I need to do some plumbing repair on the underground piping and of course its buried under concrete. My big question is are there any tips and tricks on how to fix it? The leaking seam is at a 45 degree elbow in the plumbing. My best guess is cut back 10' or so of concrete to give me some flexibility when installing the new elbow. Oh and best part - the actual pipe is covered with a mortar and when I was chipping it away I put the bit through another 45 so I now have 2 to fix..... lucky me.