Approach

First approach

As the blowout preventer was blocked, it was not possible to inject water at first. It had to be cooled off before it could be removed using a crane. But hydrostatic pressure alone turned out to be insufficient to close the blowout preventer. Time was pressing because leaks seldom remain stable and are capable of eroding.

One method of sealing leaks is to use rubber, rubber balls, or even golf balls as sealing elements in the gas stream. In this case, a mixture of water and rubber balls succeeded in stopping the escape of gas. A new blowout preventer was mounted. The emergency operation was successfully concluded within the space of two weeks.

Second approach

The second approach called for a relief well (emergency bore) to be driven about 300 m away. The plan was to pump sealing fluid into the well bore at a depth of some 1,500 m and thus curb the escape of gas. A period of two weeks was scheduled for the drilling. At a depth of about 300 m, however, the work was stopped because the strategy adopted first had already proven successful.

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