Mississippi, with four other Gulf Coast states, has agreed to a reasonable and large settlement with BP, the petroleum giant, for damage inflicted when its Deepwater Horizon well broke and gushed 134 million gallons of crude oil into the Gulf of Mexico in 2010. The flow was unchecked for months, with the oil eventually spreading and damaging coastal and marine assets worth billions of dollars in the private and public sectors. The record $18.7 billion settlement Thursday was announced by Gov.