Howdy all... I'm removing a wall to put in a sliding door to the deck, and I got such amazing help on a plumbing board relocating a water pipe, that I'm hoping you all can help with an electric issue. I'm encountering a couple problems with an electric outlet that is located in the section of wall I'm removing. It is a standard 2 plug-in receptacle.

(1) I've determined that each of the plug-ins in this outlet is fed by a separate circuit. I determined this by plugging lamps into each socket. When I turned of circuit 10 at the main box, one light went out, but the other remained lit. When I turned off circuit 12, the other light went out. Is this normal? What can be a cause for this?

(2) I had to remove some flooring to reroute boiler heating pipes, and in the process I located the electrical feed which seems very taught, indicating I do not have enough length to relocate the outlet to the side of the new door. Because that option seemed impractical, my original plan was to simply take apart the outlet, cap off the wires, put in a metal box and leave it under the floor. However, while buying the supplies at Home Depot, I've now been told this is out of compliance with code, as the box needs to remain "accessible." I just can't figure out any way to leave this box accessible with the current wiring length. Also, I'm guessing issue #1 above may make that plan impossible in the likely event there is something branching off one of the plug-ins.

Thanks in advance for any advice you can provide based on my layman description. Of course, I'll be happy to do any investigation needed to fill in additional facts.