Easy Global Dumping Without Using Mining Towers

When you activate Dump Zone tool, a dialog window pops up with all currently available dump-able materials. You can then disable/enable each material as you see fit, and drag your dump area; only the currently selected materials will be dumped in that zone.
While the tool is active, small icons of the material(s), similar to Cities Skylines district policy icons, appear above each area you've assigned for dumping.
Too many times have I moved a mining tower's work area forgetting that I had trucks dumping 1 specific material in the previous area; then all of the sudden I've got waste and slag being dumped on my rock pile.