Thank you for your reply. I’ve been into the “attic” and I could not find a pipe coming from that area. I can only assume that the pipe goes down into the slab and back to wherever it’s source is. Any thoughts on the most likely starting place might be? Is there a way for me to trace it back or some tool I might be able to rent to help me trace it back? At this time my only obvious option appears to be to cut a hole into the exterior wall (plaster, chicken wire, etc) and hopefully find the leak and cap it. If I could afford it I would call a plumber because I know he or she would, most likely, take one look and say something like “oh yeah, I’ve seen this before. I can fix it in less than 2 hours. It’ll be about $350 dollars.” I’m sure the price would be fair but I don’t have it right now. I have some basic plumbing tools: torch, solder, threading tool, pipe cutter, spare caps, pipe and elbows I just need to know where to use them.
Thanks again for your advice, I appreciate it.