The driver pulled the semi-trailer over on the New England Highway, near Bendemeer, about 1am on Thursday after the cabin filled with smoke.

The driver tried to extinguish the blaze which took hold and called Triple Zero before RFS and Fire and Rescue NSW crews were deployed to the scene.

Fire and Rescue NSW Superintendent Tom Cooper said the RFS crews were first on scene and knocked the blaze down before Hazmat crews took charge of the operation to unload the goods.

“The front half compartment of the trailer had started to catch fire and that contained a whole heap of dangerous chemicals,” he said.

“The fire melted a lot of the containers and ran onto the roadway and into a culvert.

“Fire crews in spillage suits and breathing apparatuses were able to unload a majority of the containers and the contents of which were placed in hazmat bins.

“The crews rotated through the site in spillage suits which is pretty arduous work.”

The clean-up forced the closure of the highway for more than six hours between Uralla and Bendemeer with traffic diverted via Walcha.

Contra-flow conditions were put in place about 8am by the RMS to allow traffic to pass the scene.

The EPA was also called to examine the area and the oil spill.

It’s believed a build up in the exhaust sparked the blaze.