Transocean, LTD, the owner of the Deepwater Horizon drilling rig that exploded last spring, killing 11 workers and unleashing the worst offshore oil spill in U.S. history, has awarded its top executives big bonuses for making 2010 the “best year” ever for safety. After disclosing the bonuses, Transocean, which leased the rig to BP and helped supervise the drilling, acknowledged that the reference to its best safety year might appear “insensitive” to some.