Editing Calutron (section)

== Construction ==
[[File:HD.4A.145 (10406006195).jpg|thumb|alt=An array of industrial buildings with lots of power poles and wires, with a pair of smokestacks in the background|The Y-12 electromagnetic plant]]
Construction of the electromagnetic plant at Oak Ridge, codenamed [[Y-12 National Security Complex|Y-12]], commenced 18 February 1943. The facility would eventually comprise nine major process buildings and 200 other structures covering almost {{convert|80|acres}} of floor space. The {{convert|825|acre|adj=on}} site in Bear Creek Valley southwest of the Oak Ridge township was selected in the hope that the surrounding ridge lines might contain a major explosion or nuclear accident.{{sfn|Jones|1985|p=130}} Problems with the substratum required the excavation crews to perform more blasting and excavation to provide adequate foundations for the heavy machinery in the facilities.{{sfn|Jones|1985|p=134}}

Supplies and materials of all kinds poured in: 2,157 carloads of electrical equipment, 1,219 of heavy equipment, 5,389 of lumber, 1,407 of pipe and fittings, 1,188 of steel, 257 of valves, and 11 of welding electrodes. The racetracks required 85,000 [[vacuum tube]]s. Where possible, off-the-shelf components were used, but all too many components of the calutrons were unique.{{sfn|Jones|1985|p=132}} Two purchasing departments were established, one in Boston near Stone & Webster for facility equipment, and the other at Oak Ridge for construction supplies.{{sfn|Manhattan District|1947e|p=4.1}}

The Chief Engineer of the Manhattan District, [[Colonel (United States)|Colonel]] [[James C. Marshall]], and his deputy, [[Lieutenant colonel (United States)|Lieutenant Colonel]] [[Kenneth D. Nichols]], discovered that the electromagnetic isotope separation process would require {{convert|5000|ST|abbr=off}} of [[copper]], which was in desperately short supply. However, they realized that [[silver]] could be substituted, in an 11:10 ratio of copper:silver. On 3 August 1942, Nichols met with the [[United States Deputy Secretary of the Treasury|Under Secretary of the Treasury]], [[Daniel W. Bell]], and asked for the transfer of silver bullion from the [[West Point Bullion Depository]]. Nichols later recalled the conversation: {{blockquote|He explained the procedure for transferring the silver and asked, "How much do you need?" I replied, "Six thousand tons." 'How many [[troy ounce]]s is that?" he asked. In fact I did not know how to convert tons to troy ounces, and neither did he. A little impatient, I responded, "I don't know how many troy ounces we need but I know I need six thousand tons—that is a definite quantity. What difference does it make how we express the quantity?" He replied rather indignantly, "Young man, you may think of silver in tons, but the Treasury will always think of silver in troy ounces."{{sfn|Nichols|1987|p=42}} }}

Eventually, {{convert|14700|ST|t ozt|abbr=off}} of silver were used,<ref>{{cite news | title=The Silver Lining of the Calutrons | year=2002 | publisher=Oak Ridge National Lab | url=http://www.ornl.gov/info/ornlreview/rev25-34/chapter1sidebar6.htm | work=ORNL Review | access-date=22 April 2009 | url-status=dead | archive-url=https://web.archive.org/web/20081206022433/http://www.ornl.gov/info/ornlreview/rev25-34/chapter1sidebar6.htm | archive-date=6 December 2008 | df=dmy-all }}</ref> then worth over $600&nbsp;million.<ref name="Silver">{{cite news | first=D. Ray | last=Smith  | title=Miller, key to obtaining 14,700 tons of silver Manhattan Project | year=2006 | url =http://www.oakridger.com/stories/051606/opi_20060516028.shtml  | work =Oak Ridger | access-date = 22 April 2009 |archive-url = https://web.archive.org/web/20071217171643/http://www.oakridger.com/stories/051606/opi_20060516028.shtml |archive-date = 17 December 2007}}</ref> Nichols had to provide a monthly accounting to the Treasury. The {{convert|1000|ozt|kg|adj=on}} silver bars were taken under guard to the Defense Plant Corporation in [[Carteret, New Jersey]], where they were cast into cylindrical billets, and then to [[Phelps Dodge]] in [[Bayway, New Jersey]], where they were extruded into strips {{convert|0.625|in}} thick, {{convert|3|in|cm}} wide and {{convert|40|ft}} long. Some 258 carloads were shipped under guard by rail to [[Allis-Chalmers]] in [[Milwaukee, Wisconsin]], where they were wound onto magnetic coils and sealed into welded casings.<ref>{{cite journal|title = From Treasury Vault to the Manhattan Project|url = http://www.pugetsound.edu/files/resources/7579_AmericanScientist-Article%20Treasury%20Silver.pdf|website = American Scientist|date = January–February 2011|pages=40–47|volume=99|last = Reed|first = Cameron}}</ref> Finally, they moved by unguarded flatcars to the Clinton Engineer Works. There, special procedures were instituted for handling the silver. When they had to drill holes in it, they did so over paper so that the filings could be collected. After the war, all the machinery was dismantled and cleaned and the floorboards beneath the machinery were ripped up and burned to recover minute amounts of silver. In the end, {{convert|155,645.39|ozt|kg}} or less than 0.036% was lost.<ref name="Silver" />{{sfn|Jones|1985|p=133}}{{sfn|Hewlett|Anderson|1962|p=153}} In May 1970, the last {{convert|67|ST|t ozt|abbr=off}} of silver was replaced with copper and returned to the Treasury.<ref name="Dedication, Innovation, and Courage">{{cite web |url=http://www.y12.doe.gov/sites/default/files/history/pdf/info_materials/y12-general-history-booklet.pdf |title=Dedication, Innovation, and Courage: A Short History of Y-12 |publisher=[[United States Department of Energy|Department of Energy]] |access-date=5 September 2015 |url-status=dead |archive-url=https://web.archive.org/web/20160125194958/http://www.y12.doe.gov/sites/default/files/history/pdf/info_materials/y12-general-history-booklet.pdf |archive-date=25 January 2016  }}</ref>

The XAX racetrack with two tanks and three coils was ready to train workers in August 1943. [[Bug (engineering)|Bugs]] were discovered, but were not aggressively followed up. The first Alpha process building, 9201-1, was completed on 1 November 1943. When the first racetrack was started up for testing on schedule in November, the 14-ton vacuum tanks crept out of alignment by as much as {{Convert|3|in|cm|0}} because of the power of the magnets and had to be fastened more securely. A more serious problem arose when the magnetic coils started shorting out. In December Groves ordered a magnet broken open, and handfuls of rust were found inside. Moisture was also a problem in its own right, as was the winding of the wire, which was too tight. Groves ordered the racetracks to be torn down and the magnets sent back to the factory to be cleaned and rewound.{{sfn|Manhattan District|1947e|p=4.1}}{{sfn|Jones|1985|pp=134–136}} Rigid standards for preparation and cleanliness were instituted to prevent a recurrence of these problems.{{sfn|Jones|1985|p=138}}

Training for the Beta tracks shifted from the XAX to the XBX training and development racetrack in November 1943.{{sfn|Manhattan District|1947f|pp=3.5–3.7}} A second Alpha I racetrack became operational in January 1944. The first Beta racetrack and the third and first Alpha racetracks, now repaired, became operational in March 1944, and the fourth Alpha racetrack in April 1944. A third building, 9201-3, contained a fifth racetrack that incorporated some modifications, and was known as Alpha I{{frac|1|2}}. This became operational on 3 June 1944. Work on the Alpha and Beta chemistry buildings, 9202 and 9203, commenced in February 1943, and was completed in September. Work on the Beta process building, 9204-1, began in May 1943, and was ready for operation on 13 March 1944, but was not completed until September 1944.{{sfn|Manhattan District|1947e|pp=S5–S7}}{{sfn|Manhattan District|1947f|p=S4}}{{sfn|Jones|1985|p=139}}

Groves authorized Alpha II in September 1943. This consisted of two new Alpha process buildings, 9201-4 and 9201-5, another Beta, 9204-2, an extension to the Alpha chemistry building, and a new Beta chemistry building, 9206. When 9206 opened, the old Beta chemistry building, 9203, was converted into a laboratory. Work started on the new Alpha II process buildings on 2 November 1943; the first racetrack was completed in July 1944, and all four were operational by 1 October 1944. The Alpha II racetracks were configured in a linear layout rather than an oval, although they were still called racetracks.{{sfn|Manhattan District|1947e|pp=S5–S7}}{{sfn|Manhattan District|1947f|p=S4}}{{sfn|Jones|1985|p=139}} In all, there were 864 Alpha calutrons, arranged in nine racetracks of 96. There were only 36 calutrons in each Beta racetrack, for a total of 288 calutrons, although only 216 of them were ever operated.{{sfn|Yergey|Yergey|1997|p=947}}

Work on the new Beta process building commenced on 20 October 1943. Equipment installation began on 1 April 1944, and it was ready for use on 10 September 1944. A third Beta process building, 9204-3, was authorized in May 1944 to process the output of the [[K-25]] gaseous diffusion plant. It was completed on 15 May 1945. A fourth Beta process building, 9204-4, was authorized on 2 April 1945 and was completed by 1 December 1945. A new group of Alpha chemistry buildings known as the 9207 group was commenced in June 1944, but work was halted in June 1945 before they were completed. Along with these main buildings, there were offices, workshops, warehouses and other structures. There were two steam plants for heating, and a power plant for electricity.{{sfn|Jones|1985|p=139}}{{sfn|Manhattan District|1947e|pp=S5–S7}}