Well, good news. I found the leak. I did exactly what Kiril and 1idejim recommended, and blocked all 25 (low volume) emitters in zone one, and did a walk through after turning the zone on. But the mystery continues. Initially the entire zone was bone dry, so I went back to the source, the PVB. And water was bubbling out of the ground about 2 feet from the PVB. The reason I missed it before, is that the PVB was pulsating large amounts of water and covering the area where the leak was. The PVB is not pulsing water now, even after several minutes. The 'Mystery' as I see it, is that the leak is long before the zone one valve. And the remaining nine zones still operate normally, with absolutely no water at all leaking out of area I found severely leaking when zone one is on. Could be that only zone one builds up enough pressure to separate a crack in the PVC underground. Give me a few days to repair the leak and recheck everything, and I'll let everyone know what I found and if everything is back to normal. Thank you so much for your help.
Last edited by Pete215; 12-16-2013 at 10:28 AM.