Wagga, I tried doing a search for you on the power plant and semi-trailers, but did not find what you were asking for, I'm sure you searched too.
I believe that the entire fuel assembly weighs well under a ton. Fuel rods spend several years inside of a reactor. That's a major part of the attraction of nuclear reactors -- not a lot of truckloads of fuel going in.
As for mile long coal trains: 1 ton of coal produces 6150 kWh of electrical energy, so a 1000 MW plant would use 163 tons of coal per hour (6.5 tractor trailer loads of 25 tons each). I'll let someone else convert that to mile long trains per day.
