ONGC rig in grip of major gas leak

MUMBAI, Nov 5: An offshore well of the Oil and Natural Gas Commission (ONGC) has been leaking for the past 10 days. Fearing a major blow-ou...

MUMBAI, Nov 5: An offshore well of the Oil and Natural Gas Commission (ONGC) has been leaking for the past 10 days. Fearing a major blow-out, 70 workmen have been evacuated and the crisis management team of the company is engaged in hectic efforts to prevent an explosion on the jack-up rig Sagar Shakti.

When high pressure in the oil well B-24-2 could not be maintained, it began releasing a jet of gas in a 10-metre plume. Workmen on the rig, located southwest of Bombay High about 120 nautical miles of the mainland, were immediately evacuated. Three attempts by the ONGC to kill the well failed.Workmen say that natural gas spewing out uncontrollably from the top of the rig is now threatening to engulf and blow up the multi-million dollar jack-up drilling rig, Sagar Shakti.

A diving vessel PS III has been kept stand by alongside the rig to prevent a possible blow-out or ignition of the gas jet. Five other offshore support vessels are spraying water on the well mouth round-the-clock to prevent a massive explosion due to the high friction.

Story continues below this ad

Confirming the incident on the well, ONGC Public Relations Officer E M Reddy told The Indian Express that final stubbing operations will be completed in the next 10 to 15 days. “The operation will cost around Rs 40 to Rs 60 crore and we have taken the help of a US company, Wildwell Control,” Reddy said. The money would be claimed from an insurance company, he added.

“The rig could blow up as the Blow Out Preventer (BOP) is being operated at pressure ranging around 7,000 pressure per square inch (PSI),” a deep-sea diver told this paper, speaking under condition of anonymity. “Usually the pressure on the BOP depends on the depth being drilled.” Sagar Shakti was drilling the seabed for oil pockets in the location since May 97. The floating rigs Sagar Vijay and Sagar Bhushan were previously carrying out oil exploration jobs since February 1996.

ONGC has already incurred heavy costs over the hole. Sources said that about 10 million dollars had already been spent on drilling the hole and an additional few millions more could be incurred to kill the well mouth. A standby vessel could cost around Rs 14 lakh per day and foreign experts are being paid around US $ 3,000 on daily basis, sources said.

ONGC officials said vessel Sagar Bhusan began drilling at B-24-2 well sometime in April this year to reach a target depth of 3,167 metres, but even as the well was being prepared for production testing the accident took place about 81 metres under the surface. Shear rams were applied and the well was shut down, officials added. “At that time, the control operations could not be manoeuvred because of high pressure in the well,” said ONGC officials, “There were no injuries and no casualties were reported. The crew were evacuated and reduced to bare minimum,” the sources added.