There are 2 Departments of Aging in Luzerne County, Pennsylvania, serving a population of 318,222 people in an area of 891 square miles.There is 1 Department of Aging per 159,111 people, and 1 Department of Aging per 445 square miles.. In Pennsylvania, Luzerne County is ranked 15th of 67 counties in Departments of Aging per capita, and 8th of 67 counties in Departments of Aging per …