Elgin G4 Leak

25 March – 16 May 2012

Elgin: key facts & figures

2

On stream since 2001

6 producing wells from 4 HP/HT fields

Produced 135k boe/d in 2011

Operated by Total for 8 x JV partners

Production Utilities Quarters (PUQ) & wellhead platforms linked by 90m bridge

Elgin G4: well architecture

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Well head deck on Elgin ‘A’ platform

Seabed @ 93m below platform

Chalk HOD non-producing

low permeability high pressure

Fulmar producing

high permeability lower pressure

25 Feb: sudden decrease of A annulus pressure and rapid increase in B and then C annulus

G4 Task Force established: well intervention prepared with Rowan Viking rig support

15 March: tubing and A annulus contents displaced to 1.2sg brine

22 - 25 March: well killing

start pumping 2.05sg OBM down tubing & up A annulus B & C annuli pressure increase

C annulus bled off through WHP process B annulus operating window increased

after 172m3 operation suspended as mud returns to the process via C annulus

attempt to re-route C annulus returns line to surge tank

sudden unsustainable C & B annuli pressure increase - leading to gas release at well head D annulus

Elgin G4 leak: build-up

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Specialised team mobilised to complete thorough incident investigation

Elgin G4 leak: day one (25 March)

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12.20: gas & condensate leak confirmed at the wellhead on Elgin’s G4 well

13.30: evacuation begins of Elgin and the adjacent Rowan Viking drilling rig

16.40: 219 people have now been evacuated – leaving 19 still on the complex

01.45: Elgin OIM decides to fully abandon

Platform, rig & wells shut down - but flare still lit

Export pipelines isolated

02.30: the last 19 people are evacuated

All 238 people safely and quickly evacuated

Elgin G4 leak: initial impacts

Gas, condensate & mud released via D annulus

Visible gas plume formed

Condensate & mud falls to sea

Sheen covers a large area of sea surface

Waxy paraffinic deposits on wellhead platform

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Elgin G4 leak: initial response

Informed all appropriate Authorities

Mobilised Emergency & Crisis Response Teams

Oil Pollution Emergency Plan (OPEP) activated

Enforced sea & air exclusion zones (2 & 3 N miles)

Mobilised a fleet of safety & support vessels

Dispersant ships and planes put on standby

Recruited Wild Well Control to assist

Mobilised Oil Spill Response Limited (OSRL)

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The Skandi Aker well intervention vessel

The Ocean Ness Emergency Response & Rescue Vessel

Elgin G4 leak: options to regain well control

Preferred Option: a pumped well kill operation a mobile pumping unit putting heavy mud directly into G4 from the wellhead

technically feasible

re-boarding of the Elgin wellhead platform necessary

Wild Well Control already mobilised and suitably experienced

no absolute guarantee of success

timescale measured in weeks

Back-up Option: drill a relief well a contingency in the event the well kill is ineffective

technically feasible

start drillng two wells and use the one that reaches the interception point first

two drilling rigs (Rowan Gorrilla V & Sedco 714) already on Total’s books

success virtually assured

timescale measured in months

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Elgin G4 leak: options to regain well control

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Elgin G4 leak: post incident milestones (1)

29 March: OSRL flights reveal size of sheen has already diminished considerably

30 March: flare is confirmed as extinguished

2 April: well kill & relief well options announced

5 April: first re-boarding of Elgin complex by Wild Well Control & Total E&P UK teams

15 April: mobilisation of West Phoenix drilling rig & Skandi Aker as main well kill support vessels

18 April: Sedco 714 spuds first relief well

26 April: special ‘diverter’ fitted to G4 well head

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The Sedco 714 drilling rig

The diverter on the G4 wellhead Fitting the diverter was ‘a game changer’

Elgin G4 leak: post incident milestones (2)

Successful removal of waxy deposits

Laying of 230m of ‘chiksan’ pipeline

10 May: West Phoenix drilling rig alongside

10/15 May: extensive equipment testing

15 May: Well kill operation begins

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Daily cleaning operations on the Elgin well head platform

The West Phoenix; the main well kill support vessel

‘Chiksan’ temporary rigid pipeline

Elgin G4 leak: well kill set-up

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Pre-kill testing, using Coflex from West Phoenix to Elgin PUQ

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Elgin G4 leak: well kill operation

Nearing the end of the well kill operation

Elgin G4 leak: well kill operation

Dynamic well kill with 2.05sg mud

Initially pumped water based mud (WBM)

Pumped through G4 wellhead into tubing

1000m3 pumped @ a rate of 8-12bbls/min

Pumped via Coflex & chiksan from West Phoenix

Pumping for 12 hours

No diversion: pumped fluids exited to sea

After 5 days, WBM replaced with oil based mud

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G4 now stable and under observation

Elgin G4 leak: current status

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The well has been ‘killed’ and is filled with oil based mud

The well & gas leak path are under control

Progressive re-manning of the Elgin complex & the Rowan Viking is underway

The West Phoenix will be demobilised once the Rowan Viking’s pumps are available

As a contingency, drilling of relief well 1 to continue for now

But a decision taken not to drill relief well 2

Other Elgin/Franklin wells being monitored

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Elgin G4 leak: environmental impacts

Widespread consensus that the environmental impacts are minimal

Environment Monitoring Activities

2 Oil Spill Response Limited (OSRL) flights per day to monitor marine pollution

Regular survey flights by the National Centre for Atmospheric Science (NCAS)

Daily water samples taken in Elgin surroundings

Leak flow rate estimated at an initial 2kg/s but quickly fell to less than 0.6kg/s

Gas composition: 70% methane + 30% ethane, butane, etc; no H2S traces

Surface sheen extended many kms, but was less than 1/10th of a micron thick

Light condensate that disperses naturally and easily: 50% evaporation in the first 24 hours alone

Several independent chemical, sediment and & fish analyses confirmed no direct marine contamination (eg, Scottish Government, etc)

Elgin G4 leak: next steps

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Fully re-man the Elgin complex, including on-board sleeping, etc

Re-man the Rowan Viking drilling rig and get its pumps working

Continue to deep clean the Elgin complex, power up & test on board systems

Demobilise the West Phoenix (when Rowan Viking’s pumps are working)

Set a 50m cement plug in well G4 as part of abandonment process

Stop drilling relief well (when cement plug in place)

Co-operate fully with on going HSE investigation

Work towards gradual resumption of normal operations

Adopt lessons learned and share with the wider industry

Thank you for listening

… any questions?