NtHlRMWable Resourcel. Vol. 6. No. I, 1997

Raw Materials Activities of the Manhattan Project on the Colorado Plateau

WUIiam L Chenoweth1,l

R«eived Oct.r 22. 1996: accepted Nov __r 20. /996

The Manhattan Project was a highly secret project during World War U to develop the atomic bomb, and included the acquisition of raw materials. It was carried out by the Army's Corps of Engineers Manhattan Engineer DistricL In the United States, 2.698,000 pounds of uranium oxide were acquiml at various vanadium mills on the Colorado Plateau, mainly from the treatmeDt of tailings. Geologic investigations conducted by a contractor, Union Mines Develop­ ment Corporation, laid the ground work for the exploration activities of the Atomic Energy Commission which succeeded the Manhanan Engineer District in 1947.

KEY WORDS: Uranium; Manbalran project; Coiondo pi .....

INTRODUcnON The name was taken from District Engineer, Colo­ nel James C. Marshall's office, in New York City Soon after the United Slates dropped atomic (Jones, 1958). In mid-August of 1943 the headquaners bombs on Hiroshima and Nagasaki, Japan on August of MED was transferred to Oak Ridge, Tennessee, 6 and 9, 1945, the public became aware of atomic and Lieutenant Colonel Kenneth D. Nichols was made energy and the Manhattan Project. The Manhattan District Engineer (Jones, 1958). Brigadier General Project was the code name used by the Anny's Corps Leslie R. Groves in Washington, D.C., was responsible of Engineers for the development of atomic weapons for the entire project and the procurement of the necessary raw materials The names of places such as Oak Ridge, Tennes­ during World War n. It was carried out under the see; Los Alamos, New Mexico; and Hanford, Washing­ d.ircaion of the Corps' Manhattan Engineer District ton, that were associated with the project became well (MED). known. The raw materials activities of the undertaking Prior to the establishment of MEn, the nation's were largely overlooked. This brief historical review atomic researcb program was undertaken by the Offlce summarizes those activities on the Colorado Plateau. of Scientific Research and Development With the entry of the United States into World War n, the work was assigned to the Corps of Engineers on June 19, 1942 (Jones, 1958). The Corps immediately began URANIUM PROCUREMENT plans to form a new district to carry on the work. DSM (Development of Substitute Materials) was fust Raw materials for the project were critical. In proposed as the name for the new district (Jones, 1958). 1942 the largest available sources of uranium were the To many, DSM seemed likely to arouse attention and Shinkolobwe Mine in the Belgium Congo (now Zaire) curiosity, and instead the Manhattan Engineer District and the Eldorado Mine at Port Radium on Great Bear was established on August 13, 1942. Lake, Northwest Territories, Canada. In the United States, uranium was known to occur in the carnotite

I Consulting Ocoqist. Grand Junction. Colorado SIB. deposits in the Salt Wash Member of the Morrison Z Correspondeac:e should be directed to William L. Chenoweth. Fonnation on the Colorado Plateau.

33 34 Chenoweth

These deposits, principally in southwestern Colo­ to contact Blair Burwell, General Manager of U.S. rado and southeastern Utah, had been mined for radium Vanadium Corporation (USV). Burwell informed from about 1910 to 1926. with some uranium and Leahy the Anny and USV were to build tailings treat­ vanadium recovered as byproducts. Since 1936 the ment plants at Durango and Uravan, Colorado, and same deposits had been mined for vanadium. At the acquire land at Grand Junction for a uranium refinery Naturita and Uravan. Colorado vanadium mills. large (P.C. Leahy, personal communication. 1993). Also tonnages of tailings containing low concentrations of with his orders was a letter from General Groves stating uranium were stockpiled. "to whom it may concern-if this officer asks for help. Due to the uncertainty of foreign supplies and the please assist." need for vanadium for war armaments, the federal A 55.71 acre tract of land was leased between government fonned the Metals Reserve Company in the Gunnison River and the Denver and Rio Grande December 1941. Metal Reserve's objective was to Western Railroad, two miles south of the city. The site acquire five million pounds of vanadium for the War was a gravel pit with a railroad spur line and contained Production Board's stockpile. Metal Reserve, which a log cabin. On this site, MED contracted with USV was part of the Reconstruction Finance Corporation to build and operate a small uranium refinery on a cost­ (RFC), began an ore-purchasing program, increasing plus-fixed fee basis. The Steams-Roger Manufacturing the base price paid for vanadium ore. At Durango, Company of Denver, Colorado, designed and built the Colorado, Metals Reserve spent S95,()()() to equip an refinery. The log cabin became the refinery's office. abandoned lead smelter for the production of 1.5 mil­ A plan of the Grand Junction refinery is shown in lion pounds of vanadium oxide (V 2005) per year. At figure 1. Monticello, Utah, Metals Reserve took over the opera­ The purpose of the refinery was to further concen­ tion of a vanadium mill (Metals Reserve Company, trate uranium and to remove vanadium from the green 1943). sludge which was received from tailing treatment plants at Durango and Uravan. A low grade uranium concentrate from the refinery was shipped to Tona­ Sources of Uranium wanda, New York for further processing into black oxide (Hewlett and Anderson, 1962). The flowsheets In September 1942, MED created a Materials of the tailings plants and the refinery are shown in Section to oversee the procurement of uranium. Lieu­ figure 2. tenant Colonel Thomas T. Crenshaw was in charge of On August 14, 1943, the War Department pur­ the Section. In August 1943. the Madison Square Area chased the Grand Junction site. A Mr. L. H. Hall was Office was formed to carry on this function. Colonel paid $10,500 for the property, which was to be used Crenshaw was transferred to Oak Ridge and Lieutenant for Project X, according to the deed in the Mesa Colonel John C. Ruhoffwas appointed Area Engineer. County Courthouse. In early 1945. he was succeeded by Major Wilber E. The Grand Junction plant operated from 1943 to Kelley (Jones. 1958). 1946. The green sludge shipped to the refinery from A survey of the vanadium activities on the Colo­ Durango and Uravan came from the processing of rado Plateau by Materials Section personnel in Decem­ some three million tons of tailings. The Grand Junction ber 1942, led to contracts with the two largest refinery recovered more vanadium from the green vanadium producers. United States Vanadium Corpo­ sludge than the entire Metals Reserve program actually ration and Vanadium Corporation of America, and with purchased (P. C. Leahy personal communication, the Metals Reserve Company. The uranium-producing 1993). The acquisition of land along the Gunnison activities of these organizations are discussed in the River and the establishment of an office in Grand following section by geographic locality. Junction in 1943 by the federal government would have a great economic impact on the city for many years afterward. Grand Junction, Colorado Uravan. Colorado On March 23. 1943. Second Lieutenant Philip C. Leahy arrived in Grand Junction to establish the The mill at Uravan had operated since about 1914, Colorado Area Engineer Office. Leahy's orders were first for radium. and then for vanadium processing. It Raw Materials Activities of the Manhattan Project on the Colorado Plateau 3S

c::::a a =F 0 OG ICO t e q ", ...

~ Buildini 8 I Fit_ eM Pnc:ipitatian 2 Uri" 3 Fusion Furnace 4 Boiler 5 Raaater 6 Laboratar, 1 Lavatory 8 Acid Pump 9 Fu" Oil Pump IZC 10 SodoAlh II loI_Anna 12 onstorate 13 Sludge and Soda Ash Bin 14 Warehouse and ChClngl 15 Office '4 16 Stara91 A OuatChamber I StaraoeTank , C RldCaklBin ClQ 0 Settling Tank E FUll Oil Storote Tanks ~ F Acid Starap Tonks CC? G Seal.. FIpn 1. Map of the Orand Junction refinery. from AEC files. was acquired by United States Vanadium Corporation bide and Carbon Corporation, a major contractor to (USV) in 1928 from Standard Chemical Company MEn at Oak Ridge. Tennessee. Late in 1943 the Linde (Hutf~ 1929). refinery was enlarged to process low-grade Belgium In 1939, prior to the establishment of MED, USV Congo ores until the end of 1944 (Hewlett and Ander­ built a small pilot plant at the Uravan mill which could son, 1962). produce a ~ uranium oxide (U30a) sludge from the In order to increase production, MEn contracted treatment of tailings (Merritt, 1945). Late in 1942, with USV to build and operate, at their own expense, MED contracted with the Linde Air Products Company a uranium-vanadium sludge plant. This plant would to build a pilot refinery at Tonawanda, New York, Rplace the pilot plant in mid-I943. Feed for the plant and to produce black uranium oxide from the Uravan would be stockpiled tailings and tailings from the cur­ sludge (Merritt. 1945). MEn would purchase the rent USV vanadium operations (Manhattan District sludge on a unit price basis as received at Tonawanda. Engineers, 1948a). Also at Uravan. the MED con­ Both USV and Linde were subsidiaries of Union Car- tracted with USV to c:onstn1Ct and operate a uranium- 36 Chenoweth

..... _Dica...... _Uaa __ and..,..._nl_In_tlo_D-.J.-..-----to- .... SoUda to Waste

llaat ~--4-___

t----..... --t FUtrate to Waste ------~------~

Dry Uraaima-Vaaaclbma Coacntrate to GraacI .JUIICUaa P1aat

t--.....-.aur Low Grade Sodium Dluranate Concentrate

Al\IIDUIa to Waste NaClOw -..--11--...... RaSa. Beat Precipitation &DCI Filtration t------t FIltrate to Waste

Figure 2. F10wsheets of the MED tailings treatment plants and refinery, from Lunquist and Lake (1955).

vanadium sludge plant on a cost-plus-fixed,..fee basis. 1971). In 1942, the MED contracted with VCA to The plant was designed and built by the Stearns-Roger produce a uranium-vanadium sludge from their Manufacturing Company. Feed for the plant consisted existing operations at the Naturita mill. The sludge. of stockpiled tailings at Uravan, tailings purchased containing 45%-50% U30 S, was sold to MED on a unit from the Vanadium Corporation of America (VCA) price basis and was shipped to the Vitro Manufacturing at Naturita, and tailings purchased from other small Company at Canonsburg, Pennsylvania. At Vitro, a vanadium mills (Manhattan District of Engineers, substantial portion of the high-grade Belgian Congo 1948a). The tailings were purchased by MED at a unit ores and all the VCA sludge were processed (Hewlett price, based on recoverable U30 S and vanadium oxide and Anderson. 1962). The tailings. at Naturita, (V20S) obtained the MED's refinery in Grand Junction. resulting from the manufacture of the sludge, were The tailings treatment plants operated from 1943 to considered too low-grade for further processing (Mer­ 1945. ritt, 1945). MED also contracted with VCA to buy the stockpile of vanadium tailings from past operations. These tailings were treated at the MED plant at Uravan, Naturita, Colorado Colorado (Manhattan District Engineers. 1948a).

Built by the Rare Metals Company about 1930, Durango. Colorado the Naturita plant was operated until about 1939 when it was purchased and rebuilt for vanadium production In 1942. the Reconstruction Finance Corporation. by the Vanadium Corporation of America (Merritt, a government agency, contracted with USV to convert Raw Materials Activities of the Manhattan Project on the Colorado Plateau 37 and operate an old lead smelter for vanadium produc­ In January 1943, Metals Reserve Company tion. The vanadium was supplied to Metals Reserve (MRC) agreed to produce a uranium-vanadium (U-V) Company. USV operated the plant for the government sludge at Monticello that was sold to MED on a unit until February 29, 1944, when the government vana­ price basis. The sludge which contained 45-50% U30s dium purchasing program was tenninated because of and about 2S~ V20, was shipped to the Vitro Manu­ adequate stocks. USV purchased the facilities from facturing Company at Canonsburg, Pennsylvania, for the Reconstruction Finance Corporation in August and additional processing (Hewlett and Anderson, 1962). operated them for the production of vanadium for com­ Tailings from the Monticello mill were considered to mercial sales until August 31, 1945, when the plant be too low in uranium for additional processing (Mer­ was closed (Albrethsen and McGinley, 1982). ritt, 1945). On February 29, 1944, MRC closed the During the 1943-1945 period, USV operated a Monticello mill and ceased production of both fused uranium-vanadium sludge plant at the Durango site, vanadium oxide (V 20,) and the U-V sludge. During under a cost-plus-fixed-fee agreement with the MED. its vanadium program on the Colorado Plateau, MRC Steams-Roger also built this plant. Feed for the plant acquired six million pounds of V20, for the govern­ consisted of vanadium tailings from past and current ment stockpile (Metal Reserve Company, 1943). operations. During the time Metals Reserve controlled In 1945, VCA leased the Monticello mill from the plant, MED purchased the tailings for USV to the Defense Plant Corporation and purchased the reprocess. The sludge was shipped to the MEn refinery remaining ore stockpiles from MRC. VeA processed at Grand Junction, Colorado (Manhattan District Engi­ the stockpiled ore plus ore from other sources, and neers, 1948a). sold a U-V sludge to the MED until the mill closed again in 1945 (Albrethsen and McGinley, 1982).

Gat~way. Colorado Moab, Utah MED purchased some 3,000 tons of tailings owned by Metals Reserve at a mill at Gateway, Colo­ The Vitro Manufacturing Company, through its rado (Merritt, 1945). The tailings were trucked to Ura­ local ore buyer, Howard Balsley, had been acquiring van for reprocessing at the MED plant. high-grade carnotite ores for the manufacture of ceramic colors, etc. MED contracted with Vitro to purchase their Moab stockpile of high-grade ore c0n­ taining approximately 52,000 pounds of UlO. (Man­ Colorado Rifle, hattan District Engineers, 1948&). This high-grade ore was processed at the Grand Junction refinery (P.C. MED ddennined that the tailings at USV's Rifle Leahy, personal communication, 1993). vanadium mill were too low in uranium for reprocess­ ing (P.C. Leahy, personal communicati~ 1993). OllwrAn!DS

Montic~/lo. Utah MEn contracted with vanadium mills at Blanding, Utah, Lorna, and Slick Rock, Colorado to In late 1940, the VCA opened a vanadium ore purchase their tailings for reprocessing at Uravan.. buying station at Monticello, Utah. in order to stimulate By January 1, 1947, the MED had acquired mining in the area. Within a short time, ore production 2,648,000 pounds of domestic uranium oxide at a cost increased sufficiently to justify construction of a vana­ of $2.072,330 (Table 1). This calculates to an average dium mill. In Seprember 1941, the War Production price of SO.77 per pound UJOa. Board approved VCNs proposal to build a mill. fund­ MEn acquired a tota1 of 18,938,000 pounds UlOa ing was provided through the government's Defense for the Manhattan Project (Table 2). Domestic sources Plant Corporation. The plant was to be operared by on ~e Colorado Plateau accounted for 149& of the total VCA for Metals Reserve. Actual construction started uranium acquired. Lieutenant Leahy had no idea what in February, and on August 24, 1942, the rust vana­ the uranium was beiDg used for. On July 17, 1945. die dium was produced (Albrethsen and McGinley, 1982). day after the first bomb was exploded in New Mexico, 38 Chenoweth

Table 1. Domestic Sources of Uranium" fee or profit to UMDC (Manhattan District Engi­ neers, I 948b). Company Cost To oversee the resource appraisal activities of U.S. Vanadium Corporation 1,782,000 $ 941,800 UMDC, the MED created the Murray Hill Area Office Vanadium Corporation of America 460,000 692,350 in New York City on June 15, 1943. Lieutenant Colonel Metals Reserve Company 270,000 216,300 Paul L. Guarin served as Area Engineer from June Vitro Manufacturing Company 52,000 71,880 1943 until March 1946. He was succeeded by Lieuten­ Others 134,000 150,000 TOTAL 2,698,000 $2,072,330 ant Colonel A.W. Oberbeck who served as Area Engi­ neer for about one month. until the Murray Hill Area 41 Manhattan Dislrict Engineers (1948&). was absorbed by the Madison Square Area in April 1946 (Manhattan District Engineers, 1948b).

Leahy's office and USV's office received telegrams from General Groves stating "MED's mission had been Organization of Union Mines Development accomplished" (P.C. Leahy, written communication, Corporation 1994). Only after the bombing of Japan did they learn of the atomic bombs. After the war ended, the sludge Union Mines set up offices in lune 1943 on the plants at Durango and Uravan were tom down and the 18th floor at 50 East 42nd Street in New York City equipment sold. The Colorado Engineer's office was and immediately began the recruitment of personnel. closed in March 1946. At that time, the refinery still James R. Van Fleet was selected as president of Union had six months work to do on the sludges (P.C. Leahy, Mines. Due to the extreme secrecy of the project, written communication, 1994). UMDC operated under the pretense of a large inter­ national mining company, interested in tungsten, molybdenum, and vanadium (Manhattan District Engi­ URANIUM RESOURCE INVESTIGATIONS neers, 1948b). Operations of UMDC were performed by four In February 1943, MED decided it needed to learn divisions: bibliographic search, field exploration, as much as possible about the uranium and thorium exploration research, and metallurgical research. resources of the world. Rather that establish a new The Bibliographic Search Division did the exami­ agency, MED decided to use the services of an existing nation of all available literature and the preparation of organization (Groves, 1962). Union Carbide and Car­ reports on all recorded occurrences of uranium ores. bon Corporation was a prime contractor to MED at About 67,()()() volumes were examined, more than half Oak Ridge, Tennessee. A subsidiary, United States were in foreign languages. Vanadium Corporation was a supplier of uranium to The Field Exploration Division sent oot field par­ the project. With such a background, Union Carbide ties of geologists and mining engineers who made agreed to undertake the resource evaluation assignment examinations in more than 20 foreign countries and (Groves, 1962), and Union Mines Development Cor­ in 36 states in this country. poration (UMDC) was created. A contract No. W-7405 The Exploration Research Division dealt with the Eng-78, effected May II, 1943, provided that all costs development of infonnation and methods for field should be reimbursed by the government, with no fixed exploration, in two principal fields: research as to the applicability of geophysical methods of prospecting, and mineralogical research. The geophysical research was concerned with the Table 2. Sources of Uranium" development of improved portable models of Geiger­ Muller counters for field use, procedures for the use Area Pounds UlO, Cost of these counters for quantitative or semiquantitative Colorado plateau 2,698,000 S 2.072,330 assaying, laboratory counters for accurate quantitative Eldorado mine 2,274,000 5,082,300 assays. and radioactive methods of locating and mea­ Shinkolobwe mine 13,966,000 19,381,600 suring ore reserves. TOTAL 18.938,000 $26,072.330 The mineralogical research was carried out first

41 Manhattan District Engineers (1948a). in the laboratories of the Union Carbide .and Carbon Raw Materials Activities or the Manhattan Project on the Colorado Plateau 39

Corporation at Niagara Falls, New York, and later, in drilling were especially noted. Stratigraphic sections of a laboratory established at the New York offices. This the Morrison and adjacent fonnations were measured work resulted in the development of a device for mea­ throughout the Colorado Plateau. All of this work was suring the maximum sensitivity of the bead test, which done under the disguise of looking for vanadium. was the standard chemical method of testing for the Although the reports of the UMDC geologists presence of uranium. Research determined that lithium were classified as SECRET by the MED, they could fluoride be used instead of sodium fluoride as a flux not contain the word uranium. Hence, special codes in the bead test were used: S.. 37 were uranium minerals; SOM was The Metallurgical Research Division devoted its uranium; and SOQ was uranium oxide (U30a). A typi­ first efforts to the development of suitable processes for cal description of an occurrence was, " ... 31 ft. long concentrating carnotite ores from the Colorado Plateau outcrop, avg. thickness 3.2 ft. of vanadium with some region. but before their work was fmished, they had weakly disseminated S-37. Avg. grade estimated to be done work on nearly every type of uranium ore better than 1% V20S and 0.25% SOQ. Horizon about occurring throughout the world. The Division made a 42 ft. above base of Salt Wash. Sample 3513 cut." working agreement with the Denver Equipment Com­ UMDC geologists also collected historical pro­ pany, Denver, Colorado, whereby the research investi­ duction information on the mines which had been gations were carried on in that company's laboratories, active during the radium and vanadium eras. From all with the use of the company's facilities and many of available information, Union Mines personnel esti­ its personnel. mated the pre-I 946 vanadium production of the Colo­ rado Plateau had been 1,348,942 toils of ore averaging 1.87% V20.5 and containing 50,336,225 pounds V20S Geologic Studies (Webber, 1947, fig. 59). Using information from chemical assays of 3,000 The majority of the work of the Field Exploration channel samples and a limited amount of drill holes Division was carried out on the Colorado Plateau. A provided by U.S. Vanadium Corporation and North field office was established in Grand Junction, Colo­ ContinentMines~ Inc., Union Mines geologists calcu­ rado, in July 1943, with Benjamin N. Webber, as Chief lated ore reserves for the Colorado Plateau. Reserves Field Geologist (Van Fleet, 1944). The MED liaison were classified as positive, indicated or inferred. Indi­ person in the UMDC office was Frank Belina, a civilian vidual blocks were tabulated by their average grades. mining engineer. Grade 1 was 0.15% U10S or better; Grade 2 was 0.08- After a brief geological training period by geolo­ 0.15% UJ0 8; and Grade 3 was O.OO~.08% UJOa• gists of USV, fieldwork by UMDC geologists began The combined total of Grades 1 and 2 for the on July 28, 1943, on the Navajo Indian Reservation. positive, indicated and inferred bloclcs for the Colorado By February 1, 1944, the Grand Junction Field Office Plateau was 4~12S,128 tonS of ore with an average had a staff of 48 geologists and engineers, divided into grade of 0.20% U30a and containing 16,500,512 11 field parties, plus a small administrative force (Van pounds U10a (Webber~ 1947, fig. 73). Webber also Fleet, 1944). indicated that he believed the geologic potential could Geologic work: on the Colorado Plateau was lim­ add an another four million pounds U30, to the Colo­ ited to the Salt Wash Member of the Morrison Forma­ rado Plateau resources. tion, and the Entrada Sandstone in the areas where the The ore reserves were distributed as follows: Col­ uraniferous vanadium deposits were located, such as orado, 12,370,826 pounds U30 S; Utah, 3,679,311 Rifle, Placerville, and Rico, Colorado. The Chinle For­ pounds; Arizona, 441,135 pounds; and New Mexico, mation was studied only in the Temple Mountain, Utah 9,240 pounds U30 a (Webber, 1947). All of the reserves area, since it was the sole area of radium production in were in the Salt Wash Member of the Morrison Fonna­ the 19105 and 19208 from the Chinle (Murphy, 1944). lion with the exception of a small amount in the Chinle All known exposures of the Salt Wash Member Formation at Temple Mountain, Utah and a smaller were prospected and mapped. Exposures of carnotite.. amount in the Entrada Sandstone at Rifle, Placerville, bearing minerals, prospects, and mines were all and Rico, Colorado. Since Union Mines was known mapped and described. Ore reserves were calculated to be affiliated with U.S. Vanadium Corporation, their from samples collected from outcrops and mines. competition, Vanadium Corporation of America, Areas where reserves could be developed by additional would not give Union Mines geologists access to their 40 Chenoweth

mines. Hence, no reserves were calculated for VCA All of these MED functions, and the numerous properties. UMDC recommended areas to be drilled government-owned facilities in which many of them to increase the ore reserves, but MED never approved were perfonned, were transferred to the U.S. Atomic this exploration. Energy Commission (AEC) by Executive Order 9816, Fieldwork on the Colorado Plateau was curtailed effective at midnight, December 31, 1946 (Jones, in early 1946. When the work was completed later 1958). The creation of the AEC transferred the devel­ that year, some 44 separate geological reports had opment of atomic energy from a secret military organi­ been written for the Colorado Plateau localities. These zation to a civilian agency, whose general activities included three reports for Arizona, 18 for Colorado, were a matter of public record. one for New Mexico, and 22 for Utah. The geologic Uranium procurement that was done secretly by investigations of UMDC were summarized in a report the MED was continued by the AEC, but that agency's by Webber (1947). need for uranium was made public. The price sched­ ules, bonuses, and other incentives of the AEC, created a prospecting effort unsurpassed in any other metal. Land Acquisition The geologic reports and maps of UMDC pro­ vided the foundations of the exploration activities of the newly created AEC. These documents were found As part of their investigations, UMDC geologists to be extremely thorough by AEC geologists, as very recommended areas that should be acquired by the few mineralized outcrops in the Salt Wash were missed federal government for the development of uranium by UMDC. Recommendations by UMDC geologists resources. On the Colorado·Plateau, UMDC acquired were the basis of planning many AEC drilling projects three properties: a 960-acre Navajo Indian lease in the throughout the Colorado Plateau. Carrizo Mountains of northeastern Arizona, held by When the AEC first published historic ore reserve Curran Brothers and Wade-USV; 42 unpatented claims infonnation, the agency (U.S. Atomic Energy Com­ of Gateway Alloys Co. on Calamity Mesa; in Mesa mission, 1968) listed the reserves for the United States County, Colorado; and the holdings of North Continent in 1947 as 4,400,000 pounds U 0 ' The AEC appar­ Mines, Inc. at Slick Rock, San Miguel County, Colo­ 3 S ently used only Union Mines' positive and indicated rado. The latter included a campsite, sman mill, 82 classes of Grades 1 and 2 to arrive at this conserva­ patented and unpatented claims, and miscellaneous tive figure. mining equipment. The total acquisition cost of the Unfortunately, the maps and reports were not three properties was $276,000 (Manhattan District declassified and made available to the public until the Engineers, 1948b). . late 19508 and early 19608. By that time, the uranium Although the U.S. Vanadium's and Lt. Leahy's boom had peaked, and it was too late for the prospector offices were only two blocks away from the UMDC or company geologist to benefit from this massive offices, in downtown Grand Junction, he did not know compilation of geological data. Since Union Mines of the activities of UMDC until the war was over (P.C. Development Corporation was connected to U.S. Leahy, written communication, 1986). This shows the Vanadium Corporation, Section 68, of the Atomic "need to known attitude that was prevalent during the Energy Act of 1946, prohibited USV and its successor, Manhattan Project. Union Carbide Nuclear Corporation, to use any infor­ mation developed by Union Mines to acquire public lands for uranium exploration. SUMMARY The Navajo lease in Apache County, Arizona and the claims in Mesa and San Miguel Counties, Colo­ During World War II, the Manhattan Engineer rado, were leased for mining by the AEC in 1949. The District, under the direction of the Army Corps of Navajo lease was canceled in June 1961 and the land Engineers. was charged with the development of returned to the Navajo Nation. The claims in Colorado atomic weapons. Its activities included research and are now controlled by the Department of Energy and development, engineering and design, the operation of are leased to mining companies. The mill site at Slick production facilities for weapons materials and compo­ Rock was never used by the AEC and was sold to nents, and the acquisition of uranium for the production Union Carbide Corporation in November 1957 of nuclear weapons. . (Albrethsen and McGinley, 1982). The Gunnison River Raw Materials Activities or the Manhattan Project on the Colorado Plateau 41

site became the headquarters for the AEC's uranium Huffard. J. B., 1929. Corporation acquires additional vanadium property in Colorado: Union Carbide and Carbon Corp •• The procurement and exploration activities in the western Carbidea. February 1929. p. 5-6. United States. The refmery Was dismantled, but the Jones. V. C~ 1958. United $tara Army in World W... D:, special log cabin (figure 1, no. 15) became the manager's studies. Manhattan: the Army and die atomic bomb: U.s. Army Center of Military History, WasbinstOn. D. C., 660 p. office, and is still in use today by the Department of Lunquist. A. Q. and Lab. J. L.. 19S5, History and treaclaofW'lllium Energy. The former warehouse and change room (fig­ plant flowsheers: Mining Congress Journal. v.41. n.ll, p. ure 1, no. 14) also are in use today as offices. 3$-42. MaubaUan Distric:t f.n&inccn, 19488, Manhattan Disaric:t history. book VB. volume I. feed maIerialJ and speciII procurement: U.s. Anny Corps of Engineers Report. Declassified by AEC in 1961. ACKNOWLEDGMENTS Manbaaan District Engincien. 1948b. ManbattaD DiRrict history. book VII. volume 2. pograpbicaI explOl'llioa: U.s. Army Corps otEn&ineen Report 43 p.• Declassiftecl by AEC in 1961. Recollections by Major (retired) Philip C. Leahy, Merritt. P. L.. 1945, Resume of prodactioa of uranium prodads Colorado Area Engineer for the Manhattan District, for' Manhattan District in the Colondo PI... Ilea: War Department, U.s. Engineer Office Report RMO-974. 6 p .• greatly augmented the uranium procurement section OpeD-tiled by DOE, 1983. of this report. He passed away on February 11, 1996 Merritt, R. C•• 1tn I. Tbe exlractivc metallUIJY of mwaium: Colo­ rado School of Mines, RaeaIdllDalitute. Golden. Colondo, in Boise, Idaho at the age of 83. .576 p. Mecal Raervc Company. 1943, Vaudium commibDeDtI: Metals Reserve Compaay report in die Natioaal ArdUvea. 4 p. Murphy. F. Mo. 1944. Report on Temple MoaDIIin district, SID REFERENCES Rafael Swell area. Utile Union Milles ~eIopment CoIp. Report RMO-46&, 72 p.• Declallif'aed by ABC in 19S8. U.s. A&omic Eneqy Commission, 1968. StaIistiQI data of the AIbretbsen. Holpr.Jr.• and McGinley. F. 8.. 1982., Summary history uranium industty. January 1. 1968: U.s. Atomic Energy Com­ of domestic uranium ptOcuremcnt under U.S. Atomic Energy mission Report GlO-l00. n p. Commission COIIIr'Ids. final report: U.S. Dep.rtment of Van Fleet. J. R.. 1944, Summary of Union Mines Dr:velopmeat Bnau. Report GJBX-22O(82). 162.p. COIpOI'8tion inveati~ to February I, 1944: Unioa Mines Oroves. L. R.. 1962, Now it can be COld, die stoiy of the ManbalIan DeYelopment COrp. Report. 15 p.• DecluIified by AEC in Project: tbrper and BroIben, New York. New York, 484 p. 1961. . Hewlett. R. G...... Andorson. o. 8.. Ir.• 1962. The new world, . Webber. B. N.• 1947. GeoIoaY and ore resourcea of the uranium­ 1939-1946. volume I~ a hiarory of the United Stares Atomic vanadium. clepoIidonal ~ of the CoIondo PIaIau Energy Commission: The Pamaylvania Stare University Prest. region: Union Mines Devdopmenl Corp. Report RMO-437. Univeraily Part. Penn.. 766 p. . 279 pi. 73 tip.. Declaaified by AEC in 1959.