After he had studied all the possibilities, General Groves explains in Now It Can Be Told: The Story of the Manhattan Project, he concluded that only one firm was capable of handling all three phases of the plutonium effort, and that firm was du Pont:
When I broached the subject to Arthur Compton, he agreed at once, saying that he knew Stone and Webster were overburdened and were way out of their field of experience, and that it would be a great relief to have du Pont in the picture. However, he warned me that we would encounter opposition, some of it quite strong and quite influential, from some of the people in his laboratory.
He told me that in the previous June he had assembled his staff and proposed bringing in an industrial firm to take over responsibility for the production phase of the plutonium project. The suggestion had resulted in a near rebellion, particularly among those whose entire experience had been in academic institutions. They simply did not comprehend the immensity of the engineering, construction and operating problems that had to be overcome. Whenever attempts were made to explain them, they brushed them aside as inconsequential. After the furor had subsided, Compton announced that he expected to go ahead with his idea.
He said that while his position had been accepted then, he had no doubt that there would be many objections, voiced and unvoiced, and that the selection of du Pont — the very symbol of large industry — would be particularly opposed. He went on to assure me that personally he was very much in favor of my proposal and, moreover, that he felt that du Pont was by far the best choice that could be made.
On the other hand, a number of his scientific people, particularly those who had been trained in Europe, where scientific and engineering education were more closely linked than in this country, had the idea that all design and engineering for the project should be accomplished under their personal direction. Some even went so far as to say that they could also supervise the construction.
When I visited the laboratory on October 5 and again on October 15, I was told by several different persons that if I would provide them with from fifty to one hundred junior engineers and draftsmen, they would then themselves design and construct the plutonium plant, rapidly and without delay. They added that the plant could then be turned over to a private company for operation, or possibly be run under the Civil Service.
The absurdity of such a proposal is apparent when it is remembered that this was the plant where our construction forces reached a peak of forty-five thousand and was so difficult an undertaking as to strain even the great resources of du Pont, with the full power of, and considerable aid from, the government and much of America’s industry behind it.
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The urgency of the project did not allow time for us to conduct any detailed security checks in advance of negotiations; instead, we relied upon the discretion and patriotism of American industry. We considered this a good risk and we were never disappointed.
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I said that there were three basic military considerations involved in our work. First, the Axis Powers could very easily soon be in a position to produce either plutonium or U-235, or both. There was no evidence to indicate that they were not striving to do so; therefore we had to assume that they were. To have concluded otherwise would have been foolhardy. Second, there was no known defense against the military use of nuclear weapons except the fear of their counter-employment. Third, if we were successful in time, we would shorten the war and thus save tens of thousands of American casualties. (I have always believed it was for these reasons, and particularly the last, that Carpenter and his colleagues on the du Pont Executive Committee agreed to undertake the work in spite of all the hazards it entailed for their company.)
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They pointed out that even in one of their own fields of specialization they would not attempt to design a large-scale plant without the necessary data that could be accumulated only by a long period of laboratory research, followed by semi-works operation: for example, it had taken them many years to get nylon into mass production; yet the nylon process was simple compared to what we were asking of them.
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I should make it clear that reactor theory at this time did not overlook the possibility that once a chain reaction was started, it could, under some conditions, get out of control and increase progressively to the point where the reactor would explode. If highly radioactive materials were blown into the atmosphere and spread by winds over a wide area, the results could be catastrophic. We knew, too, that in the separation of the plutonium we might release into the atmosphere radioactive and other highly toxic fumes which would constitute a distinct hazard for operating personnel. It was not surprising, therefore, that du Pont should entertain grave doubts about the desirability of joining us in our work.
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As the directors entered the room at their next Board meeting, they were asked not to look at the faced-down papers on the table in front of them. Carpenter explained that the Executive Committee was recommending that du Pont accept a contract from the government for a project in a previously unexplored field so large and so difficult that it would strain the capacity of the company to the utmost. He added that there were elements of hazard in it that under certain conditions could very well seriously damage if not well-nigh destroy du Pont. He said that the highest officials in the government, as well as those who knew the most about it, considered it to be of the highest military importance. Even its purpose was held in extreme secrecy, although if any Board member wished to he was free to read the faced-down papers before voting. Not a single man, and they were all heavy stockholders, turned them over before voting approval — or afterwards — a true display of real patriotism.