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Audit of drilling and well activities on Oseberg

During the period 9-12 November 2004, the Petroleum Safety Authority Norway (PSA) conducted an audit of Norsk Hydro's (Hydro's) follow-up of drilling and well activities on the Oseberg field. The drilling facility on Oseberg B has been in use for nearly 18 years, and the plan calls for the facility to continue operations for another 10-15 years. The objectives of the audit included verification of whether the facilities are of adequate quality, and that adjustments in operations and maintenance in recent years are satisfactory in relation to applicable regulatory requirements.


Background for the audit
In the award letter from the Ministry, the Petroleum Safety Authority Norway (PSA) is ordered to contribute to reducing the risk level in the offshore petroleum activities by following up to ensure that the players facilitate the technical and operational integrity of the installations.

The drilling facilities on Oseberg B have been in use for nearly 18 years, and the plan is to use them for another 10-15 years. The background for the task was to verify whether the facilities are of sufficient quality, and that adjustments of operations and maintenance in recent years are satisfactory in relation to the applicable regulatory requirements.

Another desirable objective was to prove that operational procedures and programs for the activities are safeguarded, and that the status of well integrity is in accordance with the level of prudence required in connection with risk factors in the drilling area.

Purpose of the audit
Our objectives are to verify that Hydro acts as a responsible operator for the activities and

  • ensures internal notification of incidents in the drilling area, as well as ensures that they are followed up in accordance with Hydro's internal requirements and regulatory requirements.
  • ensures transfer of experience so that the HSE work entails genuine worker participation in weekly safety meetings, in shift meetings, in pre-job/job execution meetings and in the performance of safe job analyses (SJA).
  • ensures that procedures are updated in relation to ongoing activities, that manning, capacity and competence conform with the needs and the roles and responsibilities in various positions are handled appropriately.
  • ensures that technical documentation and updating of the maintenance systems are safeguarded.

Result of the audit
Hydro personnel on land and on the installation were well acquainted with the HSE objectives established to achieve safe operations in the drilling area. However, not all employees of the drilling contractor were sufficiently aware of these objectives, including the safety delegate service.

One effect of this was that the safety delegate (VO) meetings and HSE meetings were not taken sufficiently seriously by all personnel.

Our report addresses the operator's duty to involve the drilling contractor and well service companies in this work.

There was a potential for better efforts in a larger group in the safety work between Oseberg B and the Oseberg Field Center, which could spur an improved commitment in the local HSE work as regards drilling.

Several measures have been initiated in the fall of 2004 to strengthen HSE work on Oseberg B.

One important measure has been to implement internal courses in inspections on board the installation. Another measure is the work on the "Safe Drill Floor" project.

The method used in this connection has been well-received on board. In addition come the drilling crew's efforts to report incidents in the new follow-up system, SynergiX.

Significant willingness to make reports and focus on reporting one's own mistakes has led to a change in attitudes and behavior and may actually be one of the reasons for fewer serious incidents.

Two new positions have been implemented, a safety supervisor and an operations planner in the drilling discipline on Oseberg B. Our interviews confirmed that these positions are partly responsible for the progress that has been recorded.

We also take a positive view of the measures implemented to improve the working environment, with noise-reducing measures in the mud treatment unit and the mud vacuum cleaner in the pump area.

For Oseberg B, short-range well targets will be practically non-existent in the future. Drilling of formations at the extreme edges of the Oseberg field is more demanding, and the distances to the well targets will be greater.

These two parameters are important in relation to the capacity of the drilling facility. In order to meet the challenges of the future with 10-15 more years of drilling activity on Oseberg B with long-range, complex wells, the drilling facilities will require a substantial upgrade in 2005 - 2006.

One of several indicators of this was low efficiency in the unit with a significant downtime hours in 2004.

Contact person i the Petroleum Safety Authority
Mike Theiss