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Following up on the pipeline rupture PSIO asks BP for more comprehensive reporting on its actions resulting from the Prudhoe Bay artificial lift gas pipeline break Alan Bailey Petroleum News
On Sept. 29 a high-pressure artificial-lift gas pipeline on Y-Pad in the BP-operated Prudhoe Bay oil field on Alaska’s North Slope blew apart, sending a piece of steel pipe flying through the air.
Subsequent investigations both by BP, and by state and federal regulators, quickly determined that external corrosion of the pipeline had caused the rupture of the line. And in the wake of the incident, BP has undertaken a series of follow-up actions.
Alaska’s Petroleum Systems Integrity Office, the state’s watchdog organization for overseeing oilfield facility maintenance, has been monitoring the progress of the incident investigation. And on Feb. 20 PSIO issued an investigation status report in the form of a letter from PSIO Coordinator Allison Iverson to BP.
“All parties agree this was a very serious incident — had the high pressure gas pipeline failure occurred under slightly different circumstances, the results would have been catastrophic, potentially with loss of life,” Iverson said. “Ultimately the root cause of this incident was corrosion under (pipeline) insulation.”
Insulation removed Iverson said that in 1998 BP had removed a portion of the insulation from the pipeline to evaluate pipeline anchor welds. But the company did not re-install the removed insulation nor seal the remaining insulation, to protect the pipeline from moisture.
“These practices were in accordance with BPXA’s approved practices for pipelines at that time,” Iverson said.
Then, when BP examined the pipeline for corrosion again in 2003, the company did not inspect the section of pipeline that subsequently failed, because snow drifts had covered that pipeline section at the time of inspection. There was no follow-up on the missed inspection.
Iverson said that, through meetings between PSIO officials and BP following the pipeline rupture, BP had shown to PSIO multiple areas of improvement in its management of its Alaska operations.
“The PSIO applauds BPXA for its efforts to date,” Iverson said.
However, Iverson also said that PSIO is “deeply concerned with the timeliness and depth of the incident investigation,” saying that BP had not published its incident review summary until Jan. 13 and that the company had also stated that the investigation report was still being finalized.
Lengthy investigation
According to Iverson’s letter, BP told PSIO in November that the company’s investigation was taking a long time because the investigation team was looking into the question of whether, prior to the incident, company employees had expressed concern about exposed gas pipelines.
“Regardless of the reasons for the lengthy investigation, the PSIO sees a need for timely completion of BPXA’s root cause analyses,” Iverson said. “Indeed, the PSIO has reviewed similar incident reports from other Alaskan operators and found a much shorter response time (two weeks for the preliminary reports delivered to the state).”
Iverson also said that although the incident review that BP provided to PSIO correctly identified the cause of the incident — “moisture wicking under the insulation, causing external corrosion and ultimately rupture of the pipeline” — the review did not discuss contributory factors such as the lack of procedures either for re-insulating pipelines or for flagging the follow-up on missed inspections.
The corrective actions that BP listed in its incident review do not have assigned dates and there is no indication that accountability for the actions has been assigned to a level of management with appropriate authority, Iverson said.
“Due to the serious nature of the incident, the PSIO requests that BPXA completes all of the corrective action items by May 15, 2009,” Iverson said.
Regularly informed BP spokesman Steve Rinehart told Petroleum News March 2 that after the Y-Pad incident BP had moved ahead with its investigation “with deliberate speed” and had regularly kept PSIO informed of the company’s findings and subsequent actions.
“We shared preliminary findings with PSIO and others in October and November of last year,” Rinehart said.
And although the root cause of the incident was external corrosion of the pipeline, BP had determined that a contributing cause was the lack of a mechanism for tracking missed inspections, Rinehart said. Since the incident, BP has put in place a procedure to deal with the missed inspection problem, he said.
In fact, BP had already been in the process of upgrading its maintenance procedures at the time of the September incident, Rinehart said.
And within days of the pipeline rupture BP ensured that appropriate inspections had been carried out at 76 other sites on 26 high-pressure gas lines, he said.
BP is also in the process of developing new engineering standards for the sealing and re-insulating of pipelines, Rinehart said. Corrective actions Rinehart said that in its investigation report BP has clearly identified a set of recommended actions and that corrective actions resulting from the September incident have been assigned to senior management. Specific timeframes have been specified for carrying out the actions.
“Top managers are accountable to make sure this is done,” Rinehart said.
Iverson confirmed to Petroleum News March 2 that following the September incident there had been communication between BP and PSIO regarding the status of the incident investigation and follow-up actions. The purpose of PSIO’s Feb. 20 status report was to formally let BP know PSIO’s remaining questions regarding the incident, with a view to achieving closure to the incident investigation, Iverson said.
“We didn’t want it to be a never ending process for all involved,” Iverson said.
Iverson said that PSIO officials had met with BP to discuss the PSIO status report and that at that meeting BP had reviewed in detail the actions it was taking. BP showed PSIO its internal incident report and explained what it is doing, Iverson said.
Iverson said that PSIO is in frequent contact with BP and will be following up on the company’s actions by May 15.
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