THE damage done by a tanker to an oil depot pier on Tsing Yi Island will take a month to repair, according to the Nga Ying Chau Depot's manager. The collapsed part was a structure that supports more than 10 pipes for the transfer of diesel, heavy oil and industrial solvent onto oil tankers. About 400 litres of diesel spilled into the sea but was handled with relative ease, according to pollution controllers. The accident happened on Wednesday evening when the 18,480-tonne Panama-registered Patriot turned after unloading and knocked off part of the pier. Newly-elected district board members for northern Tsing Yi said they had been lobbying for the removal of the depot since 1990. 'The incident showed that accidents are possible and justified our worries all along. We are lucky this time because it happened on a minor scale but it's hard to imagine how big the potential risks are,' said Albert Wong Cheong-shing.