Jotun Field, North Sea
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On Friday, 20 August 2004, there was a pressure drop in the gas export pipeline inlet from Jotun A as a consequence of a breach in the pipeline about 10 km from Jotun A. The gas flowed into the sea and reached the surface. The Petroleum Safety Authority Norway (PSA) investigated the incident and has issued two notifications of orders to ExxonMobil.
The incident was handled in a cooperative effort by ExxonMobil, Gassco and Statoil as "Technical Service Provider" (TSP).
Concerned parties were notified and kept informed in a correct manner.
The resources required to close the leak were made available. On Sunday morning, the leak was closed with the help of a remote-controlled subsea vessel (ROV) which closed the valves at Statpipe.
The actual safety and environmental consequences of the incident were limited, although this incident, and all such similar incidents, have the potential of significant safety consequences.
The Jotun field is located about 165 km west of Haugesund. The water depth on the field is 126 meters.
The field is developed with a manned production facility (Jotun A, production ship) and a permanent wellhead installation which is not normally manned (Jotun B).
The oil is transported by shuttle tankers, while the gas is exported with the aid of a pipeline from Jotun to Statpipe.
Investigation of the incident:
Our investigation identified barrier failures and barrier weaknesses related to installation and inspection of the gas export system, and ExxonMobil's handling of the incident, as well as barrier weaknesses on the part of Gassco associated with how the incident was handled.
We have found non-conformities in relation to the petroleum regulations, which the PSA takes very seriously.
These non-conformities are primarily linked to two factors:
Non-conformities in connection with how the hazard situation was handled in relation to the breach of the gas export pipeline. Warnings concerning the hazard situation on board were indicated by both a low pressure alarm on the export pipeline, and a development showing declining pressure 25 minutes prior to this alarm. Production continued simultaneously with work to clarify the hazard situation, and was not shut down until nearly three hours later. Deficiencies have also been identified as regards the communication between Jotun A and the emergency response management on land about ongoing operations on the installation during this time period.
Flange abandoned on the seabed in an exposed condition, and this non-conformity was not identified/processed in the company's own system for handling non-conformities. We have also identified deficiencies in subsequent inspections of the pipeline that did not reveal that the flange was to have trawl clearance.
On this basis, ExxonMobil has been notified of the following orders:
Pursuant to Section 13 of the Framework Regulations relating to the duty to establish, follow up and further develop management systems, Section 68 of the Activities Regulations relating to handling of situations of hazard and accident, and Section 58 of the Framework Regulations relating to individual decisions, ExxonMobil is ordered to review its management systems related to handling of hazard and accident situations to ensure that necessary actions are taken in connection with the handling of such situations.
Pursuant to Section 13 of the Framework Regulations relating to the duty to establish, follow up and further develop management systems, Section 24 of the Framework Regulations relating to Development concepts, Section 20 of the Management Regulations relating to Handling of non-conformities, Section 44 of the Activities Regulations relating to Maintenance programs and Section 58 of the Framework Regulations relating to Individual decisions, ExxonMobil is ordered to review its management systems to ensure that necessary evaluations related to the trawl clearance requirement are implemented in connection with development and operations in the petroleum activities. Among other things, this review must ensure that established systems for handling non-conformities are implemented, and that the maintenance programs developed can prevent error situations that are caused by external factors such as fishing gear.
Our investigation report has also been sent to Gassco. We have asked the company to respond regarding our findings that relate to Gassco.