Cooper Energy (Sole) Pty Ltd (Cooper) is the Titleholder for Production Licence VIC/L32 (Sole) which is approximately 65 km from Orbost Gas Plant off Victoria’s coast in Bass Strait. Appraisal drilling has previously been undertaken within this lease, and Cooper Energy is now proposing development drilling of two wells – Sole-3 and Sole-4, as well as well abandonment at Sole-2, as part of on-going field development operations within the Sole field.
Activities included in the scope of the Environment Plan (EP) include pre-mooring activities, drilling, well abandonment, well suspension, support vessels, ROV activities and use of helicopters. All activities will be occurring in water depths approximately 125 m. The MODU Ocean Monarch has been engaged for this work scope. Cooper Energy will apply for a 500 m exclusion zone for drilling of the Sole-3 and Sole-4 wells, which will remain in place once wells are suspended.
The MODU will be moored to allow drilling and completion of Sole-3 and Sole-4 without re-positioning anchors (i.e. the MODU will kedge – adjust the anchor chain lengths - between the well locations), noting Sole-3 and Sole-4 are only a short distance (44 m) away from each other. The mooring design may also allow kedging of the MODU to Sole-2, however repositioning anchors may be required; this will be determined when the mooring program is finalised.
Activities are anticipated to commence the first half of 2018. Drilling and abandonment activities, including continency pre-lay of moorings and preparation for Blowout Preventer (BOP) if required, are expected to take approximately 70 days, excluding weather and operational delays. During this period, any of the activities described in the EP may be undertaken, with normal operations conducted 24-hours a day.
Following completion, Sole-3 and 4 will be suspended until the Sole development is ready to receive flow from the reservoir. During this period, any of the activities described in the EP may be undertaken, with normal operations conducted 24-hours a day.
The MODU will be towed to location where it will be moored prior to commencing activities. Anchors may be placed on the seabed and tested by the support vessels prior to the MODU arriving. Eight anchors will be required, with each having a footprint of approximately 30 m2. Each anchor is connected to large chain (83 mm) which runs along the seabed towards the MODU for approximately 1100 m before rising towards the MODU.
The MODU will be supported by two or three anchor handling, tow and support (AHTS) vessels. One vessel will remain on standby and in attendance to the MODU throughout the workover program.