The Macondo Incident JEB

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    Worldwide DrillingNorthern Bus iness Uni t ,

    Conventional Gas Exploi t at ion

    The Macondo Inciden

    Findings and Conclusions Prior to

    Published Inspection of the Subsea BOP

    12 October, 2010

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    CONFIDENTIAL

    FOR MARATHON OIL COMPANY USE

    ONLY

    The material contained in this

    presentation is for internal trainingpurposes and is not to be further

    distributed

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    The Event

    On the evening of April 20, 2010, control

    of the BP operated Macondo Well, located

    in approximately 5,000 of water inMississippi Canyon Block 252, was lost.

    This loss of well control resulted in

    explosions and fire on board

    Transoceans rig Deepwater Horizon.

    Eleven people lost their lives and 17

    others were injured.

    The blowout fed the fire for another 36

    hours until the rig sank. Hydrocarbons

    continued to flow uncontrolled from the

    wellbore for 87 days, resulting in a spillof national significance.

    A response effort of unprecedented size,

    technical complexity, political pressure,

    media coverage and cost continues

    today.

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    The First 36 Hours

    At the time of theincident we had two rigs

    operating in the GOM, the

    Noble Paul Romano at

    Innsbruck (MC 993) and

    the Diamond Ocean

    Monarch at Flying

    Dutchman (GC 511).

    Our supply vessels

    were directed to the scene

    for SAR operations and

    fire fighting.

    The Ocean Monarch

    was contacted for use of

    their BOP ROV

    intervention stab, but the

    Ocean Endeavor had the

    same model and was

    closer.

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    An Unprecedented Response Effort

    As an Industry we watched as

    hours turned into days, days

    became weeks, and weeks

    grew into months. In contrast

    to the failures which led to the

    blowout, the response effort

    was nothing short of

    phenomenal.

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    The Flow Path

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    The Flow PathIn the early days of the incident we, along with most of the industry, identified the three potential

    flow paths for the blowout: Annular flow thru a failed or off-seated casing hanger pack-off,

    annular flow thru parted or leaking production casing, or flow thru the float equipment.

    The majority of the industry, including us in the early days, became convinced that the flow pathwas thru the casing hanger pack-off. We reached this conclusion for two major reasons:

    1. Reports confirmed that the lock-down sleeve had not been installed before the blow-out

    occurred. Quick calculations indicated that if hydrocarbons had been allowed to migrate

    during and after the cement job, forces due to probable differential pressures could have off-

    seated the hanger and pack-off.

    2. More importantly, the feeling was that whatever happened occurred so fast that the rig crew

    had no time to react appropriately. The thought of an influx coming all the way from TD to

    surface without being detected and secured was considered next to impossible and

    dismissed.

    As days turned into weeks, several of us began to question why the exposed formations had not

    failed, collapsed and bridged over the flow path. There are several hundred feet of open

    formation between the productive interval and the 9-7/8 liner shoe. Despite the implications(well unloaded from the bottom, up the production casing, undetected), some of us reached

    the conclusion that flow through the float equipment was the only path that could explain the

    sustained flow without bridging.

    Unfortunately BPs investigation team, which had access to much more information than the

    majority of the industry, reached the same conclusion based on multiple pieces of evidence. They

    go so far as to state that well control efforts were not initiated until 49 minutes had elapsed and

    approximately 1,000 bbls of influx had occurred.

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    Evidence of Flow Path from BPs

    Accident Investigation

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    Well Design Information

    The discussion regarding the flow path is important because BP was heavily criticized

    for running the final production casing as a long string. The assumption was that

    annular flow thru poor cement and a damaged or off-seated casing hanger pack-off

    was the failure mode.

    The investigation team included a diagram that suggested the original Macondo well

    plan called for a long string of production casing (9-7/8). According to mutual

    partners, this design is not uncommon for BP. While it eliminates at least one annular

    barrier (liner-top packer), it also eliminates leak paths associated with liner hangersand tie-back seals. In some cases this design provides mitigation for annular pressure

    build-up, and this appears to play heavily in BPs decision to install long strings.

    Although we have not utilized a long string in our deepwater completions for a variety

    of reasons, it is not appropriate to say the use of a long string across a productive

    interval is negligent. Multiple risks and hazards must be addressed on a case-by-case

    basis, and there may be times that a long string provides the best solution.

    It is the design, installation and proper verification of barriers that is critical

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    Original Well Design and Actual

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    Findings From BPs Investigation Team

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    Investigation Teams Representation of

    the Physical or Operational Barriers

    Breached

    Disasters of this nature and magnitude are almost always the result of multiple failures. These

    failures often involve decisions made, actions taken (or not taken), and barriers. The Macondo

    Incident is no exception.

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    Well Integrity Was Not Established or

    Failed

    The cement did not isolate the

    hydrocarbons from within the

    annular space behind the

    production casing

    The shoe track (cement and float

    equipment) failed to provide an

    effective barrier

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    Cementing Operation

    The Investigation Team determined the annular cement failed

    to isolate the hydrocarbon bearing zones for one or more of

    the following reasons:

    Foamed slurry was likely unstable and allowed nitrogen to

    break out

    No fluid loss additives were included in the slurry

    Complete lab testing of the slurry was not performed

    Contamination of the slurry due to the small volumepumped

    Channeling due to insufficient mud removal was briefly

    discussed, with a base oil spacer and only 6 centralizers

    mentioned. The main focus, however, was on foam instability

    and possible contamination

    This complex slurry and spacer program was apparently

    designed to minimize ECD and maximize the chance of having

    returns. Having returns at surface during a cement job on a

    long string at this depth should very seldom be a primary

    objective, and actions taken to achieve this performance

    indicator can jeopardize the critical requirements for

    complete mud removal and minimal contamination of the

    slurry.

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    Cementing Operation

    The Investigation Report fails to state the slurry volume, the pump

    rate used to place it, and the results of the lab testing that was

    completed. They do state that full returns were achieved during the

    placement of the slurry.

    In a draft report from May, BP states that a 60 bbl slurry was

    pumped. Based on the wellbore details provided in the final

    report, the volume required to reach their planned TOC would

    have been slightly more than 50 bbls assuming a gauge hole

    The slurry and spacer densities were very close to the mud

    density. There would have been very little to no benefit fromdensity differences when displacing the mud.

    Although not stated (or at least not found by me), the pump

    rate while placing the slurry was probably on the low end if

    fracture margins were tight yet full returns were acheived.

    Rate (annular velocity) plays a very critical role in effective

    mud removal, minimizing contamination and eliminatingchannels.

    Time to develop compressive strength was not stated in the

    report. A Transocean investigation stated Test on 4/12 of

    7casing slurry : 0 psi compressive strength after 24 hours .

    Attempts to perform a negative test commenced

    approximately 16-1/2 hours after bumping the plug.

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    Cementing OperationBased on the information presented, the cement slurry design and implementation had a very low

    probability of ever providing an effective barrier.

    Apparently in an effort to maintain an exposed shoe (9-7/8 liner, for future annular pressure buildup

    mitigation), the overall slurry volume was maintained very close to a calculated gauge hole capacity.

    Therefore, a 16.74 ppg cap, followed by a nitrified 14.5 ppg lead, chased with a 16.74 ppg tailwas

    crammed into an overall volume of 60 bbls, preceded by a 6.7 ppg base oil and 14.3 ppg spacerto

    displace 14.2 ppg mud, all pumped at a rate slow enough to allow full returns in an environment

    with little fracture gradient margin through a tapered string of casing at over 18,000 deep.

    While there are many factors that must be considered in the planning of a cement job, often times rateand volume can overcome many deficiencies. Rate can help reduce the effects of poor centralization,

    inability to move the pipe, and reduced density differentials to name a few. Increased volumes

    compensate for enlarged hole conditions and contamination that occurs during the placement and mud

    removal process.

    If cement is going to be relied upon as a barrier, then achieving this becomes the primary objective in the

    design and execution. Had a significantly larger volume of non-nitrified cement with proper fluid

    loss additives and LCM material been pumped at a rate that ensured mud displacement anddiversion (if losses were experienced below the highest HC bearing zone), it is quite possible this

    disaster would have been avoided. At these depths and objectives, our practice has and continues to be

    non-nitrified slurries with tightly controlled fluid loss with LCM additives (if warranted), well centralized

    casing whenever possible, and rates that ensure proper mud displacement (despite no returns at

    surface the majority of the time). Ironically, had BP followed our general practice, their concern

    about maintaining an exposed shoe at the 9-7/8 liner would have been addressed automatically

    no returns equals no cement above the next shoe.

    h h k d l

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    The Shoe Track Cement and Float

    Equipment Failed to Provide an Effective

    Barrier

    The investigation team identified the following possible failure

    modes that may have contributed to the shoe track cements

    inability to prevent hydrocarbon ingress:

    1. Contamination of the shoe track cement by nitrogen breakout

    from the nitrified foam cement.

    2. Contamination of the shoe track cement by the mud in thewellbore.

    3. Inadequate design of the shoe track cement(reference to the

    set time of the cement in relation to the attempted negative

    test?)

    4. Swapping of the shoe track cement with the mud in the rat

    hole (bottom of the hole).

    5. A combination of these factors.

    Three possible failure modes for the float collar were identified:

    1. Damage caused by the high load conditions required to

    establish circulation

    2. Failure of the float collar to convert due to insufficient flow

    rate (reference to a low cement placement rate?)

    3. Failure of the check valves to seal.

    h Sh k C d l

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    The Shoe Track Cement and Float

    Equipment Failed to Provide an Effective

    BarrierWe have experienced more than one failure of this type of float

    equipment. While it is run as a double valved installation, an

    effective seal cannot be taken for granted.

    Typically, there is enough displacement pressure (differential pressure

    due to a heavier column of cement in the annulus) following a cement

    job to immediately determine if the float valves (check valves in the

    adjacent schematic) are holding.

    Due to the spacers, nitrified slurry, and very probable channeling and

    contamination, the differential pressure following the cement job on

    the 9-7/8 by 7 production casing would have been very little to none.

    Like we have witnessed more than once in our operations, the check

    valves may never have been holding. The difference here is there was

    probably insufficient differential pressure to make this determination.

    The investigation team pointed out multiple potential failure modes

    for the cement inside the shoe track. Exposing the cement to a

    negative differential before it was capable of providing a seal is a

    possibility as well.

    A more conventional, higher volume cement job may have provided the

    differential necessary to determine the integrity of the check valves.

    H d b E d h W ll

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    Hydrocarbons Entered the Well

    Undetected and Well Control was Lost

    Negative pressure test was accepted despite obvious signs that well

    integrity did not exist

    Influx was not recognized until hydrocarbons were above the subsea BOP

    Well control response actions failed to regain control of the well

    P i i T

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    Positive Test

    The Positive Test (2,700 psi) of the production

    casing was successful.

    Although from the opposite direction as the

    pressure differential experienced after displacing

    the riser to seawater, the casing and casing hanger

    seal assembly tested.

    Since the wiper plug had landed during the cementjob, the positive test pressure was unlikely to be

    transmitted to the shoe track.

    The positive test commenced approximately 10-1/2

    hours after the plug was bumped.

    At this point a sigh of relief was probably breathed.

    A very difficult, significantly over-budget well had

    just been cased, cemented and tested.

    It was also at this point that a False Sense of

    Security probably set in.

    I l I d N i T

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    Incorrectly Interpreted Negative Test

    Attempts were being made to

    accomplish more than one

    objective with the negative testing

    operation.

    The spacer referenced in the

    Deepwater Horizon Investigation

    was more accurately described as

    unused Form-a-Set and Form-a-

    Squeeze LCM pills in theDeepwater Horizon Interim

    Incident Investigation dated May

    24th 2010 (cant be discharged

    directly from rig, but if it goes into

    the well, then the returns can be

    discharged, so this was pumped

    ahead of the seawater with the

    intention of dumping after it

    returned to surface)

    Introducing this additional

    operation into a very safety-

    critical test may have added to

    the difficulty personnel

    experienced interpreting theresults.

    I tl I t t d N ti T t

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    Incorrectly Interpreted Negative Test

    When conducted in thismanner, the subsea BOP

    element utilized (ram or

    annular preventer) must hold

    a pressure differential from the

    top, opposite from what it is

    designed to accomplish.

    Ironically, the only ram in the

    stack designed to hold a

    differential from above was

    the test ram, the one heavily

    criticized as a useless ram

    in early media reports.

    The amount of fluid thatreportedly leaked by the

    annular preventer during the

    attempted negative test did not

    help the interpretation of the

    results (16.0 ppg LCM pill

    likely entered into and gained

    height in the kill line).

    I tl I t t d N ti T t

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    Incorrectly Interpreted Negative Test At some point it was decided to

    switch from the drill pipe to the kill

    line for monitoring.

    The kill line reportedly stayed at 0 psifor 30 minutes, while the drill pipe

    reportedly built to 1,400 psi over a

    period of time.

    The drill pipe pressure was explained

    as a bladder effect and the kill line

    observations were considered

    accurate. The negative test was

    considered successful and

    displacement of the mud and 16.0 ppg

    spacer with seawater continued.

    If two lines are connected directly

    to the same compartment, similar

    pressure responses (variances mayexist due to fluid density

    differences) should be observed. If

    one reads 0 psi and one builds to

    1,400 psi,you STOP and determine

    why such a discrepancy exists. You

    dont blame it on some mythical

    bladder effect.

    I tl I t t d N ti T t

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    Incorrectly Interpreted Negative Test

    I fl t i d til

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    Influx was not recognized until

    hydrocarbons were above the subsea BOP

    I fl t i d til

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    Influx was not recognized until

    hydrocarbons were above the subsea BOP

    Unrecognized Flow Indications

    In this case the drill pipe had already

    been completely displaced with

    seawater. The expectation should be

    that at a given flow rate, the drill pipe

    pressure should decline as mud is

    displaced from the annulus, then

    remain constant once seawater

    reaches the surface.

    During this displacement, influx nearthe bottom of the well displaced mud

    above the bottom of the drill pipe,

    causing a pressure increase. This

    unexpected response, even with the

    pumps off, apparently was not

    recognized.

    1. Drill pipe pressure increased by

    100 psi when it should have been

    decreasing (~ 39 bbl gain from

    20:58 to 21:08

    2. Drill pipe pressure increased by

    246 psi with the pumps off, and

    flow does not immediately drop off

    when shutting down the pumps

    3. Drill pipe pressure increased by

    556 psi with the pumps off, ~ 300

    bbl gain by now.

    Influx was not recognized until

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    Influx was not recognized until

    hydrocarbons were above the subsea BOP

    Influx continues to displace mud

    above the end of the drill pipe,

    causing the drill pipe pressure to

    increase with the pumps off.

    As hydrocarbons pass the end of

    the drill pipe and the displaced

    mud and mud-seawater mixture

    enters the riser (less height for agiven volume), the drill pipe

    pressure starts to decline, rapidly.

    It wasnt until the last pressure

    increase with the pumps off that

    someone decided something was

    not right, but the action taken

    was to apparently bleed off the

    drill pipe pressure.

    At this point the well must have

    been flowing at a very

    substantial rate for over 10

    minutes with the pumps off

    Influx was not recognized until

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    Influx was not recognized until

    hydrocarbons were above the subsea BOP

    Influx was not recognized until

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    Influx was not recognized until

    hydrocarbons were above the subsea BOP

    Influx was not recognized until

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    Influx was not recognized until

    hydrocarbons were above the subsea BOPThere have been several discussions regarding the factors that may have contributed to the failure to recognize the influx

    until it was well above the subsea BOP. The most significant of these, in my opinion, are listed below. I list these, and

    discount the others on the next slide, because of the following belief:

    As long as the BOPs and Marine Riser are attached to the wellhead, a conduit directly to the rig exists. As long as a

    direct conduit to the to rig exists, constant monitoring to ensure well control is maintained is required. The Driller is

    ultimately responsible, regardless of the other operations going on, for ensuring well control is maintained at all

    times.

    1. False sense of security prevailed since the wellbore had been tested positively, and the negative test had been

    mistakenly accepted as successful.

    2. When preparing to perform an operation, often times the responses can be predicted and should be expected. If the

    expected responses are not observed, then the operation should be stopped and the reason for the discrepancy

    should be determined and remedied. The pressure responses shown on the previous slides certainly deviated from

    what should have been expected. The Driller either did not observe these responses, did not comprehend that these

    responses should not be expected, or both. Since action was not taken until the last significant pressure increase

    (with the pumps off , 556 psi), one might conclude that he did not observe. The action, however, (bleed off the drill

    pipe pressure) indicates he had no comprehension of what should be expected and what was actually happening.

    3. It was not uncommon for us to displace the riser with no accurate pit monitoring, but when those cases existed, no-

    flows were obtained at scheduled intervals and someone was assigned to monitor the flow and confirm no-flow

    when the pumps were shut down. This was obviously not done on the Macondo well. Flow was not recognized for

    at least 49 minutes and after 1,000 bbls of influx. New regulations will likely prohibit displacements like this in the

    future. From now on, displacements will be done with a closed BOP in multiple steps.

    Almost 20 years ago I stood on the rig floor of a semisubmersible with the Senior Offshore Supervisor I was working

    nights for. He had worked his way up through the contractor ranks on semisubmersibles, and then hired on with

    Marathon. He retired not long ago. Pointing at the Driller on the brake, he said Incase you dont know, that is themost important person on this rig. He can sink this thing faster than anyone else onboard

    Influx was not recognized until

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    Influx was not recognized until

    hydrocarbons were above the subsea BOP

    Several other contributing factors have been stated or discussed. Some of these are listed below, but

    while these often receive significant discussion, they are not critical and should have had no impact onensuring well control was maintained.

    VIPs were on board to congratulate the crews for an achieved safety performance milestone. It

    doesnt matter who is onboard, ensuring constant monitoring occurs and well control is

    maintained should not be negatively impacted by visitors.

    Multiple operations were going on simultaneously, so attention to critical tasks was divided. There

    are always simultaneous operations taking place on a facility of this magnitude. Well control,however, must always be someones top priority; and that someone better understand this very

    clearly.

    Transfers of mud to a supply vessel were taking place prior to the displacement, making it difficult to

    monitor volumes. It was stated in the investigation report that the mudloggers were not

    notified when transfers ceased and apparently did not monitor the pit volumes. While often

    used for this task, mudloggers are not the ones ultimately responsible for continuouslymonitoring the well during all operations.

    The mudloggers flow meter was bypassed and pit monitoring was not possible once returns were

    routed overboard. Same as above, and other means of verifying the well is stable should have

    been employed (frequent no-flow checks, having someone dedicated to monitoring the returns

    and verifying no-flow each time the pumps are shut down)

    Well Control Response Actions Failed to

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    Well Control Response Actions Failed to

    Regain Control of the Well

    Well control response actions were not taken

    until water and mud started overflowing ontothe rig floor. At this point over 1,000 bbls had

    entered the well undetected and hydrocarbons

    were above the subsea BOP.

    Mud was expelled through the rotary table

    up through the derrick towards the crown

    block before the diverter was closed

    Pressure responses indicate an annular

    preventer was closed, but did not seal

    immediately. Transoceans protocol was to

    close the annular, then close a VBR.

    Eventually the pressure responses indicated

    a seal was obtained. The annular was only

    rated to 5,000 psi, and modeling indicatedan 8,000 psi differential could be expected

    at that point. The investigation team

    concluded that it was very likely that a VBR

    produced the seal.

    Well Control Response Actions Failed to

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    Well Control Response Actions Failed to

    Regain Control of the Well

    Flow from the diverter was routed to the mud gas separator (MGS), not directly overboard.

    This action, regardless of whether someone intentionally lined it up this way or if it was lined

    up to the MGS as SOP, ultimately eliminated any further human intervention to secure the well

    and perform emergency disconnect actions.

    This routing of a major gas event to the MGS resulted in component failures and the rapid

    dispersion of gas across large areas of the rig. Failure of the fire and gas systems to prevent

    ignition was listed as another failed barrier, but this is a weak statement. An event of this

    magnitude would quickly go beyond electrically classified areas, and multiple sources of

    ignition, including sparks generated by failed components, would have existed.

    The subsequent explosion likely took out both MUX cables in the moon pool, thereby

    eliminating any further actions by the crew to shear the pipe or initiate an emergency

    disconnect sequence.

    Well Control Response Actions Failed to

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    Well Control Response Actions Failed to

    Regain Control of the Well

    Instantaneous gas rates reached an estimated 165 mmscfd with pressures in excess of 100 psi

    Gas would have likely vented from: Slip joint packer, 12 MGS vent, 6 MGS vacuum degasser vent, 6

    overboard relief line (burst disk), 10 mud line under the main deck

    Well Control Response Actions Failed to

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    Well Control Response Actions Failed to

    Regain Control of the Well

    Well Control Response Actions Failed to

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    Well Control Response Actions Failed to

    Regain Control of the Well

    Well Control Response Actions Failed to

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    Well Control Response Actions Failed to

    Regain Control of the Well

    It is likely the explosion took out both MUX

    cables, preventing communication to the

    subsea BOPs

    Manual activation of either the High-

    Pressure Blind Shear Rams or the EDS

    would have been prevented. Testimony

    indicated that the EDS was pushed and the

    panel reacted like it should, but it never left

    the panel

    At this point, only the AMF (Automatic

    Mode Function) and ROV intervention

    remained

    Well Control Response Actions Failed to

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    Well Control Response Actions Failed to

    Regain Control of the Well

    Although the pressure responses indicated

    the subsea BOP sealed eventually, flowcontinued after the initial explosion based

    on the intensity of the fire.

    This flow may have come from several

    sources, including:

    Rig drifting or traveling equipment

    movement moved pipe enough todamage the VBR and allow flow again

    Damage to the drill pipe allowed flow

    into riser or onto rig floor area

    Surface equipment failures (swivel

    packing, kelly hose)

    Pressure relief valves on mud pumps

    allowed flow into pit area

    Well Control Response Actions Failed to

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    Well Control Response Actions Failed to

    Regain Control of the Well

    Had the 14 overboard line been utilized,

    as it should have been for any significant

    gas event, the outcome may have been

    different.

    The slip joint packer may still have been

    at risk, but a significant portion of the gaswould have been vented safely away,

    reducing the chance for ignition.

    Manual activation of the high-pressure

    BSR or the EDS would have been much

    more likely

    Emergency BOP Functions Failed to

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    Emergency BOP Functions Failed to

    Secure the Well

    Emergency BOP Functions Failed to

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    Emergency BOP Functions Failed to

    Secure the Well Manual emergency functions had beenrendered inoperable by the explosion

    and fire

    The AMF (Automatic Mode Function,more commonly called the Deadman

    System) then became the second to last

    line of defense. At a minimum this

    function would have activated the high

    pressure BSR.

    The Deadman System requires a loss ofcommunication, electrical power and

    hydraulics (all three) at both pods to

    activate.

    Communication and electrical power

    would have been lost with the MUX

    cable damage

    Although more protected, the hydraulic

    supply conduit and surface system

    would have been destroyed as well, if

    not by the explosion, then by the fire.

    The Deadman System failed to

    function

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    Tracking Info Here46

    Emergency BOP Functions Failed to

    Secure the Well

    On this model BOP Stack, the Deadman System relies

    on lithium battery packs in the subsea control pods to

    operate the solenoid valves.

    When these pods were recovered to the surface

    during the response effort, the Deadman System

    functions in both were found inoperable.

    In the Blue Pod, the battery power remaining was

    significantly below that required to operate thesolenoid valve.

    In the Yellow Pod, there was probably sufficient

    battery power, but the solenoid valve was inoperable.

    How much attention is given to the lines of

    defense that are considered last or next to

    last, especially when there are several

    barriers before these are needed?

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    Tracking Info Here47

    Emergency BOP Functions Failed to

    Secure the Well

    ROV Intervention also failed to secure the well

    The shuttle valves on the Cameron BOP Stack require a minimum flow

    rate to fully shift and direct fluid to the intended function.

    ROV Intervention capability is routinely tested at surface, but it is

    typically done with a hot line pulling fluid directly from the rigs

    accumulator system. It is seldom done with or at a rate equivalent to

    what the ROV pump can generate.

    The rate the ROV could generate was insufficient to shift the shuttle

    valves on this stack. This was due to the design of the shuttle valves

    and hydraulic leaks subsequently discovered in the system.

    The ROV successfully activated the autoshear function (if armed, this

    function activates the high pressure BSR when the LMRP is

    disconnected) by cutting the indicator rod. This was done 07:40, 21

    April 2010.

    The high pressure BSR failed to secure the well, and this was the last

    line of defense. Additional attempts were made to actuate

    components with the ROV intervention panel. It was assumed that

    attempts to close the pipe rams meant the middle VBR, but it was

    discovered that the bottom, inverted test ram was the one actually

    plumbed to the ROV intervention panel.

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    Tracking Info Here48

    Emergency BOP Functions Failed to

    Secure the Well

    Failure of the autoshear function, which closes the high-pressure BSR, to secure the wellmay have been due to:

    1. Insufficient hydraulic power to shear the 5-1/2 21.9 ppf, S-135 which was across the

    stack at the time of the incident

    2. Seal failure due to prevailing flow conditions in the BOP

    3. Presence of non-shearable components across the BSR

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    Tracking Info Here49

    Emergency BOP Functions Failed to

    Secure the Well

    1. Insufficient hydraulic power to shear the 5-1/2 21.9 ppf, S-135 which was across the

    stack at the time of the incident

    Period of approximately 30 hours existed where the subsea accumulators were

    not being charged from surface (explosion to ROV autoshear activation)

    During subsequent control efforts, a control system leak of no greater than 0.32gph was determined between pod retrieval and reinstallation.

    The investigation team stated that a leak of approximately 3 gph for 30 hours

    would have been required to drop the subsea accumulator pressure below that

    required to shear the drill pipe.

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    Tracking Info Here50

    Emergency BOP Functions Failed to

    Secure the Well

    2. BSR seal failure due to prevailing flow conditions in the BOP at the time of actuation.

    BSR successfully tested during the positive pressure test on the morning of the

    incident

    The exact flowrate at the time of actuation is not known, but the effect of closing

    the BSR under what may have been high flowrates is unknown. Much later in theresponse a rate of 53,000 BOPD was observed, but this was under different

    conditions at surface (and probably TD).

    The investigation team stated that with the leak observed in the hydraulic circuit,

    the shearing operation would have taken 17 seconds to complete. Without the

    leak, it should have taken 14 seconds.

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    Tracking Info Here51

    Emergency BOP Functions Failed to

    Secure the Well

    3. Non-shearable components were across the BSR at the time of actuation

    Pictures from later in the response effort showed two distinct drill pipe stubs in

    the riser section that was cut. This immediately raised questions regarding what

    exactly was across the stack when the BSR were activated.

    Through examination of the recovered stubs, the investigation team concludedonly one string was across the stack at the time of the BSR activation. Erosion, rig

    drift and hoisting equipment movement likely resulted in pipe movement and

    parting of the string above the BOP.

    The location of tool joints relative to the BSR at the time of actuation is not known

    exactly.

    Results from the physical inspection of the subsea BOP have not yet been

    released, but may shed more light on this subject.

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    Tracking Info Here52

    Emergency BOP Functions Failed to

    Secure the Well

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    Emergency BOP Functions Failed to

    Secure the Well

    Recommendations

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    Tracking Info Here54

    BPs Investigation team published 25 recommendations, specific to 8 key findings, in the Deepwater

    Horizon Incident Investigation Report. I would encourage you to read these and determine if and

    how these may apply to your operations.

    Since BPs recommendations are, in some cases, specific to their structure and culture (and maybe

    influenced by other objectives), lets cover some broader and a few deeper recommendations

    Recommendations

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    In the weeks and months following the Macondo Incident, the industry focused on Prevention. The

    government then demanded similar focus onSpill ContainmentandSpill Response.

    The immediate focus on Prevention is both understandable and warranted. We have all heard that Anounce of prevention is worth a pound of cure. An ounce of prevention would have been worth at least

    62 lbs of cure in the case of the Macondo incident.

    The same philosophy holds true when focused entirely on the multiple layers ofPrevention that we

    rely upon. The earlier in the layers of defense that an issue is recognized and aggressively addressed,

    the more efficient and reliable the response will be.

    Recommendations

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    Tracking Info Here56

    Barrier Philosophy

    Maintaining control of fluids, both produced and injected, throughout the life-cycle of a well is of

    primary concern and is a basic expectation.

    The design, installation or use, and proper verification of barriers is critical to meeting this expectation.

    Examples:

    If cement is going to be relied upon as a barrier, then achieving this becomes the primary objective

    in the design and execution. If trying to meet other needs that may jeopardize the barrier

    objective, the ability of the cement to perform as an effective barrier should be rigorously verified,or another barrier should be installed and tested.

    Safety-critical tests should be as simple and straight forward as practical, not encumbered by steps

    that could contribute to the misinterpretation of deviations from the expected. The reasons for

    deviations from the expected should be adequately investigated, the risks assessed if needed, and

    mitigation efforts implemented before proceeding.

    Recommendations

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    Tracking Info Here57

    Secondary and Emergency Control systems should be understood and tested.

    Deficiencies or failures in these systems should be either remedied or risk assessed. If the risk

    assessment concludes it prudent to proceed, the implications should be well understood by those

    potentially relying on the system.

    If another use or configuration exists for a safety-critical system, but this use or configuration may

    create additional hazards, the circumstances under which the alternate use can be employed must be

    well defined and understood.

    Examples:

    How much attention is given to the lines of defense that are considered last or next to last,

    especially when there are several barriers before these are needed (Deadman, autoshear and ROV

    intervention)? At least in the GOM, this is soon to be mandated.

    A diverter system is designed to divert flow safely away from personnel and the facility while

    minimizing the pressure on components with low pressure ratings. With the prevalence of SBM

    usage in the deepwater environment, the ability to route the diverter to a MGS became common.

    The diverter should direct flow directly overboard through a large ID line to avoid over pressuringthe slip joint packer, diverter element and marine riser components. Since SBM cant be discharged,

    and gas has the ability to go into solution (oil phase of the mud) and then be liberated near surface,

    the use of the MGS to control relatively minor solution-gas events (bottoms up after a trip, extensive

    sampling operations, or controlling a kick) has been widely accepted. Routing returns to the MGS

    during a major event, however, poses significant hazards. In the case of the Macondo incident,

    this action may have resulted in the death of 11 people and the elimination of some critical

    barriers that are typically relied upon.

    Recommendations

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    Tracking Info Here58

    Culture

    In the days following the Macondo incident, most

    companies immediately searched for assurances that this

    could not happen to them. I wont speculate on how manyassurances were made.

    The established processes that BP had in place

    (documented reviews, management of change, basis of

    design) are impressive. Unfortunately, these failed to

    prevent 11 deaths and a spill of national significance.

    Although harder to define and measure, and even more

    difficult to regulate, we pointed to our culture as the

    single most important differentiating attribute when

    comparing us to BP.

    In a recent meeting with an individual who has numerous

    dealings with BP, he observed that regardless of the

    purpose of the gathering (planning session to morning rigcall), it is almost impossible to determine who is ultimately

    responsible and accountable for the operation being

    discussed. Evidence of this exists in the very report this

    presentation was derived from.

    Recommendations

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    Tracking Info Here59

    In a White Paper presented to the BOEM, we presented what Marathon considered appropriate

    safeguards to have in place in order to resume operations in the GOM. The language below comes

    directly from that letter and was drafted by Greg Sills (VP Upstream Developments). Additional

    comments are shown in blue:

    The BP incident serves as a stark reminder, however, that systems and expectations are not enough nomatter how well presented a culture that encourages the appropriate leadership and individual

    behaviors is perhaps even more important. We intend to continue to reinforce the culture of a highly

    reliable organization that sustains attributes such as the following:

    A preoccupation with deviations, lapses, errors responding quickly and rigorously to anything

    which falls outside expectations, and refusing to recalibrate expectations in order to avoid

    normalization of deviance. (Opposite responses during the negative test, yet rationalizedand dismissed; continued warning signs during the displacement that well integrity did

    not exist)

    A listening environment where leaders listen to the front line and defer to expertise, faint signals

    are heard, and the front line reports confidently - even (especially) when the report is troublesome.

    (Our established culture of brutally honest reporting)

    Certainty is created where possible standard procedures are followed, not circumvented -creating excess capacity for dealing with the truly unexpected. (One of the reasons that drove

    the creation of our Design and Operating Guidelines unless you have obtained proper

    approval for a deviation, the established standards will be followed so attention can be

    focused on other areas)

    These are examples of a responsive and agile organization that detects small misjudgments early,

    notices the unexpected while it is still forming, arrests it before it expands, and safely returns to normaloperation.

    Recommendations

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    .

    Final Thoughts:

    Responsibility and Accountability. Focus and awareness increase when you know that you are bothresponsible and accountable. Take the earlier points made when discussing well monitoring:

    As long as the BOPs and Marine Riser are attached to the wellhead, a conduit directly to the rig

    exists. As long as a direct conduit to the to rig exists, constant monitoring to ensure well control is

    maintained is required. The Driller is ultimately responsible, regardless of the other operations

    going on, for ensuring well control is maintained at all times.

    Would an influx of 1,000 bbls over 49 minutes occur undetected if the Driller truly understood and

    believed this?

    False Sense of Security. We must always guard against complacency in the absence of recent

    consequences. For years the industry bragged that there had never been a deepwater blowout of any

    significance. Last line of defense safety systems went years without ever being needed. Guards were

    lowered. We must maintain a sense of vulnerability.