The Unitarian Universalist Society of Bangor this month officially joined the ranks of the denomination’s Welcoming Congregations program. Many in the religious community of Greater Bangor assumed the church had joined the program designed to welcome and celebrate bisexual, gay, lesbian and transgendered worshippers years ago. The Unitarian Universalist Association, however, just granted the designation earlier this month. “As we see it, there are two compelling reasons to become a Welcoming Congregation,” Bill Carlin, chairman of the Welcoming Congregation Committee, wrote in the church bulletin. “First, we do it for our own sake. It is an expression of our faith, an affirmation of our principles. Secondly, we do it to proclaim our welcome to all who may be interested.” The 173-year-old Bangor society began the process more than a year ago, and over the past 15 months has conducted workshops and discussion groups at the Park Street church. At its annual meeting in May, the membership made its decision.