Situation: Leak shows up in a dirt area surrounded by concrete next to a junior high school's varsity baseball dugout. The area is dirt because prior to eight years ago there were manual valves in the concrete that controlled two zones between the field and the street. We took the manual valves out, used one lateral line (going under concrete in different direction from leak area) as our main line extension and used the other one as a wire chase to set automatic valves in the grass area. This is the third time the leak has shown up in the past three years. Every time we go out and dig under the wall the leak dries up. Area is supplied by an old galvanized QC line that we can't find. Only thing I can think of is that there is a small leak in a line that used to supply a drinking fountain that has been capped/abandoned. The concrete in the dugout's porch will need to be removed so we can see what the heck is going on.