Santos proposes to drill up to seven (7) exploration and/or appraisal wells in the Commonwealth waters within the Bedout Basin.

The Multi-Well Exploration and Appraisal Drilling EP will cover drilling, evaluating, well testing and abandonment activities related to proposed exploration and appraisal drilling. Activities also include geophysical, hydrographic and geotechnical surveys (1-2 weeks at each well location) to gather critical seabed and subsurface data that will enable the safe and accurate placement of a Mobile Offshore Drilling Unit (MODU), to undertake the drilling. The EP for proposed activities will have a validity of five years to allow for the drilling of up to seven (7) exploration and/or appraisal wells across four (4) Operational Areas (OAs).

The wells are proposed to be drilled between Q3 2026 and Q3 2031 using a moored semi-submersible MODU and/or jack-up MODU. The wells will each take approximately 40 to 110 days to drill, including contingency. The wells may be drilled singularly or as part of a campaign of multiple wells. The wells will be drilled within the defined Bedout OAs named Curie, Ara, Wallace and Mestrel/Bancroft, in Exploration Permit Areas WA-541-P, WA-435-P and WA-436-P. The closest OA to the Western Australia mainland (Mestrel/Bancroft) is approximately 123 km north of Port Hedland.

The precise drilling locations within the OAs are not yet defined and it is proposed that until such time, drilling may occur anywhere within a given OA (Figure 1). In some areas, the exact location of future wells is subject to further geological interpretation and engineering studies. The OAs have been defined to allow for drilling exploration opportunities, appraising discovered resources and evaluating nearby prospects if resource aggregation is required.

Activities are scheduled to commence in Q3 2026 subject to obtaining all regulatory/ business approvals and assumes activities may be undertaken at any time of year, over the five-year validity of the EP.

Scheduling of drilling will utilise the following logic:
• maximum of seven exploration or appraisal wells will be drilled.
• drilling campaigns expected to consist of between two and four wells each.
• two drilling campaigns anticipated; however, a third campaign may be required if a jack-up is utilised for the Mestrel / Bancroft prospect.
• drilling campaigns are typically minimum of 12 months apart to allow for evaluation of acquired well data.
• results of the initial exploration wells will inform the quantity, location and objectives of subsequent wells.

There may be more than one exploration well drilled in an OA. If an exploration well is successful, an appraisal well is anticipated to be drilled on the successful prospect 6 to 18 months after the exploration well drilling. Up to four appraisal wells may therefore be drilled following exploration drilling.

For a typical exploration or appraisal well, activity duration is expected to be between approximately 40-110 days continuous well operations (24 hours per day, seven days per week), including rig activities (e.g. placement), drilling and well evaluation and permanent abandonment. The large duration range is linked to the depth, complexity and the well evaluation programme.