Cooper Energy (CH) Pty Ltd proposes to undertake development drilling within Commonwealth waters of the Otway Basin. Cooper Energy (CH) Pty Ltd is a subsidiary company of the parent company Cooper Energy which was rebranded as Amplitude Energy in November 2024. The Annie 2 development well will be drilled in Cooper Energy’s existing licence area VIC/P44 approximately 25-40 km offshore from Peterborough in a water depth of 56m.

The proposed scope of the Annie-2 development drilling activity covered by this Environment Plan (EP) consists of the following activities:
• Survey, inspection and maintenance activities.
• Well construction activities, including development drilling, subsea tree (SST) installation, well-test, completions, and shut-in campaign.

Planned activities will occur within an operational area defined by a temporary 3 km radius around the well site. The 3km operational area includes the outer extent of mooring equipment from the well site, and a 500 m radius (0.8 km²) temporary exclusion zone around the mobile offshore drilling unit (MODU). A 500 m radius (0.8 km²) 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. During drilling activities, the MODU, supply and other support vessels may be visible from the coastline, similar to other shipping traffic. All equipment installed during the campaign will be on the seabed and will not be visible above the sea surface.

Activities will be conducted on a 24 hour, 7 days per week basis with the activity proposed to commence as early as 1 April 2026. 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.

The development well will remain shut-in from completion of drilling until connection via new flowline to existing CHN facilities currently proposed in Q2 2028. The tie-in of the well and future production from the well will be subject to future regulatory approvals and licencing and is not within the scope of this EP. This EP identifies and evaluates credible environmental impacts and risks associated with the Activity and ongoing management of the suspended well until Q1 2031.