 During the war, when Oak Ridge's Manhattan Project facilities were operating around the clock, the chapel building was also in use nearly 24 hours a day as a venue for worship services, weddings, and other occasions for local workers of various Protestant, Catholic, and Jewish religious backgrounds.At the peak of wartime activity in Oak Ridge, when the population exceeded 70,000, the United Church employed four ministers and conducted worship services in the Chapel on the Hill, East Village Chapel, and the Jefferson Theater, as well as Sunday school classes in several local schools and a trailer camp.By 1951, the United Church Chapel-on-the-Hill consolidated as a single interdenominational congregation, making its home in the Chapel on the Hill building.