Reliance Industries' gigantic gas finds in the Krishna Godavari basin, off the Andhra coast, may hold reserves in excess of 15 trillion cubic feet, more than double the earlier estimate and would need $1.5-2 billion in investment for its development.

"The total inplace reserves in the four discoveries made in the D6 block by RIL so far is 9.46 trillion cubic feet. They have explored only a fraction of the block... even the 15 tcf might be gross understatement," directorate general of hydrocarbons, the government's upstream nodal agency, said on Tuesday.

Speaking at a seminar on 'Deepwater Discoveries,' Avinash Chandra, director general, DGH, said Dhirubhai-1, the first discovery made by RIL in KG-DWN-98/2 block (D6), contains 4.1 tcf of reserves and can produce 40 million standard cubic metres per day of gas in two years time.

"We anticipate the development expenditure would be in the range of $1.5-2.1 billion," he said.

DGH has already approved commerciality of the discovery and RIL, which has till now announced four discoveries in the block - Dhirubhai-1, Dhirubhai-2, Dhirubhai-3 and Dhirubhai-4, would now submit to the government a development programme for the discovery, for approval.

The firm is currently drilling the seventh well in the block where Dhiurbhai-2 is assessed to contain 0.16 tcf of reserves. Dhirubhai-3 is estimated to have 3.5 tcf of reserves, while Dhirubhai-4, on a different structure 10-km away from the previous three finds, is estimated to have 1.7 tcf reserves, Chandra said.

Chandra said the RIL block can produce 80 million standard cubic metres per day of gas.

The consortium of RIL and Niko Resources of Canada (RIL: 90 per cent; Niko 10 per cent) is likely to need about $2 billion for bringing gas to shore which may take up to 2 years from the date of all clearances, he said.

The gas, in the block, is sweet, dry, mostly methane (99.7 per cent methane content).

RIL-Niko consortium has committed investing $145.75 million in the work programme for the KG-DWN-98/3 deep water block in three phases of oil and gas exploration spread over 6-7 years.

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