Elsie Mae Freeman was a laboratory assistant in the Chemistry Division of the University of Chicago's Metallurgical Laboratory ("Met Lab") during the Manhattan Project.
Freeman was in the Nonacademic Service Group led by Kathleen Florin. The Nonacademic Service Group was made up of laboratory assistants, technicians and secretaries. This group included Minnie Daniels, Aquilla Parsons, and Lillie May Porter among many other women.
For more information about women in the Manhattan Project, please see the following reference: