Reuters: Lawmakers grilled Interior Secretary Ken Salazar on Wednesday about his department’s six-month ban on deepwater drilling, a decision they said may cost the already battered Gulf of Mexico region thousands of jobs. The Obama administration halted exploratory drilling at depths of more than 500 feet and instituted more stringent safety rules in response to the April explosion of the Deepwater Horizon drilling rig and subsequent oil spill. Lawmakers at a Senate Energy and Natural …