By Melisa Cavcic
Copyright offshore-energy
Cooper Energy (CH), a subsidiary of Cooper Energy that rebranded itself as Amplitude Energy in November 2024, has submitted its environment plan (EP) to the Australian offshore regulator for drilling activities off the coast of Australia.
The National Offshore Petroleum Safety and Environmental Management Authority (NOPSEMA) has confirmed the receipt of Cooper Energy’s Annie 2 development drilling environment plan, which proposes a drilling campaign within the Commonwealth waters of the Otway basin, in the company’s existing license area VIC/P44, approximately 25-40 kilometers off the coast of Peterborough, in a water depth of 56 meters.
The firm’s EP covers the proposed scope of the Annie-2 development drilling activity, including survey, inspection, and maintenance activities, alongside well construction activities, such as development drilling, subsea tree (SST) installation, well-test, completions, and shut-in campaign. These activities will occur within an operational area defined by a temporary 3-kilometer radius around the well site.
This operational area encompasses the outer extent of mooring equipment from the well site, and a 500-meter radius temporary exclusion zone around a mobile offshore drilling unit (MODU) that will undertake the work. Based on the EP, a 500-meter radius long-term petroleum safety zone may be established around the well once it is completed and suspended.
The operational area is north of primary shipping routes, with some Commonwealth and State fishery overlap, and adjacent to the Southern Ocean offshore wind zone. While the MODU and other support vessels may be visible from the coastline once drilling operations are underway, all equipment installed during the campaign will be on the seabed and will not be visible above the sea surface.These activities will be conducted on a 24-hour, seven-day-per-week basis, with the activity proposed to start as early as April 1, 2026. While the drilling campaign is expected to take up to 60 days, excluding environmental and operational delays, well integrity monitoring will be undertaken annually, following completion of drilling, until tie-in, hook-up, and commissioning of the well.
As specified within the EP, the development well will remain shut-in from completion of drilling until the connection via new flowline to existing facilities, currently proposed to occur in Q2 2028. However, the tie-in of the well and future production from the well will be subject to future regulatory approvals and licensing; thus, it is not included within the scope of this EP.
Cooper Energy’s environment plan identifies and evaluates credible environmental impacts and risks associated with the planned activity and ongoing management of the suspended well until Q1 2031. The Otway Basin covers a 155,000-square-kilometer area from Cape Jaffa in South Australia to northwest Tasmania.
While around 80% of the basin is located offshore, 20% is onshore. Amplitude’s interests in the basin are situated onshore in South Australia and both onshore and offshore in Victoria. The firm’s Otway offshore gas fields and facilities are about 30 kilometers off the coast of Port Campbell, in water depths of 60 to 70 meters.
The gas production began in 2006 from the Casino field (Stage 1) with subsequent stages integrating additional fields to supply continuing demand from the domestic market. Amplitude plans to develop additional gas reserves by drilling new wells and connecting them to existing offshore pipelines to transport gas to the Athena gas plant.
