Northern Region Director Capt Abdul Samad Shaik Osman said although a Port Klang-registered oil tanker was the suspected culprit, it was premature to say if the vessel was at fault.
He said the tanker had passed integrity checks and no leaks were spotted.
Samad said the Department of Environment had sent samples from the vessel and the affected waters to the Chemistry Department in Petaling Jaya for analysis.
He said the results of the tests were expected tomorrow.
Samad said preliminary investigations revealed that the oil spill could be accidental but did not say who was most likely at fault.
“Our officers are still looking to see if the leakage could have come from elsewhere,” he said when met by reporters at the Penang Port Commission today.
“We are also now investigating the inland fuel depot (also known as the bulk cargo terminal).
“The oil tanker remains berthed there.”
Samad said 600 litres of dispersant liquid were used to clean up the oil slicks.
(Dispersants are chemicals that break down oil into droplets that mix with water.)
On Friday night, the oil tanker was suspected to have released fuel oil at the Prai Bulk Cargo Terminal. It was the only vessel there at the time.
The spill caused 77 sq km of the North Channel, the area north of Penang Bridge, to be polluted with oil slicks.
A clean-up team, involving personnel from oil companies, bunkering facility, port authorities and the Marine Department, managed to clean up the spill by Saturday evening.
Meanwhile, Malaysia Nature Society warned the clean-up did not mean anything as the oil could have done irreversible damage to nature and fouled up Penang’s coasts.
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