SURFACE FACILITIES FOR OILFIELDS IN THE SOUTH AUSTRALIAN SECTOR OF THE COOPER BASIN

Abstract

Delhi Petroleum Pty Ltd, as operator, has been responsible for the development of eight oilfields in the South Australian sector of the Cooper Basin since 1982. Some of these field developments are economically marginal, hence the need to optimise those aspects of the facilities which impact on the ongoing cost of production and the overall profitability. A phased development approach has evolved over the past three years to reduce the external financing requirements and to improve the certainty of the data used to define the key elements of each project.

For the successful completion of the project a task force approach to project management is utilised, supported by the use of computerised project planning and control systems. Further, it is important to define and agree on the design criteria and philosophy for the project at the commencement, this providing a base by which to measure scope changes, and so that all concerned are working to a common goal.

The use of economic analysis as a decision-making tool during all phases of the project assists the project team to home in on the key objective which is to maximise the project net present value. Comparative economics and sensitivity analysis are used at the conceptual stage to select the preferred development option, e.g. pipeline versus trucking.

The design of surface facilities is dictated by a wide range of criteria including the above development philosophy. The variable nature of these criteria demonstrates that each new field development must normally be engineered individually to ensure the target of maximum net present value can be achieved.

The Gidgealpa Crude Oil Development Project demonstrates the effectiveness of the above methodology and philosophies. The field was discovered in August 1984, and early production and trucking of oil commenced in January 1985 with 374 000 bbls produced prior to commissioning of the pipeline to Moomba in September 1985.