ML19340C424
| ML19340C424 | |
| Person / Time | |
|---|---|
| Site: | 07000882 |
| Issue date: | 08/13/1980 |
| From: | Lorio P COLUMBIA UNIV., NEW YORK, NY |
| To: | Grier B NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I) |
| Shared Package | |
| ML19340C420 | List: |
| References | |
| NUDOCS 8011170278 | |
| Download: ML19340C424 (2) | |
Text
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O Columbia University in the City of New York l New York,N. Y.10027
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August 13, 1980 Mr. Boyce H. Grier Director Region I US NRC Office of Inspection and Enforcement 631 Park Avenue King of Prussia, PA 19406 Re:
Inspection 70882/78-01
Dear Mr. Grier:
In accordance with 10CFR70, Section 70.52 (a), and item 3 of my letter dated June 27, 1980, I respectfully submit the following details on the lost 58.4 grams U - 233 foils contained in 60 grams of uranium.
This source was last used in January of 1971 during an experiment at our 570MeV proton accelerator.
Since this was the last run of this machine prior to a major modification, which was anticipated to last for several years, we ran five separate experiments simultaneously.
At the termination of this run all the experimenters broka down their experiments and beam tube connections in order to clear the experi-maatal area for the upcoming major modification of the accelerator.
Althougn there was a great deal of activity (not radioactive) on the floor there didn't seem to be any confusion.
One experimenter was using the U -233 foils in a chamber. in order to study binary and tertiary fission events.
He also had a pair of sim-ilar dumy chambers for comparison.
During the process of packaging the equipment for return to the campus, it appears that the dumy enambers were packaged and returned instead of the chambers contain-irg the U - 233 foils.
Since U - 233 is primarily an alpha emitter, but also has some low-energy gamma rcys associated with its decay, there were no expected levels on the outside of the package. These chambers were returned to the campus and kept in the dead stroage.
Soon after that run the government ~ contract for this research was terminated and these chambers were kept in dead storage.
It was assumed for many years that the U - 233 foils were in these chambers, until a physical inspection by Mr.
J.. Joyner in la79, when the loss was discovered.
Immediately af ter this last experiment the cyclotron was dismantled.
During the dismantling all materials in the cyclotron building were 8011170MT
carefully surveyed and all materials that were radio >ctive, like chambers, structural materials, nuts, bolts, gaskets, etc., were
'placed in a large metal container ( the old vacuum chamber of the cyclotroa) and were sent to the West Valley burial site disposal.
A new chamber was then installed in the cyclotron.
The only remain-ing radioactivity at the Nevis Cyclotron Laboratory was the pole tips, coil tanks and some of the internal shielding blocks which were to be reused. Some reusable equipment like power supplies and pumps that had some induced activity were stored in the 200 meter experimental tunnel.
Several elaborate searches of both Ne'vis, Pupin and Engineering Terrace leads to the conclusion that these chambers were disposed to the West Valley burial site with the remnants of the machine.
This shipment was made by the Moore Flesher Transportation Company and paid for on Pay Order #3581 dated Novemer 1971.
If you have any questions regarding this matter, please. feel free to contact me.
Sincerely, f f Lrd Philip M Lorio Health Physics Officer cc: Howard A. Jacobson t
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