IMPROVING BLOWOUT RESILIENCE

Transcription

1 IMPROVING BLOWOUT RESILIENCE DrillSafe Perth, Thursday 6 th March 2014 Colin Stuart BEng. FIMechE

2 Blowout incidents prevalence & impact Dissecting a blowout Human & organisational factors Blowout resilience Contents

3 Uncontrolled flow to surface from aquifer

4 Unusual techniques to regain well control

5 Montara (2009)

6 Macondo (2010)

7 This is still happening

8 This is still happening.

9 This is still happening Gas Broach to surface, Barge Rig

10 Gas Leak through WH assembly: A clear view of gas leak coming out of 4 ports

11 Best estimate of the current number of Loss of Well Control incidents (requiring outside assistance) is approx.160 incidents per year (worldwide). Prevalence of Loss of Well Control incidents

12 From these blowouts we see a common trend of organisational failure with respect to well barriers. What could help Organisations become more Resilient to Blowouts? First we need to try to understand why and how organisational failure occurs, with respect to barrier integrity. Investigation - Influence of the organisation

13 INVESTIGATION Evolution of the Blowout Design Execution Barrier Integrity Processes & Rules Reporting What also emerged... Impact of the organisation Underlying causes Data interpretation re-engineering Documentation review -,000 s of pages Intensive analysis of barrier compliance 5 person team over several months Investigation Typical forensic exercise-400 page report

14 Installed Montara Well Head Platform Plug &Abandoned well for sidetrack operations Submitted approval for temporary suspension plans to regulator. Suspension with 2 x pressure containing corrosion cap was different from original programme Pressure tested 9 5/8 Casing & bled off Over displaced 16 bbl of seawater into casing leading to contaminated shoe track cement. Installed 9 5/8 PCCC. Did not install 13 3/8 PCCC Cont Drilling commenced Drilling of sidetrack commenced Set 9 5/8 Casing and bumped plug Casing float failure causing 7 bbls of cement to backflow into casing Wait On Cement and cement set Investigation Drilling to temporary suspension

15 13 3/8 PCCC not installed as recorded in DDR. 20 Trash Cap was installed. Re-entry commenced Ran MLS thread cleaning tool. The 9 5/8 PCCC was removed as it interfered with the thread cleaning tool. Drilling continued Temporary Suspension 5 Months Re-entry Cont Removed BOP Temporarily suspended sidetrack well and rig was released from Montara WHP Sidetrack had 3 unverified barriers, Removed 20 Trash Cap. Since 13 3/8 PCCC was not installed corrosion of the wellhead threads observed. Investigation - Temporary suspension & re-entry

16 Observed liquid flowing from well and later confirmed to be crude oil. All hot work ceased All personnel reported to muster station Decision made to skid rig back onto well to install a mechanical plug barrier General muster alarm sounded and crew cleared the rig Well Killed Continued Re-entry Well Capped Installed 20 conductor riser after thread cleaning operations Rig skidded over to other wells Decision made not to reinstall the 9 5/8 PCCC Gas alarm sounded Well flow subsided and personnel stood down Blowout occurred before skidding operation could commence. Relief well intercepted mother bore, fire on WHP, oil flow into ocean stopped Observed well to be full of liquid, believed to be the column of sea water Investigation Blowout and well kill

17 Investigation How did we assess the Well integrity condition on Montara? Used a backwards looking technique to see if situational awareness around barrier integrity monitoring existed.

18 Procedures deviating from corporate standards Frontline decision making by rules of thumb Barrier policy not adhered to Management of change system not enforced Inadequate documented Risk Assessments Insufficient regulator oversight Daily reports factually incorrect Insufficient focus on well integrity management Common blowout investigation findings

19 ORGANISATIONAL FACTORS Group thinking Silence of dissent Autocratic leadership Lack of organisational resilience Fast Track preparation No cross checking Shortcut culture Weak support during safety critical operations Expertise is concentrated either at the rig or in the support team, but not both Silo behaviours HUMAN FACTORS Confirmation bias Lack of situational awareness Acceptance of unexplained failure Weak standards adoption Rules of thumb Blowout Findings in terms of Human & Organisational Factors

20 If we can identify the Organisational and Human factor traits giving high exposure to blowouts, it is then reasonable to say that the opposite of these traits would represent a Blowout resilient organisation. Proposition

21 Rules-based decision making On-line support from the organisation Relentless focus on barrier integrity Collaborative technologies Re-focus on standards and implementation Improving Blowout Resilience

22 Thank You #21-01,101 Thomson Road Singapore