Bu Hasa Incident, 7 May 2011
ADNOC Group Companies Briefing
Wednesday 20 July, 2011
Incident Description
• BuHasa Central Degassing Station (CDS) had an Emergency Shut Down (ESD). It resulted in oil leaks from the flow lines of Bu407 & Bu 570resulted in oil leaks from the flow lines of Bu407 & Bu 570.
• The central station was normalized at midnight and operation teams started to open the closed wells. At 0125 Hrs, one of the crews observed a fire at Bu407 flow li ( i t l 200 t f th ll h d) d th llline (approximately 200 meters away from the well head) and the well was isolated from the Wellhead.
• Another Operations team (driver and four crew members) proceeded to Remote Degassing Station (RDS‐3)to isolate the well from the station. Close to RDS‐3there was a separate oil leak from the flowline of Bu570 covering the main access track (approximately 300 meters from the RDS‐3).
• While crossing the oil pool, the vehicle caught fire. It resulted in five causalities (four fatalities, and one crew member sustained minor injuries)
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Key Findings
1) The integrity of flow lines is not assured. (Under "upset" conditions ‐ when CDS is shutdown – pressure in the flow lines exceeds normal operating pressures and the chance of leaks is increased).
2) Bu Hasa CDS plant was shut‐in due to an ESD Level 1.2) Bu Hasa CDS plant was shut in due to an ESD Level 1.
• Trip initiated by a problem at the communication link between DCS and Emergency Shutdown System (ESD) with fuse failure in the ESD.
• Time to identify fault was around 6 hours. Time required to resolve problem was too long for such a y q p gfailure; especially for such a critical asset
3) Current design does not have over‐pressure protection at the existing wells.
• The HP pilot is an operational mechanism to close SSV and avoid holding the flow line under high pressure. Note flow lines are designed for CITHP Majority of wells did not trip on HP following the prolonged shut down and build up of pressure.
4) Wellhead maintenance is not always executed as per schedule.
5) Operations at night in response to emergency / incident was not identified as a “critical activity". Risk assessment and scenario analysis had not been undertaken.
6) HAZOP/ SIL revalidation for Bu Hasa facilities has not been undertaken within last 5 years.
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7) Laborers are not issued with fire resistant coveralls.
8) Logistics management during emergency was not adequate or recorded
Cause Tree Analysis
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Root Causes
1) Inadequate Risk Assessment
2) Inadequate identification of job hazards (Night time journey for operation requirements not risk assessed)
3) Inadequate Enforcement of Critical Behaviors (Maintenance)3) Inadequate Enforcement of Critical Behaviors (Maintenance)
4) Inadequate work planning (Maintenance schedule for critical equipment were not met)
5) Inadequate Design for Pigging Chemical injection (for flow lines) (Flow (2) line design does not allow pigging/chemical injection)
6) Inadequate technical Review of Engineering design (ESD Design Redundancy)
7) Inadequate Assessment of Required skills I Competency ( Lack of competent staff to ensure maintenance of SSV)
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Main Findings : Flowline Integrity
Finding
The integrity of flowlines is not assured. There remains a concern over internal and external corrosion. In a 2008 Flowline Integrity report, 61% of flowline leaks were attributed to external corrosion.
Under “upset” conditions when CDS is shutdown pressure in the flowlines exceeds normal operating pressure and theUnder “upset” conditions – when CDS is shutdown – pressure in the flowlines exceeds normal operating pressure and the chance of leaks increased.
Causes
•Specification for flowline is uncoated carbon steel pipe. Carbon steel is prone to internal & external corrosion.• Flowlines are difficult and often impossible to inspect for external corrosion i.e. buried under sand.
• Flowlines are not inspected routinely for internal corrosion. – IPS trials undertaken on 4” & 6” lines in 2004/5. Cost was high (especially as no launchers / receivers)
– Alternative methods to inspect for internal corrosion (e.g. strap on US devices) have been tested but not routinely used.
• Flowline replacement program is directionally good but the evaluation criteria for replacement are indicative (age, water cut etc) and criteria established with economic impact in mind. Only a few flowlines are identified for replacement each yearwhilst the actual exposure is higher.
• ADCO has acknowledged this flowline integrity problem and undertaken various studies and trials. However, ADCO focused on environmental risk and underestimated the safety risks. ADCO has worked to reduce the number of flowline leaks over the years with its flowline replacement program and has been effective in minimizing environmental impact with thorough clean‐up. With this and did not resolve the issue with urgency.
HSEMS Element # 5.2 Asset Integrity
5 2 4 M i t i i i t it f i ti f iliti
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o 5.2.4 Maintaining integrity of existing facilities
o 4.2.1 Improper risk evaluation & assessment
ADCO OIL SPILLSADCO OIL SPILLSYTD A il 2011YTD A il 2011
50 100Number of Oil Spills % Recovery
YTD April 2011YTD April 2011
42
34
40 80
19
29
25 26
20
30
40
6026
1419 18
10
20
20
40
712
1
6
02003 2004 2005 2006 2007 2008 2009 2010 Apr 2011
0
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No. of Onshore Spills > 6 Bbls No. of Onshore Spills < 6 BblsTotal No. of Oil Spills Total % Recovery
Main Finding : Flowline Integrity (cont’d)Prior and Ongoing Work
• 2008 publication of “Oil Pipeline Integrity assessment & Management Report”, Bu Hasa.
Recommends hydrotesting @ 125% MAWP to ensure integrity for > 5 yrs; mothballing for > 3 days no flow; Inspection using guided wave US or bell hole. [2005 – IPS trials 4” & 6” flowlines]g g
•1st Flowline taskforce in 2008 delivered “Standard for Integrity of New flowlines” in 2009.Tested magnetic tomography on 5 lines in Asab. Trial partially successful.
•October 2010 – Guided wave ultrasonic inspection of flowlines successfully trialed in Bu Hasa • 2nd Flowline taskforce was established by ADCO CEO in 2010 to focus on existing flowlines.2nd Flowline taskforce was established by ADCO CEO in 2010 to focus on existing flowlines.
– Workshop conducted with ADNOC group, consultants & contractors. Result : HDPE liners. Trial approved by CEO for 2 companies on 28th April 2011.
– Extensive data gathering to analyze trends & identify critical lines.
– March 2011 – taskforce refocused as ‘Flowline Leaks Management”. TOR covers:March 2011 taskforce refocused as Flowline Leaks Management . TOR covers:
• Short Term (2011) : HDPE liner trials, flowlines pigging/dewatering strategy, mothballing, prioritized intervention
• Long Term (2012‐3) : Martial selection strategy (GRE/RTP), Chemical treatment, coating, improvised supports
Recommendations
With urgency and dedicated resources finalize the revised flowline design specifications and integrity assurance practices sothat flowline leaks will be an “abnormal” occurrence i.e. move ASAP from study phase to implementation.
Priority to be afforded to those flowlines which have higher safety risk i e near RDS CDS track crossing near access tracks
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Priority to be afforded to those flowlines which have higher safety risk i.e. near RDS, CDS, track crossing, near access tracks.
(It is recognized that a “turn around” program on flowline integrity will take time to enact. Operational controls will need to be put in place to manage the risks of flowline leaks in the interim.
Main Finding : Flowline Integrity (cont’d)
Action Items
h f “ l l k ” h ld b f d f b d1. The TOR of “Flowline Leaks” team should be refocused for DELIVERY ‐ team resources to be reviewed; program established with defined deliverables and timeline to reflect the urgency; progress reports provided to Sponsor.
2. Start implementation of proven integrity assurance activities in the fields ASAP i.e. considering hydrotesting, IPS of suitable flow lines, Guided wave US inspection.
3. Although the existing procedure requires flowline mothballing when flowlines are shut in for > 3 days, the current practice is > 3 months. Review procedure, amend if necessary and rigorously apply procedure (include in procedure how status of flowlines is to be monitored and assign responsibilities).p ( p g p )
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Main Finding : Field Operations at Night
FindingOperations and Field Services staff were mobilized to the field at night to either close wells (after plant trip) or open up
wells (to re‐establish production).• Operations at night in response to emergency / incident was not identified as a “critical activity”. Risk assessment
and scenario analysis had not been undertaken.• Although the ‘unwritten guide’ was to attend to wells that were directly accessible from main tracks, field staff
traveled cross‐country.
Causes• Under pressure to manage wells and restore production, field staff were mobilized at night.• Bu Hasa Field Standing Order 02/2007 (Amendment 2) of 30th December 2008, night trips are authorized to “Respond to any emergencies / accidents / incidents in the Bu Hasa area. 18:00 hrs to 06:30 hrs”. Duty Manager approval is not required for authorized trips. Type of route is defined as “black top and sand track”. Being an authorized journey – no special preparations (hazard identification, specific route instructions, specific work instructions) were required or taken.
HSEMS Element # 6.1 Implementationo 1.1.6 Visibility – Management evaluate HSE aspects before business decisions takeno 1.1.6 Visibility Management evaluate HSE aspects before business decisions takeno 6.1.1 Implementation of work instructions
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Main Finding : Field Operations at Night
Recommendations• Review field operating philosophy• Review field operating philosophy.
oConsider manned RDS’s (vs adhoc night operations) & automation.• Night Operation should necessitate specific preparation with explicit authorization at appropriate level.• A guide is required to assist duty managers to make the appropriate decision when considering restoration of production after a plant trip versus field operation at nightrestoration of production after a plant trip versus field operation at night.
Action Items• Review operating philosophy wrt manning of RDS, automation etc. Prepare analysis and make proposal.p g p p y g , p y p p1. Amend field procedures & instructions such that night operation is considered as an abnormal and higher risk activity ‐ to be undertaken after consideration of inherent risk versus objective at appropriate leadership level, under specific controls and defined procedure.• Quick win : Fit vehicles which could be mobilized at night with search/flood lights. (Already actioned in Bu g / g ( yHasa.)
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Finding : ESD trip and Response
Finding•Bu Hasa CDS plant was shut‐in due to an ESD Level 1.
• Trip initiated by a problem at the communication link between DCS and Emergency Shutdown p y p g ySystem (ESD) with fuse failure in the ESD.
•Time to identify fault was around 6 hours.• Time required to resolve problem was too long for such a failure; especially for such a critical asset.
Causes•The ESD system has dual power supplies i.e. redundancy provided in design. However, the other power supply card for this particular ESD system sector had been faulty for some time. Redundancy and therefore system reliability was thereby defeatedsystem reliability was thereby defeated.
•Power supply card failure is a reoccurring event i.e. > 15 failures.•Maintenance staff called to investigate DCS/ESD problem did not have sufficient familiarity with the systems to investigate and identify the problem quickly. There was a reliance on off‐site vendor support.
•HSEMS Element # 5.2 Asset Integrity & 3.4 Competencyo 5.2.4 Reliability of protective systemso 3.4 Competence assurance
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Finding : ESD trip and Response
Recommendations• Maintenance of safe guarding systems is essential. Spare parts must be stocked. Reoccurring problems h ld b l d b d d f d d b d bshould be resolved by Vendor. Any deviations from standard maintenance practice are to be approved by a designated authority (M.O.C.). In the case of Critical Safety Systems, it is proposed that authority to deviate from the standard practice is carried at Management level.•Improve on‐site support for control and safe guarding systems
d ( d d d l l•Review competence and training requirements. (Recommend training engineers to an advanced level of systems troubleshooting) Review the current practices in sister OPCO’s.
•Provide 24/7 coverage with trained systems engineers.
Action Items1. Ensure that Critical Safety Systems (especially ESD, F&G) are properly maintained. Resolve the
reoccurring power supply failures with Vendor. In the mean time, ensure adequate spare parts are available to account for frequent power supply card failuresavailable to account for frequent power supply card failures.
2. Establish positions and define competency requirements for System Engineers.
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Finding : SSV reliability & functioning
Finding•The majority of wells did not trip on HP following the prolonged shut down and build up of pressure.•Note : Flowlines are designed for CITHP•Note : Flowlines are designed for CITHP.
CausesHP pilots are found to be frequently out of calibration or not functioning‐ HP pilots are found to be frequently out of calibration or not functioning.
-Set points of HP pilots are not systematically reviewed to account for the deterioration of flowlines due to corrosion. (Note : There is a difficulty to identify problematic flowlines and also to estimate the appropriate reduction in HP pilot set point.)
HSEMS Element # 6.3 Performance monitoring & Records
Recommendations•Review design philosophies and over pressure protection from the well head through RDSs all the way to the CDS in view of changing reservoir conditions, flowline aging and recent enhanced design practice.
•Implement a work practice to periodically review the suitability of ‘wellhead to CDS’ facilities specification and instrumentation set points. Under MOC procedure, accommodate any change in operating/design conditions and to be consistent with latest inspection/integrity records.
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Finding : SSV reliability & functioning
Action Items
1. Review Facilities Design from wellhead to CDS
2. Review the high pressure set point of pilots. The current set point of 1000 psig may be too high for either operational requirement or flowline condition.
3. SSV and associated pilots should be functionally tested, test results documented and signed off and results loaded in MAXIMO as per API RP 14 C.
4. Evaluate alternative pressure sensors with higher reliability for HP / LP pilots at wellhead (noting the harsh desert environment)harsh desert environment).
5. Review the SIL classification of the over‐pressure protection i.e. refer to new configuration with dual pilots and valves, as installed in selected service in other fields
6. Evaluate surge pressures which may be transferred through system to wellheads when CDS ESD l lvalves close.
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Finding : Wellhead Maintenance
FindingWellhead maintenance is not always executed as per schedule.
Causes• Inadequate planning and assurance• Inadequate manpower resources• Many MAXIMO records for wellhead maintenance are inadequate to provide a reliable history record.• HSEMS Element # 5.2 Asset Integrity & 3.2 Resources
o 5.2.4 Maintaining integrity of existing facilitieso 3.2.2 Resources
Recommendations• Resolve manpower resource requirement.• Analyze why staff are not loading data into MAXIMO and correct. (Training? Time? Supervision/)• Improve write‐up of maintenance procedures for wellhead equipment (e.g. Standard Procedure 7070)• Institute an assurance maintenance management system including self‐audit verification process• Train staff on data analysis in MAXIMO. • Review functionality of MAXIMO for ease of use.
ActionsStarting with Bu Hasa field but eventually addressing all fields undertake a comprehensive review of
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Starting with Bu Hasa field but eventually addressing all fields, undertake a comprehensive review of maintenance practices. Review to include fit for purpose procedures, manpower resource availability and competence, control and assurance processes, use of MAXIMO.
Finding : Emergency Response & Incident Management
Finding• HSE Team was not aware of the shutdown as ESD level 1 was not considered as an emergency• HSE Team was not aware of the shutdown as ESD level 1 was not considered as an emergency.• Inadequate communication means (mobile phones used; not radios).• Safety & loss prevention team was dispatched to attend fire at Bu 407; used GMC pick‐up. Unsuccessful attempt to fight fire of Bu‐407 flowline using powder fire extinguishers, carried in GMC pick‐up.
• Later a second safety & loss prevention team took RIV as search & rescue support to gatch road (Bu‐570• Later, a second safety & loss prevention team took RIV as search & rescue support to gatch road (Bu 570 flowline).
• Insufficient resources at RAMS (staff and ambulances) to manage a multi‐casualty accident(s). • Logistics management during emergency was not adequate or recorded.
Causes• Lack of clarity as to when a fire should be fought or not. Where other facilities or people are not at risk, it is advised not to fight an oil leak fire. The fire avoids gas cloud.
• The current Operating Philosophy is “burn down”. Implicitly and in relation to this specific event, fire fighting vehicles were not available for off‐road desert conditions.
• HSEMS Element # 5.6 Contingency Planningo 5.6.1 Contingency Planning
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Finding : Emergency Response & Incident Management
Recommendations• Review emergency response procedure to consider an ESD as an ‘emergency’ event.• Review fire fighting philosophy to consider intervention to avoid fire escalation e.g. fire in close proximity to flowlines / field facilities. Review fire fighting vehicle requirement (i.e. suitable for desert), water supply and equipment.
• Decision already taken to recruit professional fire fighting teams across ADCO assets. This will resolve l d h d h f f h b lleadership issues and shortcomings on fire fighting capabilities.
• Medical : Assess the needs for staff and equipment against realistic scenarios. (Medics vs population?)• Emergency Response : Further training necessary in emergency management process, risk assessment & procedures.
d f ld d f d d f d• Order field communication equipment as identified. Repair defective radios.
Actions• With the learnings from this Bu Hasa incident and with view to the proposed establishment of professional fire fighting teams in the Fields, review emergency / accident equipment requirements, p g g , g y / q p q ,support resources, implementation and training requirements.
• This is a major initiative which would have been undertaken as a matter of course with the introduction of the fire fighting teams. The scope of this initiative needs to be expanded to address associated emergency response system shortfalls.
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Finding : PPE Coveralls
Finding
•Not all coveralls issued by ADCO are fire resistant.• Laborers are not issued with fire resistant coveralls. (Laborer who escaped Bu Hasa vehicle fire thought hisLaborers are not issued with fire resistant coveralls. (Laborer who escaped Bu Hasa vehicle fire thought his coveralls were “plastic” and therefore flammable.)
Causes
• Lack of definition as to which staff must wear fire resistant coveralls.
•HSEMS Element # 5.3 Standards & Procedures
o 5.3.4 consistent application of suitable standards
d iRecommendations
• Review specifications for coveralls with respect to fire resistance for both ADCO and contractor staff.• If specification is not the same for all staff – provide definition of requirements for the various work groups.g p
Actions
•Advise end users (field and drilling staff and contractors) of the work situations / types for which fire resistant coveralls are mandated.
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Finding : HAZOP Revalidation
Finding
• HAZOP revalidation for Bu Hasa facilities has not been undertaken within last 5 years.SIL A t i d t i N b 2009• SIL Assessment was carried out in November 2009.
Causes
• HSEIA’s have been completed for all assets in 2009 and approved by ADNOC/SPC in 2010.
Th HSEIA d t i 5 l h d HAZOP lid ti h ll b d t d (Pl d t t• The HSEIA update is on a 5 year cycle where under HAZOP revalidation shall be conducted. (Planned start Bab in 2012)
•HSEMS Element # 4.1 Risk Identification, Evaluation & Assessment
o4.1.3 Up‐to‐date register of risks
Recommendations
Review adequacy of current plan for revalidation of HAZOP.
Actions
• Present plan for revalidation of HAZOP to GMC HSE and Risk Committee for endorsement.
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IMMEDIATE ACTION
• Identify High Risk flowlines:
P i it t l t i d d t ko Proximity to people movement , i.e. roads, sand track
o Close to facilities
Congestiono Congestion
• Wellhead Protection Equipment/Flowline:
o Immediate campaign to functionally test all SSVs, SCSSVs, and wellheadmaintenance.
o Hydrotest of vulnerable flowlines and repair accordingly.
o Flowline approach to RDS, CDS: excavation, exposure, inspection, repair,pipeline crossing and coat accordingly
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pipeline crossing and coat accordingly.
OTHER ACTIONSOTHER ACTIONS
• Implement flow line integrity programme across ADCO fields.
o Firm up aging flow line replacement philosophyo Firm up aging flow line replacement philosophy.
o Review flow line specification to reflect changes in production stream e.g. watercut.
• Review night time journey management.
o Review field operating and manning philosophy (i.e. CDS, RDS 24/7 coverage).
• Implement a maintenance assurance management system including self‐auditverification process.
• Review competency and training requirements (e.g. 24/7 coverage of trainedSystems Engineers).
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• Conduct Hazop Campaign for existing facilities every 5 years.
thankthank
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Key Recommendations
1) With urgency and dedicated resources finalize the revised flow line design specifications and integrity assurance practices so that flow line leaks will be an"abnormal" occurrence Le. move ASAP from study phase to implementation.
2) Implement confirmed integrity assurance activities Le. hydro testing, mothballing, IPS of suitable flow lines.
3) Review field operating philosophy. Review manned RDS's (vs adhoc night operations) &consider automation
4) Overall DCS/ ESD system design needs to be revised to improve reliability.
• Improve on‐site support for control and safe guarding systems
• Review competence and training requirements. (Recommend training engineers to an advanced level of systems troubleshooting) Review the current practices in sister OPCOs.
• Provide 24/7 coverage with trained systems engineers.
5) Review Facilities Design from wellhead to CDS( consider involvement of SH's)5) Review Facilities Design from wellhead to CDS( consider involvement of SH s)
• Review the high pressure set point of pilots. The current set point of 1000 psig may be too high.
• Consider carrying out functional tests of wells high pressure trip systems by shutting down downstream valve and observing the trip of the SSV as pressure builds up. This should be carried out at frequent intervals (say every six months) and would also act as a test of flowline integrity.
• Evaluate alternative pressure sensors with higher reliability,
• Consider over‐pressure protection means
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• Evaluate surge pressures (water‐hammer) which may be transferred through system to wellheads when CDS ESD valves close.
Key Recommendations (Cont’d)
6) Improve Maintenance
• Resolve manpower resource requirement.
• Analyze why staff are not loading data into MAXIMO and correct. (Training? Time?y y g ( g
• Supervisionj)
• Improve write‐up of maintenance procedures for wellhead equipment (e.g. Standard
• Procedure 7070)
• Institute an assurance maintenance management system including self‐audit
• verification process
• Train staff on data analysis in MAXIMO .
• Review functionality of MAXIMO for ease of use• Review functionality of MAXIMO for ease of use.
7) Review fire fighting philosophy to consider intervention to avoid fire escalation e.g. fire in close proximity to flowlines /field facilities. Review fire fighting vehicle requirement and equipment.
8) Medical: Assess the needs for staff and equipment against realistic scenarios. (Medics vs population?)
9) Emergency Response: Further training necessary in emergency management process, risk assessment &procedures.
10) Order field communication equipment as identified. Repair defective radios.
11) Review specifications for coveralls with respect to fire resistance for both ADCO and contractor staff.
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) p p
12) Review adequacy of current plan for revalidation of HAZOP/SIL revalidation. Present evaluation and recommendation to GMCHSE and Risk Committee for endorsement.