Dayton Project

In 1943, the Manhattan Engineer District (MED) began the Dayton Project to investigate the chemistry and metallurgy of polonium. Because Monsanto Chemical Company was already working with polonium, it was chosen as contractor for the project.
In 1943, the MED-contracted work was performed at Monsanto’s Nicholas Road location (Unit I). As the project expanded, it moved into an old building belonging to the Dayton school district at 1601 West First Street, and by October 1944 all operations had been transferred to this location from Unit I. This site became known as Unit III. In early 1944 it became apparent that the space at Unit III was also inadequate, so the U.S. Army Corps of Engineers used a judicial proceeding to obtain ownership of a building known as the former Runnymeade Playhouse in Oakwood and turned it over to Monsanto for its use on the Dayton Project. Monsanto operated a laboratory at this second location and referred to it as Unit IV. Floors 4, 5 and 6 of the Warehouse at 601 East Third Street, Dayton, Ohio, were also utilized as part of project. When project needs again increased beyond the combined capacity of Units III and IV, preparations were made to move the entire operation to the present-day Mound facility in Miamisburg, Ohio. Processing began at Mound in February 1949. By the end of 1950, after either decontamination or demolition, the AEC released its ownership interest in the properties back to the original owners.
Throughout the time period for this facility from 1943 through 1950, the potential for beryllium exposure existed at this site.

Alternative Names

• Runnymeade Playhouse
• Dayton Board of Education building
• Old Schoolhouse
• Warehouse (floors 4, 5, 6)
• Unit 1
• Unit 3
• Unit 4

Type of Facility

• Department of Energy

Covered by EEOICPA

• Part B and Part E

EEOICPA Covered Years

• July 14, 1943-1950

Contractors

• 1943-1950 Monsanto Chemical Company
• 1950 (R. G. Mattern

Contract Numbers

• AC24-88DP43495
• AT-33-1-GEN-53-3
• AT-33-1-GEN-53, Modifications 2, 3
• W-35-058-ENG-71
• AC04-78AL04227
• AC04-76DP00053
• AC01-79CS20175

Document Identifier Prefix

• M-

DOE

• Comprehensive Epidemiologic Data Resource Analytic Data File Sets-Mortality Among Mound Workers Exposed to Polonium-210 and Other Sources of Radiation, 1944–1979
• Comprehensive Epidemiologic Data Resource Analytic Data File Sets-Cohort Mortality Study of Workers at Mound Plant, 1991
• DOE Facility List by Name
• FUSRAP Considered Site

DOL

• Tracking your DOL Claim Status
• Advisory Board on Toxic Substances and Worker Health
• Ombudsman’s Office
• Resource Center
• DOL Case and Claim Statistics
• Previous DOL Case and Claim Statistics-when covered as AWE facility
• Site Exposure Matrix

NIOSH

• FAQs About Your Case
• Advisory Board on Radiation and Worker Health
• AWE Site Wide Documents
• NIOSH Case Statistics
• Special Exposure Cohort Status Table
  • Petition 049: “Atomic Weapons Employer (AWE) employees who were monitored or should have been monitored for exposure to ionizing radiation while working at Monsanto Chemical Company Units I, III, or IV in Dayton, Ohio for a number of work days aggregating at least 250 work days during the period from January 1, 1943, through December 31, 1949, or in combination with work days within the parameters established for one or more other classes of employees in the Special Exposure Cohort.”

Other Resources

• Atomic Heritage Foundation
• Waste Lands-America’s Forgotten Nuclear Legacy Database