A few weeks ago I saw a picture of a diesel beïng fueled on the road. I think that is a great idea for a diorama. Just made a setup ( no details, just the scene). Paul
At Delores Yard in Los Angeles, this type of refueling was done at the yard diesel facility by 18 wheelers. Lots of engines and lots of trucks. Now, I think UP has installed a small tank farm.
In California having a below ground fuel tank is a bit of a problem for the pollution laws. Much paperwork and testing at subtantial costs. I don't think the government actually knew SP was fueling directly from trucks. The Dolores facility is about a stones throw from several large refineries, so the feds and environmentalists had larger prey to complain about.