What can I do with my old propane tanks for the barbecue grill? Will the Town's rubbish removal contractor take them?

NO!

The Propane cylinders still have product in them and should be disposed of properly. If you wish to dispose of a propane cylinder you must first insure that it is empty, then remove the control valve and rinse the tank with water. Once this is complete, you may bring the cylinder to the transfer station on Beaver Street.