As I read the story, the actual violation is that the welders CARRIED ANOTHER WELD METAL with them along with the actual filler to be use in the weld. This falls under the category of an adminstrative non-conformance; it's not as if any pressure vessel welds are about to fail.
They do NDT these welds, you know.
That used to be my bread and butter. Of course if the metal aint right the x-rays and other tests can still look good. And a Telley/Brinell hardness test my not be legal. I hear that now days they have NDT ways of testing the metalurgy.
I've just been reading and re-reading the stories available on this issue and it's tough to tell exactly what we have (writers have a terrible time with accurately reporting anything technical!) but.... there appear to have been "faulty" welds actually found... so we've got more than "just" the administrative non-conformance because there are real welds with something found wrong with them. What I can't tell is whether the "faulty" welds had the wrong filler material in them or if it was something else completely unrelated to the issue of carrying multiple filler materials with them at once.
From my own experience (former pipefitter, pipe welder and certified inspector once upon a time) I can only say that it was incredibly stupid to have EVER allowed any filler material to be checked out other than the material needed for the specific work at hand. Just setting yourself up for this situation and as soon as the first weldor violates their integrity and training the entire program is called into question on an issue very difficult to determine the scope for.
Could be very expensive and time consuming depending on the details...