Santos proposes to drill up to 12 wells (exploration and/or appraisal) in permit areas WA-437-P, WA-438-P and WA-541-P located in the Bedout Basin on the North West Shelf (NWS) in water depths of approx. 30 to 110 m.
The permit areas are wholly within offshore Commonwealth waters, approx. 9 km north from the nearest shoreline (Bedout Island), 50 km from the closest mainland point (De Grey River-mouth) and 99 km from Port Hedland.
The drilling activity will be carried out using a jack-up mobile offshore drilling unit (MODU). A Petroleum Safety Zone (PSZ) of 500 m radius will be established around each well location in accordance with the OPGGS Act and be removed once the MODU leaves the area. A 5-year EP validity period is being sought, and the EP assumes drilling activities can take place at any time over that 5 year period.
A summary of activities included in the EP are:
- MODU and vessel movement and commissioning activities (e.g., equipment testing, tank flushing)
- deployment and recovery of jack-up legs
- riserless drilling
- drilling with a closed-circulating fluid system
- installing casing strings
- operation of a blow-out preventer (BOP)
- drilling using water-based drilling fluid systems
- use of lost circulation materials (LCM)
- use and discharge of chemicals and additives for drilling, evaluation, testing and abandonment activities
- well evaluation, including logging-while-drilling, wireline logging, hydrocarbon sampling, vertical seismic profiling (VSP) and coring
- well testing (sampling, clean up, and flaring)
- permanent abandonment (P&A) activities
- side-track drilling, re-drilling sections and re-spud
- general MODU operations including MODU refuelling, the use of support vessels, helicopters and remotely operated vehicles (ROV).
Activities are scheduled to commence in Q3 2021. However, the timing of subsequent activities has not been finalised. Drilling is expected to take approx. 35 to 80 days per well and activities will be conducted 24 hours per day, seven days per week. It is possible that the Activity duration may increase if technical difficulties or interruptions are encountered (e.g., equipment failures, weather, etc). It is envisaged that well activities are conducted over multiple campaigns; i.e., a MODU arriving to drill one or more wells in a period between two and six months, after which the MODU leaves the operational area.