Electrical wire inside Schedule M copper tubing

I don't know what regulations allow, but I have never seen horizontal boring done without installing the HDPE flex conduit as part of the process.

They bore by pushing the bit forward until they hit the destination. Then they swap the boring bit for a pulling end, and pull the conduit back through the hole as they are removing the drill rod. There is no separate conduit installation from the boring; you can't realistically push conduit through the bored dirt afterward.

How are you planning on doing the boring? Is this something you are going to jerry-rig yourself, or hire a company to do? If you are hiring it out, they likely will have some leftover end spool. As you say, 30 feet is a small fraction of the 2000ft spool. It should not be hard to get that as leftovers from the boring company, I would think.

And if you are doing it yourself, perhaps you can still buy some end spool offcuts from a boring company.

1. Cut open the drywall. You can then use a piece of plywood to cover the hole so that it's easier to remove in the future.

2. Sounds like too much work. First step, make sure they are GFCI protected. If you don't know if they are GFCI protected, you can get a GFCI outlet tested from the hardware store. And while you're there, get outdoor box covers. Then you can just replace the face plates with the outdoor box covers. MUCH easier than removing the outlets.

3. You don't need conduit. Get an "old work" electrical box. Cut a hole BELOW your breaker panel. Run the wire from that hole straight up through a knock-out in the bottom of the breaker box. Then you can push the wire through the top of the "old work" electrical box and mount the box in the wall. See, no conduit needed!

Based on response to my first answer:

1. Hooray!

2. Turn off the breaker. Remove the outlets and install wire nuts on all of the wires. Install blank faces plates.

3. OK, you still don't need conduit. Just drill a hole through the top plate of the wall. You can then run the cable up the inside of the wall, through the hole, and then down to your breaker panel with all of the other wires.