West Erregulla is an onshore gas field located within exploration permit EP 469 near Perth in Western Australia.
The exploration permit EP 469 is owned by a 50:50 joint venture of Strike Energy and Hancock Prospecting. Strike Energy is the operator of the permit.
The developers are awaiting final environmental approval from the Western Australian Environmental Protection Agency. Gas production from the field is expected to commence by late 2024.
Strike Energy’s gas acceleration strategy, involving the development of its Walyering, Ocean Hill, South and West Erregulla gas fields, was awarded the Lead Agency Service by the Department of Jobs, Tourism, Science and Innovation of Western Australia.
The award will help Strike Energy navigate the approval processes and bring the four fields onstream by 2025, which will support energy security and energy transition for Western Australia.
West Erregulla gas field location
The West Erregulla gas field is located approximately 350km northeast of Perth near Dongara town in Western Australia.
The field lies within the Greater Erregulla region, which includes the South Erregulla gas field in PL24 and is 100% owned and operated by Strike Energy.
Discovery and appraisal details
West Erregulla was discovered by the West Erregulla 2 well, which was drilled in 2019, targeting the Permian-aged Kingia and High Cliffs sandstones.
The well intersected 78m of net pay within the Wagina, Kingia and High Cliff sandstones. A production test conducted on the well in the Kingia sandstone flowed at the rate of 69 million metric standard cubic feet per day (Mmscf/d).
Three appraisal wells, West Erregulla 3 (WE3), West Erregulla 4 (WE4) and West Erregulla 5 (WE5), were drilled between 2020 and 2022 to appraise the reservoir distribution of the field.
The West Erregulla 3 (WE3) well encountered overpressure in the Carynginia shale and had to be suspended in 2021. The well was re-entered in mid-2022 and intersected 38m of net pay. It was produced at the rate of 90Mmscf/d during a production test.
A workover of the WE4 and WE5 wells is proposed to deepen the gas-water contact.
All wells drilled at West Erregulla are planned to be completed as future producers to support the field development.
West Erregulla gas field is estimated to contain proven and probable reserves of 422 petajoules (PJ).
West Erregulla gas field development details
The West Erregulla gas field development plan includes the construction of a flowline gathering network system that will carry the gas from the four existing wells and two new conventional wells to an upstream gas processing facility.
A remote terminal unit, metering and corrosion inhibitor chemical injection system will be installed at each well site. Pigging facilities will be installed for the trunklines and flowlines.
In addition, related infrastructure will be built such as a slug catcher, pigging tie-in points, sump tanks and a common manifold that will terminate at the gas and liquids transfer point.
The produced gas will be supplied to a gas processing facility operated by Australian Gas Infrastructure Operations (AGI Operations).
Two near-field exploration wells are planned to be drilled to determine the size and scale of infrastructure required for the field.
Phase one of the project is expected to produce 87 terajoules daily (TJ/d).
Processing plant and pipeline
The gas processing facility will have a nominal production capacity of 87TJ/d. A 16.5km buried gas pipeline will transport the processed gas to the Dampier to Bunbury Natural Gas Pipeline (DBNGP).
The project includes the development of a custody transfer metering facility at the DBNGP tie-in point.
In addition, supporting infrastructure such as a pig launcher station, a power generation system, a flare system, an incinerator, access tracks, a fire water system, accommodation and office spaces, water treatment facilities and a communications system will be developed.
Gas purchase agreement
Strike Energy signed a gas offtake agreement with CSBP, a fertiliser manufacturer, in August 2020 to supply 100PJ of gas produced from West Erregulla for 11 years.
The produced gas will be delivered at a maximum rate of 25TJ/d upon commencement of production from the field.
Geological and geophysical consulting firm Igesi Consulting was responsible for undertaking reinterpretation of 3D seismic data related to the field.
Drilling and wells servicing company Ensign Energy Services is providing drilling services for the West Erregulla gas field.