Radioactive

Question 1

A. 3 basic types of radiation

Answer 1

1. Alpha Particles (most dangerous, cannot get thru skin, lethal if internalized
2. Beta Particles (high Energy e, stopped by plywood)
3. Gamma Rays (high Energy electromagnetic Radiation, m of concrete or H2O

Question 2

A. Half-life

Answer 2

the time a radionuclide decays to a more stable form

Question 3

B. Hazards of Radionuclides

Answer 3

• alter the chem and physical properties of the material when passed thru (DNA)
• When inhaled or ingested, some can bioaccumulate in the body where they will continue to emit radiation

Question 4

C. 5 Natural Sources of Radionuclides

Answer 4

1. Inhalation (depends on where you live)
2. medical diagnosis
3. comic radiation
4. gamma rays from soils and Rx
5. internal sources

Question 5

C. Industrial Sources

NORMs may be an issue for employees

Answer 5

1. oil and gas industry
2. mineral extraction -> processing
3. Forestry production
4. water treatment facilities
5. tunnelling + underground waste

Question 6

D. radioactive waste Catelogies

Answer 6

1. NORM (Naturally Occurring Radioactive Materials)
2. radioactive wastes resulting from the nuclear fuel cycle
3. atomic weapons produced from plutonium

Question 7

D1. NORM

Answer 7

-radioactive elements found naturally in our environment or their decay products
-low concentration in earth (U and Th)
-concentrate NORM -> TENORM (technology-enhanced)
has a higher radiation levels

Question 8

D2.1. The Nuclear Fuel Cycle

Answer 8

• Uranium mining and milling
• Refining and uranium enrichment
• Fuel fabrication
• Fuel consumption in nuclear reactors
• Fuel reprocessing
• Waste solidification
• Burial of solidified waste or reprocessing

Question 9

D2.1. Uranium mining and milling

Answer 9

• Concentrated ore

- Large piles of waste rock and tailings, low level source of radioactivity

Question 10

Fuel consumption

Answer 10

Produce low level radioactive (reactor wastes) which consist discarded equipment

Question 11

Fuel consumption

Answer 11

long half life -» difficult to deal w as a waste -» takes long to become Nonhazardous to the envi

Question 12

Fuel reprocessing

Answer 12

try to decrease the hazard of waste -> disposal (spent fuel and removes 235U & 239Pu)

Question 13

Burial of solidified waste or reprocessing

Answer 13

final disposal options

Question 14

High Level of Radioactive Waste (HLRW)

Answer 14

produces ionizing radiation with a strong ability to penetrate matter
Eg. spent nuclear, reactor fuel, small amount of medical isotopes

Question 15

Intermediate Level (ILRW)

Answer 15

-requires isolation and containment beyond several hundred years
Eg. radiation therapy; used radioactive component

Question 16

Low level (LLRW)

Answer 16

-losses all or most radiation in about 300yr

Eg. paper tower, floor sweeping, glassware…

Question 17

Uranium mine and Mil waste

Answer 17

-waste generated by the mining and milling of uranium ore

Question 18

D2.2. Levels of RW

Answer 18

1. High level
2. Intermediate level
3. Low Level
4. Uranium Mine and Mill Waste

Question 19

E. Disposal option for RW

Answer 19

-based on the time frame of the isolation and include:
+interim Storage
+Long Term Storage

Question 20

Long Term storage

Answer 20

• maintain integrity in 1000s year or much longer

- Goal: no long term monitoring required and negligible risk to the biosphere at anytime in future

Question 21

Short term storage safety requirements

Answer 21

i) cooling mechanisms (H2O/air)

ii) shielding mechanisms. (3mof H2O, 1mof concrete)

Question 22

CANOO Reactors

Answer 22

• duel bundles
• deemed waste after 1 year
• 30m away from an unshielded bundles
• dose 50-60 Sv/yr
• annual Rad Dose: 2mSv/yr

Question 23

E1. Interim Storage of HLRW

Answer 23

• # of Fuel rod about 2M
• the fuel is placed in wet storage (deep water pools with both cooling and shielding process, 10yr)
• Once cooled, then transferred to dry storage
  + still radioactive
  + steel or concrete container, above grd -> air cooling
  + 1 container = 70T, life = 50yr
  + above grd dry storage

Question 24

E1.2. Long term storage of HLRW - site criteria

Answer 24

site must be:

• geomorphically and structurally stable (area w no seismic activity, no volcanic activity, protect waste from landscape erosion)
• isolated from fractured bedrock (containment issue, if fractures, hard to clean up)
• isolated from grd H2O and grd h20 flow (no contamination to grd water)

Question 25

E1.2. Long-term storage of HLRW - Disposal site considered in past

Answer 25

i) burital within the Antarctic ice cap ii) Placement on the ocean floor at subduction zones +when the barrels transferred to the subduction zone, at high P ruptured the barrels and release content to the ocean + if not subducted, barrels become apart of accretionary wedge iii) Deep Geo Disposal (Terminal Storage) + store RW in engineered repositories within geo units where it will be isolated from zones of active grd H2O flow + mornitor the site for 1-2 gen and if goes well, permanent disposal of the waste

Question 26

E1.2.3 Deep Geological Disposal consideration

Answer 26

1. deep crystallize Rx (intrusive granite) 2. Deep salt beds (halite) 3. Deep shale beds 4. thick unsaturated zones

Question 27

Adv and Disad of deep salt beds

Answer 27

Ad: i) dry and impermeable to H2O ii) can dissipate large amt of heal iii) fracture that develops to self-seal Dis: i) can dissolve to create large cavern ii) can dissolve to create brines which corrosive iii) salt flow - halite flow toward to the surface wehen heated

Question 28

3 storage options in canadian

Answer 28

1. deep underground storage in canadian shield 2. decentralized storage at reactor sites 3. centralized storage in a disposal area * Federal gov accept combo 1 & 3 : a centralized repository deep undergrd in the canadian shield in Disposal Vaults

Question 29

Adaptive Phase management

Answer 29

1. waste will be retrievable indefinitely | 2. waste will be mornitored continuously

Question 30

Disposal Vault Design

Answer 30

- Lithology: Granite of the Canadian Shield - Mineral Value: low, - Depth: 500-1000m - Storage containers: corrosion resistant, containers last for 1000yr - GrdH2O flow: low exposure, k & K - Buffer material: material to surround the barrels to retard grdh2o flow if it entered the repositories - Backfill: Vaults tunnels + shift at closure

Question 31

Cigar Lake Uranium Deposit

Answer 31

- Located in nothern Sas - 11% of the world's uranium deposit, 430m below the Earth's surface (very permeable sandstone) - High grade ore is encased in clays which formed 1.3 Byr ago

Question 32

US Department of Defense Isolation Pilot Plant

Answer 32

- world's 3 deepest DGR, licensed for research and production of nuclear weapons -Location: 26km East of Carlbad New Mexico Depth: 650 -Lithology: Halite which is 900m thick -Material Accepted: Tranuranic low level (still Radioactive 24000yr)