The operation to ‘kill’ the blowout gas well at Baghjan in eastern Assam’s Tinsukia district was suspended on Tuesday after a valve in the well casing pipe gave way.
Experts engaged by exploration major Oil India Limited (OIL) had begun killing Well No. 5 after capping it by placing a blowout preventer on Monday. Two earlier attempts to place the preventer, vital for stopping the outflow of gas, had failed.
Killing is a technical term for injecting a viscous mud-cement mixture at high pressure through an inlet in the blowout preventer at very high pressure to stop the pores at a depth of 3.5 km underground from where the natural gas and associated condensates have been spewing since the blowout on May 27.
Injecting the killing fluid can be done at a stretch for up to 10 hours.
“The killing operation was unsuccessful due to the blowing out of a valve on the well casing pipe. Mud pumping was stopped and now the gas is escaping through the blowout preventer riser as earlier,” an OIL spokesperson said, adding that the foreign experts would suggest the next course of action.
Officials said capping a blowout-affected well was a major success 83 days after the disaster took place.
“Killing the well will help us stop the uncontrolled outflow of gas as well as the fire,” the spokesperson said.
The well had burst into flames on June 9. The disaster affected more than 1,500 families living in the vicinity besides endangering wetlands and the Dibru-Saikhowa National Park close by, government and private agencies engaged in studying the impact said in their reports.
OIL had flown in three disaster control experts from Singapore before the Baghjan well caught fire.