ST. PAUL — Rochester residents would be allowed to serve on the authority board overseeing Mayo Clinic's Destination Medical Center plan under a Senate plan unveiled Monday. It's a sharp contrast to the previous proposal, which would have prohibited any Rochester residents from serving on the authority. That group will decide how to spend millions of dollars on public infrastructure. The Senate plan also requires Mayo Clinic to spend $250 million on construction before state dollars could be tapped for Mayo's 20-year expansion. That's $50 million more than in the House version of the plan.