Additional pressure is also required to move the oil. At lower levels, it becomes more expensive for companies to get the remaining crude out of the tanks. Roofs of storage tanks also float on the ...

In the big crude oil leak, Citgo crews began emptying Tank 41 on Sept. 27, 2018, after they spotted its floating roof listing to one side. On the morning of Sept. 28, 2018, however, the floating ...