I am currently working on a project for a state highway department to make drainage improvements at existing bridge locations. At one particular location there is a metal drain pipe coming through a concrete abutment backwall. The metal pipe has been cut flush with the face of the backwall and now spills water (possibly from a scupper or catch basin) onto the beam seat. I am attempting to attach piping to channel the water to the roadway below. I need to connect a "transistion" ductile iron pipe before transistioning again to PVC. Plans state that the existing metal pipe is W.I. (wrought iron?). Since the pipe is cut flush with the backwall, it limits the use of a transistion coupling. Is it possible to weld the ductile iron pipe to the wrought iron pipe? If so, what sort of information would need to be brought to the welder's attention?