Salt Lake County commissioners agreed Thursday to decide whether Hercules Inc. should be allowed to build a $145 million expansion to manufacture Titan IV and Delta II rocket motors - a project company officials say will add 750 construction jobs and $10 billion to the local economy.

The hearing will begin at 8 a.m. June 6th in the Commission Chambers, 2001 S. State.Hercules officials appealed to the commission after the County Planning Commission rejected the plans. Planners said they were concerned about the safety of residents in nearby Magna, especially after an accidental explosion earlier this month at a rocket fuel plant in Henderson, Nev.

Jack DeMann, Hercules public affairs director, said the company will lose $42 million for every deadline it misses. DeMann said the company wanted to begin construction June 1.