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

Notice No. 007

November 16, 1973

OCS Operations Safety Alert

Lack of Adequate Supervision by Lease Operator of Contract Personnel

A pollution incident recently occurred on an OCS installation where a well was left unattended with the subsurface safety device removed, the master valve open, the wing valve open, and the flowline disconnected.

The well's tubing string was to be used for orientation of perforations in another tubing string.

The well was supposedly dead; however, in order to pull the tubing plug, a contract well control unit was used to pressure up with salt water above the tubing plug. The tubing plug was then pulled by the contract wireline operator; however, due to the lack of additional required equipment and the approaching end of daylight, the contractors (both wireline and well control companies) were ordered by the lease operator's workover superintendent by radio to cease operations and secure the well.

The wireline operation rigged down, shutting the crown valve. The well control unit rigged down, leaving the wing valve open and the flowline disconnected. The contract personnel departed the platform at approximately 5:30 p.m. The wireline operator stated on his work order, "well secured."

During the night, the well unloaded and was discovered to be flowing at approximately 2:00 a.m. by a night pumper during a routine inspection by boat. (This well is presently a flowing oil well without any additional workover.)

The lease operator had in effect a protection plan which stated, "Wireline - Electric Line; line not in hole --- Master Valve closed." However, none of the lease operator employees checked to confirm that the plan was carried out, nor were any of the contract employees assigned as being in charge of the workover and therefore directly responsible to the lease operator for the entire operation.

Recommendations which were made to prevent a recurrence of this pollution incident are:

1. Establish a procedure whereby the lease operator's personnel secure each unmanned platform after or during the departure of all other personnel.

2. A night inspection procedure of unmanned platforms, assuring at least one inspection per night, with the exception of inclement weather qualification.

These recommendations should be reviewed by all operators for applicability to their OCS installations and operational procedures.

[signature] D.W. Solanas

Oil and Gas Supervisor

Field Operations

Gulf of Mexico Area