After weeks of trying to salvage the well while bringing it under control, Repsol E&P USA now plans to plug and abandon a North Slope oil well that blew out in February.
The Spanish major is working with the Alaska Oil and Gas Conservation Commission to finalize its well control plan for the Qugruk No. 2 well before beginning operations.
The response crews used a coiled tubing unit to clear an obstruction from inside the drill pipe, but a subsequent wireline diagnostic well logging showed the presence of two “bridges,” or obstructions in the annulus, the space between the pipe and the rocks, according to a March 13 situation report from the Alaska Department of Environmental Conservation. The crews attempted to move the pipe in order to clear the obstruction and allow fluids to circulate between the inside of the drill pipe and the annulus, but failed.
The crews continue to steam thaw frozen drilling mud around the well site. Through March 13, crews had shipped 87,906 gallons of thawed mud and water, and 2,299 cubic yards of frozen drilling mud from the well site for disposal, according to the DEC report. The cleanup effort cannot begin in earnest, though, until the well is under control.
The Qugruk No. 2 well blew out on Feb. 15, when the exploration well hit a shallow pocket of natural gas at about 2,500 feet en route to a deeper oil target at around 7,000 feet. The well is located on the Colville River delta some 20 miles northeast of Nuiqsut.
The blowout sent some 42,000 gallons of freshwater based drilling mud onto the ice pad and the surrounding snow-covered tundra, and vented an unknown amount of gas, but did not lead to any injuries or explosions and did not cause any oil to be spilled on the tundra.
Following the incident, Repsol suspended its North Slope drilling program and the AOGCC withdrew all the Qugruk drilling permits and asked Repsol to reapply for them.
—Eric Lidji
