BP's Cement Plug Is Successful, Spill Costs Reach $6.1 Billion 1.11K Jeff Neumann 08/09/10 05:29AM Filed to: oil spill oil spill Bp Deepwater horizon Disasters Gulf Of Mexico Yesterday BP announced that the cement plug in the leaking Gulf oil well was a success, and that a relief well would be finished later this month. The company also said the spill has so far cost it $6.1 billion.