OGJ Senior Staff Writer
HOUSTON, Mar. 24 -- Norway’s Petroleum Safety Authority has asked Statoil to respond to the agency’s questions regarding a gas leak from the Gullfaks B platform on Dec. 4, 2010, and PSA said its investigation identified serious deficiencies related to Statoil’s planning, approval, and execution.
Based on the Gullfaks B gas leak and earlier incidents on Statoil-operated installations, PSA asked Statoil to assess what measures it might consider necessary given the deficiencies that PSA identified. PSA gave Statoil until Apr. 29 to respond. Statoil made no immediate comment regarding the request.
The gas escape on Gullfaks B happened after maintenance work on a production well. PSA said workers reported that it proved impossible to operate emergency shutdown valves on the well.
No people were injured, but the leak created a serious situation, PSA said. “Personnel present in the area could have been subject to serious or fatal injury if the gas had ignited.”
As part of its internal investigation into the Gullfaks B platform gas leak, Statoil estimated 730 kg of gas leaked in 1 hr.
“A significantly higher leak rate than the one which actually occurred could very probably have caused the buildup of a large explosive gas cloud in the area and thereby represented an explosion risk with a substantial potential for becoming a major accident,” PSA said Mar. 24.
PSA’s investigation concluded deficiencies existed in how Statoil’s management supervised the maintenance of choke valves on Gullfaks B.
PSA said the deficiencies identified have features in common with shortcomings found during earlier Statoil incidents. These incidents include a gas leak on Snorre A in November 2004, the hydrocarbon escape in a Statfjord A shaft in May 2008, loss of well control on Gullfaks C in May 2010, and numerous incidents related to mechanical handling in the drilling area.
Contact Paula Dittrick at email@example.com.
Norway's safety officials seek explanation from Statoil