Aerial Spraying

Perhaps slightly off topic......
While working on Camden Road, Blessington yesterday (17/11/07 7.30am - 10.30am), a helicopter came over a hill and started spraying a plantation about 4-500 meters from where we were working.

The wind was blowing in our direction (coming from the north-east), and we could smell the chemicals being used to spray the plantation.
One worker stated that he could "taste it in the back of his throat".

What I am wondering is:
Is there some regulation that requires notification, or roadside signage of aerial spraying occurring in an area that is likely to be frequented by members of the public?

The North Esk river would have had to have some overspray reach it, as it was between the helicopter and some of our work crew.

There was certainly no signage on Camden road.

At the conclusion of spraying, 3 vehicles drove out of Camden road....one had "Helicopter aerial spraying" sign written on the side.
The second was a Gunns truck with tanks on the back, and the third was a red Hilux ute.
The occupants of the ute stated that they were spraying herbicide, when stopped by one of our workers.