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By Oleg Vukmanovic
LONDON, Sept 5 (Reuters) - Angola's new liquefied naturalgas (LNG) plant has pushed back the start of a 53-daymaintenance period to mid-September after engineers discoveredsmall gas leaks in onshore pipelines last month, sources linkedto the project said.
The $10 billion plant was initially due to shut on Aug. 18,but the discovery of two leaking wells led site managers todelay maintenance until the problem was traced and fixed, a siteengineer said.
The start-up of Angola's first LNG project, which convertsgas into a liquid form for export, suffered long delays as theplant was beset by various technical problems, including a firein April that occurred just hours before production was tobegin.
The Chevron-operated project eventually shipped itsfirst LNG cargo to Brazil in June, 18 months behind schedule.
Maintenance has now been pushed back until Sept. 13, thesite engineer said, while a second engineer at the plantconfirmed that maintenance was scheduled to start inmid-September.
"It will be 53 days from production to production after theplant shuts ... the maintenance is there to replace thestrainers and remove limescale and conduct a performanceacceptance test," the first source said.
Officials at Angola LNG could not be reached to comment.
As part of maintenance, engineering firm Bechtel must ensurethat the plant passes a performance test, hitting certainmilestones such as running close to its maximum capacity.
Angola LNG has so far exported three cargoes on tankers toBrazil, China and Japan, in that order, and traders wereexpecting a fourth and possibly fifth shipment from the plantprior to shutdown.
It is not clear whether there is enough LNG in its storagetanks to allow a fourth cargo to be loaded.
"Only if they produced more than expected, could they loadanother cargo. They have to keep some LNG in the tank to keep itcold during the shutdown period," the first source said.
Chevron holds a 36.4 percent stake in the project and Angolastate oil company Sonangol 22.8 percent, while Total,BP and ENI each hold 13.6 percent.
