Specialist HAZMAT crews are on scene at a diesel spill in Kembla Grange outside Bunnings Warehouse.
A trailer carrying 800 litres of diesel overturned at the roundabout on Northcliffe Drive around 3pm, with diesel spilling across the road.
"HAZMAT crews from Shellharbour are having a good look, but it appears it hasn't entered the waterway," Fire and Rescue NSW Duty Commander Greg Purvis said.
"Booms are in place to stop it entering the drains and creek."
Duty Commander Purvis said at this stage there is no sign or any diesel in the creek.
Westbound traffic on Northcliffe Drive, between the M1 Princes Motorway and Princes Highway, is very heavy.
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