Woodside all set for ops at Australian gas project

Australian energy giant Woodside has received a stamp of approval from the country’s offshore regulator for an environment plan (EP), covering seabed intervention and trunkline installation activities at a project off the coast of Australia.

Scarborough FPU; Source: Woodside

The National Offshore Petroleum Safety and Environmental Management Authority (NOPSEMA) accepted Woodside’s environment plan in December 2023, proposing to undertake seabed intervention and trunkline installation activities in Commonwealth waters for the Scarborough development, located in production license WA-32-PL off Western Australia.

According to Woodside, the activities run from the Commonwealth–state waters boundary around 32 km north of Dampier to the Scarborough gas field located in title block WA-61-L, about 375 km west-northwest of the Burrup Peninsula. The approximate water depth for the activities is 32 m – 1400 m. The Australian firm’s earliest anticipated activity start date is 4Q 2023 pending approvals, vessel availability, and weather constraints.

Moreover, the estimated activity duration is 24 months across multiple campaigns. The eastern end of the trunkline route overlaps with the Pilbara Port Authority Dampier Port Limits. The trunkline corridor runs through the Montebello Marine Park – Multiple Use Zone (Cth), close to the northern boundary.

Woodside’s operational area includes the proposed trunkline from the Scarborough FPU, around 430 km northwest of the Burrup, to the state waters boundary and 1.5 km on either side of the proposed trunkline centerline to allow for the movement and positioning of vessels.

The Australian player explains that this also includes Spoil Ground 5A, which is approximately 300 m wide and runs about 17 km from the state waters boundary and includes the Offshore Borrow Ground. In this location, sand will be sourced, which is located to the north of the Dampier Marine Park Habitat Protection Zone and 20 km to the east of the proposed trunkline route. A minimum 250 m buffer from the Dampier Marine Park boundary will be in place.

Furthermore, Woodside outlines that the vessels included in the activity encompass trailing suction hopper dredge (TSHD), offshore construction vessel (OCV), rock installation vessel (RIV), pipelay vessel (PV) multi-joint operation, shallow water lay barge (SWLB), anchor handling vessel/tug, pipe supply vessels, survey vessels, support vessels, and fuel bunkering vessels.

Located approximately 375 km off the coast of Western Australia, the Scarborough field’s development will include the installation of a floating production unit with eight wells drilled in the initial phase and thirteen wells drilled over the life of the field. The gas from the Scarborough field will be processed at the Pluto LNG facility, where the company is constructing Pluto Train 2.

Woodside is also the operator of the Pluto Train 2 joint venture and holds a 51% participating interest. The reservoir contains less than 0.1% carbon dioxide and the gas will be transported for processing at Pluto LNG through a new trunkline of approximately 430 km. The final investment decision was made in November 2021 and the first LNG cargo is targeted for 2026.

More drilling work on the horizon

Last month, Woodside got the go-ahead for its Scarborough drilling and completions environment plan, including drilling activities for up to ten development wells in WA-61-L in Commonwealth waters, about 374 km west-northwest of Dampier, Western Australia. The closest landfall to the petroleum activities program is the North West Cape, about 226 km south-south-east at its nearest point.

The EP includes drilling and subsea tree installation activities for eight planned development wells and the potential for a further two additional contingency wells. The Australian giant may also need to undertake intervention, workover, or re-drill activities at the wells. In addition, subsea inspection, monitoring, maintenance, and subsea infrastructure repair activities may be undertaken. This work will be carried out using either a DP MODU or a moored MODU, a subsea installation vessel, and support vessels.

The activity is planned to take place anytime within a five-year window beginning in 2H 2023. The drilling and completions for the development wells are expected to take about 50-60 days per well to complete while subsea inspection, monitoring, maintenance, and repair activities may be conducted intermittently and over short durations near installed subsea infrastructure.

These activities will be conducted 24 hours per day, seven days per week, however, the timing and duration of these activities are subject to change due to project schedule requirements, rig and vessel availability, weather, and unforeseen circumstances.