Just spit-balling here, I'm assuming API 1104 would be the governing code for the pipeline, have you looked through it to see if there is any reference to a code or standard for the cadweld?
jwleger685,
I have used NACE SP0169 and there is a little bit about Thermite welding in ASME B31.4. Other than that, I would reach out to the client of the pipeline. I have done work for Trans Canada and I think they had some internal document we used when doing pipeline work for them.