Y-12 Beta Chemistry Building 9206
Dad's Letter to Dr. Cruse
Among my father's papers was the following letter to Dr. John Cruse, M.D. dated 5 Nov 1979. It was written a few weeks after my mother's death in 17 Oct 1979.
See notes below regarding the last paragraph of the first page.
The last paragraph of the first page is particularly interesting in light of the 2006 "quiet conversation," to wit:
"In the period 1944-1947 Claudia was involved in the wartime processing of enriched uranium where the potential for ingestion was extreme by todays standards."
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The first sentence amounts to an admission that the work assigned to Claudia F. Osborn (Case), and her co-workers was extremely hazardous. The workers were intentionally kept uninformed as to the nature of their work for the purpose of maintaining project secrecy.
"In this case the 234U isotope (alpha emitter) was enriched to approximately 1 to 1.5% compared to a natural abundance of approximately 0.0058%."
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The second sentence points out the significant increase in the percentage of the 234U isotope present in the enriched uranium product of the Alpha Calutrons vs. the percentage of the same isotope present natural uranium. It assumes that the reader of the letter understands that the alpha radiation given off by the slow decay of the 234U isotope presents health hazards if ingested.
"The extent of ingestion is unknown but my own familiarity with the operation which involved calcination of UO3 there was airborne particulate dispersion sufficient to require frequent recovery from vertical surfaces for economic reasons."
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The third sentence points out that while the extent of ingestion by inhalation of 234U dust by the workers was never quantified, the amount of the dust in the workplace was so prevalent that recovery operations for the same were carried out in the UO3 calcining area of Building 9206.
"Body fluid and airborne monitoring for uranium was not a prime consideration under the pressure of the bomb development."
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The fourth sentence is an indirect admission that the pressure to produce sufficient enriched uranium for a bomb eclipsed concerns for worker safety.
"A list of other persons who have a similar employment history is enclosed. It could be of interest to follow the course of these individuals over the 30-year time span involved, if they could be traced. Some are still in Oak Ridge."
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The "list of other persons" referred to in the sixth sentence undoubtedly refers to the list of names set out in the "Memorandum to Dr. Riley."