This could also be good news for US firms that are involved in South American finds, Devon Energy , the largest independent oil firm in the US, recently signed a long lease deal for the deep sea exploration vessel Deepwater Discovery from Transocean. Devon has had pre-salt production running in Brazil since 2007 on their Polvo field & have an additional 9 blocks that are waiting to be fully surveyed. One of these, the Wahoo prospect is currently drilling at approximately 18,600 feet. Devon & its partner partners plan to conduct additional evaluations of the well when it reaches its total targeted depth of approximately 20,000 feet.