QE-91-BI-20003 Asset Removal Operations Environment Plan Summary PROJECT / FACILITY Asset Removal/VI Hub REVIEW INTERVAL (MONTHS) No Review Required SAFETY CRITICAL DOCUMENT NO Santos Ltd | Asset Removal Operations Environment Plan Summary Revision History Rev Rev Date Author / Editor Amendment A 12/02/2019 Jacobs/Santos Draft for Santos review 0 14/02/2019 Jacobs/Santos Issued for external use 1 04/08/2019 Jacobs/Santos Re-issued for external use 2 31/10/2019 Santos Re-issued for external use Contents 1. Introduction .............................................................................................................................................. 5 1.1 Operator .......................................................................................................................................... 5 1.2 Purpose ............................................................................................................................................ 5 2. Activity Location ...................................................................................................................................... 5 2.1 Location ........................................................................................................................................... 5 2.2 Operational Area .............................................................................................................................. 8 2.3 Schedule ........................................................................................................................................... 8 3. Description of the Activity ...................................................................................................................... 8 3.1 Planned Activity ............................................................................................................................... 8 3.1.1 Surveys .................................................................................................................................................. 8 3.1.2 Preparatory works ................................................................................................................................. 9 3.1.3 Structure removal .................................................................................................................................. 9 3.1.4 Subsea cap ............................................................................................................................................. 9 3.1.5 Structure debris removal ..................................................................................................................... 10 3.1.6 Structure disposal ................................................................................................................................ 10 3.2 Vessel Operations ........................................................................................................................... 10 3.3 Logistics Support ............................................................................................................................ 10 4. Environment Description ...................................................................................................................... 10 4.1 Regional Setting ............................................................................................................................. 11 4.2 Marine Environment within EMBA ................................................................................................. 11 4.2.1 Marine habitats ................................................................................................................................... 11 4.2.2 Marine fauna ....................................................................................................................................... 15 4.3 Marine Protected Areas .................................................................................................................. 16 4.4 Marine Key Ecological Features ...................................................................................................... 16 4.5 Terrestrial Conservation Reserves................................................................................................... 16 4.6 Cultural Environment ..................................................................................................................... 16 4.7 Socio‐economic Environment ......................................................................................................... 17 5. Stakeholder Consultation ..................................................................................................................... 17 5.1 Ongoing Consultation ..................................................................................................................... 18 5.2 Addressing Consultation Feedback ................................................................................................. 18 6. Environmental Assessment ................................................................................................................. 19 6.1 Overview of Process ....................................................................................................................... 19 6.2 ALARP and Acceptability Evaluation ............................................................................................... 20 6.3 Summary of Impacts and Risks ....................................................................................................... 20 7. Management Approach ......................................................................................................................... 32 8. Hydrocarbon Spill Arrangements ........................................................................................................ 32 9. Contact Details ....................................................................................................................................... 33 10. References ............................................................................................................................................. 34 Santos Ltd | Asset Removal Operations Environment Plan Summary Page 3 Tables Table 2‐1: Santos WA facilities located within State water production licences .............................................. 6 Table 2‐2: Location and direction of offshore facilities to key regional features ............................................. 6 Table 4‐1: Marine habitats identified within the EMBA .................................................................................. 12 Table 4‐2: Description of marine habitats identified for each asset ............................................................... 14 Table 4‐3: Marine fauna within the EMBA ...................................................................................................... 15 Table 4‐4: Marine protected areas within the EMBA ...................................................................................... 16 Table 4‐5: Terrestrial conservation reserves within the EMBA ....................................................................... 16 Table 4‐6: Socio‐economic environment in the vicinity of the EMBA ............................................................. 17 Table 5‐1: Varanus Island ARO stakeholder list ............................................................................................... 18 Table 6‐1: Santos consequence level descriptions .......................................................................................... 20 Table 6‐2: Summary of impact consequence levels associated with planned events .................................... 20 Table 6‐3: Summary of the residual risks associated with unplanned events ................................................ 21 Table 6‐4: Environmental management for planned events .......................................................................... 23 Table 6‐5: Environmental management for unplanned events ...................................................................... 26 Table 8‐1: Credible spill scenarios for the activity ........................................................................................... 32 Figures Figure 2‐1: ARO facility locations ....................................................................................................................... 7 Figure 3‐1: Example of subsea cap layout and dimensions (in mm) ............................................................... 10 Figure 4‐1: Benthic habitats within the EMBA ................................................................................................ 13 Figure 6‐1: Environmental assessment process .............................................................................................. 19 Figure 6‐2: Risk matrix ..................................................................................................................................... 22 Santos Ltd | Asset Removal Operations Environment Plan Summary Page 4 1. Introduction On 27 November 2018, Santos completed its acquisition of Quadrant Energy. This has the effect that Santos Limited is now the ultimate holding company of Quadrant Energy Holdings Pty Ltd and its subsidiaries (which includes the operator in respect of this environment plan, Quadrant Energy Australia Limited, now renamed Santos WA Northwest Pty Ltd (Santos WA) but with the same ABN). Santos WA proposes to opportunistically remove Varanus Island