MARLBOROUGH, Mass. – For the first time in 91 years, St. Mary’s Credit Union is branching out of Marlborough. The $441 million credit union has recently purchased a 3,600 square-foot building in Northborough. The facility will be renovated as a full service branch featuring six teller stations and two drive-up lanes and a drive-through ATM. The Northborough branch is slated to be completed by early spring 2005.