the only problem you will run in to is keeping every thing at the same potential, your GFCI will function your just in a situation where that circuit may or may not open in the event the motor becomes energized, you might be able to go out there and take that hot wire and touch it to the well motor and weld with it! lol. it will be cool to know the results!Again, great thoughts. It’s nice to be able to bounce this off of some intelligent sources. The more I think about it and read the replies above, I think that indeed a two pole GFCI would work. Looks like the next step is to install one and see if we can create a test.