"[...] degauss and shred the platters and dispose of them in multiple locations."
For (some?) metal platters you can quickly reduce them to a shapeless lump by applying the flame of a standard plumber's gas blowtorch. Haven't tried that with vitreous platters.
When taking the drive to pieces you need a screwdriver set that covers small Torx screws and other "security" types.
Have had to do that incineration a few times when a drive had died and couldn't be erased. It also sidesteps the problem of there being data on any "hidden" damaged tracks that are no longer visible to the PC.
Biting the hand that feeds IT
