Introduction
Petrel Field Development
Discovered in 1969, the Petrel field is an undeveloped gas field located in the northern Australian waters of the Joseph Bonaparte Gulf (JBG). The field sits within two adjacent offshore retention leases NT/RL1 and WA-6-R.
Eni is proposing to develop the Petrel field for long term gas production. One concept under evaluation envisages an offshore Petrel gas pipeline that would tie into the existing offshore Blacktip gas export pipeline (GEP) to send Petrel gas and associated minor quantities of condensate onshore to be processed at the Yelcherr Gas Plant (YGP) over a potential operating life of approximately 20 to 30 years.
Field Location
The Petrel field is located in Commonwealth waters, offshore northern Australia within two adjacent retention leases, NT/RL1 and WA-6-R, around 250km west of Darwin in water depths ranging from 92m to 102m.
The retention leases are an estimated 136km to the closest point on the NT coastline, near Wadeye, and around 145km from the closest point on the WA coastline.
Proposed Activities and Timeline
While Eni is in the early stages of the proposed Petrel field development planning, the following activities are proposed to occur over time. Where required, each individual activity will be the subject of a focussed environment plan and consultation process:
- Surveys - geotechnical and geophysical
- Drilling - two production wells in an initial development campaign and up to eight additional wells in future campaigns
- Installation and commissioning of operational infrastructure - Petrel platform, gas export pipeline and subsea equipment
- Operations
- Decommissioning at the end of the field life
- Support activities (over all phases)
All proposed Petrel infrastructure is located in Commonwealth waters.
At the end of the field life, the infrastructure will be decommissioned in accordance with standard industry practice and relevant legislation at the time of decommissioning.
Timing
Petrel field development studies are currently in progress. The actual timing of the proposed Petrel development activities will depend on a number of factors, including the company’s Final Investment Decision (FID), equipment availability and weather conditions. Any construction activities will be subject to the regulator’s acceptance of the Offshore Project Proposal (OPP) and other regulatory approvals. The Petrel field is forecast to have a potential operating life of up to 20 to 30 years. Decommissioning activities will occur at the end of the field life.
Activity Resources
Environment
Petrel Development EMBA
Hydrocarbon spill events have a very low probability of occurrence due to a range of controls that will be implemented on the proposed activities in accordance with standard industry practice.
The environment that may be affected (EMBA) is derived from scientific modelling of different, low probability hydrocarbon spill events. This analysis combines hundreds of modelling simulations during a range of wind and current conditions for each season and informs the risk assessment and spill response planning.
The final EMBA map is the outermost boundary of all the spill events considered. The actual footprint of any single spill event would be smaller than the EMBA. The outermost boundary of the EMBA is based on modelling the accidental release of marine diesel oil (MDO) to the environment in the unlikely event of a vessel collision offshore damaging a vessels internal fuel tank.
The zone of potential impact (ZPI) is smaller than the EMBA and may be representative of an area of biological impact from hydrocarbons.
Refer to NOPSEMA’s news bulletin for information on oil spill modelling.
FAQs
What Is An Offshore Project Proposal (OPP)?
An offshore project proposal is a key project regulatory document to be developed by Eni and submitted to the National Offshore Petroleum Safety and Environmental Management Authority (NOPSEMA). NOPSEMA is Australia’s independent expert regulator for health and safety, structural (well) integrity and environmental management for offshore petroleum and greenhouse gas storage activities in Commonwealth waters, and in coastal waters where regulatory powers and functions have been conferred.
The Petrel Offshore Project Proposal (OPP) will be developed in accordance with the Commonwealth Offshore Petroleum and Greenhouse Gas Storage Act 2006 (OPGGS Act), the Offshore Petroleum and Greenhouse Gas Storage (Environment) Regulations 2023 [OPGGS(E) Regulations] and associated NOPSEMA guidelines. Refer to Offshore project proposal content requirements (NOPSEMA, 2020) and Offshore project proposal decision making (NOPSEMA, 2024).
The OPP would then be submitted to NOPSEMA for its initial assessment, public comment and ultimately for its acceptance. The OPP must be accepted by NOPSEMA before the titleholder can submit more detailed environment plans (EPs) to NOPSEMA for review and acceptance. An accepted EP is required before any Petrel Project field activities can commence.
As a part of the OPP submission, the proponent must demonstrate that potential environmental impacts and risks associated with the project will be managed to acceptable levels. This will allow NOPSEMA to assess the potential environmental impacts and risks of the petroleum activities over the life of the project. The OPP will be open for a public comment period, which assists in identifying environmental values and sensitivities from stakeholders, further ensuring appropriate management of associated impacts and risks.
Why Am I Being Consulted?
Public consultation is a key requirement for an Offshore Project Proposal (OPP) in accordance with the 2023 OPGGS(E) Regulations and the associated OPP Guidance Notes. The degree of stakeholder consultation undertaken prior to the OPP submission, may be beneficial in pre-determining stakeholder feedback for this initial project planning phase.
As a continuation of Eni’s commitment to the region and our ongoing relationship with our stakeholders, Eni is initiating a stakeholder consultation process for the Petrel Development, of which the details will be included in the OPP prior to its submission. During this process, Eni acknowledges the consultation fatigue that may impact our stakeholders and has refined the process according to the feedback from our stakeholders.
A key component of the OPP process is that following submission of the OPP and it being published in NOPSEMA’s website, there will be an additional invitation for public written comments.
