Thursday, March 1, 2012

Repsol still works to thaw frozen drill rig at blowout site

Tim Bradner
Alaska Journal of Commerce

Repsol E&P USA was still working last week to thaw and clean a frozen drill rig at the site of its Qugruk No. 2 exploration well on Alaska’s North Slope, state officials said. The rig was evacuated the morning of Feb. 15, when drillers encountered a shallow gas pocket at the 2,523-foot depth, causing a gas blowout and spill of drilling fluids.

There were no injuries or fire resulting from the blowout. Gas stopped flowing the evening of Feb. 16.

The well cannot be considered under control until the rig is brought back into operation, said Cathy Foerster, a Commissioner on the Alaska Oil and Gas Conservation Commission.

“It’s going to be later this week, at least, until they can start work to reestablish mud circulation in the well. If they are able to do that the well will be under control and they can proceed to inspections of the drill pipe and the condition of the hole,” Foerster said Feb. 24.

The AOGCC is the state agency responsible for drilling safety. Nabors Alaska Drilling Co. is the owner and operator of the rig.

In a situation report issued Feb. 27, the state Department of Environmental Conservation said technicians at the site were to inspect the “cold start generator” on Feb. 27.

“The cold start generator will be the first generator to be started and supplies the power needed for the restart of the rig,” the DEC said in the situation report. “The restart of the rig is one of a series of steps in the progression needed for completion of the well-kill operation. However, due to the need for a very methodical and careful cleaning and drying of the rig’s power components, the time of the restart cannot be determined at this time.”

Foerster said the drillers will check to see if the well and pipe can be salvaged or if a new well will have to be started. If drilling resumes, officials will inspect for possible gravel wash-out around the wellbore and the possible formation of an ice or debris plug.

“If there is a debris or ice plug, they will have to be very cautious because there might be gas below it,” she said.

Meanwhile, Repsol reported to DEC that its contractors have removed 1,260 barrels of liquids, mostly snow contaminated with drilling fluid, from the site, the agency said in the Feb. 27 report. The drill fluid was water-based rather than diesel-based, which will lessen its environmental impact. The drill fluids were ejected from the well by the gas when the well blew out.

Qugruk No. 2 is approximately 150 miles southwest of Barrow, on state-owned lands in the Colville River delta. The nearest community is the Inupiaq Eskimo village of Nuiqsuit 18 miles south of the well location.

The well is one of five exploration wells Repsol is hoping to drill this winter to assess acreage acquired last year in a deal with Armstrong Oil and Gas Co., a Denver-based independent. Several of the leases have near-term expiration dates, state Division of Oil and Gas director Bill Barron said, which is why Repsol has mounted an aggressive exploration program this winter.

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