When you say "Do I need to ground anything?" what are you asking specifically?

Do you need to ground the pump? -- (Revised - see answer below)
Do you need to ground the plumbing stubs? -- No

If you had metal plumbing it would be required to be bonded and grounded.

This post was edited by jakethewonderdog on Thu, Jun 12, 14 at 10:52

The wiring from the panel to the pump should include a grounding conductor. And if the well casing is metal, it should be grounded to the premises electrical system.

bus_driver and wreck:

If this is a typical older 2 wire pump, they didn't include a ground wire in the drop to the pump. If it's newer they would have included a ground wire.

I was assuming this was an older pump - and so the question would be, "Do I have to pull this pump and rewire?" My initial answer was "no" ( you would fix the ground when you replaced the pump).

I'm re-thinking that answer.

If the pump isn't grounded and you have changed the plumbing to PEX it is probably advisable to ground the pump and casing now rather than when you pull the pump for a replacement.