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PNNL-18957
Recommended Updates to GALE Reactor Effluent Codes KJ Geelhood November 2009
PNNL-18957
Recommended Updates to GALE Reactor Effluent Codes
KJ Geelhood
November 2009
Prepared for
The U.S. Nuclear Regulatory Commission
Office of Nuclear Regulatory Research
Division of Risk Analysis
Washington, DC 20555-0001
under Contract DE-AC05-76RL01830
Pacific Northwest National Laboratory
Richland, Washington 99352
iii
Summary
This report describes work that Pacific Northwest National Laboratory (PNNL) is doing to assist U.S.
Nuclear Regulatory Commission (NRC) staff in their reviews of early site permit and combined license
applications for new nuclear power plants. This work focuses on assessing the potential consequences of
licensing actions for new reactor core designs. Potential updates are being considered for a suite of
models that are used to estimate the routine releases of radioactive materials to the environment from
pressurized water reactors and boiling water reactors. These models are the Gaseous and Liquid Effluents
(GALE) codes from Boiling-Water Reactors (BWR) and Pressurized-Water Reactors (PWR).
To direct the definition of what updates are needed to make the GALE codes applicable to facilities
using new reactor core designs, a sensitivity study was performed on the four GALE codes (Geelhood
et al. 2008)a. This study considered, based on selected representative nuclides, the sensitivity of hard-
wired parameters on the prediction of nuclide concentrations. In addition to the parameters identified in
the sensitivity study, the U.S. Nuclear Regulatory Commission also identified other parameters to be
examined and updated as necessary.
Recommendations are made for parameter and guidance updates to each of the GALE codes. The
parameters identified in the sensitivity study as having a significant impact on the output were
re-examined relative to modern reactor operations. Because facilities using new reactor core designs use
the same radwaste treatment processes, these operations at currently operating plants are applicable to the
radwaste operations at reactors using new core designs. A series of recommendations for making, or not
making, parameter changes in GALE codes are made. Each recommendation includes the reference to
the supporting data. When a change is recommended, the specifics of the change are defined. These
recommendations are the basis for new versions of the GALE codes that will be applicable to operations
at facilities using new reactor core designs.
a Geelhood KJ, MR Mitchell, and JG Droppo. 2008. Sensitivity Analysis of Hardwired Parameters in GALE Codes.
PNNL-18150, Pacific Northwest National Laboratory, Richland, Washington.
v
Acronyms, Initialisms, and Abbreviations
ANS American Nuclear Society
ANSI American National Standards Institute
BWR boiling water reactor
BWR-LE BWR GALE computer code for predicting liquid radioactive effluents
BWR-GE BWR GALE computer code for predicting gaseous radioactive effluents
Ci curie (unit of measurement of radioactivity)
DF decontamination factor
EPA U.S. Environmental Protection Agency
GALE computer code for estimating Gaseous and Liquid Effluents from Nuclear Electrical
Power Generation Reactors
GE gas effluent
HEPA high-efficiency particulate air (filter)
LE Liquid effluent
MW(t) megawatt thermal
NRC U.S. Nuclear Regulatory Commission
PNNL Pacific Northwest National Laboratory
PWR pressurized-water reactor
PWR-LE PWR GALE computer code for predicting liquid radioactive effluents
PWR-GE PWR GALE computer code for predicting gaseous radioactive effluents
vii
Contents
Summary ............................................................................................................................................... iii
Acronyms, Initialisms, and Abbreviations ............................................................................................ v
1.0 Introduction .................................................................................................................................. 1.1
2.0 GALE Parameter and Guidance Updates ..................................................................................... 2.1
2.1 Plant Capacity Factor ........................................................................................................... 2.2
2.1.1 Pressurized-Water Reactors ...................................................................................... 2.4
2.1.2 Boiling Water Reactors ............................................................................................. 2.4
2.2 Tritium Release .................................................................................................................... 2.4
2.2.1 Pressurized-Water Reactors ...................................................................................... 2.4
2.2.2 Boiling Water Reactors ............................................................................................. 2.5
2.3 Argon-41 Release ................................................................................................................. 2.6
2.3.1 Pressurized-Water Reactors ...................................................................................... 2.6
2.3.2 Boiling Water Reactors ............................................................................................. 2.7
2.4 Carbon-14 Release ............................................................................................................... 2.8
2.4.1 Pressurized-Water Reactors ...................................................................................... 2.9
2.4.2 Boiling Water Reactors ............................................................................................. 2.9
2.5 Adjustments to Liquid Release for Unexpected Release ..................................................... 2.10
2.5.1 Pressurized-Water Reactors ...................................................................................... 2.11
2.5.2 Boiling Water Reactors ............................................................................................. 2.13
2.6 Decontamination Factors for Demineralizers, Reverse Osmosis Units, Evaporators,
Centrifuges, and Filters ........................................................................................................ 2.14
2.6.1 Pressurized-Water Reactors ...................................................................................... 2.14
2.6.2 Boiling Water Reactors ............................................................................................. 2.16
2.7 Dynamic Adsorption Coefficients for Charcoal ................................................................... 2.17
2.7.1 Pressurized-Water Reactors ...................................................................................... 2.17
2.7.2 Boiling Water Reactors ............................................................................................. 2.18
2.8 Removal Efficiencies for HEPA Filters ............................................................................... 2.18
2.8.1 Pressurized-Water Reactors ...................................................................................... 2.18
2.8.2 Boiling-Water Reactors ............................................................................................. 2.18
2.9 Iodine Removal Efficiencies for Charcoal Adsorbers .......................................................... 2.19
2.9.1 Pressurized-Water Reactors ...................................................................................... 2.19
2.9.2 Boiling Water Reactors ............................................................................................. 2.20
3.0 Conclusions .................................................................................................................................. 3.1
4.0 References .................................................................................................................................... 4.1
viii
Figures
Figure 2.1. Industry-Wide Capacity Factor for All U.S. Nuclear Power Plants .................................. 2.3
Figure 2.2. Median Plant Capacity Factor for U.S. PWRs and U.S. BWRs ........................................ 2.3
Figure 2.3. PWR Tritium Release Data, Mean, and Confidence Interval ............................................ 2.5
Figure 2.4. BWR Tritium Release Data, Mean, and Confidence Interval ........................................... 2.6
Figure 2.5. PWR Argon-41 Release Data, Mean, and Confidence Interval ........................................ 2.7
Figure 2.6. BWR Argon-41 Release Data from Plants with Measureable Argon-41 Release,
Mean, and Confidence Interval ..................................................................................................... 2.8
Tables
Table 2.1. Parameters Examined in this Report ................................................................................... 2.1
Table 2.2. Reported Carbon-14 Release from PWRs .......................................................................... 2.9
Table 2.3. Reported Carbon-14 Release from BWRs .......................................................................... 2.10
Table 2.4. Unplanned Liquid Release of Gamma Emitters from PWR Plants .................................... 2.12
Table 2.5. Unplanned Liquid Release of Gamma Emitters from BWR Plants .................................... 2.13
Table 2.6. GALE Recommended Decontamination Factors for Various Nuclides in Various
PWR Demineralizers .................................................................................................................... 2.14
Table 2.7. GALE Recommended Decontamination Factors for Various Nuclides in Various PWR
Evaporators, Liquid Radwaste Filters, and Reverse Osmosis Units ............................................. 2.14
Table 2.8. Measured DFs for Mixed Bed Demineralizers ................................................................... 2.15
Table 2.9. GALE Recommended Decontamination Factors for Various Nuclides in Various
BWR Demineralizers .................................................................................................................... 2.16
Table 2.10. GALE Recommended Decontamination Factors for Various Nuclides in Various
BWR Evaporators, Liquid Radwaste Filters, and Reverse Osmosis Units ................................... 2.16
Table 2.11. GALE Recommended Dynamic Adsorption Coefficients for Krypton and Xenon in
Charcoal Delay System ................................................................................................................. 2.17
Table 2.12. Iodine Removal Efficiencies Recommended in Regulatory Guide 1.140 Rev. 1 ............. 2.19
Table 2.13. Iodine Removal Efficiencies Recommended in Regulatory Guide 1.140 Rev. 2 ............. 2.20
1.1
1.0 Introduction
This report describes work that Pacific Northwest National Laboratory (PNNL) is doing to assist U.S.
Nuclear Regulatory Commission (NRC) staff in their reviews of early site permit and license applications
for new nuclear power plants. This work focuses on assessing the potential consequences of licensing
actions for new reactor core designs. Potential updates are being considered for a suite of models that are
used to estimate the routine releases of radioactive materials to the environment from pressurized water
reactors and boiling water reactors. These models are the Gaseous and Liquid Effluents (GALE) codes
from Boiling-Water Reactors (BWR) and Pressurized-Water Reactors (PWR).
New nuclear power generating facilities have been proposed for operation in the United States using
new reactor core designs. The objective of this effort is to define what updates are needed to the GALE
codes to make them applicable for use in the licensing process for these new facilities.
Making the GALE codes applicable to the proposed new nuclear power generating facilities requires
consideration of 1) updates to the GALE source codes and 2) updates to the guidance for using these
codes. The GALE updates for the new core designs are to be based a combination of a review of how the
new designs may change routine reactor radwaste operations and on more recent reactor operating
experience than was used for developing the original GALE codes.
Several aspects of the GALE source codes need to be considered. In terms of the formulations used
in the source codes, Geelhood et al. (2008) concluded the radwaste treatment technologies treated in the
GALE source codes will be appropriate for the proposed new reactors. However, it was also
recommended that new versions of the GALE with modern coding structure be created. The “spaghetti
structure” of the original GALE versions makes code verification and maintenance especially difficult.
The parameters used to characterize the liquid and gas effluents are a combination of input and hard-
wired parameters. Changes in input parameters can be documented as changes in the user guidance for
doing GALE simulations. The parameters hard wired in each of the GALE source codes may also need to
be updated. A sensitivity study was performed on the hard-wired parameters in four GALE codes
(Geelhood et al. 2008) to help direct the definition of which of these parameters may need to be updated.
The results of a review of parameter values for applications to facilities using new reactor core designs
are provided as follows.
2.1
2.0 GALE Parameter and Guidance Updates
A review of recent reactor operational experience and the design details for proposed new nuclear
power generating facilities is used as a basis for recommendations for updates to the GALE source codes
and their user guidance.
The sensitivity study performed for the four GALE codes (Geelhood et al. 2008) provides a basis for
evaluating which parameters may need to be updated. The sensitivity study considered, based on selected
representative nuclides, the sensitivity of hard-wired parameters on the prediction of nuclide
concentrations. In addition to the parameters identified in the sensitivity study, NRC also identified other
parameters to be examined and updated as necessary. Because facilities using new reactor core designs
use the same radwaste treatment processes, these operations at currently operating plants are applicable to
the radwaste operations at reactors using new core designs.
The first column in Table 2.1 lists the parameters in the GALE codes that were examined. The
second column has the section number where each parameter is discussed.
Table 2.1. Parameters Examined in this Report
Parameter
Section of this
Report
Plant capacity factor 2.1
Tritium release 2.2
Argon-41 release 2.3
Carbon-14 release 2.4
Adjustment to liquid release for unexpected release 2.5
Decontamination factors for demineralizers, reverse osmosis units
evaporators, centrifuges, and filters
2.6
Dynamic adsorption coefficients for charcoal 2.7
Removal efficiencies for HEPA filters 2.8
Iodine removal efficiencies for charcoal adsorbers 2.9
Several parameters examined in this report were updated on the basis of taking an average value of a
random sampling from reactor operations over the past 8 years. The approach used was to collect a
number of measurements and calculate the mean value using Equation 1 and the standard deviation using
Equation 2.
n
x
x
n
i
i
1 Equation 1
2.2
1
)( 2
1
n
xx
s
n
i
i
Equation 2
Where: x = mean of sample population
s = standard deviation of the population
xi = individual measurements
n = number of measurements
In order to determine if the number of measurements used to calculate the mean value was sufficient,
a 95% confidence interval was constructed around the mean value using a Student t-distribution. This
was done using Equation 3.
n
stxCI
)*)((
Equation 3
Where: CI = 95% confidence interval about the mean
x = mean of sample population
t* = value on t-distribution table for 95% confidence level and the number of samples taken
s = standard deviation of the population
n = number of measurements
If the confidence interval is small relative to the mean, then the calculated mean value can be used. If
the confidence interval remained large and more data were available, the process would be repeated with
more data. Once an appropriately small confidence interval was found or all the data was included, the
upper bound of the confidence level was used as the value recommended for GALE as a conservative
estimate of the mean.
2.1 Plant Capacity Factor
The plant capacity factor defines what fraction of full capacity of the facility occurs during long-term
operation of that facility. The current versions of the PWR GALE and BWR GALE codes use a
hardwired value of 80% for plant capacity factor.
Nuclear-industry-wide capacity factors have been compiled by the Energy Information
Administration of the U.S. Department of Energy and are tabulated in the Annual Energy Review (AER
2009). Figure 2.1 shows these capacity factors since 1973. The mean capacity factor between 2000 and
2008 was 89.8% with a standard deviation of 1.4%. These data may warrant increasing the plant capacity
factor used in the updated GALE codes.
2.3
Figure 2.1. Industry-Wide Capacity Factor for All U.S. Nuclear Power Plants
Figure 2.2 shows median plant capacity factor for three-year intervals compiled separately for BWRs
and PWRs by Blake (2009). Blake discusses using the median statistic rather than the mean to reduce the
impact of the outage of Browns Ferry-1. For the period from 2000 to 2008, the yearly mean value of the
median plant capacity is 89.6% for U.S. PWRs and is 90.6% for all U.S. BWRs. Therefore, it is
recommended that the plant capacity factor used in the updated PWR GALE and BWR GALE codes be
increased to 90%.
Figure 2.2. Median Plant Capacity Factor for U.S. PWRs and U.S. BWRs
2.4
2.1.1 Pressurized-Water Reactors
For the period from 2000 to 2008, Blake (2009) calculates the yearly mean value of the median plant
capacity to be 89.6% for U.S. PWRs. Using data reported by Blake (2009) for 69 individual U.S. PWRs,
the mean plant capacity factor is 89.8%, and the standard deviation is 5.3% during the three-year period
from 2006 through 2008. Therefore, it is recommended that the plant capacity factor used in the updated
PWR GALE codes be increased to 90%.
The original version of PWR GALE uses a plant capacity factor to determine the yearly tritium
release per MW(t). However, the tritium release value in the new version of PWR GALE will be updated
based on actual plant measurements as discussed in Section 2.2 and will not require a calculation
involving plant capacity factor.
2.1.2 Boiling Water Reactors
For the period from 2000 to 2008, Blake (2009) calculates the yearly mean value of the median plant
capacity to be 90.6% for U.S. BWRs. Using data reported by Blake (2009) for 25 individual U.S. BWRs,
the mean plant capacity factor is 89.2%, and the standard deviation is 8.5% during the three-year period
from 2006 through 2008. As covered by Blake (2009), the extended (22 year) outage of Browns Ferry-1
did not end until almost half of this period had elapsed. Compensating for the influence of the extended
Browns Ferry-1 outage results in a mean plant capacity factor for this period of 90.6% with a standard
deviation of 3.8% for the remaining 34 U.S. BWRs. Therefore, it is recommended that the plant capacity
factor used in the updated BWR GALE codes be increased to 90%.
In the BWR GALE codes, iodine release rates and the carbon-14 release rates are a function of plant
capacity factor and are hard wired into the code. Iodine release rates from various buildings are given in
terms of Ci/yr/ Ci/g separately for normal operation and extended shutdown. Since the recommended
plant capacity factor is 90%, the revised iodine release rates for normal operation should be increased by
multiplying by 1.125 (90%/80%), and the revised iodine release rates for extended shutdown should be
decreased by multiplying by 0.5 (10%/20%). The recommendation that the carbon-14 release rate be
increased to use a 90% plant capacity factor in the formula that calculates carbon-14 production will be
discussed further in Section 2.4.
2.2 Tritium Release
Tritium release defines the expected rate of tritium release for long-term operation of a nuclear power
generating facility.
2.2.1 Pressurized-Water Reactors
The current version of PWR GALE uses a value of 0.4 Ci/yr/MW(t) for tritium release. This tritium
is partitioned between liquid and gaseous effluents by assigning 1 Ci/ml of primary reactor coolant to
liquid release up to 90% of the total release. The remaining tritium is released as a gaseous effluent. The
value 1 Ci/ml is specified in ANS 18.1 (ANS 1984).
Surveys were performed on the tritium release from randomly selected reactors between the years
2000 and 2007. A total of 76 reactor-years were surveyed, and a mean tritium release value of
2.5
0.243±0.025 Ci/yr/MW(t) was calculated with a 95% confidence level. The data, mean, and confidence
interval are shown in Figure 2.3. Based on the upper bound average from this survey, it is recommended
that the tritium release from PWR be changed to 0.27 Ci/yr/MW(t). The partitioning between gaseous
and liquid effluents will remain the same as the most recent ANS 18.1 standard (ANS 1999), which still
specifies 1 Ci/ml of tritium in the primary coolant.
Figure 2.3. PWR Tritium Release Data, Mean, and Confidence Interval
2.2.2 Boiling Water Reactors
The current version of BWR GALE uses a value of 0.03 Ci/yr/MW(t) for tritium release. This tritium
is partitioned between liquid and gaseous effluents by assigning 50% of the tritium to liquid release and
50% of the tritium to gaseous release.
Surveys were performed on the tritium release from randomly selected reactors between the years
2000 and 2008. A total of 71 reactor-years were surveyed, and a mean tritium release value of
0.0299±0.0068 Ci/yr/MW(t) was calculated with a 95% confidence level. The data, mean, and
confidence interval are shown in Figure 2.4. Based on this survey, it is recommended that the tritium
release from BWR remain the same at 0.03 Ci/yr/MW(t). The partitioning between gaseous and liquid
effluents was examined for those plants with both gaseous and liquid release, and an average value of
65% gas and 35% liquid was calculated. There was significant scatter in these ratios. As such, it is
recommended that the ratio of 50% liquid and 50% gaseous effluents be retained.
2.6
Figure 2.4. BWR Tritium Release Data, Mean, and Confidence Interval (previous value and sample
mean are identical)
2.3 Argon-41 Release
Argon-41 release defines the expected rate of argon-41 gas release for long-term operation of a
nuclear power generating facility.
2.3.1 Pressurized-Water Reactors
The current version of PWR GALE uses a value of 34 Ci/yr for argon-41 release.
Surveys were performed on the argon-41 release from randomly selected reactors between the years
2000 and 2007. A total of 76 reactor-years were surveyed, and a mean argon-41 release value of
3.471±1.9904 Ci/yr was calculated with a 95% confidence level. The data, mean, and confidence interval
are shown in Figure 2.5. Based on this survey, it is recommended that the argon-41 release from PWR be
changed to the upper bound of the confidence level of the average value, or 6 Ci/yr.
2.7
Figure 2.5. PWR Argon-41 Release Data, Mean, and Confidence Interval
2.3.2 Boiling Water Reactors
The current version of BWR GALE uses a combination of several sources for the argon-41 release.
The BWR GALE code assumes 15 Ci/yr is released from the drywell and includes this in the argon-41
released from the containment building. The BWR GALE code also assumes that 40 Ci/s (1262 Ci/yr)
is input to the main condenser offgas treatment downstream of the air ejectors. A holdup time for
argon-41 is calculated assuming dynamic adsorption coefficients for argon-41 in a charcoal delay system
of 6.4 cm³/g at ambient conditions and 16 cm³/g for chilled conditions. The argon-41 remaining after this
holdup is released from the air ejector.
The 15 Ci/yr of argon-41 from the drywell is based on a measured neutron flux in the drywell
interacting with natural argon-40 in the air and assuming 24 purges per year. It is not likely that the
neutron flux in the drywell has changed, and 24 purges per year approaches the value of an open drywell,
thus is probably conservative for this analysis
It was determined that the dynamic adsorption coefficients measured when the charcoal delay beds
were installed are still applicable for modern reactors. Section 2.7 provides more discussion on this topic.
Therefore, it is recommended that the assumed dynamic adsorption coefficients for argon-41 be retained
in GALE.
The 1262 Ci/yr input to the main condenser is based on air inleakage containing argon-40 at or
downstream of the main condenser. This argon-40 is activated in the reactor coolant to argon-41 and
2.8
released through the main condenser offgas treatment system. The value selected was an upper bound of
only several measurements made and represents a conservative upper bound. No additional
measurements have been made, but this value probably still represents a conservative upper bound.
Plants were surveyed for argon-41 release. Of the 71 reactor-years surveyed, 33 of those years had
measurable argon-41 release. The mean of these data was 11.1±7.0 Ci/yr with a 95% confidence level.
For the sample BWR case, GALE predicted an argon-41 release of 38 Ci/yr, which bounds this mean
value. The current data, mean, confidence interval, and previous GALE prediction for the sample case
are shown in Figure 2.6.
Given a further lack of specific data on argon-41 or relevant system upgrades, it is recommended that
the current methodology for calculating argon-41 release from BWRs be retained in GALE.
Figure 2.6. BWR Argon-41 Release Data from Plants with Measureable Argon-41 Release, Mean, and
Confidence Interval (GALE Calculation for the Sample Case also is shown)
2.4 Carbon-14 Release
Carbon-14 release defines the expected rate of carbon-14 release for long-term operation of a nuclear
power generating facility.
2.9
2.4.1 Pressurized-Water Reactors
The current version of PWR GALE uses a value of 7.3 Ci/yr for carbon-14 release based on
measurements from seven reactors between 1975 and 1978.
NRC does not require licensees to report carbon-14 in their annual radioactive release reports.
Because of this, it is not possible to compile a large data set of carbon-14 release values as with the
tritium (hydrogen-3) and argon-41. A search of literature published since the time of the last survey was
performed to determine if more recent data would indicate a different carbon-14 release.
An EPRI report (Vance et al. 1995) presented data from two U.S. and six German PWRs in 1984 and
1985 that had an average carbon-14 release of 5.9 Ci/yr. Another source (Yim et al. 2006) referenced an
EPA study in 1981 that found the release to be about 5 Ci/yr. These data are shown in Table 2.2.
Table 2.2. Reported Carbon-14 Release from PWRs
Reactor Carbon-14 release, Ci/yr
E(a)
9.264
F(a)
5.684
H(b)
3.01
I(b)
8.19
J(b)
1.242
K(b)
4.3692
L(b)
5.985
M(b)
9.49
Average 5.9
EPA study 5
(a) U.S. reactor.
(b) German reactor.
It is recommended that the value in the PWR GALE be decreased from 7.3 Ci/yr to 5.9 Ci/yr based on
average values from the most recent surveys. This value also compares well with value from the
aforementioned EPA study.
2.4.2 Boiling Water Reactors
The current version of BWR GALE uses a value of 9.5 Ci/yr for carbon-14 release based on the
assumption that all the carbon-14 produced in the reactor coolant will be released and the formula for
carbon-14 production provided in Equation 4.
Q = Noσoφmtps Equation 4
Where: Q = carbon-14 release rate, Ci/yr
No = 1.3x1022
atoms O-17/kg in water
2.10
σo = 2.4x10-25
cm-2
thermal cross section for O-17
φ = 3x1013
n/cm²s average thermal flux
m = 3.9x104 kg water in reactor core
t = 3.15x107 s/yr
p = 0.8, plant capacity factor
s = 1.03x10-22
Ci/atom carbon-14
Based on these values, a release rate for carbon-14 of 9.5 Ci/yr can be calculated.
As discussed in Section 2.1.2, the plant capacity factor should be increased to 0.9. If this is done, a
release rate for carbon-14 of 10.7 Ci/yr is calculated.
In order to confirm that this calculated value is reasonable, a literature search of recent publications
was performed. An EPRI report (Vance et al. 1995) presented data from one U.S. and three German
BWRs in 1984 and 1985 that had an average carbon-14 release of 10.7 Ci/yr. Another source (Yim et al.
2006) referred to an EPA study from 1981 that found the release to be about 9 Ci/yr. This source also
stated that in a BWR, all the produced carbon-14 is released from the condenser steam jet air ejector.
These data are shown in Table 2.3. These references confirm the calculated value of 10.7 Ci/yr, as well
as the assumption that all the carbon-14 produced will be released.
Table 2.3. Reported Carbon-14 Release from BWRs
Reactor Carbon-14 release, Ci/yr
3 10.18
7 10.05
8 12.397
9 10.34
Average 10.7
EPA study 9
Calculated value 10.7
Based on the updated calculation, it is recommended that the value in the BWR GALE be increased
from 9.5 Ci/yr to 10.7 Ci/yr. Recent surveys confirm that this value is reasonable.
2.5 Adjustments to Liquid Release for Unexpected Release
Adjustment factors are used in GALE code to account for unexpected releases during normal
operations.
2.11
2.5.1 Pressurized-Water Reactors
The current version of PWR GALE uses a value of 0.16 Ci/yr to adjust the liquid release of all
nuclides except for tritium. This value of 0.16 Ci/yr is partitioned to the nuclides based on their relative
distribution calculated from other sources.
Surveys were performed on the unexpected release from all the U.S. operating PWRs for up to five
years between the years 2000 and 2008. Palo Verde units 1, 2, and 3 were excluded from this survey
because they have no liquid release. In addition, Point Beach units 1 and 2 were excluded as no mention
was made of unexpected release in the annual release reports for these plants. A total of 320 reactor-years
worth of data were examined; the average unexpected liquid release value for all nuclides other than
tritium was 1.6x10-4
Ci/yr. The data are shown in Table 2.4
Based on this survey, it is recommended that release from unexpected liquid releases be changed
from 0.16 Ci/yr to 1.6x10-4
Ci/yr.
2.12
Table 2.4. Unplanned Liquid Release of Gamma Emitters from PWR Plants
Reactor Date Release, Ci Reactor Date Release, Ci Reactor Date Release, Ci Reactor Date Release, Ci
Watts Bar 2007 0 Vogtle-2 2008 0 Calvert Cliffs 1 2007 0.00000084 Waterford 3 2008 0
2006 0.00000492 2007 0 2005 0 2007 0
2005 0 2006 0 2004 0 2006 0
2004 0 2005 0 2003 0 2005 0
2003 0 2004 0 2002 0 2004 0
2002 0 Comanche Peak 1 2008 0 Calvert Cliffs 2 2007 0.00000084 Braidwood-1 2008 0
2001 0 2007 0 2005 0 2007 0
2000 0 2006 0 2004 0 2006 0.0002685
Indian Point 2 2004 0 2005 0 2003 0 2005 0
2005 0.0005025 2004 0 2002 0 2004 0
2006 0.0002831 Comanche Peak 2 2008 0 Gina 2008 0 Braidwood-2 2008 0
2007 0.000035 2007 0 2007 0 2007 0
Indian Point 3 2004 0 2006 0 2005 0 2006 0.0002685
2005 0.0005025 2005 0 2004 0 2005 0
2006 0.0002831 2004 0 2003 0 2004 0
2007 0.000035 Sequoyah-1 2005 0 Millstone-2 2007 0 Byron-1 2008 0
Kewaunee 2007 0 2004 0 2006 0 2007 0
2006 0 2003 0 2005 0 2006 0
2005 0 2002 0 2004 0 2005 0
2004 0 2001 0 2003 0.000296 2004 0
2003 0 Sequoyah-2 2005 0 Millstone-3 2007 0 Byron-2 2008 0
2002 0 2004 0 2006 0 2007 0
2001 0 2003 0 2005 0 2006 0
2000 0 2002 0 2004 0 2005 0
Crystal River 3 2007 0 2001 0 2003 0 2004 0
2006 0 South Texas 1 2008 0 North Anna-1 2006 0 Beaver Valley-1 2008 0
2005 0 2007 0 2005 0 2007 0
2004 0 2006 0 2004 0 2006 0
2003 0 2005 0 2003 0.0178 2005 0.000163
2002 1.60E-06 2004 0 2002 0 2004 0.0003645
2001 4.40E-06 South Texas 2 2008 0 North Anna-2 2006 0 Beaver Valley-2 2008 0
2000 0 2007 0 2005 0 2007 0
San Onofre 2 2007 0 2006 0 2004 0 2006 0
2006 0 2005 0 2003 0.0178 2005 0.000163
2005 0 2004 0 2002 0 2004 0.0003645
2004 0 Virgil Summer 2008 0 Surry-1 2008 0 Davis Besse 2007 0
2003 0 2007 0 2007 0 2006 0
San Onofre 3 2007 0 2006 0 2006 0 2004 0
2006 0 Shearon Harris 2008 0 2005 0 2003 0
2005 0 2007 0 2004 0 2002 0
2004 0 2006 0 Surry-2 2008 0 St. Lucie-1 2008 0
2003 0 2005 0 2007 0 2007 0
Wolf Creek 2007 0 2004 1.55E-05 2006 0 2006 0
2006 0 Robinson-2 2008 0 2005 0 2005 0
2005 0 2007 0 2004 0 2004 8.77E-03
2004 0 2006 0 McGuire-1 2008 0 St. Lucie-2 2008 0
2003 0 2005 0 2007 0 2007 0
Catawba 1 2007 0 2004 0 2006 0 2006 0
2006 0 Diablo Canyon 1 2008 0 2005 0 2005 0
2005 0 2007 0 2004 0 2004 0
2003 0 2006 0 McGuire-2 2008 0 Turkey Point-3 2008 0
2002 0 2005 0 2007 0 2007 0
Catawba 2 2007 0 2004 0 2006 0 2006 0
2006 0 Diablo Canyon 2 2008 0 2005 0 2005 0
2005 0 2007 0 2004 0 2004 0
2003 0 2006 0 Oconee-1 2008 0 Turkey Point-4 2008 0
2003 0 2005 0 2007 0 2007 0
Salem-1 2008 0 2004 0 2006 0 2006 0
2007 0 Fort Calhoun 2005 0 2005 0 2005 0
2006 0 2004 0 2004 0 2004 0
2005 0 Prairie Island 1 2008 0 Oconee-2 2008 0 Seabrook 2007 0
2004 0 2007 0 2007 0 2005 0
Salem-2 2008 0 2006 0 2006 0 2001 0
2007 0 2004 0 2005 0 2000 0
2006 0 2003 0 2004 0 Donald Cook -1 2008 0.000000056
2005 0 Prairie Island 2 2008 0 Oconee-3 2008 0 2007 0
2004 0 2007 0 2007 0 2006 0
Farley-1 2008 0 2006 0 2006 0 2005 0
2007 0 2004 0 2005 0 2004 0
2006 0 2003 0 2004 0 Donald Cook -2 2008 0.000000056
2005 0 Callaway 2007 0 ANO-1 2006 0 2007 0
2004 0 2006 0 2005 0 2006 0
Farley-2 2008 0 2005 9.28E-04 2004 0 2005 0
2007 0 2004 1.82E-03 2002 0 2004 0
2006 0 TMI-1 2008 0 2001 0 Palisades 2007 0
2005 8.81E-08 2007 0 ANO-2 2006 0 2006 0
2004 0 2006 0 2005 0 2005 0
Vogtle-1 2008 0 2004 0 2004 0 2004 0
2007 0 2001 0 2002 0 2003 0
2006 0 2001 0
2005 0
2004 0
2.13
2.5.2 Boiling Water Reactors
The current version of BWR GALE uses a value of 0.1 Ci/yr to adjust the liquid release of all
nuclides except for tritium. This value of 0.1 Ci/yr is partitioned to the nuclides based on their relative
distribution calculated from other sources.
Surveys were performed on the unexpected release from all the U.S. operating BWRs for up to five
years between the years 2000 and 2008. Columbia, Duane Arnold, Clinton, and Fermi-2 were excluded
from this survey because they had no liquid release. In addition, Peach Bottom units 2 and 3 were
excluded as the release from unexpected release was not separately quantified from the normal release in
the annual release reports for these plants. A total of 147 reactor-years were examined; the average
unexpected liquid release value for all nuclides other than tritium was 0.014 Ci/yr. The data are shown in
Table 2.5.
Table 2.5. Unplanned Liquid Release of Gamma Emitters from BWR Plants
Reactor Date Release, Ci Reactor Date Release, Ci Reactor Date Release, Ci Reactor Date Release, Ci
Grand Gulf 2007 0 Browns Ferry 1 2007 0.0617 Nine Mile Point 2 2008 0 Limerick-1 2008 0.0000418
2006 0.955 2005 0.0375 2007 0 2007 0
2005 0 2004 0 2006 0 2006 0.00092325
2004 0 2003 0.837 2005 0 2005 0
2003 0 2002 0 2004 0 2004 0
2002 0 Browns Ferry 2 2007 0 FitzPatrick 2008 0 Limerick-2 2008 0.0000418
2001 0 2005 0 2006 0 2007 0
2000 0 2004 0 2005 0 2006 0.00092325
Dresden 2 2008 0 2003 0 2004 0 2005 0
2007 0 2002 0 2003 0 2004 0
2006 0 Browns Ferry 3 2007 0 Pilgrim 2008 0 Perry-1 2008 0
2005 0.13 2005 0 2007 0 2007 0
2004 0.00000566 2004 0 2006 0 2006 0
Dresden 3 2008 0 2003 0 2004 0 2005 0
2007 0 2002 0 Vermont Yankee 2008 0 2004 0
2006 0 Susquehanna 1 2008 0 2007 0 Cooper 2006 0
2005 0 2007 0 2006 0 2005 0
2004 0 2006 0 2005 0 2004 0
Quad Cities 1 2007 0 2004 0 2004 0 2003 0
2006 0.0001047 2003 0 River Bend 2008 0 2001 0
2005 0.00205 Susquehanna 2 2008 0 2007 0 Montecello 2008 0
2004 0.00444 2007 0 2006 0 2007 0.0000237
2003 0.0562 2006 0 2004 0 2006 0
Quad Cities 2 2007 0 2004 0 2002 0 2005 0
2006 0 2003 0 LaSalle-1 2008 0 2004 0.00000742
2005 0 Oyster Creek 2008 0 2007 0 Hope Creek 2008 0
2004 0 2007 0 2006 0 2007 0
2003 0 2006 0.000141 2005 0 2006 0
Brunswick 1 2007 0 2005 0 2004 0 2005 0
2006 0 2004 0 LaSalle-2 2008 0 2004 0
2005 0 Nine Mile Point 1 2008 0 2007 0 Hatch-1 2008 0
2004 0 2007 0 2006 0 2007 0
2003 0 2006 0 2005 0 2006 0
Brunswick 2 2007 0 2005 0 2004 0 2005 0
2006 0 2004 0 2004 0.0000065
2005 0 Hatch-2 2008 0
2004 0 2007 0
2003 0 2006 0
2005 0
2004 0
Based on this survey, it is recommended that release from unexpected liquid releases be changed
from 0.1 Ci/yr to 0.014 Ci/yr.
2.14
2.6 Decontamination Factors for Demineralizers, Reverse Osmosis Units, Evaporators, Centrifuges, and Filters
The GALE code uses decontamination factors to define the expected performance of radwaste
systems during long-term operation of a nuclear power generating facility.
2.6.1 Pressurized-Water Reactors
For all the liquid radwaste systems in PWR GALE, except the primary coolant demineralizer and the
condensate demineralizer, the user is required to input the expected decontamination factor (DF). For the
primary coolant demineralizer, GALE assumes DFs of 2 for cesium and rubidium and 10 for all other
nuclides. For the condensate demineralizer, GALE assumes DFs of 2 for cesium and rubidium, 100 for
anions, and 50 for other nuclides.
The GALE input document provides recommended values to use for all other liquid radwaste
systems. These values are shown in Tables 2.6 and 2.7.
Table 2.6. GALE Recommended Decontamination Factors for Various Nuclides in Various
PWR Demineralizers
Anion Cesium, Rubidium Other Nuclides
Mixed bed purification systems (LiBO3) 100(a)
2(a)
50(a)
10(b)
Boron recycle system 10 2 10
Evaporator condensate (H+OH
-) 5 1 2
(b) 10
Radwaste (H+OH
-) 10²(10) 2(10) 10²(10)
Steam Generator Blowdown 10²(10) 10(10) 10²(10)
Cation bed (H+) (any system) 1(1) 10(10) 10(10)
Anion bed (OH-) (any system) 10²(10) 1(1) 1(1)
Powdex (any system) 10(c)
(10) 2(c)
(10) 10(c)
(10)
(a) Hard wired for Condensate Demineralizer.
(b) Differences between GALE and ANS 55.6-1993 are shown in bold italic.
(c) Hard wired for Primary Coolant Demineralizer.
Table 2.7. GALE Recommended Decontamination Factors for Various Nuclides in Various PWR
Evaporators, Liquid Radwaste Filters, and Reverse Osmosis Units
All Nuclides Except Iodine Iodine
Miscellaneous radwaste
evaporators
10³ 10²
Boric acid evaporators 10³ 10²
Separate evaporator for detergent
wastes
10² 10²
Liquid radwaste filters 1 1
Reverse osmosis units 10(30 for laundry) 10(30 for laundry)
2.15
The latest ANS standard on liquid radioactive waste processing (ANS-55.6-1993 R 2007) contains a
table of DFs for various evaporators, demineralizers, and reverse osmosis units. The values in this
standard were compared with the values in Tables 2.6 and 2.7. In all cases except for two, the
recommendations in GALE were identical to those in ANS-55.6-1993 R (2007). The values that are
different are shown in bold italic font (b) in Table 2.6 after the recommended value.
ANS-55.6-1993 R (2007) does not provide recommended DFs for liquid radwaste filters. One
reference, Mandler et al. (1981), provided 216 measurements at three PWR plants that gave an average
DF of 1.56 for liquid radwaste filters. The primary purpose of a filter is not to reduce the activity of the
wastewater, but to reduce solids input to other systems (ANS-55.6-1993 R 2007). Based on this, it is
appropriate and slightly conservative to retain the current GALE recommended DF of 1.0 for liquid
radwaste filters.
In order to confirm the DFs that are hard wired in GALE as noted in Table 2.6, a brief literature
search was performed for these types of demineralizers. For the primary coolant demineralizer, the DFs
from the Powdex row are used. A recent evaluation of the Powdex process (Salem and LaTerra 1999)
stated that Powdex processes could remove more than 90% of all metals from the condensate (DF=10).
This confirms the DF assumed for all nuclides except cesium and rubidium. This evaluation (Salem and
LaTerra 1999) also stated that the Powdex process could remove 50% (DF=2) to 90% (DF=10) of various
iron oxides. Given that cesium and rubidium are highly reactive with water and will probably exist in the
water as oxides, a DF of 2 for these elements seems reasonable.
For the condensate demineralizer, the DFs from the mixed bed row are used. One reference (Mandler
et al. 1981) provides measured DFs from mixed beds for various nuclides taken from four PWRs. These
measurements are shown in Table 2.8. The average values found in these measurements are 1191 for
anions, 6.9 for cesium, and 96.4 for all others. This comparison demonstrates the DFs that GALE and
ANS-55.6-1993 R (2007) use are conservative; however, it is not clear that this would justify increasing
the DFs as individual values at or below the GALE recommended values were measured.
Table 2.8. Measured DFs for Mixed Bed Demineralizers (Mandler et al. 1981)
Measurement Anion Cesium Other
1 2600 1.3 69
2 3600 1.3 95
3 100 1.2 13
4 18 1.2 20
5 380 1.0 40
6 450 1.0 40
7 36 15
8 35 6.7
9 0.95 680
10 0.95 170
11 1.2 6.7
12 1.2 1.3
Average: 1191 6.9 96.4
GALE Value 100 2 50
ANS-55.6-1993 Value 100 2 10
2.16
2.6.2 Boiling Water Reactors
For all the liquid radwaste systems in BWR GALE, except the condensate demineralizer, the user is
required to input the expected DF. For the condensate demineralizer, GALE assumes DFs of 2 for cesium
and rubidium and 10 for other nuclides.
The GALE input document provides recommended values to use for all other liquid radwaste
systems. These values are shown in Tables 2.9 and 2.10.
Table 2.9. GALE Recommended Decontamination Factors for Various Nuclides in Various
BWR Demineralizers
Anion Cesium, Rubidium Other Nuclides
Mixed bed (H+OH
-)
Reactor coolant
10
2
10
Condensate 10(a)
2(a)
10(a)
Clean waste 10²(10) 10(10) 10²(10)
Dirty waste (floor drains) 10²(10) 2(10) 10²(10)
Cation bed (H+)
Dirty waste
1(1)
10(10)
10²(10) 10(10)(b)
Powdex (any system) 10(10) 2(10) 10(10)
(a) Hard wired for Condensate Demineralizer.
(b) Differences between GALE and ANS 55.6-1993 are shown in bold italic.
Table 2.10. GALE Recommended Decontamination Factors for Various Nuclides in Various BWR
Evaporators, Liquid Radwaste Filters, and Reverse Osmosis Units
All Nuclides Except Anions Anions
Miscellaneous radwaste
evaporator
104 10
3(a) 10
3 10
2(a)
Separate evaporator for detergent
wastes
102
102
Liquid radwaste filters 1 1
Reverse osmosis units 10(30 for laundry) 10(30 for laundry)
(a) Differences between GALE and ANS 55.6-1993 are shown in bold italic.
The latest ANS standard on liquid radioactive waste processing (ANS-55.6-1993 R 2007) contains a
table of DFs for various evaporators, demineralizers, and reverse osmosis units. The values in this
standard were compared with the values in Tables 2.9 and 2.10. In all cases except for two, the
recommendations in GALE were identical to those in ANS-55.6-1993 R (2007). The values that are
different are shown in bold italic font in Tables 2.9 and 2.10, following their recommended value.
ANS-55.6-1993 R (2007) does not provide recommended DFs for liquid radwaste filters. Based on
the recent data with PWR liquid radwaste filters (previously discussed) and the fact that the primary
purpose of a filter is not to reduce the activity of the wastewater but to reduce solids input to other
2.17
systems (ANS-55.6-1993 R 2007), it is appropriate and slightly conservative to retain the current GALE
recommended DF of 1.0 for liquid radwaste filters.
It is recommended that he following changes be made to the GALE recommended DFs:
PWR mixed bed purification systems (LiBO3) DF for other nuclides should change from 50 to 10.
PWR evaporator condensate (H+OH
-) DF for cesium, rubidium should change from 1 to 2.
BWR cation bed (H+) dirty waste DF for other nuclides should change from 100(10) to 10(10).
BWR miscellaneous radwaste evaporator DFs should change from 103 for anions and 10
4 for other
nuclides to 102 for anions and 10
3 for other nuclides.
In addition, since the DFs for PWR mixed bed purification systems are hard wired in GALE for the
condensate demineralizer, the PWR GALE code should be changed to use a DF for other nuclides of 10
rather than 50.
2.7 Dynamic Adsorption Coefficients for Charcoal
The GALE codes use dynamic adsorption coefficients to define the expected performance charcoal
filter systems during long-term operation of a nuclear power generating facility.
2.7.1 Pressurized-Water Reactors
In the PWR GALE code, the user must specify the holdup time for fission gases stripped from the
primary coolant. There are several different holdup systems, described below, with the input required for
PWR GALE:
1. Pressurized storage tanks—calculate holdup times and fill time using the equations provided in the
PWR GALE manual.
2. Charcoal delay systems—calculate holdup times using the equations provided in the PWR GALE
manual and the table of dynamic absorption coefficients provided in the PWR GALE manual.
3. Cover gas recycle system—assumes a 90-day holdup time
The Table 2.11 shows the dynamic adsorption coefficients that are recommended for a charcoal delay
system.
Table 2.11. GALE Recommended Dynamic Adsorption Coefficients for Krypton (Kr) and Xenon (Xe)
in Charcoal Delay System
Operating 77°F
Dew Point 45°F
Operating 77°F
Dew Point 0°F
Operating 77°F
Dew Point -40°F
Operating 0°F
Dew Point -20°F
Krypton 18.5 25 70 105
Xenon 330.0 440 1160 2410
In an e-mail conversation with Charles Myers, president of Columbus, Ohio-based NCS Corp., a
longtime industry leader in the testing and servicing of safety-related HVAC systems, he shared that little
2.18
work has been done in the field of activated charcoal that would improve on these dynamic adsorption
coefficients since the original systems were installed. Several more recent measurements (Sun et al.
1994) of dynamic adsorption coefficients show reasonable agreement with the data used in the GALE
derivation. Based on this, it is recommended that the table of recommended dynamic adsorption
coefficients shown in Table 2.11 be retained in the user input guidelines.
2.7.2 Boiling Water Reactors
In the BWR GALE code, the user must specify the xenon and krypton dynamic adsorption
coefficients for the charcoal delay system in the condenser air ejector offgas treatment system.
The Table 2.11 shows the dynamic adsorption coefficients that are recommended for a charcoal delay
system.
The charcoal delay systems in a BWR are the same as those in a PWR. Therefore, similar to the
PWR recommendation, it is recommended that the table of recommended dynamic adsorption coefficients
shown in Table 2.11 be retained in the user input guidelines.
2.8 Removal Efficiencies for HEPA Filters
The GALE code uses removal efficiencies to define the expected performance of HEPA filter systems
during long-term operation of a nuclear power generating facility.
2.8.1 Pressurized-Water Reactors
In the PWR GALE code, the user is required to enter the removal efficiency for any HEPA filters in
use in the waste gas system and fuel handling and auxiliary buildings. In addition, removal efficiencies
for HEPA filters in use in the containment internal cleanup system, high volume purge, and low volume
purges must be specified.
The PWR GALE manual suggests a removal efficiency of 99% on Regulatory Guide 1.140 rev. 1
(NRC 1979). This regulatory guide was updated in 2001 (NRC 2001), but the updated version still
recommends a removal efficiency of 99%.
Based on this, the recommendation for user input if HEPA filters are used should stay at 99%. If a
manufacturer is able to provide information that its HEPA filters will remove more than this, the utility
can input a greater removal rate and reference the manufacturer’s data.
2.8.2 Boiling-Water Reactors
In the BWR GALE code, the user is required to enter the removal efficiency for any HEPA filters in
use in the containment, turbine, auxiliary, and radwaste buildings.
The BWR GALE manual suggests a removal efficiency of 99% on Regulatory Guide 1.140 rev. 1
(NRC 1979). This regulatory guide was updated in 2001 (NRC 2001), but the updated version still
recommends a removal efficiency of 99%.
2.19
Based on this, the recommendation for user input if HEPA filters are used should stay at 99%. If a
manufacturer is able to provide information that its HEPA filters will remove more than this, the utility
can input a greater removal rate and reference the manufacturer’s data.
2.9 Iodine Removal Efficiencies for Charcoal Adsorbers
The GALE code uses removal efficiencies to define the expected performance of iodine removal
systems during long-term operation of a nuclear power generating facility.
2.9.1 Pressurized-Water Reactors
In the PWR GALE code, the user is required to enter the iodine removal efficiency for any charcoal
adsorbers in use in the fuel handling and auxiliary buildings. In addition, removal efficiencies for
charcoal adsorbers in use in the containment internal cleanup system, high volume purge, and low volume
purges must be specified.
The PWR GALE manual provides a table of removal efficiencies based on Regulatory Guide 1.140
rev. 1 (NRC 1979). The 1979 table is repeated here as Table 2.12. This regulatory guide and its
corresponding table have been updated, and the user should use the updated table from Regulatory
Guide 1.140 rev. 2 (NRC 2001). The 2001 version of the table is repeated as Table 2.13.
It is recommended that the PWR GALE user input be updated to reference the removal efficiencies in
Table 2.13.
Table 2.12. Iodine Removal Efficiencies Recommended in Regulatory Guide 1.140 Rev. 1 (1979)
Activated Carbon Bed Depth Removal Efficiencies for Radioiodine
2 inches. Air filtration systems designed to operate
inside reactor containment
90%
2 inches. Air filtration systems designed to operate
outside reactor containment and relative humidity is
controlled at 70%
70%
4 inches. Air filtration systems designed to operate
outside reactor containment and relative humidity is
controlled at 70%
90%
6 inches. Air filtration systems designed to operate
outside reactor containment and relative humidity is
controlled at 70%
99%
2.20
2.9.2 Boiling Water Reactors
In the BWR GALE code, the user is required to enter the removal efficiency for any charcoal
adsorbers that are in use in the containment, turbine, auxiliary, and radwaste buildings.
The BWR GALE manual provides a table of removal efficiencies based on Regulatory Guide 1.140
rev. 1 (NRC 1979) . The 1979 table is repeated here as Table 2.12. This regulatory guide and its
corresponding table have been updated, and the user should use the updated table from Regulatory
Guide 1.140 rev. 2 (NRC 2001). This table is repeated as Table 2.13.
It is recommended that the BWR GALE user input instructions be updated to reference the removal
efficiencies in Table 2.13.
Table 2.13. Iodine Removal Efficiencies Recommended in Regulatory Guide 1.140 Rev. 2 (2001)
Activated Carbon Total
Bed Depth
Maximum Assigned Activated
Carbon Decontamination
Efficiencies
Methyl Iodine Penetration Acceptance
Criterion for Representative Sample
2 inches Elemental iodine
Organic iodine
95%
95%
Penetration ≤ 5% when tested in
accordance with ASTM D-3803-1989
4 inches or greater Elemental iodine
Organic iodine
99%
99%
Penetration ≤ 1% when tested in
accordance with ASTM D-3803-1989
3.1
3.0 Conclusions
Code and guidance updates needed in each of the GALE codes are identified. The supporting data for
each of the recommended parameter changes listed below are given in the main text. These changes are
to be the basis for new versions of the GALE codes that will be applicable to operations at facilities using
new reactor core designs.
The following changes to the GALE codes are proposed in this document:
Plant capacity factor should be increased from 0.8 to 0.9 (80% to 90%)
BWR iodine release rates from various buildings during normal operations should be increased by
multiplying by 1.125
BWR iodine release rates from various buildings during extended shutdown should be decreased by
multiplying by 0.5
PWR tritium release rate should be decreased from 0.4 Ci/yr/MW(t) to 0.27 Ci/yr/MW(t)
PWR argon-41 release rate should be decreased from 34 Ci/yr to 6 Ci/yr
PWR carbon-14 release rate should be decreased from 7.3 Ci/yr to 5.9 Ci/yr
BWR carbon-14 release rate should be increased from 9.5 Ci/yr to 10.7 Ci/yr
PWR unexpected release rate should be decreased from 0.16 Ci/yr to 1.6x10-4
Ci/yr
BWR unexpected release rate should be decreased from 0.1 Ci/yr to 0.014 Ci/yr
PWR condensate demineralizer DF for other nuclides should be changed from 50 to 10
In addition, the following changes to the GALE user input instructions are proposed in this document:
For both PWR and BWR GALE, change the recommended values for iodine removal efficiencies
from those in Table 2.12 (1979) to those in Table 2.13 (2001)
PWR mixed bed purification systems (LiBO3) DF for other nuclides should change from 50 to 10
PWR evaporator condensate (H+OH
-) DF for cesium, rubidium should change from 1 to 2
BWR cation bed (H+) dirty waste DF for other nuclides should change from 100(10) to 10(10)
BWR miscellaneous radwaste evaporator DFs should change from 103 for anions and 10
4 for other
nuclides to 102 for anions and 10
3 for other nuclides
4.1
4.0 References
ANS 18.1-1984. December 1984. American Nuclear Society Standard Radioactive Source Term for
Normal Operation of Light Water Reactors. American Nuclear Society, Illinois.
ANS 18.1-1999. September 1999. American Nuclear Society Standard Radioactive Source Term for
Normal Operation of Light Water Reactors. American Nuclear Society, Illinois.
ANS-55.6-1993. 2007R. American Nuclear Society Standard for Liquid Radioactive Waste Processing
System for Light Water Reactor Plants. American Nuclear Society, Illinois.
Blake EM. May 2009. “U.S. capacity factors: Can older reactors keep up the pace?” Nuclear News, 29-
33.
EIA - Energy Information Administration. 2009. Annual Energy Review 2008. DOE/EIA-0384(2008).
Energy Information Administration, U.S. Department of Energy, Washington, D.C.
Geelhood KJ, MR Mitchell, and JG Droppo. 2008. Sensitivity Analysis of Hardwired Parameters in
GALE Codes. PNNL-18150, Pacific Northwest National Laboratory, Richland, Washington.
Mandler JW, AC Stalker, ST Croney, CV McIsacc, GA Soli, JK Hartwell, LS Loret, BG Motes, TE Cox,
DW Akers, NK Bihl, SW Duce, JW Tkachyk, CA Pelletier, and PG Voileque. 1981. In-Plant Source
Term Measurements at Four PWR’s. NUREG/CR-1992, Nuclear Regulatory Commission,
Washington, D.C.
NRC - U.S. Nuclear Regulatory Commission. 2001. Design, Inspection, and Testing Criteria for Air
Filtration and Adsorption Units of Normal Atmosphere Cleanup Systems in Light-Water-Cooled Nuclear
Power Plants. Regulatory Guide 1.140 Rev. 2, U.S. Nuclear Regulatory Commission, Washington D.C.
NRC - U.S. Nuclear Regulatory Commission. 1979. Design, Testing, and Maintenance Criteria for
Normal Ventilation Exhaust System Air Filtration and Adsorption Units of Light-Water-Cooled Nuclear
Power Plants. Regulatory Guide 1.140 Rev. 1, U.S. Nuclear Regulatory Commission, Washington, D.C.
Salem E and T LaTerra. 1999. Half a Century of Condensate Polishing. Graver Water Systems, Inc.,
Cranford, New Jersey.
Sun CL, JC Chen, YW Yu, HC Ha, CS Lu, and TY Lee. 1994. “Dynamic Adsorption Properties of Kr
and Xe Isotopes in Charcoal.” Journal of Radioanalytical and Nuclear Chemistry, 181(2):291-299.
Vance JN, JE Cline, and DE Robertson. 1995. Characterization of Carbon-14 Generated by the Nuclear
Power Industry. EPRI-TR-105715, Electric Power Research Institute, Palo Alto, California.
Yim MS and F Caron. 2006. “Life cycle and management of carbon-14 from nuclear power generation.”
Progress in Nuclear Energy, 48:2-36.