Santos Ltd (Santos) and Bonaparte Gas and Oil Pty Ltd are joint titleholders of petroleum retention lease WA-27-R, in the Bonaparte Basin, approximately 300 km west-southwest of Darwin and approximately 100 km offshore from the Western Australian coast.

The Tern-1 well was drilled in WA-27-R in 1971 targeting potentially commercial gas resources. The well was plugged and abandoned in the same year and now Santos proposes to leave the wellhead permanently in-situ.

The defined petroleum activity for this EP comprises of leaving the wellhead in-situ in perpetuity. No further operations or works are required. No future wellhead surveys or monitoring is planned.

The petroleum activity ends upon acceptance of the EP by National Offshore Petroleum Safety and Environmental Management Authority (NOPSEMA), and on submission and acceptance of the notifications as required under Regulation 29 (end of activity) and Regulation 25A (end of EP) of the Offshore Petroleum and Greenhouse Gas Storage (Environment) Regulations 2009 (OPGGS(E)R 2009).

At process end, Santos will have made arrangements satisfactory to NOPSEMA for leaving the wellhead (property) in-situ in perpetuity compliant to Section 270(3)(ii) of the Offshore Petroleum and Greenhouse Gas Storage Act 2006.