D-19 is one of the four satellite gas field whose optimised field development plan (OFDP) was approved in January this year, the DGH wrote.

"Approved OFDP envisaged eight development gas wells with a peak gas production level of 10.30 million standard cubic meters per day," it said.

RIL has till date made 18 gas and one oil find in the KG-DWN-98/3 or KG-D6 block in the Bay of Bengal. Of these, Dhirubhai-1 and 3, the largest of the 18 gas finds, were put on production in April 2009 while MA oil field came into production in September 2008.

D1&D3 have seen output drop from 55 mmscmd peak in August 2010 to 20.06 mmscmd this month as water and sand seaped into wells. High water and sand ingress has forced RIL to shut six out of the 18 wells on the fields.

MA field has seen output drop for the same reasons from over 8 mmscmd to 5.05 mmscmd.

In a separate letter, the DGH advised RIL "to monitor the water/gas ratio closely and adopt suitable measures in case of deviation from the envisaged profile."

The satellite fields are key to RIL reversing the flagging output from the KG-D6 block.

The company had in July, 2008, submitted a FDP to exploit reserves of 1,708 billion cubic feet (bcf) in nine satellite gas discoveries (D-2, D-4, D-6, D-7, D-8, D-16, D- 19, D-22 and D-23) in the D6 block at an estimated capex of USD 5.91 billion. This, the DGH found, was not techno-economically viable.

Thereafter, RIL submitted OPDPF for four satellite (D-2, 6, 9 and 22) gas discoveries on December 19, 2009. A peak gas production rate of 10.30 mmscmd is envisaged from the four where recoverable reserves are estimated at 617 billion cubic meters out of an inplace reserves of 1.343 tcf.

DGH said the OFDP was approved by the KG-D6 block oversight panel, called the Management Committee on January 3 this year.

This envisages commencement of gas supply from mid-2016, it added.

RIL's proposal to invest up to USD 2.338 billion to produce about 15 mmscmd of gas from D-24, or the R-Series gas field in the same block is also pending approval. The field has gross in-place gas reserves of 1.64 tcf.