By Andrew Callus
LONDON Feb 14 Last year's leak from the Elgin
gas platform tapping one of the world's most highly pressurised
fields was caused by a "unique" interaction of rock compaction
and pipe corrosion, according to the field's operator.
French oil company Total said the leak, which was
discovered in March and took over seven weeks to plug, happened
when the compaction caused unusual pressures higher up,
eventually breaking pipework weakened by corrosion. The field
has been shut ever since.
Patrice de Vivies, Chairman of Total Holdings UK, put the
corrosion down to a chemical reaction between bromide in the
drilling fluid used to complete the well and grease in the
De Vivies said what happened was "a unique event", but
added: "We will be much more conservative in future in the
pressures we can meet from the well."
Total plans a full report on the causes of the incident.
Vallourec, which makes the pipes used at Elgin and
other fields around the world, also called the corrosion
"unique" and said the incident "does not question the quality of
De Vivies was speaking at a post-results news conference in
London on Thursday at which Total chief executive Christophe de
Margerie said he expected to receive a letter "in the next days"
from Britain's Health and Safety Executive (HSE) that will allow
it to restart Elgin soon.
"HSE has received the safety case (from Total) and is
considering its response," a spokesman for Britain's Health and
Safety Executive said.
De Vivies said that the company expected the Elgin-Franklin
oil and gas field to produce 140,000 barrels of oil equivalent
by 2015, and raise output to 150,000 barrels by 2016.