part of the
harbor, the
Chariot experiment for excavation of an Alaskan
testers decided to establish all radiation back-
grounds associated with plant and animal welfare before the test
took place.
On September 19, 1957, in the test series Plumbbob, a nuclear
test device with an energy release of 1.7 kt was fired in a tunnel under a mountain at the Nevada Test Site.
The Shot was named
Rainier.
The test objective was to to develop a weapon testing
technique which would eliminate fallout;
be independent of
weather conditions; and have no off-site effects such as noise,
flash, and shock.
The principle problems of the test concerned
the depth necessary for containment of radioactivity, the magnitude of the induced ground motions and their effects on local and
off-site structures; and the possiblity of ground-water contamination.
Before the Rainier Shot the Test Division at Livermore
made a study of the concept and feasiblity of underground testing
in Spring
1956.
LRL created a motion picture
"atomic weapons"
film on the proposed uses
of
in the UCRL Plowshare Program for presentation
at the Geneva Conference on Peaceful Uses of Atomic Energy in
September 1958.
Plowshare obtained increasing importance at the
Laboratory by the late 1950s and throughout the 1960s.
The Plowshare work at the Livermore Laboratory was done primarily by K Division, but A and B Divisions (Weapons and Devices)
designed nuclear explosions specifically for Plowshare use.
Chemistry Division performed the radiochemistry and physical
chemistry parts of the program.
L Division (Test) completed
field experiments, and the Physics Department assisted in longrange code development for equation-of-state work.
By using
these techniques,
ity explosions
the laboratory calculated shock waves and cav-
of earth materials
in bedded salt
(Gnome),
granite
(Hardhat), dolomite (handcar) and salt dome (Sedan). The Laboratory developed special calculation codes, TENSOR and PUSH for
duplicating observed high-explosive and nuclear exposive cratering. Nuclear debris was recovered by drilling, and samples were
analyzed at Lawrence Livermore for isotopes produced by neutron
capture in uranium targets.
Some Plowshare experiments were directed toward the use of
nuclear explosions to produce heavy or transuranic elements.
These tests involved exposing the target to intense neutron flux
produced by
the detonation.
Following the neutron exposure, a
series of beta decays occurred in chain and produced isotopes of
elements
with higher atomic numbers. Such a target under neutron
exposure was equivalent to irradiation in nuclear reactions.
This method was used, for example, in the Mike event at Eniwetok
in 1956.
The debris from the explosion was rich in transuranium
elements, including einsteinium and fermium plus isotopes of plutonium, americium, curium, and californium.