Southern Tier Environments for Living, Inc. - STEL | 112 followers on LinkedIn. Southern Tier Environments for Living (also known as STEL, Inc.) provides rehabilitative and support services to persons with mental illness and other disabilities in Allegany, Cattaraugus, Chautauqua, and southern Erie counties. Our service spectrum includes residential treatment group homes & apartments, supported housing, single room occupancy housing, vocational rehabilitation, case management, social supports.