Alex, I'll leave the plumbing questions to the plumbers, but stay away from the concrete wall at least 24" to be safe. Your footings (not headers) probably extend from beyond the wall 6" or so, but depending on age of home, engineering, etc, could be much more. You may want to leave this to a pro, you could damage your foundation and cause huge problems with water infiltration into your basement if you don't know what you're doing. Have you though about how you'll get through the slab? BTW, cement is glue. The hard gray stuff is concrete.