This follows the earlier reported fire at Patrick Waterside in Bodo, which a joint investigation team had confirmed was due to a hacksaw cut by unknown persons, the oil firm said in a statement on Wednesday.
The 28-inch line was shut in on October 14.
The other 24-inch line, which was shut in on October 9 following leaks at B-Dere and Nonwa-Tai, remains closed, Shell stated.
While investigations showed that unknown persons had drilled a hole on the 24-inch TNP at B-Dere, the joint investigation on the Nonwa-Tai spill is continuing and expected to be concluded soon, it added.
The company said preliminary findings indicated that the spill may have been caused by a failure on the pipeline.
SPDC said it had quickly mobilised its oil spill response team to the site and contained the spread of the spilled oil, adding, “Further remedial measures, clean-up and repairs are continuing. SPDC regrets this operational spill and is investigating the root cause of the failure.”
The company gave an assurance that it will continue to monitor the situation and the force majeure that was declared on Bonny Light exports on October 9 will be lifted as soon as it is operationally possible to do so.
SPDC had shut the TNP following reports of new leaks, about 10 days after the line was repaired from crude oil theft incidents.
Some 150,000 barrels of crude oil were deferred per day during the closure.
The firm, last month, reopened the pipeline after about two months of closure. The line supplies about 150,000 barrels of crude per day.
Shell had announced the reopening of the pipeline on September 8 this year.
The company had earlier shut the TNP in July following a leak on the Bomu-Bonny section at Owokiri, which was found to be caused by a six-inch crude theft valve placed on the line.
The shut-down came just days after Shell had re-opened the line following an explosion and fire in June at a point that had been targeted by oil thieves at Bodo West in the Niger Delta’s Ogoniland.
SPDC stated in July that it estimated the total daily loss from the TNP shutdown to be roughly $15m.
The closure of the line then had also hit Nigeria’s domestic power generation, with SPDC being forced to shut down the Afam VI power plant due to a shortage of gas arising from the closure of the pipeline.
Information from Punch was used in this report.