COOPER BASIN NATURAL GAS RESERVES UPGRADED Remaining recoverable gas reserves in the areas held by the Santos Ltd <STOS.S>-led Cooper Basin joint ventures have been upgraded to 2,721.7 billion cubic feet (bcf) from the 2,466 estimated last May, Santos said. The upgrading followed a re-review by consultant <Coles Nikiforuk Pennell Associates> in light of the large number of gas finds since May 1986, Santos said in a statement. This means that total contractual commitments of 2,455.5 bcf to <The Australian Gas Light Co> of New South Wales and the Pipeline Authority of South Australia can be met with spare gas available for sale in South Australia, it said.