The article was quite clear that the PUC inspectors, like the FRA inspector who hardly has time to look at much in CA, are not doing detailed engineering inspections. The railroads are supposed to do that, and the large ones, at least, do. They are essentially "oversight" - trying to make sure that the RRs are doing the job right. Call it an insurance policy. I suspect that PUC was supposed to be doing this all along, but never put a priority on it. The "oil trains oh noes!" thing changed that, but they had to get money - so now they apparently have funding for 2 bodies. As has been said in a slightly different context: "Trust, but verify."

That said, if PUC doesn't even know yet where all the bridges are (or, for that matter, what a "bridge" is - that can be an issue at Caltrans too where the line between small bridges and large culverts can be fuzzy at times) they will have a hard time being even slightly effective for a while.