Nope, fuel tankers are lined up 24-7 at the refinery. It supplies gasoline/diesel fuel for stations ranging out 100 miles in every direction. It is a regional hub.
I'm constantly amazed when people prefer one brand of gas over another. It's all coming out of the same refinery, same storage tanks, and then delivered in generally unmarked fuel tankers.
Grondike transportation has a lot here with dozens of fuel tankers that run around the clock.
That's how this refinery makes record profits year after year... The Cushing pipeline from Odessa, currently pumping WTI is all coming into Ponca... So the refinery gets to set it's own price, (word is about $56 a barrel right now) and it will stay that way. You think gas in PC is expensive now??? Wait until the Keystone from the gulf is completed to Cushing... It'll go back up to offset the loss of profit margin here in PC.
And for the record, not all gas is the same. It's the additives pumped in while filling the trucks that varies the petrol... Shell arguably has the best additive package, but the Cph/Ph66 is a really close second.