Elgin Gas Release
15 April 2012
Introduction
Total S.A. is a large multinational oil and gas company created
in France in March 1924, they employ over 90,000 people worldwide
and operate in over 130 countries. They have interests in the oil
and gas industry upstream and downstream, as operators or in joint
ventures with other oil and gas companies such as Esso, Texaco,
etc.
A subsidiary of the Total group is Total
E&P UK PLC, one of the UK’s largest oil and gas operators. They
operate several installations including Alwyn North, Dunbar, Ellon,
Elgin and Franklin fields. Since 2002 they have had ten improvement
notices from HSE, two of
which were for the Elgin Franklin in 2006 and no prosecutions.
Purpose
The purpose of this note is to apprise
interested parties of the background to and on-going status of the
gas release incident of 25th March 2012 and to capture
key lessons in due course
Elgin/Franklin
The Elgin field is a high pressure high
temperature field located in the Graben Area, of the central north
sea around 240Km from Aberdeen. It was discovered in 1991 at a
depth of around 93 metres. The combination of high pressure
and high temperature was a difficult challenge for Total at that
time and resulted in the design of the ESDVs (emergency shutdown
valves) taking five years and at the time they were the
largest in the world. Drilling on the five production wells and
reconnecting two exploration wells, was carried out by the Santa Fe
Galaxy 1 with well pressures between 650 -1100 Bar.
Production commenced from the Elgin field
in March 2001 with gas being exported from May that year,
within 12 months the Elgin and Franklin fields combined provided 13
million m3 /day of gas and 140,000 barrels of
condensate, combined equating to 220,000 of oil. The well
head platform is a steel jacket four leg design connected to the
production, utilities and accommodation (PUQ) platform by a bridge.
The well head platform is normally unmanned and operated from the
PUQ control room as is the Franklin well head platform. Gas from
the Elgin field is exported via the SEAL pipeline to Bacton and
into the UK national grid. Gas from the Franklin and Shearwater
also is exported using the same route.
On the 25th March 2012 around noon
well control problem resulted in a gas release, and the decision to
evacuate non essential personnel from the platform and neighbouring
Rowan Viking drilling Jack up was made.
A sequence of Total events is listed at the
end of this article based on the press releases on the total
incident web site,
other significant events are precautionary down manning of non-
essential personnel on the neighbouring Shearwater and Hans Van
Duel installations
Incident related articles
Total Stops
Elgin Gas Leak
Total Begins
Elgin Well-Intervention Operation
Total Incident website
Elgin
leak 'signals decommissioning woe'
Total prepares parallel operations to stop Elgin gas leak
Gas cloud encircles Total's Elgin-Franklin platform- union
No Indication
Total Gas Leak has had Significant Environmental Impact
Advanced
Drilling in HP/HT: Total’s Experience on Elgin/Franklin (UK North
Sea)
Elgin-Franklin hub was producing 10% of UK's gas before
leak
Shell
completes shutdown
Total knew of gas leak fears four weeks ago
Incident chronology based on Total press
releases
|
Date/Time
|
Events
|
|
25/03/12
|
|
~ 12:15
|
Gas release
|
|
~14:00
|
Evacuation
|
|
~16:45
|
Viking personnel evacuation onshore, Non
essential PUQ personnel evacuated to neighbouring platforms
|
|
~18:45
|
Efforts to control release, non essential PUQ
personnel moving to onshore
|
|
~23:00
|
All 238 Personnel accounted for no injuries,
150 personnel onshore, 69 neighbouring platforms, 19 crew still on
PUQ,
OPEP activated,
Sheen on water seen
|
|
26/03/12
|
|
|
~03:28
|
19 core PUQ crew evacuated onshore, air
spotter plane due 07:30 for sheen
|
|
~14:25
|
Experts being mobilised to assist
|
|
~21:00
|
Situation stable, no change in sheen
size/composition,
SOSRep mobilised
|
|
28/03/12
|
|
|
~16:00
|
Gas cloud visible from spotter plane, sheen
unchanged, fire fighting and ROV vessels on standby, cause still
unknown
|
|
~18:25
|
Lit flare burning wind direction away from gas
cloud
|
|
29/03/12
|
|
|
~19:00
|
Gas leak ongoing, well experts mobilised,
thought leak from well formation above reservoir, volume gas
unknown moving away from platform
|
|
30/03/12
|
|
|
~13:30
|
Two potential solutions to leak blocking the
well and relief well drilling
|
|
~18:30
|
Situation stable five days,
Two main solutions are being progressed. The
first is to pump heavy mud directly into the well and the second is
to drill relief wells to intervene at the source of the gas
flow,
Sedco 714 and Rowan Gorilla V available to
drill relief wells,
gas leak estimate to be around 200 000 m3 of
gas per day,
Exclusion zone set up
Sheen reducing in size
Flare diminishing
|
|
31/03/12
|
|
|
~12:00
|
Flare extinguished
|
|
02/04/12
|
|
|
~12:00
|
Talks to board platform
|
|
05/04/12
|
|
|
~10:30
|
Helicopter dispatched to platform with well
control team
|
|
~17:45
|
Well control specialists boarded platform and
carried out survey
|
|
06/04/12
|
|
|
|
No gas was found on the PUQ or access to, well
head 90m away
|
| 15/5/12 |
Oil is pumped into well |
| 16/5/12 |
Oil leak stopped |