jason t. harris, ph.d. idaho state university/natc radiological impact of commercial nuclear power...
TRANSCRIPT
Jason T. Harris, Ph.D.Idaho State University/NATC
Radiological Impact of Radiological Impact of Commercial Nuclear Power Commercial Nuclear Power Plant Releases: a 12-year Plant Releases: a 12-year
StudyStudy
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18th Annual RETS-REMP WorkshopJune 23-25, 2008
IntroductionIntroduction General Theory and MethodologyGeneral Theory and Methodology Radiological Impact of Effluent Radiological Impact of Effluent
ReleasesReleases Correlation between Effluent Correlation between Effluent
Releases and Electrical Releases and Electrical GenerationGeneration
REMP EvaluationREMP Evaluation Summary and Future WorkSummary and Future Work
Presentation Outline
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18th Annual RETS-REMP WorkshopJune 23-25, 2008
NPP Radiological ReleasesNPP Radiological Releases Small amounts of radiation released during normal
operating conditions Liquid effluents Gaseous effluents
Three categories of radioactive by-products produced Fission products
Over 300, many insignificant 85Kr, 131I, 133I, 133Xe, etc.
Neutron activation products 13N, 14C, 41Ar, 58Co, 59Fe, 60Co
Tritium (3H) Typically, radiological emissions insignificant to
population Effluent activities decreasing
Introduction (1/5)
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18th Annual RETS-REMP WorkshopJune 23-25, 2008
Introduction (2/5) Regulatory Criteria for ReleasesRegulatory Criteria for Releases
Radiation protection regulations based upon recommendations by ICRP and NCRP
U.S. regulations concerning nuclear power plant releasesUS
Regulatory Body
Regulation Explanation
USEPA 40 CFR 190(public doses)
1 mSv/y (0.1 rem/y) effective dose equivalent0.025 mSv/y (25 mrem/y) whole body dose0.075 mSv/y (75 mrem/y) thyroid dose0.025 mSv/y (25 mrem/y) all other organ dose
USNRC 10 CFR 20 1 mSv/y (0.1 rem/y) effective dose equivalent
10 CFR 50 NPP operations, technical specs. on effluents (Appendix I – numerical guides)
NUREG-0133 Radiological effluent technical specs.
Reg. Guide 1.109, 1.111, 1.112
Effluent and Solid Waste Release calcs.
NUREG-0016, 0017 BWR and PWR effluent calcs. (computer codes)
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18th Annual RETS-REMP WorkshopJune 23-25, 2008
REMPREMP NPPs required to monitor the radiological impact
of reactor operations on the environment and public (NEPA 1969 and FWPCA 1976)
Program Preoperational and operational components Trend and assess radiation exposure rates and conc. in
the environment Annual report submitted (and for releases)
Problem – decreased programs, decreased LLDs (positive results), public opinion, recent unexpected releases, and staff turnover
Introduction (3/5)
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18th Annual RETS-REMP WorkshopJune 23-25, 2008
Although effluent releases are well below regulatory limits (1%) it is important to continually monitor and scrutinize effluent release programs Effluent releases have a direct financial impact on nuclear liability
insurance premiums via the ERF (Engineering rating Factor) program. There is also an indirect financial impact. Performance information also plays an important part in the development of insurance risk profiles that support loss control strategies at each nuclear power plant facility.
As technology improves, MDAs will decrease and what may not have been there in the past, may now appear
Increased environmental findings at several operating and decommissioned plants
Public perception and confidence (Reputation!)
Introduction (4/5)
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18th Annual RETS-REMP WorkshopJune 23-25, 2008
Purpose of ResearchPurpose of Research Protection of public health and safety Study for entire U.S. commercial NPP industry Litigation protection, environmental pathway validity,
trending, projected impact (license renewals, new NPP construction, power-uprates), public perception
Compliance with National Environmental Policy Act of 1969, as amended and National Cancer Institute (1990 cancer study, NIH)
11 year study of all data for U.S. NRC, NSF, NPP utilities and UNSCEAR
ICRP 2007 Recommendations (protection of non-human species)
Comprehensive database development Recent NPP groundwater contamination and environmental
release events HypothesisHypothesis
Commercial nuclear power operations continues to pose little risk to the general public (radiological releases)
Introduction (5/5)
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18th Annual RETS-REMP WorkshopJune 23-25, 2008
U.S. NRC Dose ModelsU.S. NRC Dose Models
General Theory and Methodology (1/4)
Cip = concentration of radionuclide i in the media of pathway p, (Bq L-1, Bq kg-1, or Bq m-3 );Daipj = dose factor, specific to age group a, radionuclide i, pathway, and organ j (mSv pCi-1 );Raipj = annual dose to organ j or an individual of age group a, from nuclide i via pathway p mSv y-1 ); andUap = exposure time or intake rate (usage) associated with pathway p for age group a (hr y-1, L y-1 or kg y-1 ).
Generalized equation for calculating annual radiation dose via liquid effluent pathways (U.S. NRC Regulatory Guides 1.109 and 1.111)
aipjapipaipg DUCR
Obtained by summing potable water, aquatic food, shoreline deposit, andIrrigated food pathway doses
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18th Annual RETS-REMP WorkshopJune 23-25, 2008
U.S. NRC Dose ModelsU.S. NRC Dose Models
General Theory and Methodology (2/4)
D(r,θ) = total annual dose to an individual from airborne releases at location (r,θ) (mSv yr-1 );DT = annual total body dose from noble gas releases from free-standing stacks more than 80 meters high (mSv y-1 );D∞T = annual total body dose from all other noble gas releases (mSv y-
1 );DG = annual organ dose from external irradiation from radionuclides deposited onto the ground surface (mSv y-1 );DA = annual organ dose from inhalation of radionuclides in air (mSv y-
1 ); andDD = annual organ dose from ingestion of atmospherically released radionuclides in food (mSv y-1 );
Combined equation for calculating annual radiation dose via airborne effluent pathways (USNRC Regulatory Guides 1.109 and 1.111)
DAGTT DDDDDrD ),(
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18th Annual RETS-REMP WorkshopJune 23-25, 2008
UNSCEAR Dose ModelUNSCEAR Dose Model
General Theory and Methodology (3/4)
Generalized equation for calculating collective effective dose pathways (UNSCEAR 2000)
ii
iCE D
E
AD
Ai =activity of release category i (GBq);DCE = total collective effective dose (person-Sv GW-1 y-1);Di = collective dose for release category I (person Sv-1 PBq-1 ); andE = energy produced by the nuclear reactor (GW y-1 ).
Collective dose is divided according to release type (liquid or gaseous), radionuclide category (noble gases, tritium, C-14, iodine, particulate matter), and pathway (immersion, inhalation, ingestion, and external irradiation)
Model site and conditions
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18th Annual RETS-REMP WorkshopJune 23-25, 2008
Censored DataCensored Data
General Theory and Methodology (4/4)
Nuclear power plant releases are very small and may be below analytical detection limits (left censored data)
RETS and REMP reporting often include LLD and/or MDA values
Interpretation of results requires different statistical methods than for non-zero or non-LLD values
Because LLDs varied from one plant to another, substitution was used for less than values Mean and median calculated for industry REMP
study
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18th Annual RETS-REMP WorkshopJune 23-25, 2008
MethodsMethods Data from annual effluent release reports (1995-
2005) Gaseous effluents
Fission and activation products, total iodine, particulates, tritium
Liquid effluents Fission products, dissolved and entrained gases,
tritium, “other” radionuclides Trend analyses (Mann-Kendall) Dose calculations
Collective effective dose - UNSCEAR Theoretically maximally exposed individuals – U.S.
NRC
Radiological Impact of Effluent Releases (1/11)
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18th Annual RETS-REMP WorkshopJune 23-25, 2008
Radiological Impact of Effluent Releases (2/11)
1.E-01
1.E+00
1.E+01
1.E+02
1.E+03
1.E+04
1.E+05
1.E+06
1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006
Act
ivit
y (G
Bq
)
Year
F/A Gases Iodines
Tritium Particulates
1.0 × 101
1.0
1.0 × 104
1.0 × 105
1.0 × 106
1.0 × 103
1.0 × 102
1.0 × 10-1
Variation of radionuclide activity released in gaseous effluents from PWR plants.
ResultsResults F/A gases and
tritium released in highest quantities
Iodines and particulates several orders of magnitude lower
Singular events can skew entire industry data
PWRs (total) released in higher amounts due to greater number of plants
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18th Annual RETS-REMP WorkshopJune 23-25, 2008
Radiological Impact of Effluent Releases (3/11)
Variation of radionuclide activity released in gaseous effluents from BWR plants.
1.E-01
1.E+00
1.E+01
1.E+02
1.E+03
1.E+04
1.E+05
1.E+06
1.E+07
1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006
Act
ivit
y (G
Bq
)
Year
F/A Gases IodinesTritium Particulates
1.0 × 101
1.0
1.0 × 104
1.0 × 105
1.0 × 106
1.0 × 103
1.0 × 102
1.0 × 10-1
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18th Annual RETS-REMP WorkshopJune 23-25, 2008
Radiological Impact of Effluent Releases (4/11)
Variation of radionuclide activity released in liquid effluents from PWR and BWR plants
1.E-01
1.E+00
1.E+01
1.E+02
1.E+03
1.E+04
1.E+05
1.E+06
1.E+07
1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006
Act
ivit
y (G
Bq
)
Year
PWR TritiumPWR Other RadionuclidesBWR TritiumBWR Other Radionuclides
1.0 × 101
1.0
1.0 × 104
1.0 × 105
1.0 × 106
1.0 × 103
1.0 × 102
1.0 × 10-1
1.0 × 107
ResultsResults Tritium
released in highest quantities
Fairly level
Marked decline in BWR fission products and dissolved and entrained gases (fuel performance)
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18th Annual RETS-REMP WorkshopJune 23-25, 2008
Trend DetectionTrend Detection Mann-Kendall Non-Parametric Test Statistic
Results Gaseous PWR F/A Gases – decreasing trend Liquid PWR Tritium– increasing trend Gaseous BWR Tritium – increasing trend Liquid BWR Other Radionuclides – decreasing trend Gaseous Total F/A Gases – decreasing trend Liquid Total Other Radionuclides – increasing trend All other categories – no trend
Radiological Impact of Effluent Releases (5/11)
1
1 1
sgnn
k
n
kjkj xxS
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18th Annual RETS-REMP WorkshopJune 23-25, 2008
Radiological Impact of Effluent Releases (6/11)
Gaseous effluent release collective effective doses for PWR plants
1.0E-01
1.0E+00
1.0E+01
1.0E+02
1.0E+03
1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006
Col
lect
ive
effe
ctiv
e d
ose
(man
mS
v G
W-1y-1
)
Year
F/A Gases Iodines
Tritium Particulates
1.0
1.0 × 101
1.0 × 102
1.0 × 103
1.0 × 10-1
ResultsResults CEDs show
same pattern as activity releases
Variation in doses not as significant due to difference in collective doses
Even with small collective dose, tritium delivers highest CED due to volume released
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18th Annual RETS-REMP WorkshopJune 23-25, 2008
Radiological Impact of Effluent Releases (7/11)
Variation of radionuclide activity released in gaseous effluents from BWR plants.
1.0E+00
1.0E+01
1.0E+02
1.0E+03
1.0E+04
1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006
Col
lect
ive
effe
ctiv
e d
ose
(man
mS
v G
W-1 y
-1)
Year
F/A Gases IodinesTritium Particulates
1.0 × 101
1.0 × 102
1.0 × 103
1.0 × 104
1.0
ResultsResults CEDs show
same pattern as activity releases
Variation in doses not as significant due to difference in collective doses
F/A gases highest CED (less tritium released)
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18th Annual RETS-REMP WorkshopJune 23-25, 2008
Radiological Impact of Effluent Releases (8/11)
1.0E+00
1.0E+01
1.0E+02
1.0E+03
1.0E+04
1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006
Col
lect
ive
effe
ctiv
e d
ose
(per
son
mS
v G
W-1y-1
)
Year
PWR TritiumPWR Other RadionuclidesBWR TritiumBWR Other Radionuclides
1.0
1.0 × 102
1.0 × 104
1.0 × 101
1.0 × 103
Liquid effluent release collective effective doses for PWR and BWR plants
ResultsResults PWR liquids
give highest CEDs
Many BWRs do not release liquids
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18th Annual RETS-REMP WorkshopJune 23-25, 2008
Radiological Impact of Effluent Releases (9/11)
Year
Electrical EnergyProduced (GW)a
U.S.Population (× 104)b
Effective Dose (mSv)
Gaseous Releases Liquid Releases
TotalF/A Gases Total Iodine Tritium Particulates TritiumOther Radionuclides
199577.1 266,557 8.36 × 10-8 1.95 × 10-10 1.68 × 10-8 1.28 × 10-9 2.93 × 10-8 2.90 × 10-8 1.60 × 10-7
199677.3 269,667 7.79 × 10-8 2.75 × 10-10 1.31 × 10-8 1.10 × 10-9 3.18 × 10-8 2.89 × 10-8 1.53 × 10-7
199771.9 272,912 1.08 × 10-7 1.29 × 10-10 1.90 × 10-8 1.47 × 10-9 2.71 × 10-8 1.22 × 10-8 1.68 × 10-7
199874.9 276,115 1.38 × 10-8 2.80 × 10-10 1.46 × 10-8 2.66 × 10-9 2.68 × 10-8 1.37 × 10-8 7.19 × 10-8
199982.3 279,295 7.00 × 10-9 1.75 × 10-10 1.57 × 10-8 3.06 × 10-10 2.83 × 10-8 1.10 × 10-8 6.24 × 10-8
200085.2 282,402 7.98 × 10-9 1.80 × 10-10 1.48 × 10-8 1.08 × 10-9 3.05 × 10-8 1.07 × 10-8 6.53 × 10-8
200187.8 285,329 5.58 × 10-9 9.21 × 10-11 1.50 × 10-8 8.57 × 10-10 2.54 × 10-8 7.97 × 10-9 5.49 × 10-8
200288.6 288,173 8.42 × 10-9 1.95 × 10-10 1.73 × 10-8 6.62 × 10-10 2.70 × 10-8 1.96 × 10-8 7.32 × 10-8
200387.0 291,028 1.44 × 10-8 3.79 × 10-10 1.51 × 10-8 3.04 × 10-9 2.87 × 10-8 1.15 × 10-8 7.30 × 10-8
200488.1 293,907 6.94 × 10-9 2.67 × 10-10 1.39 × 10-8 2.07 × 10-10 2.64 × 10-8 6.38 × 10-9 5.42 × 10-8
2005
88.6 298,025 7.43 × 10-9 9.70 × 10-11 1.58 × 10-8 5.07 × 10-9 2.75 × 10-8 7.55 × 10-8 1.31 × 10-7
aU.S. NRC 2006a
bU.S. Census Bureau 2006
Average effective doses received by members of the public in the U.S. from commercial nuclear power plant radiological effluent releases.
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18th Annual RETS-REMP WorkshopJune 23-25, 2008
Radiological Impact of Effluent Releases (10/11)
1.0E-05
1.0E-04
1.0E-03
1.0E-02
1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007
Dos
e (m
Sv)
Year
PWR Gaseous Total Body Dose PWR Liquid Total Body Dose
PWR TOTAL Cumulative Dose BWR Gaseous Total Body Dose
BWR Liquid Total Body Dose BWR TOTAL Cumulative Dose
1.0 × 10-3
1.0 × 10-5
1.0 × 10-2
1.0 × 10-4
Mean annual total-body dose and cumulative dose commitments received by maximally exposed individual members of the public in the U.S. from PWR and BWR nuclear power plant radiological effluent releases
ResultsResults Cumulative
doses obtained by summing total body air dose, skin air dose, critical organ air dose, total body liquid dose, critical organ liquid dose, and site direct radiation
Total cumulative dose for PWRs and BWRs similar
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18th Annual RETS-REMP WorkshopJune 23-25, 2008
Radiological Impact of Effluent Releases (11/11)
Yearly total-body dose and cumulative dose commitments received by maximally exposed individual members of the public in the U.S. from commercial nuclear power plant radiological effluent releases
Year
Total body dose (mSv) Cumulative dose (mSv)
Liquid Gaseous
Mean ± S.D. (× 10-4) Total
Mean ± S.D. (× 10-4) Total Total Effluent
Mean ± S.D. (× 10-4) Total
Individual populationa
19986.24 ± 13.3 2.81 × 10-2 11.0 ± 22.4 3.96 × 10-2 6.77 × 10-2 40.8 ± 60.3 2.65 × 10-1
9.60 × 10-10
19997.37 ± 16.2 4.05 × 10-2 7.61 ± 18.1 3.50 × 10-2 7.55 × 10-2 43.6 ± 78.0 2.83 × 10-1
1.01 × 10-9
20007.42 ± 20.5 3.56 × 10-2 10.4 ± 23.4 4.57 × 10-2 8.13 × 10-2 38.1 ± 61.6 2.48 × 10-1
8.78 × 10-10
20016.68 ± 17.6 3.41 × 10-2 5.71 ± 16.3 2.46 × 10-2 5.87 × 10-2 46.5 ± 93.6 3.02 × 10-1
1.06 × 10-9
20024.42 ± 7.87 2.26 × 10-2 18.9 ± 44.4 8.72 × 10-2 1.10 × 10-1 52.9 ± 94.3 3.44 × 10-1
1.19 × 10-9
20033.97 ± 6.55 2.10 × 10-2 6.93 ± 20.9 2.84 × 10-2 4.94 × 10-2 41.9 ± 68.2 2.72 × 10-1
9.35 × 10-10
200410.1 ± 40.8 4.74 × 10-2 4.82 ± 14.3 1.78 × 10-2 6.52 × 10-2 47.0 ± 129 3.05 × 10-1
1.04 × 10-9
20054.37 ± 7.95 2.27 × 10-2 18.5 ± 58.6 7.97 × 10-2 1.02 × 10-1 32.7 ± 55.8 2.12 × 10-1
7.11 × 10-10
2006b
5.55 ± 7.80 2.33 × 10-2 13.1± 26.9 4.72 × 10-2 7.05 × 10-2 46.8 ± 91.8 3.04 × 10-1
1.01 × 10-9
a Obtained by dividing the total cumulative dose by the annual U.S. population (see Fig. 2 for population numbers)b 2006 U.S. population = 300,889 (× 104) (U.S. Census Bureau 2007)
Doses to the general public are insignificant compared to other radiation sources
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18th Annual RETS-REMP WorkshopJune 23-25, 2008
CorrelationCorrelation Determined to measure association between activity
released and electrical energy generated Specifically done to look at the affect of power-
uprates Release activities looked at for period of 3 years
before and after uprate took affect Normalized with capacity factor Importance – effluent dose models (UNSCEAR) and
trends normalized by plant type and electrical energy generated
Correlation between Release Activity and Electrical Generation (1/2)
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18th Annual RETS-REMP WorkshopJune 23-25, 2008
Pearson product-moment correlationPearson product-moment correlation
Statistic is defined as the sum of the products of the standard scores of the two measures divided by the degrees of freedom
Numerical range of +1 - -1 Results
No correlation (or pattern) between any release type and electrical generation (when compared alone)
Regardless of shared data Industry mean – no correlation
Correlation between Release Activity and Electrical Generation (2/2)
1N
zzr yx
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18th Annual RETS-REMP WorkshopJune 23-25, 2008
MethodsMethods Summary Data from annual REMP reports
Sample medium, type and number of analyses performed, LLD, mean and range of indicators, mean and range of control locations, and number of non-routine reports
Pathways and Analyses Direct radiation (TLD) Water - surface, ground, drinking (tritium, gamma) Sediments (gamma) Fish/Invertebrates (gamma) Food products, vegetation (gamma) Air particulates (gross beta) and Iodine Soil and grass (gamma) Non-routine samples (precipitation, storm water)
Number of analyses for study Sites average ~2000 y-1
Total – 1.4 x 106
REMP Evaluation (1/7)
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18th Annual RETS-REMP WorkshopJune 23-25, 2008
REMP Evaluation (2/7)
0
5
10
15
20
25
30
35
40
45
50
Wat
er (
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stio
n a
nd
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)
Fo
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k
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)
Per
cen
t Con
trib
uti
on o
f D
ose
Pathway Percent total cumulative dose contribution of various pathways resulting from U.S. nuclear power plant effluent releases.
ResultsResults Taken from
effluent doses given by each pathway
Direct radiation largest contributor (especially for BWR plants
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18th Annual RETS-REMP WorkshopJune 23-25, 2008
REMP Evaluation (3/7)
Ranking of environmental media based on potential radiation dose from BWR (above) and PWR (below) effluent releases..
Effluent Pathway/RadionuclideRelative Order of Importance
Gaseous Noble Gases
Gaseous Iodine
Gaseous Particulates
Gaseous Tritium
Liquid Tritium
Liquid Other Radionuclides
1 Direct radiation
Milk
2 Fish/invertebrates3 Drinking
water45 Particulate
submersionSubmersion
Effluent Pathway/RadionuclideRelative Order of Importance
Gaseous Noble Gases
Gaseous Iodine
Gaseous Particulates
Gaseous Tritium
Liquid Tritium
Liquid Other Radionuclides
1 Milk2 Direct
radiationDrinking water
Fish/invertebrates
34 Submersion5 Particulate
submersion
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18th Annual RETS-REMP WorkshopJune 23-25, 2008
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Pathway and Analysis
Percent of U.S. nuclear power plants sampling different REMP pathways and performing specific analyses (as of calendar year 2005)
REMP Evaluation (4/7)
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18th Annual RETS-REMP WorkshopJune 23-25, 2008
REMP Evaluation (5/7)
Number and type of non-routine results reported in REMP samples for U.S. commercial nuclear power plants. Only 0.0116% of all analyses were non-routine.
Year
Total Number ofnon-routine results
Number of Sites
Number of pathway and analysis for detected indicators
Surface water 3HCooling water gross beta/3H
Sediments gamma
Vegetation gamma
Air Iodine 131I
1995 15 7 8 2/1 4 0 01996 20 8 10 1 1 0 01997 14 6 6 1 1 0 01998 9 5 4 0 0 0 01999 17 8 8 0 0 0 12000 21 10 11 0 0 0 02001 20 9 11 0 0 0 02002 13 7 6 0 1 0 02003 8 4 4 0 0 0 02004 10 5 4 0 0 1 02005 16 8 8 0 0 0 0Total 163 77 80 5 7 1 1
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18th Annual RETS-REMP WorkshopJune 23-25, 2008
REMP Evaluation (6/7)
Direct radiation gamma exposure rates from plant ISFSIs
1.0E+00
1.0E+01
1.0E+02
1.0E+03
1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006
Gam
ma
exp
osu
re r
ate
(mR
qu
arte
r-1
)
Year
Calvert Cliffs Control Calvert Cliffs ISFSI Columbia ControlColumbia ISFSI North Anna Control North Anna ISFSIOconee Control Oconee ISFSI Peach Bottom ControlPeach Bottom ISFSI Prairie Island Control Prairie Island ISFSIPoint Beach Control Point Beach ISFSI San Onofre ControlSan Onofre ISFSI Surry Control Surry ISFSI
1.0 × 102
1.0 × 101
1.0 × 103
10
ResultsResults Direct
radiation from ISFSIs not statistically different from control locations
One plant gave exposure rates one order of magnitude higher
Emplacement of spent fuel is leading to higher exposure rates
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18th Annual RETS-REMP WorkshopJune 23-25, 2008
ConclusionsConclusions Summary Data
Detected radionuclides from background, weapons testing and plant produced
Use of controls and NRR isolate plant produced radionuclides
>99.9% of indicator results insignificant (compared to the controls)
Routine operation had no significant or measurable radiological impact to the environment
Releases well below regulatory limits (10 CFR 20 and 40 CFR 190)
REMP Evaluation (7/7)
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18th Annual RETS-REMP WorkshopJune 23-25, 2008
SummarySummary Comprehensive evaluation and analysis of U.S. commercial nuclear
power radiological effluent releases and REMP was conducted (1995-2005)
Effluent activities compiled and analyzed, showing trends Average CED and doses to maximally exposed individuals calculated
(continue to be very low compared to other sources of radiation and regulatory limits
No correlation found between effluent activity and electrical generation (when compared alone)
REMP evaluation showed no adverse radiological or environmental impact for the study period
Importance alone of database development can not be understated
Summary and Future Work (1/2)
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18th Annual RETS-REMP WorkshopJune 23-25, 2008
Future WorkFuture Work Total inventory still needed for radiological releases Standardization of reporting needed Standardization of LLDs More research in precipitation washout and other
pathways (particularly radionuclide concentration in ice/frost)
Continued industry analysis needed for providing accurate, scientifically bases information for the public
Summary and Future Work (2/2)
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18th Annual RETS-REMP WorkshopJune 23-25, 2008
Acknowledgements
Ph.D. Committee – (Drs. Cember, Miller, Sandison, Schweitzer, Stewart)
US NRC PDR Staff US NPP RETS-REMP staff RETS-REMP Workshop Steering Committee
Ken Sejkora, Ph.D. – Pilgrim Station, Richard Conatser – Calvert Cliffs
Greg Barley – Progress Energy, Steve Sandike –Indian Point
John Doroski – Millstone, Doug Wahl – Peach Bottom Richard Gilbert, Ph.D.
Funding provided by Purdue University, NATC, NPP utilities, EPRI and DoE OCRWM Fellowship Program
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18th Annual RETS-REMP WorkshopJune 23-25, 2008