U.S. Department of the Interior Minerals Management Service Gulf of Mexico OCS Region

Notice No. 055

January 21, 1977

OCS Operations Safety Alert

Oil Spill -- Safety Equipment Failure

An oil spill occurred recently on an offshore production platform because of malfunctions of three safety devices.

A lead production pipeline pump transferring oil from a surge tank to a pipeline shut down because of a faulty vibration switch on the gearbox. A lag pipeline pump failed to start up because the timing circuit did not allow low engine pressure to clear the panel. This resulted in a high oil level in the surge tank. A high liquid level shut-in device on the tank failed to operate and accomplish platform shut-in. This failure was either because of excessive supply pressure overriding the magnetic force applied to the pilot valve or a relay valve in the panel shut-down circuit failed to trip. Approximately twelve barrels of oil was discharged through a gas vent line into the Gulf.

To prevent a recurrence of this accident the operator has taken the following action:

1. A new vibration switch has been installed on the lead pipeline pump.

2. The timing circuit on the lag pipeline pump box has been reset.

3. A new high liquid level shut-in device with an individual supply regulator has been installed on the surge tank.

4. The safety system panel has been modified in order that the end device shut-down circuit can be tested for proper operation.

[signed] D.W. Solanas

Oil and Gas Supervisor

Field Operations

Gulf of Mexico Area