Pyxis and Braastad Exploration Drilling
|Submitted by||Woodside Energy Ltd|
|Submission date||23 October, 2014|
|Decision date||09 December, 2014|
|Link to previously accepted EP|
The purpose of the proposed Petroleum Activities Program is to explore for new commercial hydrocarbon resources. The exploration well drilling in WA-404-P (Braastad) is also a commitment under exploration permit area requirements, issued under the Offshore Petroleum Greenhouse Gas Storage Act 2006 (Cwth).
The proposed Petroleum Activities Program is located in production licence WA-34-L (Pyxis) and exploration permit WA-404-P (Braastad) in Commonwealth waters, located approximately 170 and 260 km (respectively) north-west of Dampier and approximately 66 and 137 km (respectively) north, north-west from the nearest shoreline (Montebello Islands).
The exploration wells will be drilled by either a semi-submersible drill rig that is moored or operates under dynamic positioning (DP) or a DP drillship, with associated support vessels.
Key activities are as follows:
Drilling of the top-hole sections using seawater with high viscosity sweeps
Installation and cementing of steel casing in the hole
Installation of the blow out preventer (BOP) on the wellhead and testing
Connection of a marine riser between the BOP and the drill rig/drillship to provide a closed loop system for the recirculation of drilling fluids and drill cuttings from the well to the drill rig/drillship
Drilling of bottom hole sections to the planned depth
Well evaluation using Vertical Seismic Profiling (VSP)
Further installation and cementing of steel casing/liners
On completion, plugging and abandonment of the well.
Drill cuttings generated during drilling of the top hole section will be discharged at the sea bed. For the bottom hole section, once the marine riser has been installed, drill cuttings will be discharged at the sea surface.
The reference drilling fluid case for the Petroleum Activities Program is a water based mud (WBM) drilling fluid system, however, a non-water-based mud (NWBM) drilling fluid system may be required to meet technical requirements for sections of the wells, if identified during detailed well design.
The Petroleum Activities Program is scheduled to commence in 2015. The current drilling sequence plan requires that only one well will be drilled at any given time (i.e. no planned concurrent drilling operations under the EP). The schedule and timeframe may be subject to change due to operational requirements and external influences such as MODU availability, weather conditions and oceanic conditions. The EP has risk assessed the drilling of gas wells throughout the year (all seasons) to provide operational flexibility for mobile offshore drilling unit (MODU) schedule changes and availability.
Note: This information has been extracted from the EP Summary. Please refer to the attached EP Summary for more information.