Hose bursts at Repsol well

A North Slope exploration well operated by Repsol E&P USA Inc. released some 3,780 gallons of oil and other fluids after a hose ruptured during recent flow back operations.

As Repsol contractor Weatherford International was conducting a flow back test on the Qugruk No. 6 well on April 9, a hose connecting the well to a storage tank ruptured, spraying a mixture of 60 percent water based frac fluids, 35 percent diesel and 5 percent crude oil onto the tundra, according to the Alaska Department of Environmental Conservation. The operator shut-in the well, but additional products spilled into a secondary containment area as fluids from the tank drained back through the hose.

Repsol originally estimated the spill volume at 6,600 gallons, but reduced it after measuring the volumes recovered during the initial clean up of the containment area.

Work resumed

The majority of the spilled products stayed with a secondary containment area, but Repsol reported a “light to moderate mist” over some 0.63 acres of snow-covered tundra, according to DEC. There have been no reported impacts to wildlife, DEC said.

DEC said responders had cleaned 25 percent of the misted area as of April 9.

Repsol removed most of the spill products from the secondary containment area using on-site vacuum equipment and response crews continue to work around the clock to complete the job, according to DEC. Additionally, Repsol is preparing a plan for cleaning up the contaminated snow from vegetated areas of the surrounding tundra.

Qugruk No. 6 is a new well in the location where Repsol drilled the Qugruk No. 2 well in early 2012. The Qugruk No. 2 experienced a shallow gas kick at around 2,500 feet en route to a deeper oil target, sending thousands of gallons of drilling mud onto the tundra.

As of late March, Repsol had already completed a 7,809-foot vertical section of the Qugruk No. 6 well and planned to drill a horizontal lateral before completing the well.

—Eric Lidji