homerak, Just one question, "What happens when the foundations and building settles over time, which it will, can the gas and fuel oil lines support the building and equipment?" If the code doesn't take this into account, I would reject it. Good practice would be be to bring the lines up above grade just outside of the foundation line with an emergency block valve, run them into the building, then take them overhead as a header and provide valved line drops at point of use.
Remember, "Common sense and safe practice is the foundation and intent of all codes and standards."
Hope this helps.
saxon