AWE Limited (AWE) has outlined new information regarding the 2P Reserves and 2C Contingent Resources for the Waitsia gas field after completion of an independent review by Perth-based RISC Operations (RISC).
The Waitsia gas field is located in onshore Permit L1/L2, northern Perth Basin, Western Australia.
An independent review by RISC of the Waitsia gas field estimates gross 2P Reserves of 811 PJ, which is 78% higher than AWE’s previous 2P Reserves estimate at 30 June 2017
– The increase reflects the significantly better than expected reservoir quality, thickness and well deliverability outcomes from the recent drilling and testing program
– The independent assessment is closely aligned with AWE’s internal estimates from work completed to date, which will be finalised by year end after incorporating the most recent data from appraisal operations
– The new gross 2P Reserves estimate is more than double the amount of gas required for the Waitsia Stage 2 project, providing additional options for both increased near term field production and significantly longer field life
– Substantial additional upside is demonstrated by the new gross 3P reserve estimate of 1,220 PJ
The review and evaluation undertaken by RISC (see Table 1) concluded that 2P Reserves for the Waitsia gas field were 78% higher than AWE’s previous estimate as at 30 June 2017 (see Table 2). The RISC work is consistent with AWE’s current internal view of Waitsia Reserves, which will be finalised when the current flow test program and subsequent analysis and evaluation work are complete. AWE anticipates issuing a further update before the end of 2017.
AWE’s CEO and Managing Director, Mr David Biggs, said:
“The independent review of the Waitsia gas field, recently undertaken by RISC, highlights substantially higher recoverable hydrocarbons and additional production potential from the excellent quality conventional reservoirs in the Kingia and High Cliff Sandstones.
“The Waitsia Stage 2 development project is planned to deliver 100 TJ/day for at least 10 years. The additional reserves identified by this review are more than double the reserves required for this project and provide opportunities for significantly increased near term field production and longer field life.
“The recent flow tests at Waitsia-3 (50 MMscf/d) and Waitsia-2 (39 MMscf/d) were exceptional and we are aiming to flow test Waitsia-4 before the end of November. The data from the flow tests and the upgraded view of reserves by RISC will provide further information for potential gas buyers,” Biggs said.
“Waitsia sub-surface appraisal is virtually complete and the FEED process is targeting final tender submissions at the end of November. AWE is working to be in a position to consider a FID by the end of 2017, subject to securing sufficient gas sales agreements,” he concluded.
RISC’s reserves estimates were calculated for conventional reservoir units in the Kingia and High Cliff Sandstones only and excluded the Dongara, Wagina, Irwin River Coal Measures (IRCM) and the associated Senecio, Synaphea and Irwin fields.
Since RISC’s August 2016 estimate, there have been a number of material changes which have resulted in the increase to the reserve estimates. The Waitsia-3 and Waitsia-4 wells were drilled and encountered substantially thicker sections of high quality Kingia reservoir than previously observed. The Waitsia-3 and Waitsia-4 well results enabled a transfer of contingent resources in the Kingia reservoir to the reserves classification. The 3D seismic data volume has been reprocessed and re-depth converted using the new well data. The observed thicker Kingia reservoir and refined depth conversion also resulted in the estimation of greater thickness, rock volume and improved reservoir properties, resulting in a significant increase to the gas initially in-place and recoverable reserves.
The Joint Venture partners in L1/L2 are:
AWE Limited (via subsidiaries) (Operator) 50.0%
Origin Energy Limited (via Lattice Energy) 50.0%
About the Waitsia Gas Field
The northern Perth Basin has been one of Western Australia’s major gas producing regions for more than 50 years. Discovered in September 2014, the Waitsia field is regarded as the largest onshore conventional gas discovery in Australia for the last 40 years and has the capability to supply the domestic market with at least 100 TJ/d for more than 10 years from conventional reservoirs.