Apache has now drilled five gas discoveries in the permit - Julimar, Julimar East, Brunello and Brulimar, according to Apache president and chief executive officer G Steven Farris.

"Two additional wells are planned on the block in 2008, and we believe the ultimate size of this gas accumulation could be in the range of 2 to 4 trillion cubic feet," he said.

Julimar Southeast-1 was drilled in 502 feet of water about 1.9 miles from Julimar-1, which logged 132 feet of net pay and test-flowed a combined 85 million cubic feet (MMcf) per day from two zones.

"Julimar Southeast-1 encountered both the stratigraphically oldest and structurally deepest gas pay in the field to date," Farris said.

Apache has a 65% stake in the block; Kufpec owns the remaining 35%.

Meanwhile, Apache has had another WA gas find in the WA-13-L production license, which contains the East Spar Field that Apache (55%) holds in partnership with Santos (45%).

The Halyard-1 discovery test-flowed at a peak rate of 68 million cubic feet of gas and 936 barrels of condensate per day from 91 feet of net gas pay in the Cretaceous Halyard sandstone, according to Apache, which operates the block.

Halyard-1 was drilled in 366 feet of water and is on trend with the Apache and Santos-held John Brookes Field, which is producing 240MMcf of gas per day from three wells for the WA domestic market.

Julimar and associated discoveries could be sold into a second train at Woodside's Pluto LNG project, but both the Julimar group of finds and Halyard are likely to be developed for the domestic gas market.

It is believed that Apache's recent WA gas contracts have achieved prices close to international LNG prices.