Semi with LOOOOOOOONG tank on tralier

[Redbug]

If I had to guess...to me it looks like a commercial size propane tank.

 

[tawilson]

If I had to guess...to me it looks like a commercial size propane tank.

My guess is an underground fuel tank. If they use heavy oil they use hot water from the boiler to keep the fuel warm so it can be pumped to the boiler, therefore the pipe connections on it.