Idaho National Laboratory Cultural Resource Management Plan

portion of steel hull designed to replicate the
aircraft carrier, USS Enterprise.
A1W was the first ship propulsion system
designed to have two reactors providing power to
the propeller shaft of one ship. The S5G reactor is
a prototype pressurized-water reactor designed to
operate in either a forced or natural circulation
flow mode. Coolant flow through the reactor is
caused by thermal circulation rather than pumps.
The S5G prototype plant was installed in an actual
submarine hull section capable of simulating the
rolling motions of a ship at sea (INEL 1969).
These prototypes were used for many years to
train naval personnel. A historic context and
building inventory assessment report that
addresses the historical significance of NRF
facilities has been completed under the direction
of DOE’s Office of Naval Reactors.
Boiling Water Reactor Experiment. In 1953,
the first of five reactors was constructed at the
Boiling Water Reactor Experiment (BORAX) area
to prove the feasibility of reactors in which the
coolant and moderator boils in the reactor core and
passes steam directly to the turbine for power
generation. The BORAX tests also attempted to
demonstrate the efficiency of power production
from this type of direct-cycle system. After
BORAX I was deliberately destroyed in 1954 to
determine this type of reactor’s safety under
extreme conditions, BORAX II was constructed in
the same area for further safety parameter tests and
to experiment with new core combinations.
The next reactor in the series, BORAX III,
was built in 1955 to determine if boiling-water
reactors could generate power. The determination
was made when BORAX III became the first
reactor to light an American town (Arco, Idaho)
on July 17, 1955.
BORAX IV operated from 1956 to 1958 and
demonstrated the stability of ceramic cores of
uranium-thorium oxide fuel elements. The last
reactor in the series, BORAX V, produced a
superheated dry steam wholly by nuclear means
for the first time in order to increase the efficiency
of this type of design and reduce the costs of
nuclear power.
Although no surface structures remain from
the BORAX programs, there is no question of the
importance they had in the development of reactor
safety parameters and the nuclear power program
(INEL 1976).
Test Area North. In the 1950s and early 1960s,
the Aircraft Nuclear Propulsion (ANP) program
was conducted at TAN (see Figure 21). During the
course of this program, which was designed to
prove the feasibility of nuclear-powered aircraft,
three Heat Transfer Reactor Experiments (HTRE-
I,-II, and -III) were conducted. Although no
nuclear-powered aircraft were ever built, HTRE
test results proved the feasibility of using heat
from nuclear power to operate aircraft turbojet
engines and resulted in a myriad of other scientific
contributions. Three additional low-power reactors
were operated in support of this program; the
Shield Test Pool Reactor, the Critical Experiment
Tank, and the Hot Critical Experiment.
Figure 21. Aerial photo of the LOFT facility
(demolished in 2006) and ANP hangar at TAN.
Following the development and success of the
Intercontinental Ballistic Missile program, the
need to restock conventional weapons arsenals,
and the desire to pursue space exploration, the
ANP program was terminated in 1961 by
presidential executive order. Two prototype
nuclear aircraft engines used in the HTRE tests are
presently on public display near the EBR-I reactor
complex. Although many of the structures
associated with the ANP have either been
demolished or stand vacant, the ANP hangar,
designed to house prototype aircraft, still exists
and supports ongoing programs at TAN (Braun
2006a).
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