They tried to cover up the evidence with lies,
They tried to cover up the evidence with lies, ads, videos, and Cortex. Cortex is a skin burning chemical banned in the U.K. which BP used as an oil dispersant. The cortex and oil would form little tar balls and sink into the ocean (hiding the evidence), and creating huge ugly clouds of oil underwater , killing entire reefs. Though BP denied the effects in a comment on YouTube, National Geographic has video evidence of it.