Transcript Nuclear Waste

Nuclear
Waste
By: Suhani Ray, Sunita Prasla, Sibnish Ali,
Rachael Milne, Jessica Chou
1. What exactly is nuclear (radioactive) waste?
2. So can you just throw the waste into any
trash place?
3. Electric power>>(rods) heat>>steam>>generator>>electricity
Suhani Ray
Suhani Ray
• Radioactive waste has different
levels of waste
1. High level- “Waste from power plants that is
highly radioactive is called high-level waste.”
2. Low level- “Waste that is only slightly
radioactive and gives off small amounts of
radiation is called low-level waste.”
• Low level special sites = isolated
environment
Suhani Ray
Suhani Ray
1. What sources account for the accumulation
of nuclear waste? Which ones contribute the
most waste?
• Generated from hospitals, laboratories, and
industry
• Includes clothing, tools, rags, papers and
filters
• Worldwide, it is 90% of volume of the waste,
but is only 1% of the radioactivity.
Rachel Milne
Intermediate-level Waste
• Involves, chemical sludge's and reactor
components, processing and enrichment
plants, from nuclear weapons facilities, and
from nuclear power plants ,also it is has
contaminated materials from reactor
decommissioning.
• It makes up 7% of the volume of the waste,
and 4% of the radioactive of the whole
Rachel Milne
High-level Waste
• Comes from spent fuel from nuclear
reactors.
• It Contains the highly-radioactive
fission products and also some elements
with long-lived radioactivity.
• It is only 3% f the volume of waste, but
it holds 95% of the radioactivity.
Rachel Milne
2. Can nuclear waste be made
safe?
• Nuclear waste can be made
safe in a way by making it
stable and no because
there are solutions to it by
placing the waste 500
meters below setting below
the surface known as
geological disposal.
Another solution is to
reduce the mass of longlived, high-level waste
which means partitioning
and transmutation.
Sibnish Ali
3. What are the Short Term
Solution?
• Currently, after a period of temporary
storage when the most radioactive
product have had the chance to decay
high level waste from the spent nuclear
fuel is incased in a borosilicate glass and
sealed in stainless steel drums.
Suhani Ray
4. Are there presently any long-term
solutions to storage of nuclear waste?
• At the moment there are three kinds of
options being considered for permanent
nuclear waste storage.
• MOX fuel burning method (Mixed Oxide)
• Verification Method
• Subductive waste Disposal Method
Rachel Milne
MOX fuel burning method (Mixed
Oxide)
• Method in which plutonium is mixed with uranium.
• When plutonium burns, nuclear fission occurs.
• More of the plutonium is burning, which produces
more energy and faster.
• Although it produces more plutonium, it is less
dangerous in the environment.
• So…. The amount of plutonium is reduced, leaving the
remaining, less usable for weapons and easy to
dispose.
Rachel Milne
Verification Method
• This method involves the mixing of weaponsgrade plutonium and radioactive waste from
civilian reactors.
• It is placed in borosilicate glass logs.
• The logs will be dug in deep boreholes.
• Plutonium could be efficiently encased and
isolated to allow the decaying progress to
occur.
• But it is possible for a leakage to occur, or it
could be mined in the future.
Rachel Milne
Subductive Waste Disposal
Method
• This method is the placement
of the waste in a subducting
tectonic plate.
• The plate reabsorbs, and
along with it, the waste. It
will be dispersed into the
mantle.
• Using this method would
prevent any radioactive or
nuclear waste from mixing
with water , stop access for
the production of nuclear
weapons, remove the waste
from harmful positions to
the environment, and be safe
from any marine life in the
world.
Rachel Milne
5. Proposed solution and controversy of
Yucca Mountain in Nevada.
Problems:
-U.S. needs a
repository site
for high level
waste
-Companies say
storage areas are
almost full
Jessica Chou
Jessica Chou
5. Proposed solution and controversy of
Yucca Mountain in Nevada.
Proposed Solution:
-1987 Department of
Energy chooses Yucca
Mountain northwest of
Las Vegas, Nevada
May 16, 2006 The Senate Energy and Natural
Resources Committee hearing on the Yucca
Mountain nuclear waste project
Jessica Chou
5. Proposed solution and controversy of
Yucca Mountain in Nevada.
Controversy:
-Costs a lot: $57.5
billion
-Takes to long: about
30 years
-Target for Terrorists:
nuclear waste on the
road can be targeted
by terrorists
- Will be full capacity:
by about 2020
shipment of mixed nuclear waste from rom a federal lab in Idaho
Jessica Chou
5. Proposed solution and controversy of
Yucca Mountain in Nevada.
Controversy:
- Economical objection: might slow business and tourism
- Scientific objection: earthquakes and volcanic eruption may
occur. Water can leak into storage room
- Political opposition: Lawsuits by the State of Nevada and other
groups
Jessica Chou
6. What are the different levels of
nuclear waste and what dangers does
each level poses?
• Low Level Waste
• High Level Waste
Sunita Prasla
Low Level Waste
• Low-level waste includes items that have
become contaminated with radioactive
material or have become radioactive through
exposure to neutron radiation.
• The radioactivity can range from just above
background levels found in nature to very
highly radioactive in certain cases such as
parts from inside the reactor vessel in a
nuclear power plant.
Sunita Prasla
High Level Waste
• High-level radioactive wastes are the highly
radioactive materials produced as a byproduct of the
reactions that occur inside nuclear reactors. Highlevel wastes take one of two forms:
-Spent (used) reactor fuel when it is accepted for
disposal
-Waste materials remaining after spent fuel is
reprocessed
Sunita Prasla
7. What elements are involved in #6
and how long do they remain
radioactive?
• Short Term Radioactive
-Uranium-235, Cesium-137, Strontium-90
• Long Term Radioactive
-Plutonium- 239, Americium- 243
Sunita Prasla
8. Effects of nuclear waste on the environment.
Does it pose an immediate threat to the general
public?
Effect on Environment:
- Low level waste in
concrete encased in
steel drums has been
dumped in the Atlantic
Ocean. If drums leak
liquids, fish nearby
become irradiated
- Metal drums of low level
waste at some sites
have leaked radioactive
fluids into the soil and
groundwater
08/26/1997 Japan's nuclear power program said it is
Jessica Chou
investigating whether radioactive liquid has seeped into
groundwater from the rusting drums in the concrete
pits
8. Effects of nuclear waste on the environment.
Does it pose an immediate threat to the general
public?
Immediate threat to general
public?
- No not an immediate threat
because waste is kept secure
from the public but in the
future irradiated soil,
groundwater, and animals
may affect humans
- Waste underground would
protect it from being
exposed to environmental
factors above ground that
could cause the waste to
break down into radioactive
particles that could be
scattered by air or water.
Jessica Chou
9. Countries with the most Nuclear
Waste
1. United States
2. Canada
3. France
4. Japan
5. United Kingdom
6. Germany
7. South Korea
8. Sweden
9. Spain
10. Belgium
Jessica Chou
Storage pond for spent fuel at UK reprocessing plant
9. Countries with the most Nuclear
Waste
Jessica Chou
9. Countries with the Most
Waste
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
Canada
United Kingdom
Sweden
France
Finland
Belgium
Switzerland
United States
Japan
Germany
Jessica Chou
10. Discuss what impact the
nuclear age has had on civilization?
• It started in 1950
and there was a
storage problem
but United State
Atoms for Peace
Initiative take the
residue of the fuel
and dispose of it.
Sibnish Ali
Conclusion
•
•
•
•
High level = highly radioactive
Low level = low radioactivity
When did nuclear waste start?
Fission
• http://gtmmedia.discoveryeducation.com/videos/pmp/vid
eos/wm/1MB/60290-HAVTC_1Mb.wmv
Suhani Ray