 1 of the Operations Manual Volume installation 1: Station and Field), Environmental Protection and Management requirements (Chapter 2 of the Operations Manual Volume 1: Station and Field) • To document evidence of visual remediation activities, pre- and post-work photographs are to be recorded to detail efforts undertaken to minimise adverse impacts potentially associated with ground disturbance

• 15 • Lake and • Measurement of water • Measurement of seasonal • Marchants Landing, • Up to 20 • Installation proposed • ATV, ute, light • Level gauge marker, stake, • Equipment is to be inspected and cleaned prior to Waterbody level body water levels. Lake and waterbody water Davis Station limits, location early in the field season vehicle Hagglund manual hand tools, camera installation to negate the potential for contamination monitoring body levels to collect data Davis Link, Adams program to facilitate or helicopter of the lake / waterbody. on water movement near Flat, Heidemann assessment of seasonal support • Stake to be driven into lake/water body bed in order the proposed project Valley and the Ridge variations and visually (depending on site on which to mount the water level gauge. infrastructure to assist in the Site monitored weekly and resources) • Visual monitoring on lake / waterbody levels from ongoing project thereafter shore positions on a weekly basis throughout the development field season

• 16 • Terrestrial Survey • Acquisition of survey data • Acquisition of survey data to • Marchants Landing, • Various • Daily throughout the • ATV, ute, light • Real Time Kinematic Global • Survey equipment to be carried by Surveyor/ to facilitate the ongoing facilitate the ongoing project Davis Station limits, 2021/2022 Summer field vehicle Hagglund Positional System, terrestrial Surveyor's Assistant to establish benchmarks to project design design Davis Link, Adams season or helicopter laser scanner and RPA correlate project wide survey information. Flat, Heidemann support (drone). Temporary markers • Terrestrial laser scanner to be mounted on tripod for Valley and the Ridge (depending on site to set out survey sites (eg stability to acquire point cloud survey data Site . and resources), steel rod with plastic tab • Multiple positions of terrestrial laser scanner affixed, 500 mm long). required to overlap data points to facilitate Permanent markers installed processing of data. with 6inch rock bolts with • Where surface conditions preclude the use of the small metal plate with fixed terrestrial scanning equipment, staff mounted RTK unique permanent identifier equipment is proposed to be adopted requiring a label. grid-based survey approach throughout the nominated extents. • To acquire broader photogrammetry survey information, an RPA (drone) is proposed to be utilised. • Works are to be undertaken in accordance with Work Health and Safety requirements (Chapter 1 of the Operations Manual Volume 1: Station and Field), Environmental Protection and Management requirements (Chapter 2 of the Operations Manual Volume 1: Station and Field), Aviation Standard Operating Procedures (Operations Manual Volume 5)

MARCH 2021 74 INITIAL ENVIRONMENTAL EVAULATION 2021-22 FIELD SEASON

No. Activity Description Objective Locations Number of Frequency of Activity Transport method Equipment to be used Method to be used sites

• 17 • Hydrographic • Fixing the location of work • Acquisition of offshore, • Marchants Landing, • Various • Daily throughout the • Deployed by • Real Time Kinematic Global • Following safety inductions and briefings, Survey areas and characterising nearshore and waterbody coastal areas of Davis 2021/2022 Summer field manned or Positional System, single hydrographic survey equipment comprising marine substrate in vicinity survey information on which Station, Davis Link, season unmanned boat beam / multibeam survey single/multibeam echo sounder, is to be mounted to of possible ship to shore the ongoing project Adams Flat and equipment. the IRB infrastructure sites. engineering design can be within existing lakes • IRB and equipment • The IRB will follow a predestined grid transect path established and ephemeral collecting hydrographic data waterbodies • Data will be recoded on site and transferred and processed upon return to shore. • IRB’s operations noting the equipment, transport, operation, and environmental requirements are to be accordance with AAD’s Watercraft Procedures.

• 18 • Removal of rock • Selected samples • To provide essential • Marchants Landing, • Various • Samples to be collected • Voyage 3 / Air • Samples to be prepared for • Geotechnical soil bulk samples x 140 @ up to 25 kg and soil samples collected through additional geotechnical data Davis Station limits, as part of the 2021-2022 transfer transport and loaded into (3,500 kg) from Antarctica excavation, drilling, hand to provide essential baseline Davis Link, Adams field season activities. refrigerated and • Geotechnical hand specimen rock samples x 100 @ sampling, and auguring to information for ongoing Flat, Heidemann Opportunities for RTA of unrefrigerated containers on up to 10 kg (up to 1,000 kg) be transported to Australia design works. Valley and the Ridge samples to be assessed Station as required. • Geotechnical soil and rock core samples up to 3,300 for testing and analyses Site based on operational Containers to be registered linear meters (up to 27,000kg) program and processed as part of • Ground and surface water samples up to 250L in Station logistics procedures total

MARCH 2021 75 INITIAL ENVIONMENTAL EVALUATION 2021-22 FIELD SEASON APPENDIX 2

APPENDIX 2

Table 2 - Alternatives, impacts and mitigation measures No. Activity Alternative to Not doing Activity Wildlife Heritage Geological Protected Direct and Environments Mitigation Measures and Plans Activity & Values Importance Areas indirect impacts impacted Consequences of activity (Temporary during works) 1 Site Access and Sites of project A less robust outcome with Transitory birds N/A Undefined N/A Ground • Coastal ice-free • Visual inspection of proposed alignment or sites impacted by activities to assess Preparation geotechnical interest substantial increased (Adelie’s) and seals disturbance areas potential impacts native wildlife. Field crew to be trained on habitat indicators with on- will not be accessible design, construction (Elephant Seals) known Potential impacts • Geology going support provided by on station Environmental Officer- Wildlife without helicopter delivery and program to travel over ground associated with • Ecological • Works are to be sequenced and scaled to minimise environmental impact where support introducing schedule, cost risks and through the areas. to native wildlife communities possible additional uncertainties. • Wilderness and • Pre and post work photography to assist in the recording of visual remediation environmental Skuas, Snow Petrels aesthetic values conditions impacts associated and Wilson's Storm • Works to comply with AAD Wildlife Approach Guideline distances, with increased Petrels known to fly • Giant petrels and albatrosses — 100m aviation emissions, throughout the area. • Breeding/moulting emperor penguin — 50m and greater • All other breeding/moulting birds and seals — 15m operational risk • Non-breeding seal or bird — 5m • All vehicles — 200m from all wildlife • Should wildlife approach the works site during drilling, works are to proceed under caution and are to stop should there be a potential for harm

2 Geotechnical Blasting in situ to A less robust outcome with Transitory birds N/A Undefined N/A Ground • Coastal ice-free • Visual inspection of proposed alignment or sites impacted by activities to assess Borehole Drilling. investigate substantial increased (Adelie’s) and seals disturbance. areas potential impacts native wildlife. Field crew to be trained on habitat indicators with on- subsurface, which is design, construction (Elephant Seals) known Noise (~90dB in • Geology going support provided by on station Environmental Officer- Wildlife deemed unacceptable delivery and program to travel over ground near vicinity) - • Ecological • Pre and post work photography to assist in the recording of visual remediation environmentally. schedule, cost risks and through the areas. intermittent communities conditions Remote sensing has uncertainties. while drilling and • Wilderness and • Works to comply with AAD Wildlife Approach Guideline distances, been considered; Skuas, Snow Petrels will depend on aesthetic values • Giant petrels and albatrosses — 100m however, this method and Wilson's Storm borehole depth • Breeding/moulting emperor penguin — 50m does not provide any Petrels known to fly and materials • All other breeding/moulting birds and seals — 15m physical data required throughout the area. encountered. • Non-breeding seal or bird — 5m for rock strength or Potential impacts • All vehicles — 200m from all wildlife engineering design associated with • Should wildlife approach the works site during drilling, works are to proceed under requirements. to native wildlife caution and are to stop should there be a potential for harm by ground • The drilling equipment and methodology has been proposed on the basis to minimise disturbance time required at each location and to minimise environmental impacts • Drilling additives are only to be used where required and in minimal volumes to achieve project objectives • Drilling rig has been mounted internally within a bespoke drilling container to reduce ambient noise levels • Completed boreholes to be remediated at completion of field season unless used for longer-term monitoring. • Boreholes with downhole instrumentation installed are proposed to be remediated upon completion of their operable use. • Standard practice for boreholes not used for monitoring will be sealed / capped at surface to reduce potential for environmental impacts.

MARCH 2021 76 INITIAL ENVIONMENTAL EVALUATION 2021-22 FIELD SEASON APPENDIX 2 No. Activity Alternative to Not doing Activity Wildlife Heritage Geological Protected Direct and Environments Mitigation Measures and Plans Activity & Values Importance Areas indirect impacts impacted Consequences of activity (Temporary during works) 3 Supply of water Reliance of field team Drilling cannot be achieved Transitory birds N/A Undefined N/A Ground • Coastal ice-free • Systems are put in place to recirculate the drilling fluids to minimise the requirement to drill sites to carry water to drill without a water source to (Adelie’s) and seals disturbance areas for resources, reduce vehicle emissions associated with movements and facilitate the (seawater/ sites, which would lubricate and cool the drill (Elephant Seals) known • Geology management of drilling induced waste. meltwater). not deliver sufficient bit to travel over ground • Ecological • Waste management procedures to be in accordance with AAD’s Waste Management water at the rate through the areas. communities Guidelines . required and A less robust result with • Wilderness and • Seawater is proposed to be sourced from Prydz Bay, Heidemann Bay, West Bay and introduce manual increased risk of not being Skuas, Snow Petrels aesthetic values Abatus Bay in addition to within Davis Station Limits where practicable to minimise handling risks. able to make an informed and Wilson's Storm transportation distances and frequencies The use of imported recommendation or Petrels known to fly • All ground disturbance to be remediated upon completion of works or man-made fresh provide sufficient ground through the area. • Water storage tanks (IBC’s) will be removed from site upon completion of works water has been data for engineering design discounted do to the leading to increased associated design, construction environmental delivery and program impacts. No schedule. cost risks and alternatives. uncertainties. 4 Borehole There are no known There are no known Transitory birds N/A Undefined N/A Ground • Coastal ice-free • Data will be regularly downloaded from the instrumently to minimise impacts to instrumentation alternatives to collect alternatives to collect data (Adelie’s) and seals disturbance areas ground disturbance and native fauna monitoring data from depth from depth without the (Elephant Seals) known • Geology • Ground disturbance to be visually remediated upon completion of works with without the use of use of instrumentation. to travel over ground • Ecological photographic records documented. instrumentation. Impacts to project include through the areas. communities • Removal of instrumentation at the end of their operable use Impacts to project lack of data impacting include lack of data engineering design and Skuas, Snow Petrels impacting engineering construction methodology and Wilson's Storm design and adversely impacting Petrels known to fly construction program, cost, and through the area. methodology environmental outcomes adversely impacting program, cost, and environmental 5 Temporary Aoutcomes different type of No shelter provision is a Transitory birds N/A Undefined N/A Ground • Coastal ice-free • Visual inspection of proposed alignment or sites impacted by activities to assess shelter tent or a small safety issue for field team, (Adelie’s) and seals disturbance areas potential impacts native wildlife. Field crew to be trained on habitat indicators with on- installation shipping container so not providing (Elephant Seals) known Potential impacts • Geology going support provided by on station Environmental Officer- Wildlife could provide similar emergency shelter or to travel over ground associated with • Ecological • Pre and post work photography to assist in the recording of visual remediation temporary shelter suitable resting place through the areas. to native wildlife communities conditions (alternative tents increases risks • Wilderness and • Works to comply with AAD Wildlife Approach Guideline distances, would be sufficient, Skuas, Snow Petrels aesthetic values • Giant petrels and albatrosses — 100m but a container may and Wilson's Storm • Breeding/moulting emperor penguin — 50m be impractical and Petrels known to fly • All other breeding/moulting birds and seals — 15m cause environmental through the area • Non-breeding seal or bird — 5m damage). • All vehicles — 200m from all wildlife • Should wildlife approach the works site during drilling, works are to proceed under caution and are to stop should there be a potential for harm • The drilling equipment and methodology has been proposed on the basis to minimise time required at each location and to minimise environmental impacts • Ensure access to shelter is not within soft ground which may lead to further ground disturbance. • Ensure any ground disturbance is visually remediated upon completion of works.

MARCH 2021 77 INITIAL ENVIONMENTAL EVALUATION 2021-22 FIELD SEASON APPENDIX 2 No. Activity Alternative to Not doing Activity Wildlife Heritage Geological Protected Direct and Environments Mitigation Measures and Plans Activity & Values Importance Areas indirect impacts impacted Consequences of activity (Temporary during works) 6 Hand-Augured Drilling, excavator A less robust result with Transitory birds N/A Undefined N/A Ground • Coastal ice-free • Visual inspection of proposed alignment or sites impacted by activities to assess boreholes test pit excavation is increased risk of not being (Adelie’s) and seals disturbance areas potential impacts native wildlife. Field crew to be trained on habitat indicators with not always practical able to make an informed (Elephant Seals) known Potential impacts • Geology ongoing support provided by on station Environmental Officer- Wildlife due to access or recommendation or to travel over ground associated with • Ecological • Pre and post work photography to assist in the recording of visual remediation location constraints. provide sufficient ground through the areas. to native wildlife communities conditions data for engineering design • Wilderness and • Works to comply with AAD Wildlife Approach Guideline distances, leading to increased Skuas, Snow Petrels aesthetic values • Giant petrels and albatrosses — 100m design, construction and Wilson's Storm • Breeding/moulting emperor penguin — 50m delivery and program Petrels known to fly • All other breeding/moulting birds and seals — 15m schedule. cost risks and through the area • Non-breeding seal or bird — 5m uncertainties. • All vehicles — 200m from all wildlife • Should wildlife approach the works site during drilling, works are to proceed under caution and are to stop should there be a potential for harm • Boreholes to be capped or backfilled with unsampled spoil to prevent objects or wildlife from falling into holes. • Ground to be raked and smoothed to eliminate evidence of activities.

7 Test pit Hand digging or Geotechnical information Transitory birds N/A Undefined N/A • Ground • Coastal ice-free • Visual inspection of proposed alignment or sites impacted by activities to assess excavation (30T drilling to gather would be limited to pits (Adelie’s) and seals disturbance areas potential impacts native wildlife. Field crew to be trained on habitat indicators with on- excavator) same information dug on existing tracks only, (Elephant Seals) known • Potential • Geology going support provided by on station Environmental Officer- Wildlife shallow sampling and to travel over ground impacts • Ecological • Pre and post work photography to assist in the recording of visual remediation geophysical surveys. Data through the areas. associated with communities conditions would need to be to native wildlife • Wilderness and • Works to comply with AAD Wildlife Approach Guideline distances, extrapolated to the areas Skuas, Snow Petrels aesthetic values • Giant petrels and albatrosses — 100m for development, leading and Wilson's Storm • Wildlife • Breeding/moulting emperor penguin — 50m to risks in understanding Petrels known to fly entrapment • All other breeding/moulting birds and seals — 15m the substrate properties through the area • Non-breeding seal or bird — 5m used to inform project • All vehicles — 200m from all wildlife design. • Should wildlife approach the works site during drilling, works are to proceed under caution and are to stop should there be a potential for harm • Minimum area to be excavated to achieve project objectives. • Digging with excavator bucket only, rock breaking is not required • Test pits will be reinstated with the excavated material in a “last out, first in approach”. 8 Test pit Several boreholes Inadequate data on Transitory birds N/A Undefined N/A • Ground • Coastal ice-free • Visual inspection of proposed alignment or sites impacted by activities to assess excavation – 3T adjacent to each subsurface soil properties (Adelie’s) and seals disturbance areas potential impacts native wildlife. Field crew to be trained on habitat indicators with on- excavator other in order to to aid in potential (Elephant Seals) known • Potential • Geology going support provided by on station Environmental Officer- Wildlife obtain appropriate engineering design leading to travel over ground impacts • Ecological • Pre and post work photography to assist in the recording of visual remediation volume of soil for to a less robust result with through the areas. associated with communities conditions analyses, leading to increased risk of not being to native wildlife • Wilderness and • Works to comply with AAD Wildlife Approach Guideline distances, increase to project able to make an informed Skuas, Snow Petrels aesthetic values • Giant petrels and albatrosses — 100m program recommendation or and Wilson's Storm • Wildlife • Breeding/moulting emperor penguin — 50m provide sufficient ground Petrels known to fly entrapment • All other breeding/moulting birds and seals — 15m data for engineering design through the area • Non-breeding seal or bird — 5m leading to increased • All vehicles — 200m from all wildlife design, construction • Should wildlife approach the works site during drilling, works are to proceed under delivery and program caution and are to stop should there be a potential for harm schedule. cost risks and • Minimum area to be excavated to achieve project objectives. uncertainties • Digging with excavator bucket only, rock breaking is not required • Test pits will be reinstated with the excavated material in a “last out, first in approach”.

MARCH 2021 78 INITIAL ENVIONMENTAL EVALUATION 2021-22 FIELD SEASON APPENDIX 2 No. Activity Alternative to Not doing Activity Wildlife Heritage Geological Protected Direct and Environments Mitigation Measures and Plans Activity & Values Importance Areas indirect impacts impacted Consequences of activity (Temporary during works) 9 Test pit Digging by excavator, Inadequate data on Transitory birds N/A Undefined N/A • Ground • Coastal ice-free • Visual inspection of proposed alignment or sites impacted by activities to assess excavation - however machinery subsurface soil properties (Adelie’s) and seals disturbance areas potential impacts native wildlife. Field crew to be trained on habitat indicators with on- Manual can only be deployed to aid in potential (Elephant Seals) known • Potential • Geology going support provided by on station Environmental Officer- Wildlife by self-drive or engineering design leading to travel over ground impacts • Ecological • Pre and post work photography to assist in the recording of visual remediation helicopter. to a less robust result with through the areas. associated with communities conditions increased risk of not being to native wildlife • Wilderness and • Works to comply with AAD Wildlife Approach Guideline distances, able to make an informed Skuas, Snow Petrels aesthetic values • Giant petrels and albatrosses — 100m recommendation or and Wilson's Storm • Wildlife • Breeding/moulting emperor penguin — 50m provide sufficient ground Petrels known to fly entrapment • All other breeding/moulting birds and seals — 15m data for engineering design through the area • Non-breeding seal or bird — 5m leading to increased • All vehicles — 200m from all wildlife design, construction • Should wildlife approach the works site during drilling, works are to proceed under delivery and program caution and are to stop should there be a potential for harm schedule. cost risks and • Minimum area to be excavated to achieve project objective. uncertainties • Test pits will be reinstated with the excavated material in a “last out, first in logged/mapped approach”.

10 • Introduced • Consideration as to • Drilling without additives Transitory birds N/A Undefined N/A Introduction on • Coastal ice-free • MSDS’s of all material provided to AAD Environmental Management Team for materials the use of seawater / and salts cannot guarantee (Adelie’s) and seals non-native areas require prior to procurement to identify prohibited materials or those with high associated with meltwater only, the borehole will not (Elephant Seals) known materials • Geology environmental impact potential drilling without the use of become unstable (leading to travel over ground including PVC • Ecological • Equipment and materials to subjected to AADs pre-deployment bio-security process drilling additives and to potential collapse and through the areas. plastics and communities co-ordinated by AAD’s Supply Services Team salts has been greater environmental drilling additives • Additives are only to be used where necessary, in minimal volumes required to meet assessed as an impacts), facilitate Skuas, Snow Petrels project objectives. alternative recovery of representative and Wilson's Storm • Drilling fluids are to be recirculated to minimise the quantity of drilling additives • Imported or man- soil and rock and remain Petrels known to fly required to complete the works made fresh water has unfrozen at depth through the area. • Discharge of excess drilling fluid to be to the marine environment been discounted do • Project impacts include a • Nomination of offset distances to lakes and waterbodies, with proposed works timing to the associated less robust result with controls to minimise potential contamination impacts environmental increased risk of not being • Consideration of PVC use and minimised cutting requirements to prevent impacts. able to make an informed microplastic contamination recommendation or provide sufficient ground data for engineering design leading to increased design, construction delivery and program schedule. cost risks and uncertainties.

11 Surface Tactile assessment of An absence of in situ data Transitory birds N/A Once at each test N/A • Ground • Coastal ice-free • Visual inspection of proposed sites impacted by activities to assess potential impacts geotechnical soil strength can lead to conservative (Adelie’s) and seals pit disturbance areas native wildlife. Field crew to be trained on habitat indicators with ongoing support testing. (Dynamic properties at depth engineering design (Elephant Seals) known • Potential • Geology provided by on station Environmental Officer- Wildlife Cone cannot be assessed parameters leading to to travel over ground impacts • Ecological • Pre and post work photography to assist in the recording of visual remediation Penetrometer from surface greater impacts to the through the areas. associated with communities conditions Testing) environment and native to native wildlife • Works to comply with AAD Wildlife Approach Guideline distances, flora and fauna Skuas, Snow Petrels • Giant petrels and albatrosses — 100m and Wilson's Storm • Breeding/moulting emperor penguin — 50m Petrels known to fly • All other breeding/moulting birds and seals — 15m through the area. • Non-breeding seal or bird — 5m • All vehicles — 200m from all wildlife • Should wildlife approach the works site, works are to proceed under caution and are to stop should there be a potential for harm

MARCH 2021 79 INITIAL ENVIONMENTAL EVALUATION 2021-22 FIELD SEASON APPENDIX 2 No. Activity Alternative to Not doing Activity Wildlife Heritage Geological Protected Direct and Environments Mitigation Measures and Plans Activity & Values Importance Areas indirect impacts impacted Consequences of activity (Temporary during works) 12 Geological Use of remotely Collection of inadequate Transitory birds N/A Undefined N/A • Ground • Coastal ice-free • Pre and post work photography to assist in the recording of visual remediation mapping and sensed imagery to data, leading to a less (Adelie’s) and seals disturbance areas conditions, if required testing map geology and robust result with (Elephant Seals) known • Potential • Geology • Works to comply with AAD Wildlife Approach Guideline distances, geomorphological increased risk of not being to travel over ground impacts • Ecological • Giant petrels and albatrosses — 100m observations lacks able to make an informed through the areas. associated with communities • Breeding/moulting emperor penguin — 50m detail and cannot be recommendation or to native wildlife • All other breeding/moulting birds and seals — 15m relied on in isolation provide sufficient ground Skuas, Snow Petrels • Non-breeding seal or bird — 5m from ground data. data for engineering design and Wilson's Storm • All vehicles — 200m from all wildlife leading to increased Petrels known to fly design, construction through the area delivery and program schedule. cost risks and uncertainties.

13 Geophysical Estimates only. Lack of data leading to a Transitory birds N/A Undefined N/A • Ground • Coastal ice-free • Visual inspection of proposed sites impacted by activities to assess potential impacts Survey Without the less robust result with (Adelie’s) and seals disturbance areas native wildlife. Field crew to be trained on habitat indicators with ongoing support collection of increased risk of not being (Elephant Seals) known • Potential impacts • Geology provided by on station Environmental Officer- Wildlife geophysical data able to make an informed to travel over ground associated with • Ecological • Pre and post work photography to assist in the recording of visual remediation ground conditions recommendation or through the areas. to native wildlife communities conditions and cannot be provide sufficient ground • Works to comply with AAD Wildlife Approach Guideline distances, modelled to assist in data for engineering design Skuas, Snow Petrels • Giant petrels and albatrosses — 100m the project design leading to increased and Wilson's Storm • Breeding/moulting emperor penguin — 50m design, construction Petrels known to fly • All other breeding/moulting birds and seals — 15m delivery and program through the area • Non-breeding seal or bird — 5m schedule, cost risks and • All vehicles — 200m from all wildlife uncertainties • Should wildlife approach the works site, works are to proceed under caution and are to stop should there be a potential for harm • All equipment will be cleaned prior to use to minimise the potential for contamination 14 Near-surface Estimates used to Lack of data leading to a Transitory birds N/A Undefined N/A • Ground • Coastal ice-free • Visual inspection of proposed sites impacted by activities to assess potential impacts Water Flow calculate snow/water less robust result with (Adelie’s) and seals disturbance areas native wildlife. Field crew to be trained on habitat indicators with ongoing support Monitoring. processes re melt increased risk of not being (Elephant Seals) known • Potential • Geology provided by on station Environmental Officer- Wildlife rates and able to make an informed to travel over ground impacts • Ecological • Pre and post work photography to assist in the recording of visual remediation groundwater flow recommendation or through the areas. associated communities conditions rates. Without this provide sufficient ground with to native • Works to comply with AAD Wildlife Approach Guideline distances, data surface water data for engineering design Skuas, Snow Petrels wildlife • Giant petrels and albatrosses — 100m movement cannot be leading to increased and Wilson's Storm • Breeding/moulting emperor penguin — 50m modelled for project design, construction Petrels known to fly • All other breeding/moulting birds and seals — 15m design and may delivery and program through the area • Non-breeding seal or bird — 5m introduce risk schedule, cost risks and • All vehicles — 200m from all wildlife uncertainties • Should wildlife approach the works site, works are to proceed under caution and are to stop should there be a potential for harm • Temporary holding basins, where required, are to be backfilled upon completion of the works 15 Lake and Estimates only. Lack of data leading to a Transitory birds N/A Undefined N/A • Ground • Coastal ice-free areas • All equipment will be cleaned prior to use to minimise the potential for Waterbody level Without the less robust result with (Adelie’s) and seals disturbance • Geology contamination monitoring collection of water increased risk of not being (Elephant Seals) known • Potential impacts • Ecological • Photographs taken prior to activity will be used to assist in remediation. level data, water able to make an informed to travel over ground associated with communities • Following installation, visual observations will be base from the shoreline movement, and levels recommendation or through the areas. to native wildlife cannot be modelled provide sufficient ground to assist in the project data for engineering design Skuas, Snow Petrels design leading to increased and Wilson's Storm design, construction Petrels known to fly delivery and program through the area schedule, cost risks and uncertainties

MARCH 2021 80 INITIAL ENVIONMENTAL EVALUATION 2021-22 FIELD SEASON APPENDIX 2 No. Activity Alternative to Not doing Activity Wildlife Heritage Geological Protected Direct and Environments Mitigation Measures and Plans Activity & Values Importance Areas indirect impacts impacted Consequences of activity (Temporary during works) 16 Terrestrial Survey Site recording with Imprecise locations Transitory birds N/A Undefined N/A • Ground • Coastal ice-free • Works to comply with AAD Wildlife Approach Guideline distances, hand- held GPS recorded for essential (Adelie’s) and seals disturbance areas • Giant petrels and albatrosses — 100m devices, provides an information in potential (Elephant Seals) known • Potential • Breeding/moulting emperor penguin — 50m accuracy to within 5 engineering design and to travel over ground impacts • All other breeding/moulting birds and seals — 15m m, which for the potential environmental through the areas. associated with • Non-breeding seal or bird — 5m purpose of design is impact assessments. to native wildlife • All vehicles — 200m from all wildlife not deemed Skuas, Snow Petrels • Should wildlife approach the works site, works are to proceed under caution and are acceptable and Wilson's Storm to stop should there be a potential for harm Petrels known to fly • Ensure rock bolts, for the creation of survey benchmarks, are installed in bedrock through the area only, with a minimal number of sites required

17 Hydrographic • Estimates from • Insufficient data extent Fish, plankton, N/A Undefined N/A N/A • Shallow marine • Works to be undertaken in accordance with the environmental requirements for Survey existing data is not and accuracy for echinoderms, benthic watercraft documented as part of the AAD Watercraft Operating Procedure. deemed sufficiently infrastructure design microorganisms etc. • Works to comply with AAD Wildlife Approach Guideline distances accurate for • Least possible hours spent on the activity, while collecting sufficient data for the infrastructure design project. and could lead to issues with construction and design. • 18 Removal of rock Performing the Lack of data leading to a N/A N/A Undefined N/A N/A • Coastal ice-free • Amount of material removed from Antarctica will be the minimum possible to meet and soil samples analyses in situ or at less robust result with areas project requirements from Antarctica. Davis Station, is not increased risk of not being • RTA material to be subjected to the required bio-security screening and handling deemed practical due able to make an informed processes to size of equipment recommendation or required, sensitivities, provide sufficient ground cost, and time data for engineering design available. leading to increased design, construction delivery and program schedule, cost risks and uncertainties

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