Once all formalities are completed, the ONGC consortium will spend about Rs 1,700 crore (Rs 17 billion) on developing these three blocks, sources indicated.
Other members of consortium are Oil India, APGIC and NTPC.
As many as 19 exploratory well will be drilled in the three blocks- KG-OSN-2009/1, KG-OSN-2009/2 and KG-OSN-2009/4-put together.
The Oil and gas major won these blocks in the eighth round of NELP conducted in 2009.
"The Ministry of Environment and Forests gave conditional clearance to undertake exploratory drilling in these three blocks.
"Once successful, the total investment required for the full-fledged drilling for three Blocks will be in the range of Rs 1700 crore.
The exploratory drilling will be done in 19 wells," a source told PTI.
In KG-OSN-2009/1Block, ONGC holds 80 per cent stake while Andhra Pradesh Gas Infrastructure Corporation and NTPC hold 10
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