Reliance Industries Limited had in late-August filed a revised field development plan for discoveries Dhirubhai-1 and 3 (D1&D3) in KG-DWN-98/3 cutting gas reserves to 3.10 Trillion cubic feet from 10.03 Tcf approved in 2006.
The company based its reserve downgrade based on data of over three years of production.
The fields hit a peak of 55 million standard cubic metres per day (mmscmd) in August 2010 before the decline set in and are now producing less than 20 mmscmd.
Sources said the Directorate General of Hydrocarbons in its initial comments on the RFDP stated that 'such drastic reduction of reserves is unprecedented and unconvincing.'
DGH, they said, wants RIL and its partners BP plc to support the reserve downgrade with sufficient technical and geological data.
Originally, RIL had in 2004 estimated 3.81 Tcf of reserves in D1&D3, two of the 18 gas finds the company had made in the eastern offshore KG-D6 block. It had proposed an investment of $2.39 billion to produce 40 mmscmd.
The company revised the reserves to 10.03 Tcf primarily on the basis of its assessment of potential resources in area outside the main channel holding D1&D3
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