1) to remove the volume automation, the quickest way (for me) is to open the automation event list (available only via key command). Select any one volume event you see in there, use the "select similar events' function, and hit delete. Then close the list. If you have those key commands already established, the whole operation takes (literally) one second.
2) to prevent volume automation from being written, open the automation preferences and de-select Volume.
MacPro 8 Core 2.4 Xeon | 32G RAM | OSX 10.6.8 | Logic 9.1.7 | RME FF800 | 3 monitors | Toys for days