PSA probes two North Sea well incidents

Oct. 14, 2020
Norway’s Petroleum Safety Authority is investigating two recent drilling incidents in the North Sea.

Offshore staff

OSLO, Norway – Norway’s Petroleum Safety Authority (PSA) is investigating two recent drilling incidents in the North Sea.

One occurred on Sept. 20 at the Gjøa field, operated by Neptune Energy. The drillstring of production well 35/9-G-4 H, drilled by the Odfjell-operated semisubmersible Deepsea Yantai, became stuck.

The well had already entered the reservoir section when the string got stuck in the formation while it was being pulled out. During attempts to free the string, it separated into two sections: these blocked the BOP, rendering it unable to close and prevent a potential wellstream leak.

However, no discharges are said to have followed, and according to Neptune,  a cement plug has been inserted against the reservoir in order to restore barriers. But operations continue to remove the two drillstring sections from the BOP.

The PSA has detailed an investigation team to look into the incident, focusing on the well planning and implementation of the drilling program up to the point when the incident occurred.

Its goal is to identify the causes and possible lessons to be learned.

The other incident, which occurred on Sept. 14, concerned a BOP on the Valaris jackup Rowan Stavanger, which was working for Equinor on the Gudrun field in the Norwegian North Sea.

During routine pressure testing of the BOP, the 1.9-metric ton (2.1-ton) door of the blind shear ram came loose and was shot from its position, landing 4 m (13 ft) horizontally and 1.35 m (4.4 ft) vertically from the BOP.

Although the area around the BOP had been cordoned off in connection with pressure testing, the loose component is understood to have landed outside the cordon, the PSA said. It plans to launch an investigation.

The PSA has also issued drilling consents to two operators. In the North Sea, Equinor will use the semisub West Hercules to drill a well and optional side track on the Blasto prospect in license 090, in a water depth of 39 m (128 ft), with the program potentially lasting 50 days.

KCA Deutag Drilling’s jackup Askepott will drill for Equinor on the Oseberg field.

Lundin Energy’s consent relates to a well in PL 609, to be drilled by Seadrill’s semisub West Bollsta.