Nuclear Waste. What is Nuclear Waste? Waste that results from the use of radioactive materials...
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Transcript of Nuclear Waste. What is Nuclear Waste? Waste that results from the use of radioactive materials...
Nuclear Waste
What is Nuclear Waste?
Waste that results from the use of radioactive materials- Nuclear energy- Nuclear weapons- Hospitals, Universities, & Research
labs- Industry- Mining and Milling of Uranium Ore
Radioactive Waste
• Spent Fuel Rods• Irradiated elements from reactors• Radioactive coolant, gases, rods
Storing Spent Radioactive Fuel Rods Presents Risks
• Rods must be replaced every 3-4 years
• Cooled in water-filled pools
• Placed in dry casks
• Must be stored for thousands of years
• Vulnerable to terrorist attack
Dealing with Spent Fuel Rods
Fig. 15-24, p. 390
Radioactive Waste
Low Level• Emit small amounts of
radiation• Several States (SC, UT,
WA) accept these products
• 1980: low level radioactive policy act put disposal responsibility on states
• Must be stored 100 – 500 years
• Previously drummed & dumped in ocean
High Level • Initially emit large amounts of
radiation• Reactor equipment, fuel rods• Extremely toxic, continue to
produce heat• Remain radioactive for
thousands of years• Must be converted from liquid
to solid for disposal• Must be stored 10,000 –
240,000 years• 10 years after removal from
reactor still emitting enough radiation to kill a person 1m away in 3 minutes
How & where do we store high level radioactive waste?
1. Isolated areas2. Geologically stable3. NOT near water
Currently, generator facilities store these materials onsite! YIKES!
Possible Locations Discussed Include:
A.Underground rock formations – YUCCA Mtn.
B.Mausoleums in remote locations – above ground vaults
C.Antarctic Ice Sheets – Unstable, melting, movement
D.Ocean Seabeds in ocean ridges – threat of escape to environment
E. Space – Cost prohibitive
Yucca Mountain
• 1987 – DOE – Proposed storing nuclear waste at Yucca Mtn.
• 160km (100 miles) NW of Las Vegas
• Waste stored below ground in steel casks lined with lead
Yucca Mountain
• 2002 – Bush admin. & congress approved construction
• Critics – Location chosen as a political not scientific decision
Yucca Mountain
• 2008 DOE submitted license for construction to NRC which is still being reviewed
• NO DATE on Construction completion or opening
• Expensive: Total cost projected >$96 billion
Yucca Mountain *
• All high level material will be transported (trucks, convoys, rail)
• 1 to 6 shipments each day for 24 years to transport all currently existing material
• SAFETY CONCERNS
Radioactive Decay
Radioactive materials become less radioactive over timeThe decay process releases radiationRelease is NOT constant
Half - Life
Measurement of time it takes for one-half of a radioactive isotope sample to decay into another isotope