HARRIET — ONE YEAR FROM APPROVAL TO PRODUCTION

Abstract

The Harriet oilfield is located offshore Western Australia, north of Onslow and west of Dampier, close to the Lowendal islands. The original estimate of oil in place is approximately 60 million barrels and constitutes a truly marginal field development.

A feasibility study comparing various options for production facilities was prepared initially. A conventional eight-legged jacket with well template and two production decks was selected as cost effective with relative ease of design in meeting the environmental criteria. Nearby Varanus Island was chosen as the operations base and storage terminal, with an eight-point conventional spread mooring for the tanker loading export facility.

Environmental Protection Agency and Mines Department approvals were received in May 1985. The state of planning, engineering and pre-ordering was such that the 'A' platform was installed by the end of November some six months after approval; the island storage was ready to accept production by mid-January when the wells were tied in. Production commenced on 18 January 1986, one year and 11 days from participant budget approval, and seven and one-half months after government approvals.

Simultaneously with construction, field extension to the north was proven in August, and approved for development in September. The necessary pipelines to the two satellites 'B' and 'C' were prepared on the island and installed in January 1986. The satellite platform schedule was delayed by industrial action but installation was completed in July and production from the field extension commenced in early September.

Local materials, equipment and contractors were used to the greatest extent possible. A measure of this is that the equivalent of 14 per cent was spent overseas out of a development total of over $150 000 000.