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TRANSCRIPT
ON THE COVER:Although colored movies were taken of the Trinity test,they were of poor quality and have since deteriorated. Thiscover photograph, also showing the ravages of time,is the only existing color shot of the test. It was taken,surprisingly enough, by an amateur using his own camera.Jack Aeby, now of H-6, was working at Trinity withEmilio Segre studying delayed gamma rays. Segresecured permission for Aeby to carry his camera to thesite to record the group’s activities. Came the test and, asAeby says, “It was there so I shot it.” The picture wastaken from just outside Base Camp with a Perfex 33 camerausing 35 mm film. The photograph provided the basis forthe Theoretical Division’s earliest calculations of theTrinity weapon’s yield and was shortly confiscated by theArmy and first published after the announcement wasmade of the bombing of Japan.
Los Alamos Scientific Laboratory, an equal
opportunity employer, is operated by the Uni-versity of California for the United StatesAtomic Energy Commission.
L O S A L A M O S
b e g i n n i n g o f a n e r a 1 9 4 3 - 1 9 4 5
This is the story of one of the greatest scientificachievements of all time. It is the story of the found-ing of the Los Alamos Scientific Laboratory and itssuccessful secret mission to create the first atomicbomb, the weapon that ended World War II.
Information for this story was compiled andedited from previously published articles and bro-chures on Los Alamos history written by the staff ofLASL’s Public Relations Office.
PART I
s t a r t i n gp o i n t
m i l i t a r y & s c i e n t i f i c
r e a l i t i e s o f ‘ 1 9 4 3
Military considerations had government the deci-sion, by 1943, that an atomic bomb was desirable,as a means for bringing World War II to an end.Scientific considerations had governed the decisionthat an atomic bomb was probably feasible. Tech-nological considerations (already being worriedabout, though they were almost entirely in therealm of the unknown) had made it obvious thatthe atomic bomb would not be built in a day or amonth or a year.
The military picture was grim. The USA wasat war with Japan, Germany, and Italy. Americannaval power had not yet recovered from the disasterat Pearl Harbor. The Japanese had conquered thePhilippines, and Japanese naval power was at itsheight. American’ soldiers were heavily engaged inNorth Africa and elsewhere. The Germans hadbarely begun to suffer the reverses that would turnthe tide of war against them. (They surrendered ElAlamein late in 1942 and Stalingrad in 1943.) Gel--man scientists were working-no American knewhow ineffectively-toward an atomic bomb.
The scientific picture was exciting. The pheno-menon of uranium fission had been observed sev-eral years earlier and had been correctly inter-preted before 1940. It was known that at least onekind of uranium nucleus would divide (roughly inhalf’) upon absorption of a neutron, and that thisreact ion liberated energy plus more neutrons. InDecember, 1942, a Chicago group under EnricoFermi had succeeded in bringing about the world’sfirst man-made nuclear chain reaction-a reactionin which the neutrons from fission caused furtherfission at a sustained level.
The technological picture was wry nearly ablank, so far as atomic bombs were concerned.This was true not only because no one had evertried to build an atomic bomb, but because so muchfundamental scientific research remained to be donebefore anyone ever could.
Enough was known already, to suggest the magni-tude of’ the task, both scientifically and technolog-ically. It was known, for instance, that the essentialfissionable material-the heart of the bomb-wouldbe hard to prepare.
Fermi’s historic “pile” consisted of graphite
The military picture was grim in 1943.Right: Anti-aircraft gunners on USSSangamon fight off burning JapaneseKamikaze plane. Opposite: As oneAmerican scout falls in Italy, his com-rades dart into a doorway for tem-porary shel te r f rom the barrage .
blocks and lumps of natural uranium. Naturaluranium is more than 99% U-238, a heavy isotopeunfit for use in a bomb because of its tendencyto capture neutrons without fissioning. Uranium-235, the lighter isotope needed for a weapon, makesup about seven-tenths of one per cent of naturally-occurring uranium, Separating U-235 from themore abundant isotopes is extremely difficult, sincethe chemical behavior of the two isotopes offersno differences great enough to form the basis ofan efficient chemical separation process.
Slight differences in physical behavior include thefact that atoms of U-235 diffuse through porousmaterial at a somewhat faster rate than atoms ofU-238, and also the fact that the trajectory of afast-moving U-235 ion (an atom lacking one ormore of its natural electrons) will bend slightlymore, in a given transverse magnetic field, thanthe trajectory of any accompanying ions of U-238.Both of these slight behavioral differences (as wellas others, even less promising) were under inten-sive study by 1941.
In 1943 a separation plant based on the differentdiffusion rates was built at Oak Ridge, Tennessee,to produce enriched uranium (uranium containingmore than the natural proportion of U-235) forpossible use in a weapon. At the time of the found-ing of the Los A1amos Laboratory, construction ofthe Tennessee plant had not yet begun. There wasnot enough enriched uranium in the world for asingle bomb, or even for satisfactory laboratory in-vestigations of U-235 behavior. Material for thefirst uranium bomb would not be ready for morethan a year.
Minute quantities of a second fissionable ele-ment, plutonium, had been created at Berkeley inthe winter of 1940-41. Plutonium does not occur innature, but can be formed from uranium-238through a complicated series of events beginningwith the capture of neutrons by the uranium. Theconstruction of nuclear reactors to furnish neutronsfor this process began in 1943 at Oak Ridge, Ten-nessee (on a small scale) and Hanford, Washing-ton (on a large scale). At the time of the foundingof Los Alamos Laboratory, all the world’s pluto-nium could still have been piled on a pinhead,with room to spare.
Thus in January, 1943, not only was there nofissionable material for bomb-making; constructionof the Tennessee and Washington plants from
gun.Methods of devising a bomb deriving its explo-
sive energy from the fission of U-235 or Pu-239 werepurely specculative. The engineering effort was en-tirely in the future, and it would depend heavily onthe results of physical, chemical, and metallurgicalstudies of the two possible core materials. Thesestudies would have to be made on extremely smallquantities of uranium and plutonium, so that thenecessary knowledge would be gained by the timelarger quantities should become available.
Thus it was that the Los Alamos Laboratory, orProject Y as it was called, became the crucial part ofa super-secret nationwide research and developmentprogram known as the Manhattan Engineer Districtof the War Department. While other groups workedtoward development and production of materials,the mission of the Laboratory, under the directionof J. Robert Oppenheimer, was to pet-form thenecessary research, develop the technology and thento produce the actual bombs in time to affect theoutcome of the war. The story of how this was done,in the face of the problems just suggested andother problems soon to be encountered, has alreadybecome a classic of science and engineering. It be-gins with the choice of a site for the laboratorythat was to become, in the words of Dr. L I. Rabi,“the first line of defense of the United States.”
As the following chapter will show, geology andgeography played a remote but finite part in theselection of the location on the Pajarito Plateau inNew Mexico’s Jemez Mountains-an isolated schoolfor boys with “adequate quarters for the 30 sci-entists” who were all the project would need, or sothe founding fathers thought.
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t h e p l a c e
Early map makers, lookingblock of the Jemez Mountain
at the rectangularrange in northern
New Mexico, apparently noted with only passinginterest the circular shape formed by a series ofpeaks near the center.
The great circle, if they noted it at all, musthave appeared to them to be merely a curious setof connected mountain valleys, 8,500 feet above sealevel, separated by conical hills ranging in size fromknobs to 11,000-foot mountains. On their maps theygave these lovely alpine valleys their collective., , ,Spanish name: Los Valles del Monte. The easternrim of the circular range, overlooking present-dayLos Alamos, still bears the name of Sierra de losValles. Early geological reports refer to the regionas “the Vanes Mountain volcanic center, ” or some-thing equally non-committal.
It was not until sometime in the 1920’s that theidea that this unusual geographic feature mightactually be the rim of an ancient and extinct vol-cano began to gain acceptance. There never was anyquestion of the volcanic origin of the Jemez range.Even to the untrained eye thick layers of volcanicash, heaps of burned rock, cone-shaped hills andfumeroles, and bubbling hot sulfur springs, allgive unmistakable evidence of an open passage tothe underworld in the not-too-distant past.
The Indian name “Jemez” means “Place of theBoiling Springs. ”
Relief maps and aerial photography clearly saidthat here was once a huge volcano, but only servedto start another argument. One group of geologistsclaimed the big hole really was a crater, the top ofa volcano. If this were true, it would be the largestknown in the world, some 50 miles around and en-compassing nearly 200 square miles. The othergroup insisted it was a caldera, the huge saucer leftwhen a volcano collapses upon itself after havingspewed all its insides out. There are lots of bigcalderas, some even bigger than this one. ClarenceS. Ross of the U.S. Geological Survey, who hasdevoted 30 years to studying this region, is nowcertain it is a caldera.
The caldera and the surrounding peaks arc thefinal result of a series of upheavals dating back per-haps ten million years and continuing down to afew tens of thousands of years ago. Cone-shapedpeaks of varied size rising within the caldera, in-cluding 11,250-foot Redondo peak, are known to
be secondary volcanic upthrusts. They came intoexistence after the original volcano collapsed toform the great basin. The basin itself once was alake which left wave terraces visible today alongthe high rim. Ages ago the lake cut through therim and drained away down what is now the Jemezriver gorge.
The lush, grassy valleys between the secondarypeaks inside the basin have Spanish names, likemost places in New Mexico—Vallc Grande, VaneJaramillo, Valle de los Pesos, Vane Santa Rosa,Vane San Antonio. One of’ the valleys, the VaneGrande, is best known because it is the only onealongside a public road, State Highway 4. It is thelargest valley in the group, but it is only a fractionof the caldera. However, its name oftcn appearson maps and is popularly ascribed to the entirebasin. The error probably will stic:k.
The error is understandable. The Vane Grandeitself is huge enough, a vast sea of grass on whichgreat herds of cattle and sheep appear as ants. Inter-mediate forested hills block the view, of distant ad-joining valleys, so that only from an airplane up15,000 feet or more is it possible to see the wholecaldera. In winter, when the main peaks standstarkly around the blanket of snow that fills thevalleys, the circular shape is particularl y evidentfrom the air. But planes have been flying over therange only a short time—actually since World War11. The place names were established long beforepeople could view the whole magnificent panorama.So if’ you call it all the Vane Grande, not many willargue the point.
In the 1880's the Vane Grande was used formaneuvers by soldiers from Santa Fe’s Fort Marcy,who built a log fort on East Jcmez Creek. Navajohogans were standing along a ridge bordering VaneToledo, in the northeast section, until recent times.Apaches and Utes also passed this way in ancienttimes.
Somewhere in this period also a sawyer namedBuckman started a mill, one of several in the region,and hauled lumber to the narrow-gauge railroadstation across the Rio Grande from White Rockat what came to be known as Buckman’s station.Logging operations have continued off and ondown to the present-day in the caldera and aroundit.
High al t i tude view shows rugged canyon-pierced Pajari to Plateau below the
rim of the Jemez Caldera; part of the Vane Grande is visible upper r ight .
The Valle Grande, part of a giant volcanic caldera in the Jemez Mountains is 8,500 feet above sea level.
Next to the great Jemez caldera, the Valle Grande,and the high peaks, probably the most prominentgeological feature of the region is the long, nar-row plateau that extends along and halfway upthe eastern slope of the Jemez range, overlookingthe Rio Grande.
Edgar L. Hewett, early-day archaeologist, namedit Pajarito (Little Bird) Plateau. Lying at an alti-tude of between 6,300 and 7,300 feet above sealevel, this wooded, volcanic bench averages a mileor two or three in width. It is severely indentedalong its eastern edge by a series of deep verticalcanyons, where multi-colored layers of volcanicdeposits are exposed by erosion. Backed up against10,000-foot peaks, the plateau is covered thicklywith pinons, juniper, and many varieties of scrubon its lower slopes, and with ponderosa pine, fir,spruce, oak, and aspen on its upper levels. It sup-ports numerous small streams, a few of which arepermanent. The few clearings arc man-made.
Nomads probably wandered over the plateau forcenturies, as they did along the Rio Grande, butthey left no dates. There is no may yet to date withany precision the countless pctroglyphs that dec-orate the rocks of the region. Most of these crudesymbols are associated with adjacent ruins, which
can be dated somewhat by tree rings and by potteryand other relics. Other “picture rocks” arc nearnothing and seemingly relate to nothing, Theycould be of any age.
At Bandelicr and at Puye, Tsirege, Tsiping, andTsankawi, from Abiquiu to Cochiti, south-facingcliffs and adjoining mesa tops are the sites of count-less ruins. It is difficult for a trained observer to getout of sight of a telltale mound or cliff-openingthat speaks of early Pueblo occupancy, anywherealong the length of the plateau. Pottery sherds andobsidian flakes literally pave the ground in manyplaces. (In central Los Alamos, between the shop-ping center and the Lodge, a fenced area enclosesa partially excavated ruin of the 12th century, black-on-white pottery period, believed to be associatedwith the large Otowi Pueblo ruin in Pueblo Can-yon. Local archaeologists plan to restore the ruinas a public museum.)
There is no visible evidence in all these mem-orabilia, however, of any residence on the plateauprior to about 1150 A.D. Between that time and theSpanish occupation, many thousands of Indiansevidently lived and died on the plateau, farmingthe valleys by day for squash and beans and corn,retreating by night to the relative security of their
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cliff dwellings. They were harrassed by Apachesfrom the south, Navajos and Utes from the north,Comanches from the east, and by a changing cli-mate. About the only factor in their favor was theease of digging holes in the soft pumice cliffs forstorerooms behind their talus dwellings. Housingwas cheap and plentiful and natural defenses wereat hand. Nothing else could have been easy.
Indians existed here, in some fashion, for perhapsfour hundred years, when drought apparently drovethem to the Rio Grande bottom lands. They ar-rived just in time to meet the Spanish Conquista-dors, who jerked them in short order from stoneage freedom to slavery and near-extermination. Hadthey known what was in store for them, probablythey would have stayed in the hills and starved.
Some caves along lower Frijoles creek in Ban-delier National Monument are believed to havebeen a refuge, perhaps as late as 1700, for Indiansfleeing the returning Spaniards after the Pueblorevolt of 1680. But after that there is a blank in thehistory of the whole Pajarito Plateau, until the ar-rival of the first homesteaders in the late 1880’s.
(At Puye Cliffs, on the Santa Clara Indian reser-vation, Indians from the nearby Pueblo celebrateannually a fiesta at the site of a partially restoredruin which they insist is their ancient homesite. Butthe celebration is obviously just good clean fun, asit is of very recent origin. The Santa Clara Indiansalso maintain picnic, fishing, and recreation areas inbeautiful Santa Clara Canyon.)
There can be little doubt that early hunters ven-tured into the forests of the Jemez for the deer,bear, elk and turkey that still abound there. Sheep-herders and drovers from the haciendas of the RioGrande valley doubtless grazed their flocks in thehigh meadows and in the great caldera. But theyleft no record that the passage of a century hasnot obliterated.
The mountain men of the fur trade who openedthe West late in the 18th century may have trappedthe Jemez streams—there are still beaver in thelarger ones–but there is no mention of these moun-tains in their scanty journals. It is known that theytrapped the Rio Grande and the Chama, and it islikely therefore that they trapped the tributaries ofboth.
The archaeological wonders of the plateau werefirst reported in the 1880’s by Adolf Bandelier, forwhom the present-day national monument is named,
as a result of his explorations here between 1880and 1886. For a short time he lived with the CochitiIndians, who claim Frijoles Canyon as one of theirancestral homes. He camped in Frijoles also, prob-ably in one of the larger caves. From these experi-ences he obtained the material for his romantichistorical novel “The Delight Makers,” which seeksto reconstruct the lives of prehistoric dwellers inFrijoles Canyon, now headquarters for the Monu-ment.
Not only is the archaeological record of theplateau best preserved in Bandelier National Monu-ment, with its museum, guided tours and partiallyrestored prehistoric dwellings, but it is also thelocale for some of the earliest permanent settle-ments on the plateau.
A Boston judge named A. J. Abbott home-steaded Frijoles (Bean) Canyon about 1907. Abbottbuilt a stone and log house and planted an orchard.Some of his peach trees still bloom every springacross from the upper campground.
In 1925 George and Evelyn Frey took over theplace, known as Ten Elders Ranch, and started aguest ranch resort, about a quarter-mile west ofthe present visitor’s center. They brought suppliesin by cableway from the cliff top. Guests had toride in on burro-back, down a dizzy zig-zag trail,after boarding a buckboard at Buckman on the two-day journey from Santa Fe, crossing the Rio Grandeon a rickety plank bridge that washed out almostevery spring. There was no road down into thecanyon until 1933.
Ruins of the ancient pueblo of Tyuonyi, as well as manyprehistoric cliff dwellings, are included in BandelierNational monument, 14 miles from Los Alamos.
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Scene on a ranching homestead ofPajarito Plateau, photographedfore the founding of the Los AlaRanch School in 1917.
thebe-
mos
The old ranch buildings were torn down in 1938by the CCC when it built the present lodge andvisitor’s center. Mrs. Frey, a widow, has managedthe lodge since it was built.
Around Los Alamos, the earliest known occu-pancy was by summer bean farmers who came upfrom the valley. Bences Gonzales, who retired fromhis Laboratory employment in 1959 at the age of66, recalls spending summers near Anchor Ranch(now GT Site) where his father had been the first
settler in 1891. His wife’s grandfather, AntonioSanchez, was the first homesteader on PajaritoMesa (above present Pajarito site) in 1885, he re-calls. Some scraggly peach trees and a tumbledownlog cabin are all that are left of the old ranch. Be-cause of usually heavy snow the ranch was never oc-cupied in the winter, Gonzales recalls.
In dry years, the farmers hauled water to themesa top up an old trail still visible on the southside of Los Alamos canyon, just under Fire StationNo. 1. It was known for years as Dead Man’s Trail,because Sanchez was killed by a falling rock whilebuilding it.
The first permanent settlers in Los Alamos, whodug in for the winter with log cabins, frame housesand fireplaces, apparently arrived about 1911. Themesa was homesteaded by a man named HaroldHemingway Brook, who with a fellow lumberjacknamed Mack Hooper, filed on 160 acres of landeach in 1911. They called it Alamos Ranch, builthomes near the present Lodge building, and raisedbeans and wheat. Other ranchers settled on themesas and in nearby canyons.
Alamos Ranch also was a convalescent camp, andjust before the Los Alamos Ranch School openedmany people who came to Santa Fe from the in-dustrial areas of’ the East to recover from tuber-culosis, finished up the rest cure in the pine grovesof Los Alamos.
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T WO long-ago incidents involving water, theSouthwest’s most precious and unpredictable com-modity, were important in the chain of events thatled to the establishment of’ Los Alamos RanchSchool.
The first occurred in 1904 in the small, foothillstown of Valmora, N. M., on the cast side of theSangre de Cristo Mountains. A sudden flood washedaway the buildings of a new private school, onlyweeks before it was to have opened.
The second was a dozen years later, more than100 miles away in the grassy depths of PajaritoCanyon, when a stream chose to disappear sud-denly.
Affected by both unrelated outbreaks of naturewas a former Detroit, Mich., businessman, AshleyPond, who possessed an unremitting determinationto establish a school in New Mexico.
Pond’s Valmora catastrophe, during which hecarried his two-year old daughter, Peggy, to safetythrough the swirling waters, sent him back to De-troit until an inheritance made it possible to return.
Presence of the stream in Pajarito Canyon, color-ful cliff country containing Indian reminders sim-ilar to those at nearby Frijolcs, inspired Pond tochoose that site for, instead of a school, a ratherselective dude ranch. His Pajarito Club catered toa specific clientele,, the newly, affluent motorcar man-ufacturers of hometown Detroit, and enjoyed con-siderable popularity what with the abundance ofhunting, fishing and exhilarating climate.
When the stream departed (investigation showedit had gone underground at the head of’ the can-yon), Pond visited a neighbor to the north, H. H.Brook, who operated Alamos Ranch.
Pond bought out Brook’s interest and incorp-orated at the Los Alamos Ranch School,
Pond’s isolated school consisted of a conglom-mate of buildings, some of rough-hewn lumber butmost of logs. There was a trim main house with a
circling porch much like the farmhouses of theMidwest. There was a boggy area that alternatelyfilled and drained, Near stood a large barn. To theeast, reaching almost to the tip of the mesa, was alarge field that was part pasture and part cropland.West of the main buildings were service huts andcabins for the ranch hands. A dense forest of pinesslipped west down a gentle slope to a 200-acreclearing that extended to the rock base of the Jemezhills. This was range land, and had barns andstables.
For director, Pond solicited the services of aforest ranger named A. J. Connell, and by January1918, the Los Alamos Ranch School was ready forbusiness. The first pupil, enrolled on a tutoringbasis, was the son of a British consul with the un-likely but magnificent name of Lancelot InglesbyPelly.
The school grew, Faculty members were addedand new buildings went up. There was a hulkingtimber pile called the “Big House” to the northof the home. In 1924 another big log building waserected and named Fuller Lodge for one of the in-structors, Edward J. Fuller, whose father bought amajor interest in the school and helped finance itthrough a crucial period. It was a dining and recrea-tion hall. Rooms upstairs were used as an infirmaryand for putting up visiting parents.
A young man from Connecticut had been re-cruited to teach science—the first physicist on theHill. He was Fermor Church, who married PeggyPond a few years later.
Ashley Pond, his dream at last realized, retiredto Santa Fe.
Rows of crops of the Los Alamos Ranch School, growingon the site of the present Community Center. The rich
Enrollment in the school was first limited to 25,but success and expansion made it possible to ac-commodate 45 boys as the 1930’s arrived. A six-year study program was offered. Classes were smalland conducted informally.
Pond was a great believer in the vigorous life.Boys wore shorts the year round. They slept in un-heated sleeping porches but had a heated interiorstudy room in each of the residence cabins. Each ladwas assigned a horse, and pack trips into the Jemezwere common.
The bog at the south side of the mesa was workedover and became a 23-acre lake, a place for ice skat-ing in the winter, for swimming and even boatingin the summer. Its cracked-tufa bottom frequentlysprung leaks and the water dripped away, reappear-ing far out on the mesa. Adobe was packed on thebottom and eventually a six-inch pipe was run twoand a half miles from far up Los Alamos canyonto provide a surer water supply.
Inevitably, the pool was known as Ashley Pond.Commencement was a spectacular outdoor affair
with special guests seated on the log-columnedporch. Invited Indians performed dances, thenspread their craftwork on blankets for sale to thegoggle-eyed visitors.
During these years an incident occurred that hadgreat portent for the future. A visitor rode overthe mesas on a pack trip. His summer home wasacross the valley, in the high mountains at theheadwaters of the Pecos river, cast of Santa Fe. Hisname was J. Robert Oppenheimer.
Hc admired the setting, and thereafter oftenvisited the school. He remembered the place upon
volcanic soil of Los Alamos is still producing good cropsof vegetables for backyard gardeners.
being confronted with a momentous decision a fewyears later, when he was asked to advise the Corpsof Engineers on the selection of a secret laboratorysite with the following specifications:
1. It had to have adequate housing for 30 sci-entists.
2. The land had to be owned by the governmentor to be easily acquired in secrecy.
3. It had to be large enough and uninhabitedso as to permit safe separation of sites for experi-ments.
4. It had to afford easy control of access forsecurity and safety reasons.
5. It had to have enough cleared land, free oftimber, to locate the main buildings at once.
Los Alamos fitted these qualifications to a T. Allthe land around the school was national forest orcheap grazing land. The nearest town was 16 or 18miles away. And it had “plenty” of housing-for 30scientists.
Until the spring and summer of 1942, the Pajaritoplateau seemed about as far from war as was pos-
sible to get. Then, just as the annual summer pro-gram was in progress, school officials noticed a fre-quency of low-flying aircraft seemed to study thearea. Cars and military vehicles appeared on thecrest of the road that led up from the valley.
In autumn school officials were enlightened: theWar Department was interested in the property. OnDecember 7, 1942, the first anniversary of PearlHarbor, (and five days after Fermi achieved the firstnuclear chain reaction) notice was received in abrief communication from Secretary of War Stim-son that the school was being taken over. The Gov-ernment used condemnation proceedings but de-creed all records scaled immediately. They werenot released until 1961.
Parents were notified that the school was beingclosed, but were not told why. The Army allowed’until mid-February for the property to be vacated.In a final spurt of academic fire, class work was ac-celerated and by the time the boys left they hadcompleted the full year’s courses and had passedNew Mexico tests to prove it.
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