Here's why:
http://www.ft.com/intl/cms/s/0/256f583c-7a83-11e1-8ae6-00144feab49a.html#axzz1refG2zkA
...Half the refining capacity on the populous US east coast is set to disappear. Sunoco has pulled the plug on two refineries already and warns that another in Philadelphia will close in July if no buyer steps forward. ConocoPhillips is trying to sell a refinery in Pennsylvania, idle since last year. On May 1, it will spin off its refining business. More than 3m barrels of daily refinery capacity have closed in western countries, since the financial crisis, says the International Energy Agency, the westââ¬â¢s oil watchdog.
http://www.ft.com/intl/cms/s/0/256f583c-7a83-11e1-8ae6-00144feab49a.html#axzz1refG2zkA