I just recently became a foreman. My very first job was a relatively small "dirt" job. I've done plenty of underground, so I felt pretty confident. Although small in size, the client was a so. Cal POCO. I had absolutely no idea how particular they really are. I installed per specs... Sweeping fiberglass 90's... Special depth coverage.... Special spacing between conduits..... Special slurry mix (what a nightmare that was).... Special compaction rates etc etc. I passed every inspection by the city step by step. One month later I get a call from my superintendent telling me I failed the city's mandrel test and everything needs to be ripped up, redug and redone.... Finished concrete and all..... All because a city mandrel wouldnt go through a couple ul listed factory PVC 15? bends..... Luckily I still have a job! The Point is if your an inside wireman running work BEWARE of POCO work!