EARLY S-SITE EXPERIENCES
By
Edward Wilder Jr.
The following is an account of the early days at S-site as I remember them. I have made no effort to confirm dates, but relative events are probably correct.
I hope that this account will enable future writers to have a feeling for some of the conditions under which the first atomic bomb was developed and built.
My introduction to the Manhattan
Engineer District was through the Navy. I was an enlisted man (draftee) and had taken the routine aptitude officer candidate tests. As a result of these tests, I was commissioned a Lieutenant (jg). At about this time (so rumor had it at Oak
Ridge) Eastman at Oak Ridge was behind in their production. Their explanation was that they were short of technical help. So, to fill this need, the next 150 naval officer candidates with engineering degrees being inducted were sent to Oak Ridge.
Most of these men had absolutely no military training. They were sworn into the Navy, bought a uniform, and reported to Oak Ridge all in a few days. This created situations that could be the subject of a good comedy.
Some of these men were very unhappy at Oak ridge. They had joined the Navy to fight a war, not to work in a factory. Also, some of them had influence in Washington. The result of their agitation
was that in March, 1944, the unit was disbanded. About 15 of the men were sent to Los Alamos. I was selected by Commander Bradbury, who interviewed us at Oak ridge, and was told that I would work on the development of procedures for machining a
material that had never been machined before. This material, I learned later, was high explosives.
I was not told where I was being sent, except that it was in the Southwestern
part of the U.S. My orders instructed me to report to 109 Ease Palace Avenue, Santa Fe, New Mexico. I was told that the Santa Fe address was not my duty station. So on March 1944, Ensign W. A. Wilson and I arrived at 109 East Place Avenue
and reported to Mrs. Dorothy McKibben and were told how to get to Los Alamos.
Junior officers were not allowed to have their families with them, but they were housed on a very nice (for Los
Alamos) dormitory called the Super Dorm. Meals were usually eaten at Fuller Lodge, although various mess halls were available. Food was cheap and very good.
The
area south of the town site was closed to non-technical traffic during work hours. The road through this area was what is now Anchor Ranch Road and West Road. The guard stations were in Los Alamos Canyon where the skating rink is now, and at State
Road 4. When the road was open to the Los Alamos public (holders of Post passes), the occupants of each car were given a pass that showed the time and the number of people, and one guard station, and they had 20 minutes in which to check out at the other
guard station.
Letters mailed in Los Alamos were put in the mail box unsealed. They were read and, if approved, were sealed and sent on by the censor; of they were not
approved they were returned to the sender. There was to be no evidence of censorship at Los Alamos to the outside world. Incoming mail was opened and read.
When I arrived, Los
Alamos was expanding. A story then current was that it was originally thought that 300 of the best scientists, engineers, and technicians would be brought in, locked up, and told to build the bomb. In 1944 we believed that we occasionally were
trailed by the FBI when we left the Hill (Los Alamos). When we traveled on Project business we were instructed to avoid conversation with strangers and if forced by circumstances to discuss where we were from, to say Washington, D.C.
We were discouraged from making friends in Santa Fe. As a junior officer, I did not qualify for housing in the Hill. When my wife and a friend’s wife decided to visit us in June
1944, I was instructed to tell them that they could not live closer than 100 miles from here. Albuquerque was OK, but Santa Fe was definitely out. They came anyway, and lived in a motel for several weeks. This was not satisfactory, so we
brought them to Bandelier (Frijoles Canyon, a U.S. National Monument). We lived there, camping in a tent until the end of August 1945 when the war was over and housing became available. Their living so close to Los Alamos was definitely against
the rules, but because there was little or no tourist traffic, we were not forced to move by the Project officials. To keep Security from noticing us, we always left the canyon on Sunday.
The weather in 1944-46 was different form the 1970 variety. The winters had more snow, and the summers more rain. The snow created problems because we had almost no snow removal equipment. The summer rains were
accompanied by violent thunder and lightning storms. These storms were so frequent and violent that shelters were constructed where the workers could go to get away from the explosive processing.
When the Los Alamos project was first established, the local public milk supply was inadequate and below standard. One of the local dairies was soon selling milk here. The story was that the Government had up-graded
the dairy so that its product would be acceptable. It was thought that the health hazard associated with working with TNT could be reduced if those concerned drank lots of milk, so free milk was provided for meals and mid-shift breaks.
I was assigned to Group X3 under Major Jerome (Jerry) O. Ackerman. Our responsibility was to develop and manufacture the high explosive system for the implosion bomb. This was done at S-Site.
It was on the south side as far away as possible from the rest of the Project. We believed that this was because of the danger involved in what we were doing. The personnel at S-site were almost completely military. We also believed that
this was because the work was too dangerous for civilians.
We worked a nominal 8 to 5 shift, but in practice everyone worked much more than this. The plant worked a 24
hr day, six days a week. The product in the early days of the Project was used to study materials under conditions of high pressure and shock, as well as to develop the explosive lens that would implode the nuclear components of the bomb. The operation
consisted of melting the high explosive (HE) and pouring it into molds whose shape was determined by theoretical calculations.
The men who conceived the idea of using explosives
to implode the bomb underestimated the difficulty of doing this. As a result, the first facilities built were completely inadequate. This is no adverse reflection on these men, who were the foremost men in this field. Rather, it is an indication
of the trouble that can be encountered in applying a familiar product to a new use. I do not know whether the planners of S-site anticipated continuous planning and construction of new buildings until just before Trinity day.
Notably absent from the first S-site buildings was anywhere machining could be done. The first HE castings were worked with hand tools, saws, rasps, and planes, to a template. This was done on boxes and makeshift stands
on the floor of building TA-16-26. One of my first memories I have of S-Site is that of a man sawing a big piece on HE on a Comp. B box. He had his knee on it just as if it were a block of wood. His left hand held a hose and directed a stream
of water onto the saw which he held in his right hand. I believe that explosives other than Comp B and TNT were processed before I arrived. I do not remember working with anything but Comp. B, TNT, and Baratol. Also, it seems that we were
making more full scale castings than scale models.
The kettles used in Building 42 wee stainless steel candy kettles, jacketed and steam heated. The agitator was driven
by an air motor. The molten explosive was poured from the kettle into a rubber bucket and from the bucket into the molds. The molds were steel weldments of the shape desired, a pentagon or hexagon. Small diameter tubes were fastened to the
inside of the steel for circulation of tempering water. The mold was finished with Cerrotru, a low melting casting alloy, around a master shape supported in the steel weldment. This Cerrotru covered the tempering coils and produced the mold that
was used in producing the explosive shapes. The mold had no inner or outer radius surface. The inner radius was produced by an insert, called a toadstool. The outer radius was produced by a surface attached to t eh mold cover. If the
piece being made was of Comp. B, the outer surface was spherical; if it was Baratol, the outer surface was shaped accordingly.
In Building 42 we made the first
effort to control the cooling patterns of the explosives as they solidified in the molds, by the use of steam heat on the body of the mold. Another device for improving the casting quality by reducing segregation was to use an air-motor-driven stirrer
in the casting during the cooling cycle. One of the duties of the casting room attendants was to raise these stirrers as the material solidified.
Here we should acknowledge
the debt that development of the bomb owes to self-adhesive tape. In my opinion, development of the explosive component of the bomb was greatly facilitated by the use of sticky tape. It seemed that if was used almost everywhere. I believe
that a Navy junior officer named Glenn Greening spent most of his time working with Minnesota Mining & Manufacturing Company (3M) in developing tapes for different purposes.
It was in
Building 42 that I saw a very dramatic demonstration of the inherent safety of the explosives we were processing. In the process we were using at the time, it was essential that the mold and riser unit be partially disassembled before complete solidification.
Otherwise, there was no easy way to take them apart. On this day a mold and riser had solidified, and one of the operations was using a bronze screwdriver and a rawhide mallet to ship the HE away so that the riser could be removed. This was standard
procedure, but on this day for some unknown reason there was an explosion under the screwdriver. It was a small explosion involving only one crystal and did not propagate to the rest of the explosive.
In these times there was no safety organization. After VJ Day, various safety men appeared, but they were uncertain and unknowledgeable, and accomplished little. The first real safety man at Los Alamos, in my opinion, was Roy
Reider.
After casting, the HE was taken by hand truck to building 43 to be machined. The equipment consisted of one K&T milling machine located in a barricade corner. The
other machines were wood-working type Delta drill presses. On liners and inner charges, the risers were machined off by using fly cutters, but the blades had a long spiral shape. Baratol was initially machined dry. The reason given was that
water would dissolve the barium nitrate. It was only after I put a piece of Baratol in a sink and let water drip on it over night to prove that this was not important, that Baratol was machined wet.
The first machinist at S-site was Ernest Richie. He was a little man who weighed about 110 pounds. I remember his lifting and machining full-scale lenses that weighed about 125 pounds.
All explosive operations produced great quantities of scrap. This was collected daily and burned in an area where the east end of Building TA-16-260 is now. For the burn, the material
was spread out in a single layer. Big pieces (125 pounds) were broken up into several smaller ones by hitting the with a heavy rubber mallet. The blows has to be very hard, and one man who did this was fat and always short of breath. Once,
as he was breaking us some HE, a piece flew into his mouth and he swallowed it. We did not know how this would affect him, but apparently he suffered no ill effects.
Several
times the explosive detonated instead of burning. The man in charge of the burning ground, and who ignited the HE, could speak clearly under normal conditions, but when he was excited he stuttered. Once when the burning ground exploded with a terrific
bang, I hurried there to see if anyone was hurt. I met him driving away from the burning ground. He stopped me and said “everything is all right”, the burning ground just blow up.” But it took about three minutes to say it.
Another time as we were spreading some cordite on the ground to burn it, it caught fire. I had always heard that a man in real danger will act impulsively to save himself, and this is what we
did. Every man ran in the direction he was facing when the fire started. Some ran faster than others. I only ran a short distance and threw myself into a ditch, completely ignoring the stickers and tumble weeds.
About this time, we began to have real trouble in manufacturing full scale lenses. Baratol components as made, inspected, and accepted would not, when put into a mold for overcasting, fit the mold. I remember
working many nights trying to find out what was happening to out process. We finally realized that the Baratol was changing dimensions. This is known and understood now. Then it was new, but we were able to develop enough of an understanding
to produce acceptable lenses.
The lens and inner charges were large and heavy, and the explosive material was rather fragile. We used three methods to protect
the HE from chipping. The finished casting was sprayed with the best “Bar Top” varnish available, a thin layer of felt was glued to one of two mating spherical surfaces, and blotting paper was glued to the sides.
As things developed and it looked as if a bomb would really be built, the practice assembly of the HE components was started. This was first done in Gamma build in the main Tech
area. As I said above, we were not bothered by Safety people. The assemblies were made on a floor area padded with wrestling mats. Sometimes the pieces did not fit very well. I remember someone hitting a piece of HE that was out of
line, as hard as he could with heavy rubber mallet. The Trinity bomb was assembled in building 516. At the end of the day, when the HE components were all put together, I thought that it should be guarded during the night. It was with great
difficulty that I convinced people that this should be done.
The Trinity test was conducted on July 16, 1945. Now we had to make a bomb that would be put
together in an airplane. This was done. The Hiroshima bomb was used on August 6th, and the Nagasaki bomb on August 9, 1945.
After Japan surrendered, things slowed down a great deal. The most notable event after VJ Day was in the winter of 1945 and 46 when the water supply to Los Alamos froze. When it was apparent that the pipe lines from
Guaje and Los Alamos canyons could not be kept from freezing, everyone who could possibly leave were encouraged to do so. This happened very quickly. I remember we set up a furlough-issuing line in the cafeteria. The Red Cross was there to
lend money to those who did not have enough cash. Water for the town and those people who stayed as trucked in. Every tank truck for hundreds of miles around was brought in and set to hauling water from the Rio Grande to Los Alamos. At this
time, it was estimated that it cost about 25 cents to flush a toilet. This was the low point in morale in the Hill. From there on things got better.