The larger airports receive fuel mostly via pipeline. The Conoco Phillips refinery at Wood River, IL
is a major supplier to Lambert-St.Louis. One could safely assume the Citgo, Exxon-Mobil and BP
refineries in the Chicago area supply ORD
probably draws from several LA
area suppliers, however the Chevron refinery is just a few miles south. PHX
would rely on fuel via pipeline mostly from LA
with supplies via a line from El Paso as a secondary supply.
Hope this helps.