Asking the management of an oil refinery to explain sudden developments that reduce output is like sitting down to a poker game without enough cash to get you through. They can simply wait you out.

This past weekend the nation's largest refinery, the 600,000 bpd complex in Motiva Port Arthur, TX owned by Shell and Saudi Aramco; sustained a fire. Cory Wilchek of the Oil Price Information Service (OPIS)reported that a Shell spokeswoman confirmed there was an operational issue, and Motiva "initiated a safe and orderly shutdown of one of its units," but did not reveal the specific unit. (Why show your cards before you have to?)

Wilchek reported that the fire may have taken place in the hydrocracker unit, and with that unit, a crude unit and a reformer are all said to be offline. The fire reportedly took place in the newer portion of the plant.

How severe was the damage? While the Shell representative didn't reveal which units would be affected, she said that while repairs to the effected unit were underway, "operating rates on
the other units on site will be adjusted to optimize the overall site."

Market watchers said the units affected could be down for three to six weeks, which could affect distillate exports to Latin and Central America.

There was no filing with the Texas Commission on Environmental Quality (TCEQ) from Motiva.

Will the fire significantly reduce Motiva's gasoline production? That's where the transparency is needed. But it's not likely to change any time soon.