Lectures On Nuclear technology and Environment(2008 07@The University of Tokyo)
1. 人間環境デザインスタジオ
Human Environmental Design Studio
1:00-4:15 pm
June 24, July 1, July 8, and July 15, 2008
at
Graduate School of Frontier Sciences
The University of Tokyo
Joonhong Ahn
Department of Nuclear Engineering
University of California, Berkeley
2. Who am I?
• Professor, Dept. of Nuclear Engineering, UC Berkeley
• BS, NE, Todai, 1981 (Prof. Iwata)
• MS, NE, Todai, 1983 (Prof. Kiyose/Suzuki)
• PhD, NE UCB, 1988 (Prof. Pigford)
• D. Eng, NE, Todai, 1989 (Prof. Suzuki)
• JSPS Junior fellow, 1988-1990
• Lecturer, Todai, 1990-1993
• Assoc. Prof., Tokai U., 1993-1995
• UCB since 1995
• third generation Japan-born Korean
3. Objective of the class
• This series of lectures introduces
– fundamental technical facts about
environmental issues with nuclear power
utilization.
– discussions on long-term environmental
safety of geologic disposal, including
• How engineers have established technologies for
securing and assessing long-term safety, and
• How societal agreement has (not?) been
developed, particularly in US.
4. Syllabus
• June 24 – Technical basis for nuclear environmental
issues
– Nuclear fuel cycle and the environment
– Geologic disposal
• July 1 – Performance assessment of geologic disposal
– Performance assessment
– Can the environmental impact be reduced by recycling?
• July 8 – Societal and ethical issues of geologic disposal
– Development of societal agreement for geologic disposal
– Ethics in/of geologic disposal
• July 15 – International aspects of nuclear power
utilization
– (Introductory summary for nuclear activities in India)
– (Comparative discussions among Japan, US, and India)
5. Format of class
• Prerequisites
– Fundamental knowledge about nuclear fission
– Fundamental knowledge about chemical reactions
• Each topic consists of:
– ~ 1 hour lecture for summarizing basic facts
– discussion
• Reading materials/text books:
– Relevant reading materials will be given to
supplement class discussions upon request.
• Grading:
– ?? (Ask Prof. Iwata!)
9. Fuel consumption and waste generation from various
electricity generation sources for 1GWe.year
Fuel consumption [ton] Waste generation [ton]
CO2 5,000,000
Crude oil 1,400,000 SO2 40,000
NOx 25,000
dust, particles, ashes 25,000
CO2 6,000,000
Coal 2,200,000 SO2 120,000
NOx 25,000
dust, particles, ashes 300,000
(Uranium) (28.8)
Nuclear 30 (Plutonium) (0.3)
Fission products 0.9
10. Comparison with Fossil Fuels
Chemical reaction
12
C + O2 → CO2 + 4 eV
12
y 200MeV
Nuclear Fission 0n
1 x
2.43
92U
235
94Pu
239
92U
238
0n
1
per atom [eV] per gram
[W•hr]
92U
235
Carbon ~4 ~ 10
Uranium ~ 2E8 ~ 2E7
11. Uranium
• Uranium is mined as U3O8.
• It is composed of;
– 99.3% by weight 92U238
– 0.7% by weight 92U235
• 92 U235 is fissionable with slow neutrons, i.e.,
thermally fissile.
Light-water reactors (Current fleet of commercial
reactors)
• 92 U238 is fissionable with only fast neutrons.
– However, 92U238 is a “fertile” isotope, generating
239 (thermally fissile).
94Pu
Reprocessing and recycle of spent U fuel
13. Uranium mining technologies
Underground
Open Cast Mining Mining
Production per Method (%) as in 2003
(total 35 772 t U)
Co-/By-
product
ISL m ining
20% 11%
28% 41%
Open pit Deep
In-Situ Leach (ISL) m ining underground
m ining
Mining
14. Uranium Resources (million ton)
Known Conventional & Undiscovered Resources
Identified Resources
Cost range Reasonably Inferred Prognosticat Speculative
(US$/kgU) Assumed ed
Resources
(RAR)
< 80 2.64 1.16 1.70
80 – 130 0.66 0.28 0.82
>130 4.56
Unassigned 2.98
Subtotal 3.30 1.44 2.52 7.54
Total 4.74 10.06
14.80
IAEA Red Book 2005
15. Global Uranium Resources & Production
Uranium Production
(total 41.360 tU in 2005)
USA Other
2% 9%
Uzbekistan
6% Canada
28%
Namibia
7%
Russian
Federation Identified (RAR+Inferred) Uranium Resources
below $130 /kgU (total=4 743 000 t in 2005)
8% Other
Niger Uzbekistan
2% 20%
A ustralia
8% A ustralia 24%
Russian
Kazakhstan 22% Federation
10% 4%
Niger
5%
Kazakhstan’s large resource is
Kazakhstan
planned to be utilized by in-situ 17%
leaching. Brazil
6% Namibia
6% USA Canada
7% 9%
16. Nuclear Fuel Cycle and Waste Generation
LLW 1,000 drums
~0.2 ton U
27.3 ton
26 ton U
27.5 ton
0.95 ton FP
0.27 ton Ac
0.24 ton Pu
26 ton
~ 0.5 ton U TRU/LLW
< 0.26 ton U
165 ton 0.95 ton FP
(0.3%U-235) 167 ton 0.27 ton Ac
100,000
ton ore
1 GWe, LWR, 1 year
Reprocessing scheme
0.2% U3O8 Thermal efficiency 0.325
~ 1 ton U
= 181 ton U Capacity factor 0.8
Mill tailings U7% Ra, Th
Airborne Rn Th-230 100%, Ra 98%
22. Nuclear Fuel Cycle and Waste Generation
LLW 1,000 drums
~0.2 ton U
27.3 ton
26 ton U
27.5 ton
0.95 ton FP
0.27 ton Ac
0.24 ton Pu
26 ton
~ 0.5 ton U TRU/LLW
< 0.26 ton U
165 ton 0.95 ton FP
(0.3%U-235) 167 ton 0.27 ton Ac
100,000
ton ore
1 GWe, LWR, 1 year
Reprocessing scheme
0.2% U3O8 Thermal efficiency 0.325
~ 1 ton U
= 181 ton U Capacity factor 0.8
Mill tailings U7% Ra, Th
Airborne Rn Th-230 100%, Ra 98%
25. Repository Availability in US
• Repository capacity, 63,000 ton SF.
• Assume that:
– The present annual electricity generation (G = 70 GWy/year) is
maintained (no growth).
– The spent fuel generation per GWy is calculated by
W = 38,000 ton SF/1420 GWy = 27 ton/ GWy.
– The electricity generation C supported by this capacity:
C = 63000/27=2330 GWy
• The YM repository availability is obtained as
– C/G = 2330/70 = 33 years.
• 3 YM repositories will be necessary for one century.
26. Reprocessing of Spent Nuclear Fuel
Step 1: Decladding and Step 3: Extraction of U and Pu
Chopping by Tri Butyl Phosphate
Step 2: Dissolution into HNO3 (TBP)
Step 4: Pu Recovery from TBP
to Aqueous phase
32. Yucca Mountain
HUMBOLDT ELKO
COUNTY COUNTY
• Location: 100
WASHOE
COUNTY
miles NW of Las PERSHING
COUNTY
COUNTY
LANDER
EUREKA
COUNTY
Vegas in Nye CHURCHILL
COUNTY
County CARSON
CITY
LYON
STOREY
WHITE PINE
COUNTY
• Withdrawal Area:
DOUGLAS
NYE
MINERAL
230 sq. miles COUNTY
COUNTY
(150,000 acres) ESMERALDA
COUNTY NELLIS LINCOLN
• Distance: 14 miles
AIR FORCE COUNTY
RANGE
NV
from nearest year- TEST
SITE
CLARK
round population YUCCA COUNTY
MOUNTAIN INYO COUNTY
CALIFORNIA LAS
VEGAS
1 acre = 4,046.86 m2 = 1,224坪
33. Yucca Mountain
• Geology:
Composed of
ash tuff
deposited 10
million years ago
• Elevation: 4950
ft. at crest
• Climate:
receives less
than 7.5 inches
rain annually
• Resources:
none of
commercial
value
34. Yucca Mountain Repository
63,000 ton HM for CSNF
7,000 ton HM for Defense wastes
4,500 ton HM equivalent HLW
2,500 ton HM SNF (15 categories)
36. Three Types of Waste Packages
Number of packages
CSNF 7886
Co-disp 3564
DW
Naval 300
37. Program Key Milestones
• Design for License Application
– Completed December 1, 2007
• License Support Network Certification
– October 19, 2007 (two months earlier than schedule)
– Recertification: June 3, 2008
• Supplemental EIS
– Draft issued October 2007/hearings completed
• License Application
– Submitted to NRC on June 3, 2008
– Submittal included 208 references
– Will be “docketed” within 90 days (8/31) from the submittal
date
– Review by NRC will be completed within 3 years (2011).
38. Program Key Milestones (cont’d)
• Start Nevada Rail Construction - October 2009
– Delayed - Inadequate funding to proceed with design
• YM Construction Authorization - September 2011
– Depends on NRC decision
• Operating License Submittal - March 2013
– Predicated on funding and construction schedule
• Rail Line Operational - June 2014
– 2016 is achievable only if adequate funding is provided
• Begin Receipt - March 2017 (Best Achievable Date)
– Currently under evaluation due to FY 07 and 08 actual funding
shortfalls and expected near term funding limitations
– Firm date cannot be set until funding issue resolved
39. Waste Isolation Pilot Plant (WIPP),
Carlsbad, NM
• The world's first underground
repository licensed to permanently
dispose of transuranic (TRU) waste
left from the research and
production of nuclear weapons.
• After more than 20 years of
scientific study, public input, and
regulatory struggles, WIPP began
operations on March 26, 1999.
• Located in the remote Chihuahuan
Desert of Southeastern New Mexico • undertaken by DOE
• disposal rooms mined 2,150 feet • Waste from defense activities
underground in a 2,000-foot thick
salt formation that has been stable • Exempted from NRC regulation
for more than 200 million years. (EPA Certificate)
• Transuranic waste is currently • Bedded salt
stored at 23 locations nationwide. • 176,000 m3 Contact-Handled
• Over a 35 year period, WIPP is (CH)TRU,
expected to receive about 19,000 • 71,000 m3 Remote-Handled
shipments.
(RH)TRU
46. HLW Geologic Disposal Concept in Japan
Tunnel type
water-saturated granite
Vitrified waste
carbon-steel overpack
bentonite buffer
47. Functional requirements for Geologic Disposal
(OECD, 1989)
• The goal of final disposal is to protect human health and the
environment and to limit the burdens on future generations.
• The waste must not be released to the biosphere at concentrations
deemed to present an unacceptable hazard.
– Health risks and effects on the environment from waste disposal, at any
time in the future, shall be low and not greater than would be acceptable
today. The judgment of the acceptability of a disposal option shall be
based on radiological impacts irrespective of any national boundaries.
• The waste must be removed and isolated from the effects of human
activity or catastrophic natural events,
• the technology to implement disposal must be readily available as
well as achievable at a reasonable cost,
• The burden on future generations shall be limited by implementing
“at an appropriate time” a final disposal option which does not rely
for its safety on long-term institutional controls or remedial actions.
– in some countries, the retrieval of some types of disposed nuclear
wastes must be technologically and economically feasible, if so desired
by future generations,
• The processes which control safe performance of nuclear waste
disposal must be well-characterized by modeling.
• Sufficient, relevant data should be obtained and used in such
models to demonstrate predicted performance reliably.
48. Week 2 (7/1):
Performance assessment of
geologic disposal
Performance assessment
Can the environmental impact be
reduced by recycling?
50. Performance Assessment (PA) ,
Total System Performance Assessment (TSPA),
Safety Assessment
• PA: method for evaluation system, subsystem or
component performance
• TSPA: a system-level PA; subsystems and components
are linked into a single analysis
• Safety Assessment: if the result of TSPA is compared
with a safety standard and judgment is made, TSPA is
called safety assessment. (For YMR, TSPA = SA)
51. Annual Dose as the repository performance
measure
Biosphere
Biosphere
Annual dose,
dose conversion
BiCi mrem/yr
factor, Bi (mrem/yr)/(Ci/m3)
Repository
well
Geosphere
Plum Release,
Local nuclide
e of r Fi(t)
adion concentration, Ci(r,t)
u clide
s
Near field Far field
52. Barriers Evaluated in the Analysis
• Surficial soils and topography
• Unsaturated rock layers overlying the
repository
• Drip shield
• Waste package
• Spent fuel cladding
• Waste form / concentration limits
• Drift invert
• Unsaturated rock layers below repository
• Tuff and alluvial aquifers
53. Emplacement Drift
Emplacement drifts
5.5 m diameter
50-90 drifts, each ~ 1 km
long
56. Thermal Design Goals
Requirement Description
Tclad < 350°C Limit to prevent clad failure by increase in
creep rupture.
TDW < 200°C Prevents alteration of rock crystalline structure.
Tcenter < 96°C Pillar Drainage requirement, creates flow path
for water.
57. Natural System of Yucca Mountain
Repository located:
~1,000 ft. Below
Surface
~1,000 ft. Above
Water Table
Desert Environment
Unsaturated
Overburden
Unsaturated
Host Rock
Repository Horizon
Underlying
Unsaturated
Rock
Deep Water
Table
63. Summary of 10,000-year Results
(Draft Supplemental EIS, Oct. 2007)
• Total mean dose determined by contribution
from seismic scenario class
– Probability of damage to co-disposed waste packages
within 10,000 yr < 0.2
• Largest contribution to mean dose from 99Tc
• Magnitude of mean dose determined by
– Probability of events (seismic, igneous)
– Diffusion of radionuclides through cracks in waste
package outer barrier
• Total estimated peak mean annual dose for
10,000 years: 0.24 mrem/yr
– Well below regulatory limit of 15 mrem/yr
66. Summary of 1 million-year Results
(Draft Supplemental EIS, Oct. 2007)
• Total mean dose determined by occurrence of igneous
events, seismic damage and general corrosion
• Major contributors to dose are 99Tc, 129I, 239Pu, 242Pu,
226Ra, and 237Np
• Waste package outer barrier has primary influence on
releases of technetium and iodine
• Chemistry influences release of plutonium from waste
package
• Total estimated peak median annual dose for 1 million
years: 0.96 mrem/yr
– Well below proposed regulatory limit of 350 mrem/yr
67. Steps for TSPA
Detail models –– A
calculation typically
includes only a subset
of the repository system.
The calculation
produces predictions
that can be compared
with laboratory or field
data.
System models ––A
calculation produces
assessment of
regulatory performance
measures and the
uncertainty in the
performance measures
caused by the parameter
and model uncertainties
in the analysis.
70. Two Major Issues with Geologic
Disposal
• Repository Capacity for future nuclear-
power utilization
• Uncertainty and Confidence building in
long-term performance assessment
71. Types of uncertainty
• Aleatory:
– arises from an inherent randomness
– Stochastic, irreducible, Type A
• Epistemic:
– Derives from a lack of knowledge about the appropriate value to
use for a quantity that is assumed to have a fixed value.
– Subjective, reducible, Type B
• Examples
– Regulatory uncertainty (Epistemic)
– Conceptual-model uncertainty (Epistemic)
– Model parameter uncertainty (Epistemic)
– Stochastic uncertainty (Aleatory)
72. Regulatory uncertainty
• How can “repository performance” be
measured?
• How can a technical safety case be
justified within the regulatory framework?
– Safety criteria are themselves uncertain.
73. Congress, EPA, NRC, DOE
１９８０－８５ １９８５－９０ １９９０－９５ １９９５－００ ２０００－０５ ２００５－１０
EnPA
NWPA NWPAA 1992 VA Report for
Cong- 1982 1987 1996
Site Rec
2nd repository
By Energy Sec.
ress WIPPLWA 2002 2008-10
1992
40CFR 40CFR194 40CFR197
Part 191 WIPP DENIAL
1985 40CFR191 1998
EPA amended
2004
Mass of stored SF
（Standard） 40CFR191 1993 40CFR197 40CFR197
Exceeds YMR
YMR proposal
DENIAL capacity
2001 2005
1987 2014
10CFR60 10CFR60 10CFR60
Procedure Un-satu’d Pre-closure 10CFR63
NRC 1981 1985 1996 YMR
（Regulation）
10CFR60 10CFR60 2001
Technical NEPA
1983 1989
TSPA TSPA 10CFR963
1991 1995 2001
DOE 10CFR960
TSPA-VA License
（Guideline） 1984 TSPA Application
1998
1993 TSPA-SR And review
2001 2008-2011
74. Nuclear Waste Policy Act
(1982)
• Set the schedule for siting 2 repositories.
• EPA was charged with issuing generally
applicable limits on radioactivity releases
to the environment. (40CFR191)
• NRC was directed to develop regulations
and criteria for construction, operation,
and closure. (10CFR60)
• 1986: 9 sites ––> 5 sites ––> 3 sites
– Deaf Smith, Hanford, Yucca Mountain
75. NWPA Amendment Act (1987)
• Only Yucca Mountain be characterized to
evaluate its suitability as a repository.
• No site-specific work for a second
repository.
• Nullified the DOE proposal for MRS at the
Clinch River, TN.
• Site Characterization Plan for YM (1988)
76. 10CFR60 (1983)
• Waste-package lifetime > ~1000 yr
• Radionuclide fractional release rate from
EBS < 1/100,000 of its 1,000 yr inventory
• Groundwater travel time > 1,000 yr
• Overall performance: radionuclide release
to the accessible environment
(40CFR191).
77. 40CFR191 (1985)
• Disposal systems shall be designed so that
for 10,000 years the following limits will not
be exceeded at the accessible environment
with the likelihood of
– < 1 chance in 10 of exceeding the limit, and
– < 1 chance in 1000 of exceeding 10 times the
limit.
• Release limits are set on the basis of 1,000
MTHM.
– I-129: 100 Ci, Sr-90: 1000 Ci,
– Np-237: 100 Ci, Th-230: 10 Ci
78. Energy Policy Act (1992)
• Mandated a separate process for setting a
standard specifically for YMR.
• Required EPA to arrange for an analysis
by National Academy of Sciences (NAS).
– Can scientifically justifiable analyses of
repository behavior over many thousands of
years in the future be made?
• EPA reissued revised 40CFR191 in 1993.
79. Recommendations by
NAS Report (1995)
• Denial of release limits, i.e., 1000 incremental fatalities over 10,000
years
– The use of a standard that sets a limit on the risk to individuals of
adverse health effects from releases from the repository is
recommended.
– The critical-group approach should be used.
• Extension of time frame from 10,000 yr to a million yr
– The compliance with the standard measured at the time of peak risk,
within the limits imposed by the long-term stability of the geologic
environment, which is of the order of one million years.
• Denial of risk-based calculation of the adverse effect of human
intrusion into the repository
– The consequence of an intrusion should be calculated to assess the
resilience of the repository to intrusion.
80. 10 CFR Part 63 was rejected by the
federal appeals court due to a lawsuit
by Nevada State, July 2004.
• Post Closure Performance Assessment
– Computer simulation of repository performance over
10,000 years to:
• Consider geologic and engineered barriers
• Determine capabilities and time period to prevent or retards
movement of water and radionuclides
• Calculate radiological dose at 18 km (using lab and field
evidence for simulations)
– DOE must demonstrate using performance
assessment, that for 10,000 years the “reasonably,
maximally exposed individual” receives no more than
15 mrem per year from all pathways releases of
undisturbed YM disposal system.
82. Total System Performance Assessment Results
Total Mean and Median Annual Dose
(Draft Supplemental EIS, Oct. 2007)
83. Some thoughts about geologic
disposal
• Retrievability of wastes from a repository
– Final disposal vs. interim storage
• Fairness/Equity to future generations
– Who are “future generations”?
• Fairness/Equity to the local community around the
repository site
– Why Nevada, where no nuclear power plants exist?
• “Natural Barrier”
– May we contaminate rocks?
• Relationship with recycle/reprocessing
– Is recycle effective in improving repository performance?
84. Some thoughts about performance
assessment (PA)
• Performance assessment is:
– based on scientific facts and abstracted reality, and
– used as a tool for objective and optimized societal decision.
– a good way to communicate with the public?
• Annual dose as the performance measure for judgment
of long-term “environmental” safety.
– Should be understood as a “stylized” measure.
• The biosphere part of PA model is based on hypothetical
assumptions.
• This is actually not a measure for environmental safety, but
radiological safety.
– What kind of (technical) information needs to be provided by PA
for societal decision-making?
86. Nuclear Fuel Cycle
System parameters
d1, d2, p2, αf, γ1,γ2, … Solidification
Fuel cycle Matrix
M
System parameters
Reactor v, D, C*, ε, εp, d,
Uranium Process L, R, K, N, …
Loss
waste
Fuel Separation
Fabrication Process
Repository
Nuclear system
“IMPACT”
Environment
87. Generation of long-lived FPs in LWRs
(3410 MWt, 33,000 MWD/MT, 150-day cooling)
Half-lives fraction (%) nuclides
< 1 yr 4.8
1 to 10 yr 1.3 Ru-106, Sb-125, Cs-134, Pm-147,
Eu-154, Eu-155
10 to 30 yr 5.3 Kr-85 (11 yr), Sr-90 (29 yr), Cs-137 (30 yr)
30 to 100 yr 0.03 Sm-151
100 to 10,000 yr 0.0 N.A.
1E4 to 5E9 yr 6.6 Se-79, Zr-93, Tc-99 (2.1E5),
Pd-107, Sn-126, I-129(1.6E7)
Cs-135 (2.3E6)
> 5E9 yr 7.6 Rb-87, In-115, Ce-142, Nd-144,
Sm-147, Sm-148, Sm-149
Stable 78.1
Total 100.0
88. Generation of minor actinides (MA) per year
Nuclide 3410 MWt PWR
3 yr cooling 10 yr cooling
Np-237 57.9 % 41.3
Am-241 27.4 48.8*
Am-243 11.9 8.33
Cm-243 0.03 0.02
Cm-244 2.67 1.44
Cm-245 0.15 0.10
Total 100 100
*Am-241 increases due to beta decay of Pu-241.
89. Partitioning and Transmutation of HLW
• By destruction of long-lived radionuclides in HLW,
– Radioactivity and radiotoxicity of long-lived HLW are reduced
– risk for future recovery of nuclear weapons materials from a final
repository is reduced
– additional nuclear energy is gained by fissioning minor actinides
• For P-T,
– Reprocessing is a prerequisite
– Total radiological hazard arising from nuclear energy production
must be reduced.
– Secondary wastes from P-T processes must be taken into
account.
– Net energy production is desirable.
– System must be economical.
90. Processes for P-T
• Partitioning
– Conventional PUREX process + additional chemical partitioning process
ex. for Np, TRUEX has been developed.
– A process where separation of uranium and plutonium is combined with
recovery of elements to be transmuted.
ex. pyrochemical processing
• Transmutation
– Reactors
• LWR, FBR for electricity generation + actinide burners
• Th-U fuel cycle
– Accelerator
• high-energy proton spallation
(n, fission), (n, gamma), (n, 2n), (n, p) reactions
photo-nuclear reaction (gamma, n)
– Fusion reactor
92. Toxicity Index
λ i Ni
Toxicity index =Σ [m3]
i Ci,k
where
Ci,k : radioactivity concentration limit for nuclide i in medium k
(k = water or air) [Bq/m3],
Ni: the number of atoms of nuclide I
If more than one radionuclide is involved, a summation is performed over all
the isotopes present in the mixture.
Toxicity index is the volume of air or water with which the mixture of
radionuclides must be diluted so that breathing the air or drinking the water
will result in accumulation of radiation dose at a rate no greater than 0.5
rem/year.
94. Geologic disposal and P&T (1)
• 1970s
– Several disposal concepts were investigated and compared from
scientific viewpoints.
– Geologic repository concept
• 1977 Polvani Report (OECD/NEA)
• 1977 Stripa Project in Sweden
– Partitioning and Transmutation was proposed as an alternative
to geologic disposal
• 1980s
– Scientific studies to demonstrate the safety of geologic disposal
• OECD International Symposium on Safety assessment of
radioactive waste repositories, Paris 1989
– Denial of P&T concepts as an alternative to geologic disposal
• International Conference on Partitioning and Transmutation, Ispra,
1980
• UCBNE4176, Prof. T.H. Pigford, Paper presented at MIT
conference
• L. D. Ramspott, et al., “Impacts of New Developments in Partitioning
and Transmutation on the Disposal of High-Level Nuclear Waste in
a Mined Geologic Repository,” UCRL ID-109203, LLNL, March 1992.
95. UCBNE4176, 1990 by Pigford
(In the framework of 40CFR191)
1. By recycling actinides, the length of time that
needs to be considered for geologic disposal
would not decrease from 100,000 yr to 1000yr,
as claimed by P&T studies.
2. P&T is not necessary to satisfy 40CFR191
requirement for cumulative release of
radionuclides to the environment at 10,000yr.
3. To have significant reduction of actinide
inventory in a cycle, it will require more than
1000 yr of operation of P&T system to reach a
steady state. Even in such a case, reduction
better than 1/1000 is not possible.
96. Geologic disposal and P&T (2)
• 1990s
– Demonstration of geologic disposal concepts (more site specific studies)
– Shifting from natural barrier to engineered barriers
• TSPA studies in US for Yucca Mountain Repository
• SKB report, Sweden, 1991
• H3 and H12 reports, Japan, 1991, 1999
– P&T to improve repository performance
• EC/EU Framework
• France: SPIN project
• OECD/Japan OMEGA project
• US Liquid metal cooled actinide burner with pyroprocessing at ANL
• 2000s
– Sites for repositories announced
• YMR (US), Olkiluoto (Finland)
– Repository capacity issue has emerged.
– P&T and advanced fuel cycle
• Generation IV
• AFCI/GNEP
99. Effects of P&T in terms of
exposure dose rate (H12)
1.0E+00
1.0E-01
1.0E-02
Reference case
総線量 [μSv/y]
1.0E-03
1.0E-04
1.0E-05
99% actinide removed
1.0E-06
1.0E-07
1.0E+03 1.0E+04 1.0E+05 1.0E+06 1.0E+07 1.0E+08
Time after emplacement in repository, year
処分後の時間 [y]
Wakasugi, et al., Personal communications
100. Repository performance is
insensitive to P/T application
-- L. D. Ramspott, et al., “Impacts of New Developments in
Partitioning and Transmutation on the Disposal of High-Level
Nuclear Waste in a Mined Geologic Repository,” UCRL ID-
109203, LLNL, March 1992.
All other things being equal, less inventory means less
risk. However, the risk reduction benefits that P-T might
offer depend on the release scenario involved, and in
many cases, may not be as great as a 99.9% reduction in
actinide inventory might suggest.
101. So, can the environmental impact
be reduced by recycle?
• Yes, it can.
• However, whether reduction is meaningful or not
depends on
– combination of (a) waste form, (b) separation efficiency, and (c)
performance measures, suitable for geo-hydrological and
geochemical conditions of the repository.
• Environmental impact reduction would not necessarily be
the motivation for recycle;
– U resource utilization and proliferation resistance of the
repository could be more important.
• Environmental impacts from other parts of the fuel cycle
would directly be imposed on the current people, not
those in 10,000 years in future. Thus, comparison or
combination with other EI should be done carefully.
102. Week 3 (7/8):
Societal and ethical issues of
geologic disposal
Development of societal agreement
for geologic disposal
Ethics of geologic disposal
104. The Repository World
• Disposal in a geologic repository remains the preferred ultimate
solution, with or without reprocessing
• Much of the technical community has confidence in determining site
suitability
• A number of geologic media are being pursued
• Most programs have experienced substantial difficulties
• Siting remains the biggest hurdle
• Increasing recognition of multi-disciplinary nature
• Select ideas have become prominent, e.g. volunteer/veto,
retrievability, monitoring, phased management
• We will have storage for decades
105. Some Highlights and Lowlights
• National programs have been abandoned or siting
stopped
– France, U.K., Canada, Germany, Spain, Switzerland, U.S.A.
• National (re)reviews have been undertaken
– Canada, France, U.K.,…
• Schedules have been delayed
– Almost everywhere
• Some countries have moved forward and others have
restarted
– Finland, Sweden, U.S.A., France, Canada, Japan, U.K….
106. An (Optimistic) Current Snapshot
• Countries with candidate sites
– Finland, Sweden, U.S.A., France
• Countries with programs underway
– Canada, Belgium, Japan, U.K., Switzerland,…
• Countries “thinking about it”
– Spain, South Korea, China, India,…
• Countries starting out
– Argentina, Slovakia, Slovenia, South Africa,…
107. The Seaborn Panel Conclusions (1998)
--Canada--
• “From a technical perspective, safety of the AECL
concept has been on balance adequately demonstrated
for a conceptual stage of development. But from a social
perspective, it has not.”
• “As it stands, the AECL concept for deep geological
disposal has not been demonstrated to have broad
public support. The concept in its current form does not
have the required level of acceptability to be adopted as
Canada’s approach for managing nuclear fuel wastes.”
109. “Choosing a Way Forward”:
The Foundation
• “…this generation of citizens which has enjoyed
the benefits of nuclear energy has an obligation
to begin provision for managing that waste.”
• “…our obligation is to give them (succeeding
generations) a real choice and the opportunity
to shape their own decisions while at the same
time not imposing a burden which future
generations may not be able to manage.”
110. “Choosing a Way Forward”:
Some Key Recommendations
• Sequential decision-making and flexibility in the pace
and manner of implementation through “Adaptive
Phased Management”
• Ultimate centralized isolation in a deep geologic
repository
• Option for interim step of shallow underground storage
at the central site
• Program of continuous learning and R&D
• Long-term monitoring with potential for retrievability
• Seek an informed, willing community as host
111. What makes nuclear waste
management special?
• The technical challenge
– Performance over geological time
– “Proof” not possible
– Central role of “ologists”
• The institutional challenge
– The extraordinary time frame
– Siting
– Linkage to other agendas
– Values and ethics in conflict
– Political implications
– Nuclear stigma and fears
» But there are unique advantages…
112. Virtues of a Repository
• Passive
• Occurrences will be slow
• No inherent energy to release materials
• Retrievable
• Only a repository upon closure, when future
generations are comfortable
113. Some Key Enduring Features
• Core, stable goal
• Roles and responsibilities clear
• Clear, open, and transparent decision making process
• Respect for fairness and societal consent apparent
• Sequential decision-making and contingency planning
• Possibility of altering or reversing course
• Appropriate compensation
114. Some Potential Lessons Learned
• Take the necessary time - go slow in order to go fast
• Assign importance to the societal considerations as well
as the technical ones
• There are many ways to effectively engage the public
and key stakeholders
• Listening, respecting, and then responding can build trust
and even advocacy, particularly with local community
• Plan carefully and involve the right experts
• Be prepared to respond in real time to unexpected events
• Promise, then deliver, then do it again and again
116. three main virtues that have
withstood the test of time
• Humility
• Charity
• Veracity
117. Humility
Humility means you should treat yourself fully as one,
but not more than one.
• How does this apply when you have a group of
people (a corporation/government) that want to install
a nuclear plant/geologic repository?
• Is it considering that that group of people may have
different priorities than the group of people that they
are affecting by installing the plant?
• Is it the mentality that installing a power plant will
affect each person in their own situation differently?
• How do we reconcile these differences?
118. Charity
Charity means that you should treat others as fully one,
just the same as you treat yourself.
• Should the groups of people that run corporations
consider the groups of people that are affected by their
projects as equal to them?
• Should the people that are affected consider the
corporations equal?
• Who’s right is it to decide whether a project should go
forward? The people affected? Corporations?
Government?
119. Veracity
Veracity simply means telling the truth.
• It has already proven successful for some countries
to be completely open and honest with the people
who will be affected by power plant projects.
• It has been shown that when the company or
government that is planning the project takes the
time to sit down and discuss the plans with the
people, they are more receptive to the project.
• How important is it when it comes to these issues
for corporations? The government?
120. Consequentialism （帰結主義）
G.E.M. Anscombe, quot;Modern Moral Philosophyquot; (1958)
• Actions are evaluated based on the results they
achieve.
• A morally right action is one that produces a good
outcome, or consequence.
• The ethical action is the one that maximizes overall
good.
• Such theories are labeled teleological（目的論的）.
• A consequentialist may argue that lying is wrong
because of the negative consequences produced
by lying — though a consequentialist may allow
that certain foreseeable consequences might make
lying acceptable.
121. Utilitarianism（功利主義）
John Stuart Mill's essay Utilitarianism (1861)
• “the greatest good for the greatest
number”（最大多数の最大幸福）
• the moral worth of an action is solely
determined by its contribution to overall
utility, that is, its contribution to happiness
or pleasure as summed among all persons.
122. Deontology（義務論）
• Actions are evaluated based on the
motivation behind them.
• Deontology derives the rightness or
wrongness of an act from the character
of the act itself.
• A deontologist might argue that lying is
always wrong, regardless of any
potential quot;goodquot; that might come from
lying.
123. Kant’s three significant formulations
of the categorical imperative
(deontological)
• Act only according to that maxim by which you
can also will that it would become a universal
law.
• Act in such a way that you always treat humanity,
whether in your own person or in the person of
any other, never simply as a means, but always
at the same time as an end.
• Act as though you were, through your maxims, a
law-making member of a kingdom of ends.
125. ANS Code of Ethics
http://www.ans.org/about/coe/
1. We hold paramount the safety, health, and
welfare of the public and fellow workers, work
to protect the environment, and strive to
comply with the principles of sustainable
development in the performance of our
professional duties.
2. We will formally advise our employers, clients,
or any appropriate authority and, if warranted,
consider further disclosure, if and when we
perceive that pursuit of our professional duties
might have adverse consequences for the
present or future public and fellow worker
health and safety or the environment.
(veracity)
126. ANS Code of Ethics
http://www.ans.org/about/coe/
3. We act in accordance with all applicable laws
and these Practices, lend support to others
who strive to do likewise, and report violations
to appropriate authorities. (veracity, humility)
4. We perform only those services that we are
qualified by training or experience to perform,
and provide full disclosure of our qualifications.
(humility)
5. We present all data and claims, with their
bases, truthfully, and are honest and truthful in
all aspects of our professional activities. We
issue public statements and make
presentations on professional matters in an
objective and truthful manner. (veracity)
127. ANS Code of Ethics
http://www.ans.org/about/coe/
6. We continue our professional development
and maintain an ethical commitment
throughout our careers, encourage similar
actions by our colleagues, and provide
opportunities for the professional and ethical
training of those persons under our supervision.
7. We act in a professional and ethical manner
towards each employer or client and act as
faithful agents or trustees, disclosing nothing of
a proprietary nature concerning the business
affairs or technical processes of any present or
former client or employer without specific
consent, unless necessary to abide by other
provisions of this Code or applicable laws.
128. ANS Code of Ethics
http://www.ans.org/about/coe/
8. We disclose to affected parties, known or
potential conflicts of interest or other
circumstances, which might influence, or
appear to influence, our judgment or impair the
fairness or quality of our performance.
9. We treat all persons fairly. (Charity)
10. We build our professional reputation on the
merit of our services, do not compete unfairly
with others, and avoid injuring others, their
property, reputation, or employment.
11. We reject bribery and coercion in all their
forms.
129. ANS Code of Ethics
http://www.ans.org/about/coe/
12. We accept responsibility for our actions; are
open to and acknowledge criticism of our work;
offer honest criticism of the work of others;
properly credit the contributions of others; and
do not accept credit for work not our own.
(humility, veracity)
130. Ethics in Nuclear Engineering
• ANS Code of Ethics reflects a Deontological approach of
obeying a set of rules or principles. 9th point specifically
mirrors Kant’s Categorical Imperative.
• This contrasts, however, with the Consequentialism approach
which is taken in the matter of waste disposal.
• The potential for greater good for the greater number of
people is considered more important than the action, which
puts people at risk.
131. Yucca Mountain
• Yucca Mountain seemingly contradicts two tenets
of the ANS Code of Ethics:
– 1) welfare of the public, and
– 9) We treat all persons fairly
• is it fair that Nevada gets a site when they have no
nuclear power, and have been lied to in the past?
• Utilitarianism is the basis for ethics (greatest good
for the greatest #), but we still shouldn’t violate the
code of ethics, (#9)?
• In utilitarianistic consideration, is future generation
included?
132. Week 4 (7/15):
International aspects of nuclear
power utilization
(Introductory summary for nuclear
activities in India)
(Comparative discussions among
Japan, US, and India)
134. Topics to be Discussed in This Week
• As Asian economy expands rapidly, so
does energy demand in Asia.
– Why is this so important to us (or the US)?
• Nuclear Energy is an indispensable choice
for Asian countries.
– Are they ready for nuclear energy?
– How will it influence the world in the future?
– What is needed most there? And how can the
US respond to such needs?
139. Chinese Development Plan of Nuclear Power
Units to 2020
NPPs in operation and under construction
50000
Power Capacity (MWe)
45000 under construction
40000 in operation
35000
30000
25000 9,068MW
20000
7,860MW
1981-2007
15000 2004- 2014
10000
5000
0
19 1 1 1 1 2 2 2 2 2
8 2年 98 6年 99 0年 99 4年 99 8年 00 2年 00 6年 01 0年 01 4年 01 8年
26,000MW
2008- 2020
1.8% 4.0%
140. Scenarios for Total Installed Power
Capacity in India
(DAE-2004 and Planning Commission-2006 studies)
1600
1400
1200
1000
GWe
800
600
400
200
0
1990 2000 2010 2020 2030 2040 2050 2060
Year
DAE PC_GDP-Growth 8% PC_GDP-Growth 9%
141. Electricity growth rate – a scenario
Primary Electricity
Period
energy % annual % annual growth
2002-2022 growth
4.6 6.3
2022-2032 4.5 4.9
2032-2042 4.5 4.6
2042-2052 3.9 3.9
Per Capita Generation (kWh)
6000
5305
5000
3699
4000
3000 2454
2000 1620
1000
1000 613
0
2002 2012 2022 2032 2042 2052
Time period
142. GDP/capita vs. kWh/capita
US (2006)
($44,000, 13,000 kWh)
10000 Singapore
Brunei Japan
From 1999 to 2006
Hong Kong
South Korea
Malaysia
kWh/capita
China Thailand
1000
Philippines
India
Indonesia
Sri Lanka
100
100 1000 10000 100000
GDP/capita (US$)
143. By Increase in Energy
Consumption in Asia ....
• Global Environment
– CO2, SOx, NOx emissions
• Greenhouse effect, Acid Rain, etc.
• Competition for Limited Resources
• Nuclear Safety and Security
• International System
– If nuclear energy is developed on a large scale,
restructuring of international organizations for
safeguards will be necessary.
144. The Global Nuclear Energy Partnership Objectives are
Stated in The National Security Strategy
• The United States “will build the Global Nuclear Energy
Partnership to work with other nations to develop and
deploy advanced nuclear recycling and reactor
technologies.
• This initiative will help provide reliable, emission-free
energy with less of the waste burden of older
technologies and without making available separated
plutonium that could be used by rogue states or terrorists
for nuclear weapons.
• These new technologies will make possible a dramatic
expansion of safe, clean nuclear energy to help meet the
growing global energy demand.”
148. Discussion topics
• Developed vs. developing countries
– Resources
– Global environment
– Proliferation resistance – Access to technologies
• For whom? Why?
• Current vs. future generations
– Resources
– Global environment
• Nuclear vs. non-nuclear communities
– Public perception and communication
– Decision making processes
