In February 1945, the end of war in the European theatre of operations was still a few months off in the future. Nonetheless, Allied leaders felt that the war’s end was close enough that they could begin to anticipate the post-war era. To that end, Churchill, Roosevelt, and Stalin met in Yalta—a city on the Crimean peninsula overlooking the Black Sea—on February 4-11 to discuss the shape of post-war Europe. Because of the tense relations between the United States and Britain on one hand and the Soviet Union on the other, which were reinforced during the meetings, the Yalta Conference is the oft-cited start of the Cold War.
In our “Countdown to the Cold War: October 1944” post, we detailed the struggles associated with the Hanford nuclear reactors, then known as atomic piles. In the last months of 1944 and in January 1945, engineers and scientists working on Hanford’s problems ironed out the kinks of the plutonium production process. Sometime between February 2th and 7th—sources vary on the exact date—the first weapons grade plutonium began making its way from Hanford to Los Alamos.
In the book, Hanford and the Bomb: An Oral History of World War II, author S. L. Sanger has this to say about the event:
[T]he first Hanford-produced plutonium was handed over by Du Pont to the Army. The next morning, Col. F.T. Matthias took it to Portland by car with a military intelligence escort. From there, Matthias and an agent went by train to Los Angeles where the package was given to an officer from Los Alamos. Matthias described the container as a wooden box wrapped in brown paper about 14 inches on a side and 18 inches high. It had a carrying handle and the syrupy plutonium, weighing about 100 grams, was carried in a flask suspended between shock absorbers.
The next time you’re about to board an airplane and TSA agents in the security area shout reminders of the restriction to 3-ounce containers of liquids and gels, think about how times have changed. During World War II, one of the most hazardous substances ever present on the face of the earth was carried on a regular passenger train. In a wooden box. Wrapped in brown paper.
Sanger’s book describes the meeting between Matthias and the officer from Los Alamos in what was almost certainly Los Angeles’s Union Passenger Terminal. Apparently, Matthias discovered that the officer was traveling back to Los Alamos in an upper berth, a means of rail travel that had privacy by means of curtains, but no real security, not even a door. Matthias discovered that the officer didn’t know what exactly he was being entrusted to carry back to Los Alamos. Matthias told the officer that it cost $350 million to produce the item and suggested to the man that he get a compartment with a locking door. The man did as Matthias instructed.
As revealed in to Critical Assembly by Lillian Hoddesson, et al., the Los Alamos contingent was very pessimistic about the quality and amount of the plutonium that they expected to receive from Hanford: “Oppenheimer was not optimistic about the ease of interacting with Hanford.” Ultimately, the quality and quantity of the Hanford plutonium was deemed sufficient to carry out the metallurgical research necessary so that plutonium could be used in the Fat Man weapon.
While the arrival of the Hanford plutonium in February 1945 was a huge event in the run-up to the Trinity test of a Fat Man type of atomic weapon, other activities related to Fat Man were taking place at Los Alamos at the time as well.
In December 1944, several new advisory boards and standing committees were created at Los Alamos. Chaired by physicist Samuel K. Allison, the Technical and Scheduling Conference was responsible for oversight and coordination of the transition from research to implementation. On Saturday, February 17, the Technical and Scheduling Conference met for four hours to discuss competing designs for the Fat Man-type weapon.
J. Robert Oppenheimer, the Manhattan Project’s director, argued throughout the day for simpler, more conservative design decisions. As Bruce Cameron Reed describes it in his excellent book The History and Science of the Manhattan Project, the final outcome of that committee meeting wouldn’t be decided until an end-of-the-month visit by General Leslie Groves:
On February 28, just eleven days after the TSC meeting, Oppenheimer and Groves decided provisionally on the Christy-core design with explosive lenses made of Comp B and Baratol. Characteristic of so many decisions in the Manhattan Project, their choice was a gamble: few implosion lenses had by then been tested[…].
With this end-of-February meeting between Groves and Oppenheimer, the design for the Trinity test was effectively fixed, and the lab could then focus on fashioning the numerous technologies into the world’s first atomi