It is legal in many situations to scatter human ashes in Illinois. It is always permissible to scatter them on your own private land, however if you wish to scatter them on any type of public land, permission should be gained. It is also not legal to scatter the ashes anywhere near water sources, trails, and roads.
Only if you get permission. If not, it will not be legal.
Yes
You would need the permission of the owner of the property where you are doing so.
It is not legal to pour human remains into any body of water
No. Any ashes without permission is littering.
No, they didn't.
It is not legal to dispose of human remains anyplace. You are not going to be able to legally arrange to scatter your husband's ashes in the Seine.
The link below will give you advice as to where you may scatter cremains in California.
Scatter My Ashes at Bergdorf's - 2013 is rated/received certificates of: Canada:PG (Ontario) Japan:G Netherlands:AL UK:PG USA:PG-13
You are supposed to burn it and then scatter the ashes.
Pretty much anywhere you like, provided it is outdoors and on public property. Rivers and lakes are popular areas for the scattering of ashes.