Navajo Nation Nuclear Energy
Benjamin Wheeler
November 28, 2010
Submitted as coursework for Physics 240,
Stanford University, Fall 2010
During the 20th century nuclear power became a viable option as
technologies developed that could harness the atomic reactions of
radioactive elements. Today, nuclear energy is a highly controversial
source that has the potential to move the world off of coal and oil, but
could also result in a multitude of problems from radiation.
Historically uranium was mined in the United States to fuel the
Manhattan Project and later to produce weapons during the Cold War. A
major site for mining this material was the Navajo Nation from 1944 to
1986. Judy Pasternak's research and article in the Los Angeles Times
revealed many health concerns from mines that produced 3.9 million tons
of uranium ore during their operation. [1] This report seeks to
determine how much energy that uranium ore could have produced if used
for electric power rather than nuclear weapons.
According to Richard Muller's calculations, every fission of a U-235
atom produces about 215 MeV or 3.44 × 10-11 Joules of
energy. [2] U-235 is only 0.7% of natural uranium, with U-238 making up
99.3%, so we have .007 × 3.9 million tons = 2.73 ×
108 kg of U-235. A mole is 6.02 × 1023 atoms
and weighs 0.235 kg, thus the contained energy is
6.02 × 1023 atoms/mole ×
3.44 × 10-11 joules/atom ×
2.72 × 107 kg / 0.235kg/mole
= 2.40 x 1021 joules
Muller states that only a third of that energy actually becomes
electricity, so there is actually 7.99 x 1020 joules.
The Navajo Nation possesses a population of 250,000. [3] According to
Richard Eden in Energy Economics, the consumption of electricity per
person in the United States is roughly 104 kWh or 3.6 ×
1010 joules per year [4].
3.6 × 1010 × 250,000
= 9.0 × 1015 joules
The amount of energy from the uranium divided by the annual
consumption of electricity for the Navajo Nation by population is
6.3 × 1020 joules / 9.0 × 1015
joules/year = 70,000 years
The amount of uranium removed from the Navajo Nation through rough
estimates could have supplied the power required for the Navajo
population for 70,000 years.
© Benjamin Wheeler. The author grants permission to copy,
distribute and display this work in unaltered form, with the attribution
to the author, for noncommercial purposes only. All other rights,
including commercial rights, are reserved to the author.
References
[1] Judy Pasternak,
"
A Peril that Dwelt Among the Navajos," Los Angeles Times, 19
Nov06.
[2] R. A. Muller, Physics and Technology for Future Presidents
(Princeton University Press, 2010), p. 182.
[3] Sandra Pasqua, The Navajo Nation (Capstone Press, 2000),
p. 9.
[4] Richard Eden et al., Energy Economics: Growth,
Resources, and Policies (Cambridge University Press, 1981) p.
155-156.