How to fix a leak in the wall
I'm removing an old shower stall from a back room in our house that used to be a small self-contained area for visitors. I believe the room actually used to be a kind of sitting room/bathroom facility for the nearby pool and then got closed off. Whatever the history, we've decided to remove shower, toilet and plumbing and turn the area into an office, complete with bookshelves, built-in desk, etc.
So today I commenced with trying to remove the plumbing, and ran into immediate problems. One of the copper pipes for the former shower comes up straight from the concrete floor, but the other pipe (I believe the hot water) comes out from the bottom angle where the wall and floor meet. I don't know what would have possessed anyone to do it this way, but it's been an absolute nightmare to deal with. If it had been straight out of the wall, or the floor, it's not that difficult an issue to deal with, but being directly in the angle makes it very hard to try and chisel around, because I'm trying to work at both concrete floor and block. The worst case scenario that I was trying to avoid was causing any pinhole leaks in the copper through the constant jarring of the nearby chisel, yet that is exactly what's happened, and annoyingly the leak is an inch or so in the wall.
So I'm now left wondering how to deal with the problem. Initially I had been hoping to work a big enough hole that I could use a small pipe cutter to cut the pipe back in such a way that I could use a Sharkbite cap to seal it off and still have the end sitting deep enough that I could comfortably drywall over the hole. Now of course I have to open up the hole enough that I can cut the pipe far enough back to reach the pinhole leak. I have no way of knowing whether this pipe is coming up from the concrete slab underneath the block wall, or was fed down from above via the wall cavity. If the latter I might be able to pull out enough slack to help cut the pipe where necessary. If it's coming up out of the slab I think I'm going to have to take out substantially more of both the block and the slab around the pipe.
Any suggestions from the plumbing fraternity on how they'd go about this? I'm thinking of hiring an 11lb jackhammer for the job. I figure on having to take out about a third of the block around the pipe jutting out from the wall, which should be small enough not to destabilize the wall. Once done I'll use hydraulic cement to seal it all up again.