Burning metal and IT equipment (incl old Paint Booth) is not an environmental solution that I can approve.
We are talking about electric cables, toxic materials in computers, galvanized ductwork with paint residue, electric motors and other potential hazards. I will not permit any on-site burning like this.
No problem if any authority needs to attend to witness the items segregated for disposal, take photos etc, but it should be on the basis of us dispatching it off-site by an approved scrap merchant.
I have not seen confirmation from you that the items in question can be disposed of from an accounting (not statutory) standpoint.