NEB Begins Sable Gas Abandonment Process

Canada’s National Energy Board (NEB) has begun the regulatory process to abandon the undersea pipeline, a short on-shore pipeline and the Goldboro gas plant, which processes natural gas from ExxonMobil Canada’s depleted Sable Offshore Energy Project (SOEP).

ExxonMobil Canada applied to the NEB in late March this year for abandonment approvals, and the board is now asking interested parties to apply to participate in the process, which could include public hearings later this year.

At its peak, SOEP produced some 500mn ft³/day of natural gas from 21 wells on seven platforms, drawing reserves from five fields – Thebaud, Alma, North Triumph, Venture and South Venture. The project, operated by ExxonMobil Canada with partners Shell Canada Energy, Imperial Oil, Pengrowth Energy and Mosbacher Operating Limited, commenced production in December 1999.

The 200 km undersea pipeline will be cut at its landfall and at its connection to the Thebaud platform, deinventoried of residual hydrocarbons, flushed and refilled with sea water and sealed at both ends. It will remain marked on navigation charts.

The 2 km onshore portion of the pipeline will be deinventoried of residual hydrocarbons, flushed with sea water, isolated and filled with grout. Above-ground facilities associated with the pipeline will be removed.

The gas plant will be deinventoried of residual hydrocarbons and all above-ground infrastructure dismantled and removed. Below ground infrastructure will also be removed, with the exception of water wells, which will be plugged and abandoned, while remedial work will be undertaken to address soil contamination, if required.

ExxonMobil began plugging and abandoning the offshore wells in December 2017, a process expected to take two years. After all wells have been abandoned, the seven platforms will be decommissioned and removed under the regulatory supervision of the Canada-Nova Scotia Offshore Petroleum Board.