In Australia:
FUEL DUMPING IN FLIGHT
CAR 150(2)(d) regulates the dropping of anything, including fuel, from an aircraft in flight. Additionally, Air Navigation (Fuel Spillage) Regulations prescribe penalties for the unauthorised release of fuel from an aircraft for other than in an emergency.
When fuel dumping is required, the pilot in command should request authority from ATC before commencing a fuel dump, and must:[list=a][*]notify ATC immediately after an emergency fuel dump;[*]take reasonable precautions to ensure the safety of persons or property in the air and on the ground; and[*]where possible, conduct a controlled dump in clear air above 6000 ft and in an area nominated by ATC[/list=a]
Dumping in a holding pattern is a little silly.