Opinion answers provided by Isabel Cisneros, Diana Pham, Karen Moxcey and others
and later checked by Mr. Jasmann
Nuclear Power Webquest APES
1. Uranium -235 decays naturally by alpha radiation and releases an alpha particle (two
neutrons and two protons bound), it undergoes spontaneous fission a small percentage of
the time but what makes it special is it can undergo induced fission, the nucleus absorbs
free neutrons and causes it to split.
2. Heat and gamma radiation (high energy protons) is released when atoms split; beta radiation is
also released after the fission. The energy released from one fission is less then how much the
original U-235 atom weights so the difference in weight is converted directly to energy at a rate
governed by the equation E = mc2.
3.
Picture with letters at: http://science.howstuffworks.com/nuclear-power3.htm
A. Containment structure: contains where the reaction occurs, holding the control rods, reactor,
and steam generator. Uranium pellets are arranged in rods, together in bundles, which are
submerged in water inside a pressure valve.
B. Control rods: in the uranium bundles, which absorb neutrons and raise or lower the control rods,
controlling the nuclear reaction rate (rods raised out when more heat is wanted).
C. Reactor: where the bundles are lowered to cause a reaction.
D. Steam generator: where water is heated to create steam.
E. Steam line: where the steam is carried to the turbine.
F. Pump: pumps in water to be heated.
G. Generator: Produces the power.
H. Turbine: spins the generator to produce power.
I. Cooling water condenser: Function below.
J. Cooling tower: I and J is the Cooling Tower which sucks in cold water from a pond and pumps it
within the turbine area to cool/condense the steam back into liquid water to be returned to the
steam generator.
4. Critical mass: If, on average, exactly one of the free neutrons from each fission hits another U235 nucleus and causes it to split, then the mass of uranium is said to be critical. The mass will
exist at a stable temperature.
Supercritical mass: If, on average, more than one of the free neutrons hits another U-235
atom, then the mass is supercritical. This will cause the reactor to heat up.
In creating a nuclear bomb, the mass of uranium is set up so that the U-235 atoms
split in the a single microsecond. If the mass is spread out in a thin sheet, many neurons
would just go into space, versus hitting other atoms
5. List 4 significant problems with nuclear power plants.
 When something goes wrong, the situation can turn catastrophic.
 Eventually spent nuclear fuel will decay to safe radioactive levels, but it takes tens
of thousands of years.
 All of this waste emits radiation and heat, meaning that it will eventually corrode
any container and can prove lethal to nearby life forms
 Mining and purifying uranium hasn't been a very clean process. Even transporting
nuclear fuel to and from plants poses a contamination risk
6. Definitions
Ore: a type of rock that contains minerals with important elements including metals.
Tailings: are the materials left over after the process of separating the valuable fraction from the
worthless fraction of an ore.
Mining: the extraction of valuable minerals or other geological materials from the earth, usually
from an ore body, vein or (coal) seam.
Materials mined: base metals, precious metals, iron, uranium, coal, diamonds, limestone, oil shale,
rock salt and potash.
7. Describe these three big category types of mining:
A. Surface mining: done by removing (stripping) surface vegetation, dirt, and if necessary,
layers of bedrock in order to reach buried ore deposits.
Three examples:
 Open-pit mining: recovery of materials from an open pit in the ground, quarrying or
gathering building materials from an open pit mine,
 Strip mining: stripping surface layers off to reveal ore/seams underneath, and
Mountaintop removal, commonly associated with coal mining, which involves taking the
top of a mountain off to reach ore deposits at depth. Most (but not all) placer deposits,
because of their shallowly-buried nature, are mined by surface methods.
 Mountaintop Removal
 Landfill mining: sites where landfills are excavated and processed.
B. Sub-surface mining: digging tunnels or shafts into the earth to reach buried ore
deposits.
Three examples:
 Drift mining: utilizes horizontal access tunnels,
 Slope mining: uses diagonally sloping access shafts and shaft mining consists of
vertical access shafts.
 Shaft Mining: vertical tunnels

Shrinkage stope mining: which is mining upward creating a sloping
underground room,
Additional sub-surface mining methods: Long wall mining, hard rock mining which is
mining of hard materials, bore hole mining, drift and fill mining, long hole slope mining,
sub level caving and block caving.
C. In-situ leaching (ISL): a less-common method; technique involves digging neither at
the surface nor underground. The extraction of target minerals by this teqhnique requires
that they be soluble, e.g., potash, potassium chloride, sodium chloride, sodium sulfate and
uranium oxide which dissolve in water.
8. Go to the Powertech USA website (second link given above) to learn some about Uranium.
Write a few comments about what you learned.
 Found in rock, soil, and water, and is as common as tin.
o 2 to 4 parts per million in most rocks
 Heavy metal, like lead.
 Most uranium exists as its isotope U-238 (99.2745 %). The rest is U-235 (0.72%) and U234 (0.0055%).
 U-235 fuel used in nuclear plants
 One ton of uranium can produce more than 40 million kilowatt hours of electricity
 All isotopes radioactive
OR Uranium can be found in low levels in all rock, soil and water, which occurs in most
rocks in concentrations of 2 to 4 parts per million and is also found in the oceans, at an
average concentration of 1.3 parts per billion. Most uranium exists as its isotope U-238
(99.2745 %). The rest is U-235 (0.72%) and U-234 (0.0055%). One ton of uranium can
produce more than 40 million kilowatt hours of electricity, equal to 16,000 tons of coal or
80,000 barrels of oil. Uranium and its decay products primarily emit alpha particles that have
little ability to penetrate through membranes, such as skin or even paper. Lower levels of
both beta and gamma radiation also are emitted. So basically I learned how radioactive
uranium is and how this radioactivity can be used and to what benefit it can be used. It was
interesting to learn that uranium usually emits alpha particles.
9. Scan the Centennial Project for Powertech USA to determine where this Uranium mine is
located using the third link above. Then go to the fourth link above to read Powertech’s
responses to Public Health and Environment questions. Read the questions regarding
radiation exposure, tailings, open-pit mining, air quality and reclamation plans and give a
response on whether you think Powertech is a credible source or not. Explain why.
This uranium mine is located in weld county, Colorado. (Denver?)
Public health: there won’t be any danger to human health from spills and surrounding areas will
be fine for livestock, keep radiation levels extremely slow and it does not cause cancer.
Environmentally: there will be no tailings, pit mining is last resort, the air will be monitored to
maintain air quality, and after use equipment will be removed and groundwater restored.
It isn’t a credible source because the responses are by the people who want to build the
mines and so are therefore biased and possibly dishonest or unreasonably optimistic.
OR I think Powertech is somewhat of a credible source, but not fully. Although it
provides somewhat reasonable answers, they all go in favor and are biased for the
issue in the questions, in other words “stretching the truth”. The answers are also
pretty straightforward and do not really provide a negative side of it all, even
encouraging and attempting to reassure the public with the bottom comment that
radiation is everywhere.
OR This source is probably reliable. It is already been established that radiation from
Uranium is not particularly dangerous. Furthermore, the Uranium is already there.
People concerned with radiation should be pleased that the mining companies are
removing it from our soils. Most objection to Uranium mining on cause of radiation is
rather paranoid. Other objections to the mine may be sound, although the company
does claim that it will restore the site and cites several regulatory agencies that will
keep it in line. People who complain about terrorist attack possibility should
remember that Fort Collins houses many government agencies
10. Read about the opposition to a uranium mine in Nunn, Colorado (start with
www.nunnglow.com) and what the fears may be. Do you feel that this is a credible source
of information? Explain why.
This is a creditable source of information because all the articles on the page are from reliable
sources but the same time, just from the title (Coloradoans against resource destruction) and the
article names (Greeley-Weld County League of Women Voters Opposes Uranium Mine, EPA
Documents Show That Uranium Mine Permit Would Allow Aquifer, Contamination Residents
Voice Uranium Project Concern) you can infer that it is extremely biased.
OR I learned that: Uranium can be found in low levels in all rock, soil and water, which occurs
in most rocks in concentrations of 2 to 4 parts per million and is also found in the oceans, at an
average concentration of 1.3 parts per billion. Most uranium exists as its isotope U-238 (99.2745
%). The rest is U-235 (0.72%) and U-234 (0.0055%). One ton of uranium can produce more than
40 million kilowatt hours of electricity, equal to 16,000 tons of coal or 80,000 barrels of oil.
Uranium and its decay products primarily emit alpha particles that have little ability to penetrate
through membranes, such as skin or even paper. Lower levels of both beta and gamma radiation
also are emitted. So basically I learned how radioactive uranium is and how this radioactivity can
be used and to what benefit it can be used. It was interesting to learn that uranium usually emits
alpha particles.
OR See my above response. The residents occasionally make valid claims, but often the
claims are rooted in illogical paranoid. Personally, I would prefer renewable energy or
thorium power to uranium-powered nuclear plants. However, I find a Uranium mine near
my home infinitely preferable to continuing fossil fuel use.