I found the problem. It is PVC, but it's not pipe. I don't know how they got away with using a PVC hose 25 years ago, when the house was built, or how the flippin' hose lasted this long. I do have to replace the whole thing, with copper, whatever I can get to fit on the next junction, but it shouldn't take nearly as long as I originally thought it would, because it's only going to be about 6 ft. of pipe. I dug out the trench, and now I have fairly easy access to everything that I need to fix the damn thing. Does anyone know how hard it is to dig a trench that's 4 feet deep and two feet wide. I'm glad I gave up that dream of someday being a ditch digger, I tell you what. Okay, the digging has officially kicked my ass, and I'm going to bed now.