Disused Oil Wells

HC Deb 17 June 1996 vol 279 cc312-3W

Mr. Gordon Prentice

To ask the President of the Board of Trade how many disused oil wells in British waters(a) have leaked and (b) are believed to be leaking from the capped reservoirs into the sea. [33072]

Mr. Page

Only one well in British waters has leaked small quantities of gas—not oil—from a shallow horizon into the sea and remains uncapped. The well, 22/4b-4, was drilled by Mobil in November 1990.

It was not physically possible at the time, or subsequently, to perform any sort of intervention into the wellbore which would have any degree of success in plugging or killing the well. It has not, therefore, been capped.

Recent inspections and sampling by Mobil have confirmed that the fluid now leaking is water, which contains no trace of hydrocarbons.

There have unfortunately been three disasters where hydrocarbons have leaked into the sea: Piper Alpha, Ocean Odyssey, and Sea Gem. These leaked hydrocarbons for a short time only, until the occurrence was controlled.