As James said cut the block to do a cut out (not me either unless that is absolutely what the home owner wanted), or do a trap out.
With that building I would not worry about the copper line running in the block. Take a ball peen hammer and using the round end pop a hole in the hollow core of the block for a new entrance. Now seal up the hole where the copper tube is with silicone and maybe a small piece of screen wire if the hole is so large that the silicon will not stay in place, but seal it closed. Put your trap out cone in place and your bait hive.
easy peasy.......we look forward to your pics or better yet video!!
I thought about a trap out cone, but I have no access to brood yet, still a little chilly here for pulling a frame. Would the bees follow the pipe back into the cone and hive?
That's why I wanted to go the Hogan method, get some nurse bees out also. A cone would just collect the forages and drones. There are dozens of drones flying around also.
The pipe is in use, but the owner said she could reroute it, to give access to the hole.
The pipe does go into the cellar where bees are finding their way into. But no colony there, just a bunch of lost bees.
They're building in the block, no access to the walls as the footer is pretty solid.
Once satisfied with the population from the trap-out, pull this nuc and reconfigure the set up so the bees enter and exit through a box (Hogan method) without a cone.
Give it a couple weeks to allow the purchased queen to start laying and the bees to start filling the comb in the new pass-through box. Then add a trap out cone to the inside of the box and frame of foreign brood from the first box of workers you trapped.
You'd get two hives out of this for your time, two boxes and the price of a queen. Plus pick up a bit of cash for the removal!