in laboratory testing of samples that heating to retired the graphite by 24 percent, to by 45 percent and to by 94 percent, but the consequences of heating the reactors so much had to be considered before this was attempted. The other problem was that the bismuth phosphate process used to separate the plutonium left the uranium in an unrecoverable state. The Metallurgical Laboratory had researched a promising new redox separation process, using hexone as a solvent. The AEC was concerned about the supply of uranium, and the General Advisory Committee of the AEC recommended that construction of a redox plant be given top priority. Meanwhile, the waste-settling tanks filled up with sludge, and attempts to transport it to the waste storage (241) areas were unsuccessful. It was therefore decided to bypass the waste settling tanks and send sludge directly to the 200 area, and construction of a bypass commenced in August 1946. GE invited bids for the construction of a new waste storage tank farm. Efforts were made to make better use of the available uranium. Turnings, cuttings and shavings from the slug manufacture process had been sent to the Ames Laboratory in Iowa for briquetting. The equipment there was shipped to the Hanford Engineer Works. The briquettes, along with uranium scrap metal, was sent to the Metal Hydrides Company for recasting into billets. During 1947, tensions with the Soviet Union escalated as the Cold War set in. Clarke was succeeded by Carleton Shugg on September 2. Within days of arrival he demanded overtime be used to speed up construction work then in progress. The size of the nuclear stockpile was limited by plutonium production. There was enough for thirteen bombs at the end of 1947. Walter J. Williams, the AEC's director of production, worked with GE engineers to produce plans for three replacement reactors (called BR, DR and FR). To save time and money, they would be built adjacent to the existing reactors, where they would be able to use their cooling water and separation facilities. Two more reactors would then be built on new sites. While this was being considered by the AEC, GE experimented with annealing, and found that if the reactors were run at and then slowly cooled, the graphite's crystalline structure could be restored. The reactors could be run at higher temperatures by increasing the power level. Some helium in the atmosphere surrounding the