Liquid pitch, which began leaking from a large storage tank on Saturday February 18 ran at a rate of about 2t/hour. More than 280t of the pitch, used in the smelting of aluminium, had leaked by Tuesday Feb 21.

State Emergency Service volunteers have been sandbagging the area to contain the material.

Preparations have begun to arrange the transfer of the remaining contents of the tank to a ship, which is expected to arrive on Wednesday or Thursday.

The Koppers facility, built in 1994, is situated on land leased from the Port of Portland.

Coal tar pitch is used in the manufacture of carbon anodes for the aluminium electrolysis process. The material is stored at elevated temperature and solidifies at ambient temperatures.

So far, all material has been contained within the tank farm area with no release of material to water or soil.

The incident is being coordinated by the Country Fire Association in conjunction with other local authorities and is being monitored by the Australian Environmental Protection Authority.

Koppers has been and will continue to work closely with the responsible local authorities, customers, suppliers and insurance advisors.