Activity - Van Gogh, Coniston and Novara Drilling and Completions
|Organisation||Santos WA PVG Pty Ltd|
|Project||Van Gogh Coniston Novara Field Developments|
|Submission date||03 November, 2015|
|Acceptance date||22 November, 2016|
|Start date||01 May, 2021|
|Stop date||30 September, 2021|
Chief Environmental Advisor
100 St George's Terrace
PERTH WA 6000
+61 8 6218 7100
In order to maintain and maximise the existing production from the Van Gogh, Coniston and Novara fields, Quadrant Energy proposes to carry out appraisal and production well drilling in Permits WA-35-L and WA-55-L (the Defined Area) using a mobile offshore drilling unit (MODU). At its closest point, the Defined Area is located 32 km from the nearest landfall at North Muiron Island, 41 km from North West Cape and 56 km from Exmouth.
This plan includes the drilling and completion of six infill wells at existing drill centres in permit WA-35-L. Appraisal wells could also be drilled in permit WA-35-L (1 well) and WA-55-L (1 well) and completed for production dependant on exploration success. This plan includes all ancillary activities required to drill and complete a well successfully and safely.
Planned activities include:
Preparation in readiness for MODU operations, for example installation of pre-lay MODU anchors, long baseline (LBL) acoustic transponder array or stand-by mooring for support vessels;
Moving the MODU on and off location;
MODU mooring or dynamically positioning;
MODU commissioning and decommissioning activities;
Manipulation of existing subsea infrastructure, for example moving of Electric/Hydraulic Flying Leads (EHFLs);
Infill production well drilling activities which may be new wells or re-entries of existing wells (slot recovery) and will include horizontally drilled production laterals;
Appraisal well drilling activities which will be new wells;
Testing of wells, for example wireline logging, well testing and vertical seismic profiling (VSP);
Completing of wells contingent on drilling and testing success, for example completing a successful appraisal well ready for tie-in and production;
Well work-over activities, for example for maintaining/replacing down-hole components that are not functioning or to install barriers required for well suspension or abandonment;
Permanent plug and abandonment activities which may include removal of casing, wellhead and subsea tree;
Placing and/or retrieving equipment on the seabed;
Subsea metrology, for example spool metrology; and
General MODU, support vessel, ROV and helicopter operations.
Infrastructure installation activities (other than drilling and completions-related), reservoir production, vessel-based seismic surveys and decommissioning (other than well infrastructure removal associated with a well abandonment) are not included.
Activities are scheduled to commence in Q1 2016 subject to obtaining all regulatory and business approvals and may occur anytime thereafter within the 5-year period from date of acceptance. Impacts and risks have been assessed for all seasons, so not to limit the time of year in which activities described in this plan may occur.
For a typical well, the activity duration is expected to be between 60 to 80 days. It is possible that the activity duration may increase in the case of technical difficulties and interruptions (e.g. breakdowns, wait-on-weather, etc.). It is also possible that well activities may be completed over multiple campaigns, whereby the MODU moves off location for a period of time before returning.