The Society for the Preservation of Canada’s Nuclear Heritage Inc. welcomes anecdotes about the nuclear industry and has reported a number of them in previous articles. This anecdote, authored by Geoff Hanna, was found as a hand-written note in a huge trove of material recently donated to the Society by Doug Milton. It concerns the extended irradiation in NRX in 1948 of a precious, small sample of americium (Am), a transuranic metal that was an extremely scarce material at that time. The sample came to Chalk River from the University of California, Berkeley. Geoff wrote:
My recollection is that Stan Thompson (of Berkeley) told Bernard Harvey (of Chalk River) to be sure to wipe off the capsule before it was put in NRX. He did, and got enough Am off it to suggest that the capsule had sprung a leak. However, he satisfied himself that it hadn’t – I don’t remember the details – and the capsule went into NRX. I think this must have been 1948.
After the irradiation – and very quickly to preserve short-lived species – the capsule was put in a shielding flask and Phil Aitkin and I took it to Berkeley, using an RCAF DC-3 out of Arnprior airport! Berkeley divided it up and we flew back, in the same plane, and with the same flask of course. This must have been in 1950. I don’t know what was done with our share.
Going back to 1948, Bernard measured the Am half-life using a quartz microbalance to weigh what he’d wiped off the capsule. We then irradiated it (some of it?) in NRX – perhaps there was more than one irradiation but we certainly had some 242Cm at least as early as February 1949. Altogether we got five publications out of the contamination and I lost a pair of pants to curium, a Canadian first, no doubt.
After he went to Berkeley, Bernard tried to pin Stan down on whether the capsule had been deliberately contaminated but he could not get a straight answer.
The Society continues to welcome anecdotes and documentation of all types as well as models or “souvenirs” garnered from experiments or instruments. To donate an item, contact the Society via info@nuclearheritage.com or call Jim Ungrin at 613-584-3055 or Michael Stephens at 613 584-9210.
