Illegal dumpers were busted by a vigilant civilian who recorded the incident on his dash cam on Saturday.
The Kings Park man was driving along Peter Brock Drive, Eastern Creek about 11.05am, when he noticed a plume of dust ahead.
When he got closer, it’s alleged he saw a tip truck with its hoist up driving away from a pile of building waste dumped on the side of the road.
The man called police to pass on his recording.
Blacktown police and the Environmental Protection Authority have reviewed the footage.
The company has been identified and investigations continue.