Associate Press: Six days before the Deepwater Horizon oil rig exploded in the Gulf of Mexico, a BP drilling engineer called the rig a “nightmare well” that had caused the company problems in the past. The comment by BP engineer Brian Morel came in an e-mail April 14. On April 20, the Deepwater Horizon rig explosion killed 11 people and sent tens of millions of gallons of oil into the Gulf in the nation’s worst environmental disaster. The e-mail was among dozens of internal documents released …