Nuclear Museum Logo
Nuclear Museum Logo

National Museum of Nuclear Science & History

Walter J. Grundhauser

Research AssistantChicago, IL

Manhattan Project VeteranProject Worker/StaffScientist

Walter J. Grundhauser was a research assistant the University of Chicago’s Metallurgical Laboratory (“Met Lab”) during the Manhattan Project.

At the age of twenty-four, Grundhauser was recruited the join the Met Lab. At the time, he was a graduate fellow at St. Louis University School of Medicine. Although the information about the job was vague, the St. Louis Post-Dispatch reported that “Grundhauser had an inkling that the position had to do with radiation when he recognized one of the interviewers as the author of a paper on alpha particles.”

At the Met Lab, he worked in the Health Division. As a biophysicist, his focus was determining the short-term biological effects of full-body radiation and radioisotopes on mice, rats, and rabbits.

Grundhauser worked at the Met Lab from 1943 until 1945. In April of 1945, he was advised to take a month’s leave because he was suffering effects from being overexposed to radiation. 

Grundhauser told the Post-Dispatch that when signing onto the job, he and his colleagues were promised that the bomb would be only used for defense. Grundhauser made his position clear when he became one of seventy scientists to sign the Szilard Petition, a document written by physicist Leo Szilard petitioning President Truman to avoid using the atomic bombs on Japan.

Walter J. Grundhauser's Timeline
19431945 Worked at the Met Lab.

Related Profiles

William T. McNamara

Oak Ridge, TN

William Thomas McNamara worked in Oak Ridge Tennesee with his wife Mildred Wilton from 1942 to 1946. Prior to accepting a job at Oak Ridge, McNamara had worked at the Charlestown Navy Shipyard in Boston.

Wilmer C. Sadler

Los Alamos, NM

G. Robert Gunther-Mohr

Washington, DC

G. Robert Gunther-Mohr joined the Manhattan Project in 1944. Mohr worked on the top secret polonium trigger being developed for the plutonium bomb at the Monsanto Chemical Company in Dayton, Ohio.

J. P. Heater

B Reactor/100 Area

Heater worked at the 100-D Area at Hanford during the Manhattan Project.