An operation involving any of the following:
1) Deepening from one zone to another zone.
2) Completing well in an additional zone.
3) Plugging back from one zone to another zone.
4) Sidetracking to purposely change the location of the bottom of the well, but not including sidetracking for the sole purpose of bypassing obstructions in the borehole.
5) Conversion of a service well to an oil or gas well in a different zone.
6) Conversion of an oil or gas well to a service well in a different zone.