Melting the plates down is a novel idea. The problem I always run into when I make a transaction where destruction is required is that the customer wants proof of destruction. I recently purchased material from a Silicon Valley manufacturer that required proof of destruction, and specified shredding specifically, and then wanted a sample of the material after shredding to insure the shred was their material. If you incinerate there is no way to tell what the incinerated material is, I think this is why this method isn't used by customers requiring proof of destruction.
Some government agencies shred their own material, and you can purchase it off the government auction sites already destroyed, and some require the customer to destroy it, and provide proof, still others require a government official to represent the destruction so they have an eye witness.
It's a crazy world we live in, nobody trusts anyone anymore, so sometimes you have to jump through hoops to get an otherwise very simple task done, just to insure you are keeping with the owners requirements.
Scott
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