Umpqua Bank is deepening its Douglas County roots by building an employee training center in Roseburg.The "corporate campus" will combine several banking departments as well as provide training classrooms for the bank's 625 employees statewide.Umpqua Bank bought 1.5 acres for $627,000 from Pacific Housing Management LLC earlier this week. The site is next to Umqpua Bank's branch and support services building at 1790 N.W. Garden Valley Blvd.Bill Haden, president and chief executive officer of the Roseburg-based bank, said construction will begin this summer with completion planned for next spring."What this building is going to do is give us the space …