Publications

The Arun gas-condensate field is one of the giant gas fields in the world. The gas is produced from the Arun limestone, which is a lower Middle Miocene reefal complex. Initial reservoir pressure was over 7100 psig with a bottom hole temperature of 352°F. The field was discovered in late 1971 and production began in May 1977.Environmental considerations in the design and production of the hydrocarbons were primarily focussed on containment of accidental discharges, disposal of produced water and disposal of drilling waste. Because of the high pressures and temperatures encountered during drilling, complex mud systems were required and this paper is a review of some methods for disposing of the drilling waste.The field was developed on a cluster concept comprising 4 clusters of 16 wells each. Individual clusters were encircled with and ",antipollution ditch", which incorporated an API separator to contain accidental discharges of hydrocarbons. Flare pits were installed to handle initial well clean-up and process upsets but otherwise atmospheric emissions are infrequent and minimal.Large waste pits were built in each cluster to hold the drilling waste. These pits have 'been used since shortly after the field's inception and now contain an estimated 180,000 bbls of waste in each of the four pits. They are nearing capacity and an alternate system of waste disposal is required. Furthermore, the space currently occupied by these pits is required for the installation of booster compression prior to the time when the field pressure will have declined to below that of the pipeline.