ML20148F229
| ML20148F229 | |
| Person / Time | |
|---|---|
| Site: | Paducah Gaseous Diffusion Plant |
| Issue date: | 02/28/1997 |
| From: | Brown N, Chen J, Lombardi D LAWRENCE LIVERMORE NATIONAL LABORATORY |
| To: | |
| Shared Package | |
| ML20148F236 | List: |
| References | |
| UCRL-ID-126275, NUDOCS 9706040181 | |
| Download: ML20148F229 (73) | |
Text
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PADUCAH G ASEOUS DIFFUSION PLANT SEISMIC RISK STUDY URCIrID-126275 dated February 1997 i
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1 Paducah Gaseous Diffusion Plant Seismic Risk Study
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1 Neil W. Brown, Jian-Chu Chen, Douglas A. Lombardi *,
Stephen C. Lu, Ryan Roehnelt i,
Lawrence Livermore National Laboratory University of California /Livermore, California February 1997 h44
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This is an informal report intended primarily for internal or limited external T[fgg id_.
p 7-distribution.1he opinions and conclusions stated are those of the author and may or may not be those of the Laboratory.
A Work performed under the auspices of the U.S. Department of Transportation and Tggj@ tin, F- {
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$fpg' the Department of Energy by the Lawrence Livermore National Laboratory under 3MIM Contract W.7405-Eng-48.
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j Paducah Gaseous Diffusion Plant Seismic Ris'k Study
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l Manuscript date: February 1997 Neil W. Brown Jian-Chu Chen Douglas A. Lombardi (ORNL)
Stephen C. Lu Ryan Roehnelt Lawrence Livermore Nationil Laboratory University of California /Livermore, California
Disclaimer This document was prepared as an account of work sponsored by an agency of the United States Government. Neither the United States Government nor the University of California nor any of their employees, makes any warranty, express or implied, or assumes any legal liability or responsibility for the j
accuracy, completeness, or usefulness of any information, apparatus, product, or process disclosed, or represents that its use would not infringe privately owned rights. Reference herein to any specific commercial product, process, or service by trade name, trademark, manufacturer, or otherwise, does not necessarily constitute or imply its endorsement, recommendation, or favoring by the United States Government or the University of California.
The views and opinions of authors expressed herein do not necessarily state or reflect those of the United States Government or the University of California, and shall not be used for advertising or product endorsement purposes.
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Work performed under the auspices of the U.S. Department of Energy by the Lawrence Livermore National Laboratory under Contract W-7405-Eng-48.
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I Contents Acronyms........................................................................................................
iv A c kn o w l e d gm 2 n ts......................................................................................
v Execu ti v e S um m a ry.......................................................................................
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- 1. B a ck gro un d............................................................................................
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- 2. In tr o d u cti o n............................................................................. - -
- 3. Summary Descrip tion of Facilities.........................................................
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- 4. Description of Approach, Data, and Assumptions................
- 5. Summary Discussion of the Seismic Hazard at Paducah.....................
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- 6. Damage States of Structure., and Equipment....................................
. 13
- 7. Source Terms and Transport of Released Material..........................
N 7.1 Source Terms...................................
-.S 7.2 Transport o f Released Material.......................................................
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- 8. Population Distribution and Emergency Response.............................
36 8.1 Population Distribution.......
.36 8.2 Emergency Response.....................................
37
- 9. He al th Co nse qu ences................................................................................
39 9.1 Hyd ro gen Flu o rid e.................................................................................. 39 9.2 Uranium Oxyflu o ride...............................................
20 9 3 Clou d o f Mixed Ma terial....................................................................
... 41
- 10. C al cula tio n o f Ris ks.......................... -.......-.-...................................-...
.43
- 11. Comparison with Other Industrial Risks...................................................... 49
- 12. C o n cl u s i o ns.......................................-....... --. --........................-..... -
52 References....................................................................................................
,m Appendix A: Processing of Meteorology Data..............................................
.56 Appendix B: Calculated Values of X /Q..........................................................
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Tables Table 6-1. C-331/C-335 Building and Equipment Failure Modes Summa-ized fromRef.4.........................................................................................
14 Table 6-2. C333/C337 Building and Equipment Failure Modes Summarized fromRef.4.........................................................................................._16 Table 6-3. Summary Description of Basic Equipment and Building Damage Levels for Four Process Buildings...................................................
20 Table 6-4. Fragility Characteristics for Equipment, Bellows, Tie-Lines, and B u i ld in g Un its.......................................................................................
H Table 6-5. Fragility Characteristic for Basic Damage States.~........................... 24 Table 6-6. Fragility Characteristic for Basic Damage States (Buildings C-331 and C-335 Unmod ified)............................................................................... 25 Table 6-7. Probability of Damage Level for Upgraded and Non-Upgraded C-331/ C-335 B uildin gs.............................................................................
... 2 "
Table 7-1.' Basic Released Masses, Log Normal Distribution...................
.. 32 Table 7-2. Source Conditions used to Compute X/Qs..................................
... 32 Table 9-1. Health Hazards from Exposure to HF.......................................
... 39 Table 9-2. Significant HF Concentrations in Air............................................ 40 Table 9-3. Health Effects From Intake of Soluble Uranium........................
.. 41 Table 10-1. Consequence Thresholds Used in Calculating Risk..................
.. 43 Table 10-2. Statistics for Case with Seismic Upgrades and No Emergency Actions...............................................................................................................45 Table 10-3. Comparison of the Case with No Seismic Upgrade to the Case with Seis mic Up gra d e................................................................................... 46 Table 10-4. Comparison of Off. Site Injuries for the " Upgrade" and "No Up gra d e " C ases................................................................................................ 47 Table 10-5. Comparison of On-Site Injuries for the " Upgrade" and "No Up gra d e " Cases............................................................................................ 47 -
Table 10-6. Comparison of the Cases with Emergency Response (ER) wi-h Those Ha ving no ER................................................................................... 48 Table 11-1. Production of Selected Chemicals With Hazard Characteristics Simil a r to UF6, T / yr........................................................................................ 49 Table 11-2. U.S. HF Production Capacity............................................................ 50 Tab le 11-3.= Users o f HF............................................................................................. 50 Table 11-4. Probability of Spills Associated with Shipments to Four Oil Refiners in Los Angeles Area........................................................................... 51 Table B-1. Source 1 Dispersion Factors.....................
. 57 Table B-2. Source 2 Dispersion Factors.........................................................
.. 58 Table B-3. Source 3 Dispersion Factors..........................................................
.. 59 Table B-4. Source 4 Dispersion Factors.............................................................. 60 Table B-5. Source 5 Dispersion Factors.'............................................................. 61 Table B-6. Source 6 Dispersion Factors................................................................. 62 ii
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1 Figures Figure 3-1. Paducah Gaseous Diffusion Plant, Paducah,.........................
4 Figure 3-2. Schematic Plan View of Four Main Process Buildings (C-335, C-337, C-310, and C-333 A)........................................................
.. _5 Figure 5-1. Hazard Curves Computed from the Extended-Source Hazard Analysis for Rock Site Conditions at Paducah (Risk Engineering,1993) Error! Boo's=a Figure 8-1. Projected Daytime Population Distribution at the PGDP Site in Ye a r 2000.........................
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ACGIH American Conference of Governmental Industrial Hygienists AIHA American Industrial Hygiene Association COV Coefficient of Variation DOE Department of Energy DOE-OR Department of Energy, Oak Ridge EHS Extremely Hazardous Substance EPA Environmental Protection Agency EPRI Electric Power Research Institute EPRG Emergency Planning Response Guideliness EUS Eastern United States GDP Gaseous Diffusion Plant HCLPF High Confidence Low Probability of Failure IDLH Immediately Dangerous to Life or Health j
LLNL Lawrence Livermore National Laboratory LMES Lockheed Martin Energy Systems NIOSH National Institute for Occupational Safety and Health ORNL Oak Ridge National Laboratory OSHA Occupational Safety and Health Administration PEL Permissible Exposure Limits PGA Peak Ground Acceleration PGDP Paducah Gaseous Diffusion Plant
'PRA Probabilistic Risk Assessment SAR Safety Analysis Report i
SARU Safety Analysis Report Upgrade TLV Threshold Limit Value TWA Time-Weighted Average USGS United States Geological Survey WES Water Experimental Station iv
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Acxnowledgments The authors hereby acknowledge and thank James Carter (ATI) and Kenneth Keith (Lockheed Martin Energy Systems) for their guidance on the application of the Safety Analysis Report Upgrade program documentation used in this study, and for their helpful review of this report. Similarly, we want to thank both Gerry Mok and Garry Thomas of Lawrence Livermore National Laboratory for their council on various portions of this study and their review of this report.
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Executive Summary One of the concerns that has arisen from the Gaseous Diffusion Plant (GDP)
Safety Analysis Report Upgrade (SARU) program is the question about the vulnerability of the Paducah Gaseous Diffusion Plant (PGDP) to earthquakes.
The design and construction of the PGDP is essentially the same as the Portsmouth GDP, but the PGDP site is in a region of higher seismicity and therefore there is a higher likelihood of buildings and equipment being damaged by an earthquake. In addition to the " normal" hazards associated with earthquakes, damage to the process equipment can lead to release of the toxic uranium hexafluoride gas. This study evaluated the health risk to the public and workers caused by potential exposure to the toxic materials from earthquake-caused releases of uranium hexafluoride (UF ). The study was 6
completed to provide an improved understanding of the risk to workers and j
the public from earthquake damage to the plant. Other hazards associated with earthquakes were not considered. The study was also intended to support considerations that may arise concerning upgrading portions of the facility to better resist earthquakes.
The study covers the scope of a seismic risk assessment using the information and analytical results from the SARU program. The results of these analyses have been used by LLNL to support estimates of the probability and extent of damage from earthquakes. The level of damage has been correlated with release of uranium hexafluoride processed in the plant. The health consequences from the various levels of release have been interpolated and extrapolated from detailed analyses performed for the SARU program. The probability of earthquake damage producing severe health consequences has been determined using well documented hazard characteristics of uranium hexafluoride. The probabilistic information was entered into a Monte Carlo model for potential failures resulting in release and exposure to the population. A comparison has also been made of the seismic risk at the PGDP to the public associated with the transportation of h'ydrogen fluoride, sulfuric acid and chlorine-chemicals with a hazard similar to the uranium hexafluoride used in the PGDP.
The results of the study show that the health risk from earthquake-caused releases of uranium hexafluoride at the PDGP is small, and probably less than risks associated with the transportation of hydrogen fluoride and other similar chemicals used by industry. The probability of more than 30 individuals experiencing health consequences (injuries) from earthquake damage is less than 4x104/yr, even if the planned modifications to buildings C-331 and C-335 were not completed. With the planned modifications completed, the probability of more than 30 injuries is reduced to 2x104/yr. No fatalities are predicted to occur, even in the most severe earthquakes. Thus, it vi
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is concluded that the reduction in seismic risk that will be realized by structurally upgrading buildings C-331 and C-335 is small. These results are primarily due to'the fact that the inventory of uranium hexafluoride in C-331 q
and C-335 is small compared to the totalinventory on site, and the population density in the vicinity of the plant is low. Therefore, even though the probability of earthquake damage to buildings C-331 and C-335 is relatively high in their current condition, the health risk is low.
i The risk model includes a very approximate model of the on-site population exposure to UF, and therefore the model is not an accurate predictor of the 6
total risk to the worker. For example, the risk model only includes the risk i
due to UF release, but the workers in buildings are also exposed to the risks 6
from falling structures, which have not been considered. Also, the analytic -
results do not consider the impact that earthquake damages could have on production, or the perceptions that the community may have from j
earthquake-caused releases. These factors do not lend themselves to the simplified analyses completed in the study, but may have importance to the decisions intended to reduce risk.
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===1.
Background===
The Paducah Gaseous Diffusion Plant (PGDP) has been operating, essentially continuously, for over 40 years. Its operations are well understood, and the safety record concerning the workers and the public surrounding the plant has been exemplary. Facility modifications, numerous safety studies, and improvements over the years have contributed to plant safety. Most recently, an extensive effort has been made, under the Gaseous Diffusion Plant (GDP)
Safety Analysis Report Upgrade (SARU) program, to upgrade the safety analysis and operational safety basis, and this effort is nearing completion.
Lawrence Livermore National Laboratory (LLNL) has assessed the adequacy of selected SARU program documents for the Office of Facilities, DOE Germantown (Ref.1). The seismic risk study reported herein has been completed by LLNL in conjunction with the previous assessment activity.
This study has been undertaken to provide an improved understanding of the PGDP risk to workers and the public from postulated earthquake damage to the plant. It is also intended to support ceasiderations that may arise concerning upgrading portions of the facility to better resist earthquakes.
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2.
Introduction One of the environmental and safety risks associated with gaseous diffusion plants is the accidental release of a large amount of UF, a gaseous material 6
used in this uranium enrichment process. The PGDP equipment and piping routinely contain one million pounds of this gas during plant operations.
When UF is released to the atmosphere,it forms toxic compounds that are 6
easily transported into the atmosphere. One of the mechanisms able to cause this release is an earthquake of sufficient strength to cause cracks or other severe damage to the piping and equipment that contain the UF. Such an 2
6 event is both very unlikely and very uncertain, but if it were to occur it could produce serious health or environmental consequences. This study assessed the probability of earthquakes causing UF leakage, and the health 6
consequences of subsequent transport of the material to areas where people may be located. These estimates were then combined in a analytical model to characterize the risk.
The SARU program has produced recent studies of the seismicity of the site, and updated evaluations of the structures and equipment response to earthquakes (Refs. 2 through 10). These studies have identified vulnerabilities of the PGDP buildings and equipment to earthquake damage. The results of these studies have been used by LLNL to support estimates of the probability and extent of damage from earthquakes. The consequences from various levels of release have also been interpolated and extrapolated from detailed analyses performed for the SARU program. Thia rtudy covers the scope of a seismic risk assessment, but in less detail, and they rely heavily on SARU program results and engineering judgment.
Section 3 of this report provides a brief descrir r of the PGDP and the surrounding community. Section 4 describes ti e ap}ecach used to evaluate and extrapolate the SARU analyses and the ass.mptions necessary to complete this study. Section 5 summarizes the seismic he,ard (probability of earthquakes as a function of severity) at the PGDP site. Section 6 describes the damage conditions used to estimate release of UF and their probability of 6
occurrence as a function of earthquake intensity. Section 7 discusses the release and transport of UF both within the buildings and off-site. Section 8 6
discusses the population, both on-and off-site, and the effect of time of day and emergency response on the probable exposure of people. Section 9 summarizes the toxicity characteristics of the released materials and air concentration thresholds used in the analysis of risk. Section 10 presents the risk results and describes how the calculations were performed. Section 11 discusses the hazards associated with industrial use of hydrogen fluoride (HF), sulfuric acid (H2SO.o; and chlorine for comparison to the seismic risk at the PGDP. Section 12 presents conclusions.
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3.
Summary Description of Facilities The PGDP is one of two gaseous diffusion plants in the U.S. producing enriched uranium for the manufacture of nuclear reactor fuel. Figure 3-1 shows an aerial view of the PGDP site. The four large buildings in the center of this figure contain the gaseous diffusion process equipment, and are the focus of this study. The process system consists of thousands of circulators l
(compressors), converters (which are vessels containing diffusion barriers),
l valves, and the piping that connects the thousands of pieces of equipment.
The process equipment and piping contain UF, which is maintained at an 6
elevated temperature (250 *F) and at a few psig of vacuum over most of the system volume. Figure 3-2 shows a schematic plan view of the four process buildings and the inventory of UF distributed throughout the process system 6
when the plant is operating at 2,200 MW.
i The buildings consist of a number of independent frame structures (8 in each of the two small complexes and 30 in each of the two large complexes) with separation gaps that are about 4 inches wide at the roof level and 3 inches wide at grade level. The large buildings are approximately 1,000 feet on a side and 85 feet high, while the smaller ones are about half that size. The process system piping and equipment containing the UF is located on the second 6
floor of these buildings. The process systems in the four buildings are connected by tie-line piping that is housed in the overhead structures, which '
support the tie-line piping at the second floor level provide insulating enclosures. The ground floor contains electrical controls and auxiliary equipment, while the area above the process equipment houses cranes to service the equipment.
The gaps between the independent frame structtres are covered at the roof level and second-floor level with flexible arrangements that allow relative movement between structures. There are numerous bellows in the piping system, some of which are located at these gaps to allow for system expansion
- and relative movement of buildings during earthquakes.
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{I 1.297) 19 C C-333-A 523,556 Figure 3-2. Schematic Plan View of Four Main Process Buildings (C-335, C-337, C.310, and C-333A) 5
The PGDP facilities that could release enough hazardous material to cause major concern ar'e those containing gaseous and liquid UF. In addition to the 6
four process buildings, gaseous and liquid UF is contained in cylinders inside 6
buildings C-315, C-310a, C-333A, C-337A, and C-360, where feed, product, or tails material is introduced or withdrawn from the system. Some liquid-Elled cylinders are also located outside these buildings, where they are set in cradles to cool until the liquid freezes, prior to further movement for shipping or storage. On a temporary basis, liquid UF may also reside in the accumulators 6
used to control the inventory in the process systems. This study did not consider the contributions to the source terms from possible damage to tese cylinders or other facilities. This omission is judged to be insignificant to the risk estimates because of the low probability of an earthquake occurring simultaneously with high inventories in containers that are vulnerable e damage. The liquid filled cylinders have been shown not to be vulnerable to earthquake damage.
l Many other buildings and auxiliary systems that are associated with the plant were not addressed in this study. The PGDP uses hazardous materials in addition to UF6, but the off-site risks from earthquake-caused releases of Se other hazardous materials are projected to be significantly less than those from the UF, and therefore were omitted from this study. Refs. 8 and 9 6
provide some justification for this omission. The significance of the other hazardous materials to on-site risks is discussed in Section 8.
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4.
Description of Approach, Data,and Assumptions t
A simplified model of the PGDP and its potential earthquake-caused failure states has been develeped to implement calculation of the seismic risks from release of UF. The model was developed using the commercial computer 6
code Crystal Ball (Ref.11), which uses Monte Carlo simulation methods to evaluate analytical models constructed on a spreadsheet. The following factors have been included in the development of this probabilistic model:
- 1. The inventory of UF in the plant (amount and distribution shown in 6
Figure 3-1).
- 2. The annual probability of earthquakes (see Section 5).
- 3. The probability of earthquakes causing leaks in equipment containing UF,6 or causing structural damage to the buildings that support the equipment and mitigate the off-site release of UF (see Section 6).
6
- 4. The uncertainty in the magnitude of UF release (see Section 7).
6 l
- 5. The natural randomness of the atmospheric transport processes.
- 6. The population.
Data were readily available for factors 1,2,5, and 6 of the model. Figure 3-1 shows a very likely distribution of the material inventory in the four process buildings when the plant is operating at 2,200 MW. This inventory distribution was used in the study, and it was assumed to be fixed at the levels and distribution shown. In fact, the inventory does vary, sometimes daily and frequently weekly, so the inventory at the time of an earthquake might be less than that shown in Figure 3-1. The assumption introduces a small conservatism into the analysis because the assumed inventory is the maximum at which the plant is likely to operate in the foreseeable future.
Some of the locations in the facility with reduced or zero inventory may have increased inventories in the future, but inventories would be decreased elsewhere in the buildings. The impact of such operational adjustments at the power level of 2,200 MW would be insignificant to the risk estimates made in this report. Higher power levels, up to the design level of 3,050 MW, with associated increases in inventory, would require a major investment in new heat-rejection equipment.
Section 5 discusses the data used to estimate factor 2, the annual probability of earthquakes and the uncertainty in these estimates. The uncertainty in the seismic hazard curve, although large and typically an important parameter in seismic risk assessments, has not been included in the calculation. It was judged that the uncertainty in damage states, releases, and meteorology would dominant the overall calculational uncertainty. Inclusion of the 7
uncertainty in the seismic hazard curve would add computational complexity that was judged to be unnecessary to obtaining reasorable risk estimates.
Two years (1991 and 1992) of hourly site meteorological data were used to develop a joint probability distribution of wind speed, stability, and direc-ion for use in the risk model. The processing of these data to develop the input to the Crystal Ball code is discussed in Appendix A.
i The extent of damage to the facilities and the associated release of materil (factors 3 and 4) are the most difficult factors to estimate. The variability in possible damage and the associated UF release paths are extremely large and 6
very uncertain. The approach taken to address this problem was to identif a f
small number (five, counting the no-damage state, fcr the small buildings, and six for the large buildings) of damage states for the four process buildings.
The method for calculating the annual probability of one of these levels of damage being caused by an earthquake is discussed in Section 6.
Probabilistic distributions of the release associated with each damage state were estimated based on evaluations that have been completed for the SAR (Refs. 2,9,10) and the definitions of the damage states used in the model.
These distributions are discussed in Section 7. The damage states and the distributions for the releases were selected to cover the spectrum of possible outcomes.
The population distribution used in the risk calculation and the variations are discussed in Section 9. They are always assumed to be known and fixed, although the distribution, as function of time, is variable. Variations due to emergency response actions, or the difference in nighttime and daytime distributions, are included in the analyses.
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S.
Summary Discussion of the Seismic Hazard at Paducah i
Extensive analyses of seismic hazard at the PGDP site were performed by Risk Engineering, Inc. as part of SARU program (Ref.12). The development followed the guidelines provided by DOE-STD-1024-92 (Ref.13). This standard was intended to provide guidance in the use of the seismic hazard curves developed by the Lawrence Livermore National Laboratory (Ref.14) and the Electric Power Research Institute (Ref.15). Experience has shovm that application of these methodologies can yield sigmficantly different results. In response to this issue, a Seismic Working Group was formed by the Department of Energy (DOE). The position developed in the DOE standard was intended for immediate use in developing seismic hazard estimates at DOE sites for evaluating new and existing, nuclear and non-nuclear DC' facilities. Risk Engineering, following the guidance of this DOE standarc performed three separate probabilistic seismic hazard analyses for the si:e.
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Their analyses included:
- 1. Using the EPRI methodology for seismic hazard assessment in the Central and Eastern United States.
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- 2. Using the LLNL methodology that was performed at LLNL. Results were transferred to Risk Engineering.
- 3. A fault source model (the extended line source) for the New Madrid seismic zone, constructed and analyzed by Risk Engineering.
l 1
Because both the EPRI and LLNL methodologies treat earthquakes as point sources, their results are not directly applicable to the PGDP site, because of the possibility of large earthquakes at the fault sources in the New Madrid seismic zone, which should be modeled as extended-line sources. DOE-STD-1024 requires that the extended line source seismic hazard analysis be performed at the site.
Risk Engineering's investigations were subsequently reviewed by the United States Geological Survey (USGS 1992, Ref.16) and compared to independent studies performed by USGS. The USGS found that the median values of the Risk Engineering and LLNL's investigations were very similar to the USGS central values of ground motions obtained at 1,000-year return periods at the plant site. USGS accepted the probabilistic hazard estimates as appropriate values for use in the evaluations of structures, systems, and components for seismic structure integrity and seismic design of new and improved j
. structures, systems, and components at this site.
The mean hazard curve shown in Figure 5-1 is for horizontal components.
The vertical components are two-thirds of horizontal components. The technical basis for these recommendations is derived from site-specific 9
1 l
PADUCAH (RdCK)
EXTENDED-SOURCE RESULTS - PEAK ACCELERATION 10-1
-.-.... 0.85 fractue c
1 0.50 fractue :
)
O
.\\
0.15 fractHe c
.g 1g_,,g,
.a.
s,,
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i o
s x
g i
Ec s
1 s
010-3 N
4 s
s
.c s
o s
s.,
s a
s N
s 810-4
's
~. '
a s
.., 5 c
c s
a
~
~
's%
i
%'3 5
100.00 m
0.25 0.50 0.75 1.00 Peak Acceleration (g)
Figure 5-1. Hazard Curves Computed from the Extended-Source Hazard Analysis for Rock Site Conditions at Paducah (Risk Engineering,1993) e 10
geotechnical and' geophysical studies, seismic hazard assessments at rock outcrop, as developed by Risk Engineering, and site response evaluation performed by the Army Corps of Engineers Water Experimental Station (WES) (Ref.17). As components of the seismic analysis and characterization program were accomplished, the results were presented to the DOE community and its industrial consultants. Technical issues and questions were resolved. The mean values of the seismic hazard curve at PGDP were finalized for use in seismic analysis of PGDP structures, but the standard deviation values related to the mean hazard curve were not specifically determined.
Probabilistic seismic hazard analysis incorporates the random variability in the location, size, and ground motions associated with future earthcuakes. In addition to this random variability, there is also a cornponent of uncertainty i
related to the lack of knowledge of the models and parameters that characterize the seismic hazard. These uncertainties result in a distribution of seismic hazard curves from which the median, or any percentile and mean, seismic hazard curves may be generated.
Uncertainties are associated with each element of seismic hazard evaluation.
Uncertainty about seismic sources arises because multiple hypotheses exist regarding the causes of earthquakes in the Eastern U.S., and knowledge of the physical characteristics of tectonic features is incomplete. Uncertainty may j
also arise about the geometry of a seismic source. Uncertainty in seismicity comes from the selection of maximum magnitude and seismicity parameters.
Uncertainty in the attenuation functions arises from alternative hypotheses about dynamic characteristics of earthquakes in the Eastern U.S. All of these contributors to uncertainty were considered and quantified in the seismic hazard analyses completed for the PGDP site.
The results of seismic hazard analysis completed for extended-source and rock site conditions at the PGDP site are shown in Figure 5-1. The uncertainty of the hazard estimates are shown by 15 percentile (or fractile), median (i.e.,0.50 percentile),85 percentile, and the mean curves. It can be seen from this plot that the mean and the median curves are almost identical up to about 0.3 g.
j Deviation begins at 0.3 g. The median at 0.5 g is not significantly different from the mean. These results suggest that the mean hazard and the median hazard are about the same within this range, particularly up to 0.3 g. The mean hazard curve can be approximately expressed as y = 3.5 x 10-5 Z-2.5, where z is the PGA and y is the annual probability of exceedance. The variation from the effect of soil conditions is insignificant based on the results of site response analysis shown in Ref.17.
l 11
It was initially intended that the uncertainty in the hazard curves would be included in the isk model; however, this has not been done because i
uncertainties in th equipment damage level, and associated material i
releases, appeared to be dominant uncertainties. The additional computational complexity associated with sampling the uncertainty in the seismic hazard curve was not warranted, and, therefore, only the mean value curve in Figure 5-1 has been used.
i L
1 12 J
l
1 6.
Damage S' tates of Structures and Equipment Failure mechanisms, failure modes, damage levels, and damage states a e discussed in this section. A failure mechanism is the physical process that causes failure to occur. Material yielding or fracture are typical failure mechanisms. A failure mode is a type of failure in a structure or component, such a cracked bellows. The level of damage is a general term used to characterize a broad state of damage in a building, while a damage state is the damage considered to exist in all four process facilities included in this risk study.
As described in Section 3, the PGDP process buildings (C-331, C-333, C-335, and C-337) consist of many nearly identical individual structural units separa:ed by gaps. C-331 (or its identical building C-335) has eight units and C-333 (or its identical building C-337) has 30 units.
A set of damage states associated with building structures and equipmen: has been developed, based on information in Refs. 2 through 6, that summa-ize detailed analyses and walkdown results in Design Analysis and Calculat on Reports (DACs). The DACs were reviewed, but were not used in development of the probability of the damage status used in this study. The damage states described below, and used in the risk calculations, have been based largely on the modeling assumptions described in this section and in Section 7.
Failure modes, along with their High Confidence Low Probability of Failure (HCLPF) values identified in Rcf>. ? through 5, are summarized for the equipment and each structural unit in buildings C-331/C-335 and C-333/C-337, _
respectively, in Table 6-1 and Table 6-2 Descriptions of the failure modes of equipment with HCLPF capacity greater than 0.15 g were not included in the referenced documents because the building's capacity had been reached. This information was developed by the SARU program and was based on analysis and judgment for which our review provided no reason to take exception, and therefore it was used as the basis for developing the probabilities of the damage states used in the risk calculations.
The failure mode descriptions in building complexes C-331 and C-335 include a " rocker-arm" failure of the support beams used to accommodate expansior between the building units. This feature has been a subject of much discussion within the GDP program, and DOE-OR is implementing a program to strengthen the buildings that will reduce the probability of this mode of failure occurring. The building modifications that will be performed for these buildings is expected to raise the building HCLPF capacity from 0.05 g to 0.15 g.
13
Table 6-1. C-331/C-335 Building and Equipment Failure Modes Summarized from Ref. 4 HCLPF Capacity (g)
Failure Mode
<0.05 Failure of axial support (Type 184) of the unit bypass (A Stream) near Unit 4.
May lead to the tear of one 30-in. expansion joint at the end of the pipe segment. (One such support in the building).
Failure of axial support (Type 184) of the unit bypass (B Stream) near Unit 4.
May lead to the tear of one 30-in. expansion joint at the end of the pipe segment. (One such support in the building).
Tear of two 24-in. expansion joints (Type x-9) at each end of loop in A-Stream.
cell bypass near Cell 9. (Two in each unit).
0.05 Failure of lateral piping support (Type 30), cell bypass, A Stream. Piping becomes unrestrained laterally. Further consequence to be determined. (One in each unit).
Failure of the " rocker arm" support beam at the roof level of the " unmodified" building. (Three in the building). Building will not collapse. Bleach of the pressure boundary as a consequence of the failure of rocker arm beams is o be determined.
0.06 Cut hinge, Unit 4, Cell 3, Stage 5 (B Stream). May lead to the tear of 24-in.
expansion joint.
Failure of lateral supports (Type 121 and 139) of the unit bypass near tie line to C-333 (A Stream). May lead to the tear of two 30-in. expansion joint in vicinity. (One place in the building).
Failure of vertical support (Type 106), unit bypass at cell bypass, A Stream.
May tear 30-in. expansion joint. (One in the building).
0.08 Failure of the " rocker arm" support beam at the mezzanine level of the
" unmodified" building. (Three in the building). Building will not collapse.
Bkach of the pressure boundary as a consequence of the failure of rocker ann beams is to be determined.
0.09 Failure of compressor anchorage of unanchored Stage 1 converter in Cell 9.
Converter 30-in. "A/B" stream inlet expansion joint may tear and compressor drive shaft and rotor may be affected.
0.10 Failure of lateral supports (Type 121 and 139) of the unit bypass near tie line to C-333 (B Stream). May lead to the tear of one 30-in. expansion joint in s icinity. (One place in the building).
Failure of the " rocker arm" support beam at the cell level of the " unmodified" building. (Three in the building). Building will not collapse. Bleach of the pressure boundary as a consequence of the failure of rocker arm beams is to be determined.
/
14
~
____..~_._._____._.__._m._._..
I 1
Table 6-1. C-331/C-335 Buildin5 and Equipment Failure Modes Summarized fron Ref. 4 (continued)
- Capacity (g)
Failure Mode 0.10 (cont.)
Failure of anchorage at building column base, leading to column base uplift during earthquakes. The nonlinear analysis has proved that the building will not overturn, and the building can continue to resist seismic load to hi her earthquake levels.
l 0.11 Failure of pipe flange in cell bypass, A Stream. May lead to 24-in. A st eam leaks at flange. (One in each unit).
0.12 Failure of compressor anchorage of unanchored Stage 1 converter in cells.
Converter 30-in. A/B" stream inlet expansion joint may tear and compressor drive shaft and rotor may t>e affected.
Building tie-line structures start to fail.
Structural failure starts to occur at various connections of column line X a.d Chevron bracing, floor beams, and truss chords of the " unmodified" building, based on estimate because of unavailable analytical results.
0.13 Failure of axial support (Type 120) at valve in the unit bypass at cell bypass (B Stream). May lead to the tear of 30-in. expansion joint. (One each in units 1.
2, and 3).
Failure of axial support (Type 120) at valve in the unit bypass at cell bypass (A Stream). May lead to the tear of 30-in. expansion joint. (One in each unit).
l 0.15 Expansion joints (bellows) start to fail.
Structural failure starts to occur at various connections of column line X and -
j Chevron bracing, floor beams, and truss chords of the " modified" building.
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15
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l Table 6-2. C333/C337 Building and Equipment Failure Modes i
Summarized from Ref. 4 l
HCLPF Capacity (g)
Failure Mode
<0.05 Unanchored "B" Booster Station coolers. Inertial effects may tear all bellows in the booster station. ('Ihree coolers affecting three bellows each).
Failure of pipe support types 2,3,4,4a, and 5 on the "B" stream piping. May tear all the bellows in the "B" Booster Station. (Same bellows as above).
j Unrestrained piping in the unit bypass. May tear the X-11/11A pressure balanced expansion joint on the "B" stream. (One location in the building).
Unrestrained piping in the unit bypass. May tear the X-10/10A pressure balanced expansion joint on the "B" stream. (One location in the building).
0.06 Differential motion of the building and the process tie line. May tear bellows types H3-OX-7,8 and 11. (This condition occurs at one location in the building and involves two "A" stream and on "B" stream expansion joints).
Failure of anchor type 86. May tear the adjacent "A" stream bellows. (Tnis condition occurs only at one location in the building).
0.10 Failure of anchorage at building column base, leading to column base uplift during earthquakes. The nonlinear analysis has proved that the building will not overturn and the building can continue to resist seismic load to higher earthquake levels.
2.0.10 All other components have HCLPF capacities equal to or greater than 0.1g.
0.12 Building tie-line structures start to fail.
Structural failure starts to occur at various connections of column line X and K bracing, beams, and truss chords of the " unmodified" building.
0.15 Expansion joints (bellows) start to fail.
Structural failure starts to occur at various connections of column line X and K bracing, beams, and truss chords of the " modified" building.
This seismic structural upgrade is assumed to have been completed in the base case risk evaluation. A parametric case study was completed that uses building failure probability values consistent with no upgrade of the building structures. This assumption not only introduces the potential for the " rocker-arm" failure mode, wiuch is not specifically addressed in the analysis, but the more severe conse.quence of building unit collapse that is estimated to occur at nearly the same level of earthquake as the " rocker-arm" failure mode. The l
probability of a building unit collapse in a low-level earthquake is increased in the parametric case to correspond to the performance expected from the building structure without the proposed upgrade.
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APR-09-97 WED 1029
.BOOZ* ALLEN & HAlilLTON FAX NO. 3019107373 P.02 i
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The failure modes contained in Tables 6-1 and 6-2 are listed in accordance
)
with the increasing order of their HCLPF capacities. The HCLPF value is the
)
,[
high confidence (95%) low probability (5%) failure estimate of the seismic capacity associated with an equipment or structure component. Therefore, it j
is extremely unlikely that any component will fail at its HCLPF capacity. The referenced reports provide estimates of the HCLPF for various structures or components, not necessarily the damage states developed for use in the l
seismic risk model in this study. Both the values provided in the referenced l
l~
report, and 'the application of that information in this report, required engineering judgment based on specific analysis and results of walkdown inspections.
From the failure modes listed in Tables 6-1 and 6-2, numerous damage levels in each of the four building complexes, and damage states resulting from combinations of failures in buildings and equipment, could be created. For each damage state a probability and consequence can be identified. For example, nine damage levels (i.e., the damage of 0,1,2,.... up to all eight structural units in the building complex) could be selected for C-331 or C-335.
Likewise,31 damage levels could be identified for C-333 or C-337.
~
Combinations of all these damage levels in the four building complexes result in a total of 77,841 combinations of building damage states (not including the cases of damage to equipment and expansion joints inside the building). Of course, many of these combinations are unrealistic, but a very large number.of realistic cases could be realized in an earthquake. In order to N- '
simplify the risk model~for the PGDP process buildings,13 basic damage levels
-have been selected. From these basic damage levels, combinations of damage states in the four process building complexes were developed and the probabilities computed.
The 13 basic damage levels used in the risk analysis cover the range of
~
damage, from no damage up to a level of damage that opens the entire piping system in a particular building to the atmosphere. The 13 damage levels are described as follows, and are summarized in Table 6-3 as applied to the four process buildings.
For building C-331 and C-335, five damage levels are Identified:
Level 0 damage, identified as F0A for C-331 and FOB for C-335, indicates no damage to building structures and equipment. (A = C-331, B = C-335, C =
' C-333, and D = C-337 in the following discussions and Table 6-3.)
Level 1 damage, identified as FIA and FlB, is associated with the failure of weak equipment links in each building complex, with no damage to expansion joints and structures that would reduce their mitigation effects.
Results of the evaluation of equipment and piping systems reported in Ref. 8 identified an extended list of weak links of equipment at PGDP. Some of these 4
weak links have very low seismic capacities, i.e., HCLPF below 0.06g. In this y
i 17 4
m i
I risk study, a generic MCLPF of 0.05 g was used to examine the risk resulti.g from the failure, < some equipment with low seismic capacity. The judg.e=
concerning the extent of the damage in terms of leakage is discussed in Section 7.
Level 2 damage, identified as F2A and F2B, is associated with the failure :i j
process piping expansion joints (i.e., bellows) in each building complex, with no damage to building structures that would reduce their mitigation effe=s.
Expansion joints (and bellows) are used in the process buildings to connect pipe between adjacent structural units in order to allow differential movement of the units. Expansion joints have been identified as another weak link of the buildings during plant walkthrough processes. The fini report for the inspection and evaluation of expansion joints (Ref. 23) concluded that, with few exceptions, all expansion joint types have HCL F capacities that meet the acceptance criteria and the evaluation basis earthquake of 0.15g. In this risk study, a generic HCLPF of 0.12 g was used :o assess the risk associated with the failure of expansion joints.
Level 3 damage, identified as F3A and F3B,is the result of failure of a si-pe structural unit in the building complex. This is intended to cover the threshold of building structural failures that introduce serious damage te the process system boundary and the confinement barrier provided by the building envelope. It is assumed that the consequence of this damage level is the release of some of the material inventory in the building complex diactly to the environment. (See Section 7).
Level 4 damage, identified as F4A and F4B, is the result of failure of two er more individual structural units in the building complex. The assumed consequence of this damage level is that many openings have been created in the process system, and much of the building complex has been damaged. so the only mitigation is that afforded by debris and retention of UF and 6
reactants in the intact converters or other components.
For building C-333 and C-337, six damage levels are identified:
The damage levels assigned to this large building complex parallel those of the smaller buildings, except an additional failure level was identified to account for the increased size of the building complex.
Level 0 damage, identified as FOC and F0D, indicates no damage to building structures and equipment.
Level 1 damage, identified as FIC and FID, is due to failure of weak equipment links in each building complex, with no damage to expansion joints and building structures.
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APR-09-97 WED 14:30 B002* ALLEN & HAMILTON FAX HO. 3019167373
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- s.
, Level 2 damage, identified as F2C and F2D, is due to failure of expansion joints (bellows) in each building complex, with no damage to building
{
y v
structures.
S.
I Level 3 damage, identified as F3C and F3D, is the result of failure of one to four individual structural units in the building complex. As is the case with the smaller buildings, this is the threshold of serious damage to the buildings, and opening of a portion of the process system te permit direct release. It is
~
' assumed that the consequence of this damage level is the release of some of the mhterial inventory in the building complex. (See' Section 7).
i Level 4 damage, identified as F4C and F4D, is the result of failure of five to nine individual structural units in the building complex. This damage level
{
is introduced t exist for very s,o recognize the size of the complex and the fact possibilities eribus damage that is still short of total destruction. A great deal of material may still be retained in components for a lengthy period. The assumed consequence of this damage level is the release of an even larger fraction of the material inventory in the building complex. (See Section 7).
l Level 5 damage, identified as F5C and F5D, is the result of failure of ten or more individual structural units in the building complex. The assumed consequence of this damage level is similar to Level 4 damage in the smaller buildings. Additionally, it is assumed that many openings have been created in the process system, and much of the building complex has been damaged, i
so the only mitigation is that afforded by debris and retention of UF6 and reactants in the intact converters or other components.
For the tie-line structures, two levels of damage are identified:
j Level 0 damage, identified as FOT, indicates no damage to the tie-line structures.
Level 1 damage, identified as FIT, is identified as the failure of cross-over
]
piping (tie-lines) between building complexes. For simplification, it is assumed that all tie-line structures will fail or not fail at the same time.
1 Based bn the 13 damage levels,24 basic damage states, summarized in Tabfe 6-3, can be used to develop many combinations of building and equipment damage. There are 1,800 possible combinations, many of which are not realistic. One example is the case of no damage in any equipment or structures other than one building, which is at damage level 4. This is unrealistic'becau'sE if one. building.is at a high level of. damage, then it is very likely that other buildings and equipment have some damage. Hundreds of thousands of damage states are possible, and the selection of the discrete set analyzed in this study was made on the basis of the information available and -
simplification of the computations. The selection basis is discussed further in v
Section 7.
i 19 4
' Table 6-3. Summary Description of Basic Equipment and Building Damage Levels for Four Process Buildings I
FOA No failure in building complex A (C-331)
FOB No failure in building complex B (C-335)
' FOC No failure in building complex C (C-333)
F0D :
No failure in building complex D (C-337)
FOT No failure of tie-line structures FIA 1 Failure of weak equipment A in building complex A and no failure of bellows and building structures F1B Failure of weak equipment links in building complex B and no failure of bellows and building structures F1C Failure of weak equipment links in building complex C and no failure of bellows and building structures FID Failure of weak equipment links in building complex D and no failure of bellows and building structures i
FIT Failure of cross-over piping in building complexes F2A Failure of bellows in building complex A and no failure of building s:ructures F2B Failure of bellows in building complex B and no failure of building structures
- F2C Failure of bellows in building complex C and no failure of building structures
,F2D Failure of bellows in building complex D and no failure of building structures F3A Failure of 1 building unit in building complex A F3B' Failure of I building unit in building complex B j
F3C Failure of 1 to 4 building units in building complex C F3D Failure of I to 4 building units in building complex D j
F4A Failure of 2 to 8 building units in building complex A F4B Failure of 2 to 8 building units in building complex B F4C Failure of 5 to 9 building units in building complex C F4D F.ulure of 5 to 9 building units in building complex D j
F5C Failure of 10 to 30 building units in building complex C F5D-Failure of 10 to 30 building units in building complex D i
I 1
i
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r 20-
1 Calculation of Failure Probability and Damage States The standard procedure used to assess th.. seismic risk associated with a plant
' damage state requires the definition of fragility characteristics of specific failure mechanisms. The fragility is reprcented by the occurrence rate of the failure mechanism as a function of the earthquake level. The failure mechanisms of interest in the PGDP are those that result in release of UF3 from the process system.
The HCLPF values computed in the references and summarized in Tables 6-1 and 6-2 are conservative indicators of the seismic capacity of a structure er component, but the median capacity is more useful for defming component failure rates. The median capacity of a component is an earthquake level at which the component has a 50% chance of failure, and can usually be derived from the HCLPF. The median capacity C is commonly assumed to have a lognormal distribution with a lognormal' standard deviation.
Given the median capacity C and the lognormal standard deviation B, the fragility of a structure or component is commonly expressed by the following equation:
pp (a) = 4 [In(a/C)/B],
'(6.1)
~
~
where pp (a) is the conditional probability of failure of the component at a -
given earthquake with ground acceleration "a," and e the normal probabi'ity function. The fragility' expressed by Equation 6.1 as a cumulative distribution function of a standardized normal random variable "a" is an S-shaped cmve.
Table 6-4 lists HCLPF, median capacity, and values for the weak equipment -
links, expansion joints, and single structural units. The HCLPF values listed -
i in Table 6-4 are the result of engineering judgment and simplification
{
consistent with the information contained in Tables 6-1 and 6-2.
Table 6-4. Fragility Characteristics for Equipment, Bellows, Tie-Lines, and Building Units Component /
HCLPF Median Standard Structure Capacity (g)
Capacity (g)
Deviation Weak link equipment 0.05 0.11 0.46 Tie-line structures
. 0.12 0.25 0.46 j
Expansionjoints 0.12 0.25 0.46 Building unit (without mod.)
0.05 0.11 0.25 Building unit (with mod.)
0.15 0.32 0.25 21
The relationships between Table 6-4 and Tables 6-1 and 6-2 are quite clea-for tie-line structures and single building units. Equipment damage involves various extents of equipment failure and, according to Tables 6-1 and 6-1 the HCLPF varies from 50.05 g to 20.15 g. Since interest was limited to the failure of some weaker equipment for level 1 building damage, the HCLPF for Level I damage states was conservatively set at 0.05g. For expansion joint failu e, j
the HCLPF was set at 0.12 g, although 0.15 g was given in the expansion !oint report (Ref. 6). The slight reduction in attributed strength was based on review of earlier work than reported in Ref. 6; this earlier work indicated greater vulnerability.
The HCLPF values used for single building units and tie-line structures are 0.15 (0.05 g for unmodified units) and 0.12 g, respectively. The median capacity was calculated in accordance with the following equation from Ref. 21:
C = exp [ 1.65 ( Ba + Bu )] HCLPF (6.2) where Ba nd Bu are the lognormal standard deviations representmg a
randomness and uncertainty, respectively. As reported in Ref. 22, results of nuclear power plant Probabilistic Risk Assessment (FRA) studies indica:ed that plant-to-plant averages of 0.22 and 0.24 may be used for Ba nd Bc.,
i a
respectively. Based on these values, C = 2.14 HCLPF. The uncertainty parameter 8 is simply the sum of Ba and Bu. For equipment, expansion joints, i
and tie-line structures, a plant generic value of 0.46 was used. For building units,less uncertainty was assumed; a value of 0.25 was therefore used.
The cumulative distribution function, as shown by Equation 6.1, used to characterize the fragility, is denoted by pFEi pFB, PFT, or prs, respectively, to mdicate the probability of failure of equipment, bellows, tie-line structures, or a single building unit for a given earthquake magnitude. Using these notations, the fragility (or the conditional probability of failure for given earthquake, p(F0A) for the basic damage level F0A, or p(FIA) for the basic damage level FIA, etc. ) for any of the 24 basic damage levels can be calculated as follows:
i p(FOA) = 1 - p(F1A) - p(F2A) - p(F3A) - p(F4A)
(63.1) p(F0B) = 1 - p(FIB) - p(F2B) - p(F3B) - p(F4B)
(63.2) p(FOC) = 1 - p(FIC) - p(F2C) - p(F3C) - p(F4C) - p(F5C)
(633) p(F0D) = 1 - p(FID) - p(F2D) - p(F3D) - p(F4D) - p(F5D)
(63.4) p(F0T) = 1 - p(FIT)
, (63.5) p(F1A) = pra (1 - prs) (1 - prs)8 (63.6) 22
i i
. P(FIB) = p(FIA)
(63.7) i r
a
[
P(FIC) = pra (1 -pr,) (1 -pes)"
(63.8)
[
(63.9) i p(F1T) = prr (6 3.10) p(F2A) = prs (1 -prs)'
(6 3.11) l P(F2B) = p(F2A)
(63.12)
- p(F2C) = pra (1 - prs)3 (63.13)
{'
p(F2D) = p(F2C)
(63.14) 1 p(F3A) = pps(1 -pts)7 (6 3.15) p(F38) = p(F3A)
(63.16) 4 p(F3C) = I (30!)/[i!(30-i)!] (prs)i (1 - prs)3Si (63.17) i=1 p(F3D) = p(F3C)
(63.18) 8 p(F4A) = I(8!)/[i!(8-1)!] (prs)i (1 - prs)8-i (63.19) i=2 p(F4B) = p(F4A)
(6 3.20) 9 (6 3.21) i p(F4C) = I (30!)/[i!(30-i)!] (prs)I (1 - prs)3&i I
t=5 p(F4D) = p(F4C)
(63.22) p(F5C) = 30(30!)/[i!(30-1)!] (prs)i (1 - prs)3Si (6333)
I i=10 p(F5D) = p(F5C)
(6 3.24) 1 The values of probability of failure for p(FOA), p(FIA), etc. evaluated at f
different earthquake levels are listed in Table 6-5 for the base case, in which it was assumed that the upgrade for buildings C-331 and C-335 has been completed, and in Table 6-6 for the case where the upgrades are assumed to j
not be completed.
a
i i
Table 6-5. Fragility Characteristic for Basic Damage States Earthquake 0.05 to 0.13 0.13 to 0.21 0.21 to 0.29 0.29 to 037 037 to 0.45 f
{
Interval (g)
Median '
O.09 0.17 0.25 0.33 0.41 Earthquake (g)
Earthquake 1.05x10-2 335x10-3 9.80x104 2.90x104 2.00x104 probability (/yr)
Dama5e Level Conditional Probability of Damage Level p(FOA) 0.6598 0.1313 0.0045 0.0000 0.CCCO p(F0B) 0.6598 0.1313 0.0045 0.0000 0.CCCC j
p(FOC) 0.6598 0.1158 0.0000 0.0000 0.0CCO p(F0D) 0.6598 0.1158 0.0000 0.0000 0.00C0 p(FOT) 0.9868 0.8081 0.5000 0.2731 0.14 1 p(FIA) 0.3270 0.6321 0.1174 0.0005 0.CCCO 1
p(FIB) 0.3270 0.6321 0.1174 0.0005 0.0CCO p(FIC) 03270 0.5574 0.0024 0.0000 0.00C0 p(FID) 03270 0.5574 0.0024 0.0000 0.0CCO p(F1T) 0.0132 0.2009 0.5000 0.7269 0.S559 p(F2A) 0.0132 0.1919 0.1219 0.0012 0.0CCO p(F2B) 0.0132 0.1919 0.1219 0.0012 0.00C0 j
p(F2C) 0.0132 0.1692 0.0025 0.0000 0.000 p(F2D) 0.0132 0.1692 0.0025 0.0000 0.000 p(F3A) 0.0000 0.0438
- 0.3764 0.0167 0.00C0 P(F3B) 0.0000 0.0438 03764 0.0167 0.0000 p(F3C) 0.0000 0.1576 0.4483 0.0000 0.0C00 p(F3D) 0.0000 0.1576 0.4483 0.0000 0.00C0 P(F4A) 0.0000 0.0009 03798 0.9816 1.0000 p(F4B) 0.0000 0.0009 03798 0.9816 1.0000 p(F4C) 0.0000 0.0000 0.5305 0.0052 0.0000 p(F4D) 0.0000 0.0000 0.5305 0.0052 0.0000 p(F5C) 0.0000 0.0000 0.0161 0.9948 1.0000 p(F5D) 0.0000 0.0000 0.0161 0.9948 1.00C0 24
l l-l Table 6-6. Fragility Characteristic for Basic Damage States -
(Buildings C-331 and C-335 Unmodified) l Earthquake 0.05 to 0.13 0.13 to 0.21 0.21 to 0.29 0.29 to 037 037 to 0.45 l
Interval (g) l' Median 0.09 0.17 0.25 0.33 0.41 Earthquake (g)
Earthquake 1.0Sx10-2 3.35x10-3 9.80x104 2.90x104 2.00x104 probability (/yr)
DamaSe Level Conditional Probability of Damage Level
{
p(F0A) 0.0990 0.0000 0.0000 0.0000-0.00C0 p(FOB) 0.0990 0.0000 0.0000 0.0000 0.00C0 p(FOC) 0.6598 0.1158 0.0000 0.0000 0.0000 p(F0D) 0.6598 0.1158 0.0000 0.0000 0.00C0 p(F0T) 0.9868 0.8081 0.5000 0.2731 0.1411 p(FIA) 0.0491 0.0000 0.0000 0.0000 0.00C0
{
p(FIB) 0.0491 0.0000 0.0000 0.0000 0.0000 p(FIC) 03270 0.5574 0.0024 0.0000 0.0000 i
p(FID) 03270 0.5574 0.0024 0.0000 0.0000 p(FIT) 0.0132 0.2009 0.5000 0.7269 0.8559 i
l p(F2A) 0.0020 0.0000 0.0000 0.0000 0.00C0 p(F2B) 0.0020 0.0000 0.0000 0.0000 0.0000 p(F2C) 0.0132 0.1692 0.0025 0.0000 0.00C0 p(F2D) 0.0132 0.1692 0.0025 0.0000 0.0000 p(F3A) 03212 0.0000 0.0000 0.0000 0.0000 p(F3B) 03212 0.0000 0.0000 0.0000 0.0000 p(F3C) 0.0000 0.1576 0.4483 0.0000 0.00C0 p(F3D) 0.0000 0.1576 0.4483 0.0000 0.0000 p(F1A) 0.5288 1.0000 1.0000 1.0000 1.0000 p(74B) 0.5288 1.0000 1.0000 1.0000 1.0000 p(F4C) 0.0000 0.0000 0.5305 0.0052 0.0000 p(F4D) 0.0000 0.0000 0.5305 0.0052 +
0.0000 p(FSC) 0.0000 0.0000 0.0161 0.9948 1.0000 p(F5D) 0.0000 0.0000 0.0161 0.9948 1.0000 t
l l
25
~
Comparison of the values in these two tables shows that the only values that change are tho:e that include buildings C-331 (identier A) and C-335 (identifier B), consistent with the planned upgrading.
In general, the unconditional probability of a particular failure P is obtained by a convolution of the seismic hazard curve (presented in Figure 5-1) and the fragility curve, pr(a), for the particular mode of failure:
P = -f[ dH(a)/da ](pr(a)) da (6.4) 0 For the model developed for the damage levels of the PGDP, pr(a) can be any j
of the 1,800 combinations of the 24 basic damage states (FOA), p(F1A), etc.,
identified by Equation 6.3.1 to 6.3.24. For example, pp(a) would be represented by p(F3A)p(F3B)p(FOC)p(F0D)p(F0T) for the combination in which both buildings A and B suffer a level 3 damage, with no damage to buildings C and D or the tie-line structures.
In practice, the convolution integral is usually solved by a numerical solution that approximates the integral by the summation of a series of finite and discrete terms:
N P = I [H(ai.1) - H(ai)] [pr((ai.i + ai)/2)]
(6.5) i1 where a and a are, respectively, the lower-bound and upper-bound cutoffs o
s of the earthquakes to be considered in the risk study. For the current study, the values chosen for a and a were, respectively,0.05 g and 0.45 g. The o
s earthquakes between a and a were divided into five intervals (i.e., N=5). An o
s earthquake of 0.05 g was chosen as the lower-bound cutoff because practically no failure of structures or equipment is expected below this earthquake level at the PGDP site. The upper-bound cutoff 0.45 g was considered a reasonable choice because it is equal to three times the design / evaluation basis F
earthquake (0.15 g), and has a very low probability of exceedance in accordance 4
with Figure 5-1, i.e., about 2.7x10 per year.
Although large uncertainties exist in the hazard curve and the conditional probabilities of failure, they were judged to be less than those in the release for a given damage state. Therefore, only the mean values have been used in the interest of simplifying the calculations. This permits Equation 6.5 to be evaluated deterministically to obtain the values listed in Table 6-7. The values shown in Table 6-7 are for the purpose of comparing the modified and unmodified probabilities of various damage states. These values were never computed in the risk calculation, but are effectively embedded in the convolution integral, Equation 6.5. The probabilities in Table 6-7 are the result of multiplying the probability of an earthquake in a specified g level by the probability of damage, given the g level and taking the sum of all g levels.
26
l The probioilities change only for those damage levels for C-331 and C-335 (identido A and 6 in the Table 6.7), because they are the only buildings being upgraded. The table shows that the upgraded buildings are more likely to be in the low-damage-state levels than the non-upgraded buildings. The probability of damage in the large buildings is unchanged.
Table 6-7. Probability of Damage Level for Upgraded and Non-Upgraded C-331/C-335 Buildings Damage C-331/C 335 C331/C-335 Not Level Upgraded Upgraded j
p(F0A) 0.0148917 0.0021881 p(F0B) 0.0148917 0.0021881 p(FOC) 0.0148523 0.0148523 p(F0D) 0.0148523 0.0148523 p(FOT) 0.0241679 0.0241679 p(FIA)
' O.0087859 0.0010852 p(F1B) 0.0087859 0.0010852 p(FIC) 0.0085259 0.0085259 p(F1D) 0.0085259 0.0085259 p(FIT) 0.0014846 0.0014846 1
p(F2A) 0.0008289 0.0000442 l
p(F2B) 0.0008289 0.0000442 p(F2C) 0.0006872 0.0006872
)
p(F2D) 0.0006872 0.0006872 p(F3A) 0.0003860 0.0070992 p(F3B) 0.0003860 0.0070992 p(F3C) 0.0006987 0.0006987 p(F3D) 0.0006987 0.0006987 p(F4A) 0.0007400 0.0152171 p(F4B) 0.0007400 0.0152171 p(F4C) 0.0003946 0.0003946 p(F4D) 0.0003946 0.0003946 p(F5C) 0.0004727 0.0004727 p(F5D) 0.0004727 0.0004727 27
7.
Source Terms and Transport of Released Material 7.1 Source Terms The leakage of material and the transport from damaged cells, buildings, and debris is even more complex and varied than the possible damage states. The approach taken to simplify this risk analysis without sacrificing completeness is explained in this section. The selection of damage states discussed in Section 6 was based partially on the desire to include the full range of potential UF6 releases while maintaining a connection to the estimates ei realistic failure modes of the equipment and buildings. Similarly, the assignment of source terms to the set of 13 damage levels was also influenced by the need to address the full spectrum of possible consequences with a limited set of release categones.
The first major simplification made in the source terms was to model the entire complex of four buildings as a single point source for released ma:erial, ignoring any explicit modeling of individual building effects. For example, details, such as the fact that releases within the building experience greater mitigation than releases to open space, were incorporated in the judgment used to establish the probability distribution parameters. In the cases where releases occur from multiple building complexes, the releases were added to form a single source term.
The second major simplification is that the thermodynamics associated with the UF mixing with the moist air were assumed to have occurred prior to 6
i computing the transport of material away from the building complexes. Thus, ~
the transport calculations assumed that the material being transported is a stable mixture of HF and UO F, the products from UF reactions with moist 22 6
air. These products are the principle hazardous materials that impact human health and the environment. The fact that large, rapid mass releases result in higher-temperature plumes than small mass releases, and thus have greater buoyancy, was accounted for. The approach is discussed in Section 7.2.
The simplifications were necessary to make the analysis tractable, and are justified by the fact that the uncertainty in the mass of the released material is large, even when all the factors influencing the release are known. Thus, the selection of the uncertainty assigned to the source terms can be made with the intent to not only cover the uncertainty in leakage phenomena, but to take into account the approximations in the release and transport models. Based on this approach, the source terms associated with the six basic damage states, and the basis for selecting their uncertainty, are discussed. All source terms are modeled using truncated log normal distributions. This distribution covers the variable from zero to a finite cutoff that has been selected based on a judgment concerning the physically realizable upper bound for the damage 28
category. The distribution and cutoffs were selected to adequately cover wide uncertainty in the magnitude of the releases. Table 7-1 lists the mean and standard deviations for the basic release distributions.
j Weak Links in Process Boundary The damage associated with unidentified weak hnks in the probess boundary equipment is thought to be crack-type openings that would lead to air-in leakage. The resulting reaction of moist air and UF would provide the 6
pansient pressure to drive some material out of the system into the building, where it would then be exhausted. Some fraction could be expected to be contained within the duct work, and therefore not all released material would be exhausted. The amount of material leaked from a single damage location would be small, but there might be several such damage locations throughout the building. Calculated estimates of leakage from this type of 2
situation (presented in Refs. 8 and 9) support an assumption that 1% of the contained inventory is released from the building over several hours.
i Bellows Cracks The mode of leakage for this type of failure is similar to that discussed in the case of " weak links." The bellows failures are more likely to be associated with earthquakes beyond their design capacity, however, and the failures, although they may be fewer in number than in the case of " weak links," would be expected to result in greater amounts of material released to the building because of the formation of larger openings. Since the failure is associated with higher-level earthquakes, it is likely that building panels or duct work may be damaged, creating direct routes for release from the building. It was assumed that 2% of the contained inventory could be released, over several hours, from this category of failure.
Tie-Line Collapse This category of failure accounts for the possibility of the tie-line structures failing at higher earthquake levels. This would lead to gross failure of the piping, and formation of an opening into at least one building's process system. A major fraction of the material contained in the pipes would be released, plus some of the contents of the connected process system. The release would likely occur over a short period of time. It is assumed to involve more than one tie-line structure. Ref. 8 estimated that 1,000 pounds of material might be released from a single tie-line failure. This amcunt was doubled to account for the possibility of more than one structure failing. The uncertainty accounts for the fact that all of these structures may fail.
29
Single Building Unit Collapse The release under this failure condition is intended to represent the many possibilities of some of the buildings in a complex failing, along with associated piping system failures. Both the material of the collapsed building, plus that of the adjacent buildings, would make major contributions to the release. Material that is far from the point of major damage would be released slowly, and therefore was not included. The release would consist of a large fraction released in a short period of time, followed by continued release over many hours, even days.
The collapse can occur in a variety of ways, and each will have some impact on the magnitude of the release. For example, if the roof falls onto the operating floor, which then falls to the first floor, considerable debris will be
{
piled on the equipment, which could mitigate the release. However, if the equipment floor falls without severe damage to the roof, the character of the release would likely be different. This variability is intended to be captured in the selection of the parameters for the release distribution. The inventory distribution shown in Figure 3-2 was considered. A judgment was made based on one of the buildings in each complex collapsing and releasing approximately 1/2 of one of the unit's material, plus approximately 1/4 of the material of the adjacent units. The values were rounded to those shown in i
Table 7-1. A standard deviation was selected on the basis of reviewing the form of the lognormal distribution as a function of the standard deviation.
The Crystal Ball program facilitates selection with graphical presentation of the distribution. The standard deviation was selected to achieve release possibilities that are consistent with the envisioned level of damage and the inventories involved.
Two to Ten Building Units Collapse This damage level is intended to apply to the most severe situation for buildings C-331 and C-335, while in the case of C-333 and C-337 it is an intermediate damage level. The postulated release was established by considering 1/2 the material of the collapsed units plus 1/4 of the material of the adjacent units. Multiple configurations can be envisioned. Each of these was considered, and a release level was selected to represent a range of conditions that might be realized with the more severe damage. The standard deviation was developed as described above for the single-unit collapse. In the case of C-331 and C-335, this case represents the upper limit of the release possibilities.
Ten or More Building Units Collapse The process described above was repeated for the ten-unit collapse envisioned for the C-333 and C-337 building complex. This damage level, like the two-unit damage level in C-331 and C-335, was envisioned to open the entire 30
piping complex to direct release. If more than 10 units were to collapse, the probability of mass release would be similar to the probability assumed for the ten damaged units. There is a large variability in the magnitude of the release that might occur with this extensive damage, and the parameters for the release were selected to reflect this variability.
The source terms in Table 7-1 were used to compute the releases for all combinations of damage states. For example, the release from a damage state that includes tie-line breaks and weak link failures in all buildings would be computed as follows: the mass that results from sampling the tie-line distribution would be added to the results from sampling each of the four distributions for weak links. Thus, the released mass for a particular damage state would vary with each trial. There may be trials in which the released mass trom what is presumed to be a more severe damage state is less than the released mass for a more benign damage state.
7.2 Transport of Released Material Six unit source terms for input to the atmospheric transport calculations were developed based on the six release categories identified in Section 7.1. These source terms were selected to cover the range of releases in Table 7-1 and to produce downwind release concentrations for use in the risk calculations.
The amount of material released in a specific trial is determined by sampling the distributions in Table 7-1. (Metric units were used in Table 7-2 because they are consistent with the units used in the calculation. English units were used in Table 7-1 to be consistent with Figure 3-2.) Based on the total amount released, the appropriate unit source term is selected.
Table 7-2 lists values of UF mass and mass release rates used to calculate the
~
6 initial conditions entered into the transport calculations. Atmospheric release rates, Mo(uf6)(kg/s), calculated as the mass of UF released divided by the 6
release duration (assumed to be 300 s ), are also shown in Table 7-2.
For source numbers 1 and 2, the difference between the plume temperature at the point of release and the ambient air temperature (AT) was assumed to be 22.2 C (40 F); for sources 4,5, and 6, AT was assumed to be 44.4 C (80 *F); and for source 3, AT was assumed to be zero. The ambient temperature and relative humidity-assumed to be 21.1 C (70 *F) and 70%, respectively-are a representative temperature and relative humidity at PGDP for the stability classes and wind speeds analyzed (see below). Plume temperatures, T (K), at p
the exit vent are listed in Table 7-2.
)
31 r
Table 7-1. Basic Released Masses, LoS Normal Distribution Damage Description Mean Value of Mass of UF.
Standard Deviation Released, Ib.
- 1. Weak links in process 1% of mass contained in 1% of mass contained in boundary building building C-331=500 C-331=500 C-335=750 C-335=750 C-333=3,200 C-333=3,200 C-337=4.500 C-337=4,500
- 2. Bellows cracks 2% of mass contained in 2% of mass containedin building building C-331=1.000 C-331=1,000 C-335=1,500 C-335=1,500 C-333=10,400 C-333=10,400 C-337=9,000 C-337=9,000
- 3. Tie-line collapse 2,000 1,000
- 4. Single building unit C-331=12,000 C-331=5,000 collapse C-335=19,000 C-335=5,000 C-333=30,000 C-333=10,000 3
C-337=30,000 C-337=10,000
- 5. 2-5 building units collapse C-331=15,000 C-331=10,000 C-335=22,000 C-335=10,000 C-333=70,000 C-333=10,000 C-337=60,000 C-337=10,000 6.10 ormore building units C-333=170,000 C-333=50,000 collapse C-337=150,000 C-337=50,000 1
Table 7-2. Source Conditions used to Compute X/Qs Source Mass Mows T (K)
Mom Mown Mo MW Vo Fo p
p No.
Released (kg/s)
(kg/s)
(kg/s)
(kg/s)
(kg/kgmol),
3 2
(m /s)
(m*/s )
(kg) 1 1,242 4.139 316.53 0.42 40.31 44.88 58.65 19.873 4.353 2
2,483 8.278 316.53 0.85 80.63 89.75 58.65 39.746 S707 3
454 1.512 294.31 0.15
. 14.73 16.39 58.65 6.750 0 000 4
10,320 34.398 338.76 3.52 335.02 372.94 58.65 176.751 7'.355 5
18,938 63.126 338.76 6.46 614.83 684.41 58.65 324.367 132333 6-72,575 241.918 338.76 24.74 2,356.22 2,622.88 58.65 1,243.084 508.371 32
1 The total plume mass flux, Mo (kg/s), was calculated assuming that the i
amount of air in the plume contained just enough water vapor to completely react with the UF to form UO F and HF. Assuming stochiometric 6
22 proportions,2 moles of water vapor per mole of UF are needed for complete 6
reaction. Therefore, the mass flux of water vapor, Mo(h2o) (kg/s), in the plume would be l
Mom = Mo(we x (2MW,/MW )
u g
i where MWh2o is the molecular weight of water vapor (18.001 kg/kgmol), and MWuf6 s the molecular weight of UF (332.02 kg/kgmol). The mass flux of dry i
6 air in the plume, Mo(air) (kg/s), is equal to Mo(h2c) divided by the mass ratio s
of water vapor to dry air, r. At 21 C and 70% relative humidity, rm is about m
0.0105. The total mass flux is simply given as:
M = M <gy +Mocu,3+M,in o
o ot Once Mo has been calculated, the molecular weight of the plume, MWp (kg/kgmol), at the assumed release point is given by:
MW = MWuf6 x(Mo(uf6)/Mo )+MWh20x(Mo(h2o) /Mo )+MW,irx(Mo<,in/Mo) p Values of Mo(h2o), Mo(air), Mo, and MWp are given in Table 7-2 for sources I through 6.
Assuming the plume behaves like an ideal gas as it exits the building or debris, the volume flux, Vo (m3/s), at the release point is given by:
Vo = MORT /MW p p
p where R is the ideal gas law constant (0.08206 arm-m3/kgmol-K), and p is atmospheric pressure (assumed to be I atm).
To determine plume rise, the buoyancy flux, Fo (m /s3), of the plume at the 4
exit was calculated using an expression developed by Briggs (Ref. 23):
Fo = g/n (ATVo/T )
p Plume rise may also be determined using the plume momentum flux, Fm; however, Fm was not used to determine plume rise for this analysis. Based on preliminary screening calculations, this is a conservative assumption (i.e.,
results in higher downwind consequence estimates) because Fm would be greater than Fo, resulting in higher plume rise estimates for all release scenarios. Values for Fo are shown in Table 7-2.
For sources 1,2,4,5 and 6, the release was assumed to occur from a point source located between all of the process buildings at a height of 25.15 m (82.51 ft-i.e., flush with roof of Bldg. C-337). For source 3, the release was assumed 33
i
)
i to occur from a point source located midway along the tie line connecting Bldg. C-335 with Bldg. C-337 at a height of 11.66 m (38.25 ft-i.e., the height of the tie line). The effective building width input into the model for wake calculations was assumed to be the maximum diagonal width connecting the southwest corner of Bldg. C-335 with the northeast corner of building C-337.
This width is about 644 m (2,116 ft).
Twenty-four meteorological conditions were simulated for each release scenario to account for the possible conditions that could occur at PGDP (Ref.
26). The stability classes (Pasquill A, B,C, etc.) and wind speeds (m/s) categories calculated were as follows: A-1,2, and 4; B-1,2,4, and 7; C-1,2,4,7, and 10; D-1, 2,4,7, and 10; E-1,2,4, and 7; and F-1,2, and 4.
Uranium dispersion factors, designated X/Q (where X is the downwind concentration and Q is the rate of U release) were calculated for sources 1 through 6 using the WAKE dispersion model (Ref. 26). The WAKE model is part of the HGSYSTEM/UF6 suite of codes used to simulate atmospheric dispersion, thermodynamics, and chemical reaction of UF releases. A 6
primary assumption in the application of the WAKE model to the PGDP process buildings, is that all chemical reactions are comple'ced before release to the atmosphere for transport. Therefore, the reaction products (UO:F: and HF) are dispersed as non-reactive, but warm, gases, and atmospheric chemical reactions can be ignored. Values of X/Q were calculated at the site boundary located 900m (0.56 mile) north of Bldg. C-337, and downwind distances of 1,610 m (1 mile),3,220 m (2 miles),8,050 m (5 miles), and 16,100 m (10 miles).
These X/Q values, tabulated in Appendix B, were used to determine HF exposure and uranium uptake in the risk calculation.
Uranium uptake, U (mg), may be calculated from the X/Q values using the following equation:
U = X/Q x mu /T x BR x Texp d
where:
muis the mass of uranium released (mg) to the atmosphere, Ta is the duration of the release (seconds),
3 BR is the breathing rate (m /s), (0.000417 m3/s is the value used in the risk calculation based on the Ref. 25 recommended value for light exercise),
and Texp is the exposure time (s).
The WAKE model calculates Texp based on the meteorological conditions and the receptor downwind distance with a different Texp for every X/Q value.
However, constant values for exposure times are used in the risk model, along with the X/Qs from Appendix B. At receptor locations relatively close 34
._=
to the release point (the site boundary and 1 mile downwind), exposure times muy be relatively short (less than 1,000 s). At longer distances (2 miles or greater downwind), exposure times are relatively long (about 1,500 s or greater). Using fixed values of Texp introduces some error into the calculations, with uranium uptake being overestimated for exposure times less than 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> (note that the maximum time was limited to I hour).
However, for receptor locations 2 miles or greater downwind with relatively long exposure times, the error in the uranium uptake calculations would be small.
HF concentrations, Cup (mg/m ), have been calculated from the X/Q values 3
presented in Appendix B using the following equation:
Cap = X/Q x mu/Ta x 4MW r/MWu h
where MW ris the molecular weight of HF (20.006 kg/kgmol), and MW is h
u the molecular weight of the uranium (238.029).
35
l l
8.
Population Distribution and Emergency Response l
8.1 Population Distribution
^
The population of workers on site and the in the vicinity of the PGDP was i
obtained from the Final Safety Analysis Report (Ref. 2). The population is shown to be quite stable and the distribution estimated for the year 2000 was l
selected for use in this study. The daytime population distribution shown in Figure 8-1 was assumed to be the total population and included all the workers. ( This an approximation because many plant workers come from l
areas beyond the five mile radius.) This population distribution was used with modifications to account for the following two factors: (1) workers moving from off-site to on-site during the day and reve. ming this distribution j
at night; and (2) transient recreational population in the near vicinity of the site that was reported in Ref. 2 but not included in the distribution shown for the year 2000.
l Both the daytime and the nighttime population distributions were used in the risk calculation. The daytime distribution was derived from the total l
population by subtracting 2,000 people from sectors with high population densides and placing them uniformly distributed on site. It was assumed that 300 people remained on-site at night, and therefore 1,700 people were added l
back into the off-site distribution to obtain the nighttime distribution. An l
equal chance of earthquakes occurring at night or during the day was also assumed, and therefore the two populations were sampled with a fifty percent chance of getting one or the other on a specific trial.
i The largest transient usage appears to be recreational, characterized as follows:
Picking berries; hiking; and holding church, school, or club events on the property (estimates of 35,000 to 50,000 or more such trips annually).
Fishing, primarily in the spring and fall (5,000 trips annually).
Small game hunting September through January, primarily in the fall, l
and dog training September through March (2,600 use-days annually).
l l
Field trials for dogs on weekends from October through December 15 and from January 15 through March (1,000 to 1,500 participants).
l Bow hunting of deer October through January 15 (2,800 trips).
I Gun hunting of deer three weekends from October through December (600 trips).
Overnight camping, primarily in the fall, associated with deer hunting, at
" primitive" sites that have no facilities (300 use-ni-hts).
Bird-watching (50 use-days annually).
36
_ _ _ _ _ _ _ _ _ _ _ _ _ _. ~
He,seback riding (300 trips annually).
Spreading these visits over the year and attributing the primitive site camping to both day and night usage, these recreational usage figures correspond to an additional 155 average day-users and I average night-user present between one and two miles from the center of the plant site. When this is divided among the 16 directional sectors, it contributes an additional 13 average day-users between one and two miles from the plant site.
1 8.2 Emergency Response Under emergency conditions other than earthquakes, the off-site emergency l
response team can be expected to contact the majority of the population who might be affected and happen to be near communications devices. Tne current plan calls for appropriate authorities to be contacted within' fifteen minutes of the start of an event. Nasal or dermal irritation and a visual plume will also cause people to seek protection themselves. The response of the population near the plant boundary may not be as timely, especir3y at night. But for those people further than one mile from the plant boundary during the day, the exposure should be minimal.
Although adequate action plans are in place to reduce the exposure of on-site personnel to a minimum, it is somewhat questionable what could be done in the case of an earthquake, and how well the on-site event detection system would work. The PGDP SAR identifies only three types of real-time alarm systems: process control alarms (many), criticality alarms (sufficient), and smoke detector alarms, which are primarily near the autoclaves. A portion of
~
1 the site population is trained to gain protection from releases, and, therefore, could be expected to respond in a manner to reduce injuries.
I i
i i
I 37 a.
j'gge]qis*4)ll Fiu W
\\
S ctor l'olitilali""
11oute 45 Year = 230 25
~
a stos 110 51 24 0
North 27 2480 r, *.
66 16 62 j
.f.
04fo pf,'C 44 3
25 71 T
0 0
I1
/
0 52 28 0
o 4s ss 80 e2
/
o d
0 0
0 0
52 g mg /*
148
+ /,
85 169 112 1
3g 0
26 7gy 19 121 2M 106 34 40 229 III 8 'ai 63 242 120 202 Itoute 60 4 ml 70 gao 59
,,,, Paducah 11eservation Boundry 3,o Figure 8-1. Projected Daytime Population Distribution at the PGDP Site in Year 2000 1
=
38
- w g
y' c+p4,..
y.
m w
w T
v
)
j i
9.
Health Consequences The health consequences from exposure to HF and to UO2F, the principle 2
products of reaction of UF with moist air, are well studied and documented 6
(Refs. 27,28 and 29). This section summarizes the information to provide a 1
data base for the discussion of risk. The hazard of HF, which is discussed first, i
is used as a reference for comparing the risks at the PGDP to the risk associated with industrial use of HF. The hazard of UO F is unique to the 22 nuclear fuel industry, and therefore is not directly comparable to other industries. Both compounds introduce fluoride ions into the body, which can have a toxic effect in high concentrations. Refs. 27 and 28 show that, for these compounds, the toxic effect of uranium and HF dominate the potential toxic j
effects of the fluoride ion, and therefore, its effects can be ignored.
9.1 Hydrogen Fluoride
]
Hydrogen fluoride is identified by the EPA as an extremely hazardous substance (EHS), with a threshold planning quantity of 100 pounds, under Section 302 of the Emergency Planning and Community Right-to-Know Act.
This substaue is classified as both toxic and corrosive in regulations. Table 9-1 from Ref. 28 summarizes the health hazards from a range of HF aqueous j,
concentrations.
Although this table provides a reasonably precise measure of the hazard,it is difficult to apply these values to a risk assessment. The period of time a person is exposed to these concentrations will impact the damage experienced. For example, a short period of eye irritation may represent no harm, while a lengthy period may lead to permanent eye damage. Tne accidental release from a PGDP facility is anticipated to be to the atmosphere, and therefore the concentrations given in Table 9-1 are not directly applicable.
Table 9-1. Health Hazards from Exposure to HF Aqueous Concentration by Indication of Associated i
Weight (%)
Danger Risk Phrases 0.1% 1C<1%
Harmful Harmful by inhalation in contact with skin and if swallowed. Irritating to eyes.
1% s C < 7%
Toxic corrosive Toxic by inhalation, and in contact with the skin and if swallowed. Causes burns.
C2.7%
Very toxic corrosive Very toxic by inhalation, in contact with skin and if swallowed. Causes severe burns.
i 1
39 w
i The Pacific Northwest Laboratory recently completed an assessment of the health risks from exposure to UF (Ref. 27). The section of the Ref. 27 report 6
that assesses the HF hazard identifies various concentration levels used in safety and health standards and concentrations that produce physically noticeable effects. These are listed in Table 9-2.
1 For HF exposure to result in measurable harm, the concentrations would have to be above 30 ppm. Concentrations of 50 ppm for one hour or more might be expected to produce measurable damage.
i l
Table 9-2. Significant HF Concentrations in Air HF Concentration in Physical Effect or i
Air, ppm Standard Usage 0.04 to 0.13 Odor threshold for humans l
3 TLV recommended by the ACCIH and also the PEL-TWA from OSHA 5
AIHA EPRG-1 to avoid objectionable odor and other than mild irritation from 1-hour exposure 30 IDLH identified by NIOSH and also used in NUREG 1391 as having no significant effect short orlong term 48 AIHA EPRG-3 no life-threatening health effects from 1-hour exposure 122 1-min. exposure can cause severe irritation of the nose, throat, and respiratory tract 1
1,264 LC f
50 or rats with 1-hour exposure 9.2 Uranium Oxyfluoride As mentioned above, the toxic effect of the uranium is the factor of greatest concern from the release of the UO F compound. The dominant toxic effect 22 of uranium is damage to the kidney tissues, which destroys the kidneys' ability to remove damaging chemicals from the body. There are potentially damaging effects to the vascular and nervous system, but these effects are overshadowed by the kidney damage. Table 9-3 from Ref. 29 summarizes the health effects of uranium.
40
y Table 9-3. Health Effects From Intake of Soluble Uranium 2
Uranium,mg per i
Uranium Uraniumin kg of Body Intake, mg Person, mg Weight Health Effect 4.3 2.1 0.03 No effect 8.3 4.06 0.058 Threshold for transient kidney inju y 40 21 0.3 Threshold for permanent kidney damage
+
230 114 1.63 50% lethality i
Ref. 28 explains the meaning of transient kidney injury as follows:
"The renal [ kidney] injury or effect threshold of 0.058 mg-U/kg is the level at which one or more of the chemical components of the urine indicates that there has been some change to some structure within the
{
kidney. The chemical changes at the threshold level have been found to be transient, with the chemical composition of the urine soon returning to normal. Microscopic examination of the kidney would detect no damage several weeks after the exposure."
The same reference calculates that 5,000 mg of 4% enriched uranium would have to be inhaled to produce a dose equivalent of 25 rem. Based on the fact that a single 25 rem dose (5,000 mg) of radiation produces no measurable health effect, but several tens of mgs may cause chemical damage, the chemical hazard of low enriched uranium at the PGDP is seen to far exceed the radiation hazard.
9.3 Cloud of Mixed Material It is reasonable to expect that the cloud of released material will contain both hazardous materials (UF and HF). One kg of UF contains 0.68 kg of uranium 6
6 and 0.32 kg of fluoride ions. The reaction of UF with moist air results in 0.23 6
kg of HF. Assuming that this ratio of components remains constant throughout the period of exposure, a 30 minute exposure to a cloud containing 25 mg/m3 of HF would result in inhalation of 31 mg of uranium-close to the 40-mg threshold for transient effects from uranium exposure to be observed. Thus, under these assumptions neither chemical would produce permanent injury. Both are approaching thresholds where transient effects are noticeable.
- If the exposure is increased by a factor of ten (assume 125 mg/m3 of HF for I hour), an individual would experience severe irritation of tne eyes and
- Intake is defined as the total amount inhid into the body. It includes material immediately exhaled in addition to material retained by the body.
41
i respirator However,y passages, and possible permanent he.alth damage from the HF.
the effects of the uranium (inhalation of 310 mg under this 1
assumption) could be lethal, and would certainly lead to permanent kidney damage.
Because the HF is a gas and the UO F is a solid particle, natural mitigation 22 effects could cause the two materials to separate such that a stochiometric mixture is not present. Mechanisms to reduce the release of the HF gas may be less effective than those available to remove the solid particles of UO2 2 If F
this were true, the concentration of uranium contained in clouds would be lower than the concentration of HF, and therefore the ratio of HF to UO-F2 would be greater than assumed in the above estimates. To produce a cloud that has approximately the same lethality from both materials requires that the uranium-to-HF ratio be reduced by a factor of 3 to 4 from a stochiometric mixture.
As shown above, both materials could be present in the cloud at hazardous i
levels. Information on the relative concentrations of the two materials in released clouds, or on the possible synergistic effects of simultaneous
{
exposure to both hazardous materials, was not found. The two materials are
{
therefore considered separately in the risk calculations, and the HF consequences and risks are compared to those associated with other industrial uses of UF.
6 i
i I
i 42 5
10.
Calculation of Risks Risk is characterized as a function of consequences and probability of occurrence. fn the case of human health risks, the consequences considered may be the occurrence of a disease, such as cancer, or injury or death. The consequences that might be observed in the case of an accidental release of UF are injuries, such as damaged kidneys, damaged respiratory organs, 6
vision damage, and possibly death. Injuries may be permanent or temporary.
Temporary injuries are those that disappear following a short period of discomfort or abnormal responses in body chemistry. Other consequences, such as property damage and land contamination, have not been considered in this study, because they do not directly impact health and are likely to be confined to the PGDP site, even in the more severe cases.
Calculating the consequences from the released material requires the computation of the airborne concentrations and the time period of exposure of a specific number of people. In addition, it is necessary to translate the exposures into health consequence categories. Based on the information in Section 8 concerning the health effects, consequence thresholds have been established for use in the risk calculation. Table 10-1 lists the selected values.
l Table 10-1. Consequence Thresholds Used in Calculating Risk
\\
Consecgnce Exposure Threshold 1
3 Noinjury HF<50mg/m and U intake < 30 mg 3
3 Injury 50 mg/m < HF < 500 mg/m or30 mg < U Intake C0 mg 3
Fatality HF > 500 mg/m or Uintake > 300 mg The category " temporary injury" has not been included because inclusion of this category did not appear to improve the understanding of the risks, and it would not be consistent with approximations made elsewhere in the model.
Calculation of the specific number of people in any one trial that experience an exposure that results in one of the health effects in Table 10-1 proceeds as follows. The exposure of the population distributed along an azimuth as a function of distance (it is assumed that the wind continues to blow in the same direction over the period of the accident) is caluculated first. Then, based on the population in sectors along the azimuth, the number of people in each of the health effects categories in Table 10-1 is determined. This calculation is repeated typically 5000 times and the the number of outcomes in each consequence interval is accumulated. The number of trials with 43 w
results falling in specified consequence interval divided by the total number of trials is the probability of that specific outcome. The complementary cummulative distribution can be obtained by counting (summmg) the total number of outcomes above a specific value of injuries or deaths and dividing this number by the total number of trials.
To determine the exposure along a specific azimuth a specific damage state, release level, and diffusion parameter X/Q is required. A value is obtained for each of these factors each trial by randomly sampling their probability distributions. Given the damage levels identified in Section 6, there are 2 x 5 x 5 x 6 x 6=1,800 combinations of pos.sible damage states. Many of these are not reasonable. For example, having all buildings but one fail and that one i
remain undamaged is highly unlikely compared to other combinations. A simple rule was developed to exclude the very improbable damage states: all failure combinations are assumed to lie within a range of 3. That is, if a building had no damage then the greatest damage severity another building 1
could reasonably have would be two levels up from that. This rule resulted in reducing 1800 to a total of 464 combinations for the damage states. The probability of each of these damage states was computed, and a probability density function for the damage states was constructed and entered into the Crystal Ball program.
Similarly, the level of release was obtained by sampling the release distributions identified in Section 7 which are dependent on the damge level of specific buildings and equipment. The releases obtained from the sampling were added to obtain the source for that specific damage state. Thus, the same 4
damage state could result in a different release in each trial due to the uncertainty. The joint probability density function for the meteorological condition was sampled and the corresponding X/Q used to compute the exposure, and from the exposure and population determine the number of injuries and deaths for that trial. Typically,5,000 trials were run for each case, and the output from Crystal Ball provided the statistics.
4 Table 10-2 presents a summary set of statistics for the analysis case that used probabilities for damage states representative of buildings C-331 and C-335, seismic upgrades having been completed. In the following tables, this case is referred to as the " Upgrade" case. It was assumed that emergency actions were not effective and that 40% of the released uranium particulate was deposited in the damaged building. The number of fatalities was zero, and the number of cases with injury were distributed as shown in Table 10-2. The column of probabilities the probability density function (pdf). The complementary cummulative distribution, ccdf, can be computed from these numbers. Most of the trials produce no injuries. Only a few of the many trials recorded in injury interval "0-2" have 1 or 2 injuries; most are zero. The maximum number of injuries in any of the 5,000 trials was 192, which occurred in one trial. The fact that most cases produced no injuries was somewhat 44
unexpected, and the effectiveness of reporting the probabilities based on the few cases that had injuries can be questioned. The character of the distribution in Table 10-2.is typical of all cases, i.e., there i., an unevenness in the distribution that continues to exist even for runs that used 50,000 trials.
However, the means and standard deviation of the distribution did not chmge significantly when the number of trials increased beyond 5,000, so this number of trials was used to run all cases. In retrospect, more trials in each case would have been useful, but would not be expected to change the general shape of the distribution significantly.
Table 10-2. Statistics for Case with Seismic Upgrades and No Emergency Actions Injury Interval, Number of Trialsin Probability of Trial Ni InjuryInterval Being in Interval 0-2 4,977 0.9954 2-4 0
0.0000 4-8 12 0.0024 8-15 0
0.0000 15-18 0
0.0000 18-30 0
0.0000 30-40 1
0.0002 40-50 0
0.0000 50-60 1
0.0002 I
60-70 0
0.0000 70-90 0
0.0000 90-120 0
0.0000 120-130 6
0.0012 130-140 0
0.0000 140-150 0
0.0000 150-160 1
0.0002 160-170 0
0.0000 170-180 1
0.0002 180-190 0
0.0000 190-192 1
0.0002 The " Upgrade" case, along with analysis results from a case that used damage state probabilities representative of buildings C-331 and C-335 not being seismically upgraded ("No Upgrade"), are presented in Table 10-3. Table 10-3 condenses the results to a form that is consistent with Table 10-2, for the 45
" Upgrade" case. A similar output for "No Upgrade" case was also condensed-This condensation and format was selected because it appeared to present the comparisons better than the previous table format and in the form of a complementary cummulative distribution commonly used in risk assessment.
l Table 10-3. Comparison of the Case with No Seismic Upgrade to the Case with Seismic Upgrade Number ofInjuries, Probability perYear of the Number of Ni Injuries Being Greater than Ni UP5rade No Upgrade 1
0.0046 0.0054 8
0.0022 0.0038 60 0.0018 130 0.0006 0.0016 192 0.0000 0.0000 1
8 Because of the unevenness in the distribution no appropriate value is available for this case.
Seismic upgrading provides a small improvement in that it is somewhat less j
probable that injuries occur in this case. Both cases produced a maximum of 192 injures; however, there were two trials with this result in the "No l
Upgrade " case and only one trial outcome in the " Upgrade" case. The seismic upgrades may not have a risk reduction benefit for the public, due in a large part to the fact that the public will be affected only in the most severe earthquakes, which not only impact the C-331 and C-335 buildings being upgraded, but may produce much larger releases from the C-333 and C-337 buildings that contain the major inventory of UF.
6 These two cases were assessed to determine the extent of off-site versus on-site injuries. Table 10-4 provides comparison of the probability of off-site injuries for the two cases. The risk reduction from the seismic upgrade appears a little more beneficial from this comparison, but it is still a small improvement.
With reservation, a similar comparison for on-site injuries is provided in Table 10-5. The approximations used in the transport model, and lack of detail about the distribution of the on-site population, make these estimates very uncertain. One might even expect fatalities occurring on site in the more severe releases, but none were calculated, further emphasizing the crudeness of the on-site evaluations. In addition, it is very likely that on-site injuries will be caused by factors other than release of UF.
6 46
Farametric cases were run to evaluate the importance of emergency response to the reduction of risk. The results from these cases are provided in Table 10-6, where they are compared to the values from Table 10-3. These results are u
l Table 10-4. Comparison of Off-Site Injuries for the " Upgrade" and "No Upgrade" Cases Number ofInjuries, Probability per Year of the Number of Ni Injuries Being Creater than Ni UP5rade No UP5rade 1
0.0010 0.0022 30 0.0006 0.0008 90 0.0000 0.0006 175 0.0000 0.0000 Table 10-5. Comparison of On-Site Injuries for the " Upgrade" and "No Upgrade" Cases Number ofInjuries, Probability per Year of the Number of Ni Injuries Being Greater than Ni Upgrade No Upgrade 1
0.0046 0.0054 6
0.0018 0.0030 125 0.0000 0.0000 i
47
1 L
k Table 10-6. Comparison of the Cases with Emergency Response (ER) with Those Having no ER J
)
Numberof Probability per Year of the Number of Injuries l
Injuries, Ni Being Greater than Ni UP5rade No Upgrade No ER ER No ER ER i
1 0.0046 0.0028 0.0054 0.0050
}
8 0.0022 0.0038-0.0028 30 0.0004 0.0002 1
60 0.0018 0.0000 0.0000
{
1 i
130 0.0006 0.0016 i
192' O 0000 0.0000 8
Because of the unevenness in the distribution no appropriate value is available for this case.
i 4
]
somewhat erroneous because the 5,000 Monte Carlo trials were too few to i
provide adequate data in the cases where emergency response is used. The data indicate that the "No Upgrade" case, with emergency response, is lower in risk than the " Upgrade" case with emergency response, which is not i
l possible. Review of the detailed data indicates that the two emergency response cases are essentially the same, and this summary data provides only.
l a rough indication of that fact. Consideration was given to rerunning these i
cases to obtain more valid results, but their significance to the overall evaluation did not appear to warrant this effort. Effective emergency response can have a major impact on both on-site and off-site consequences. The simple models used in this analysis indicate a benefit, but the models are probably not reflecting the real potential for reducing injuries.
4 e
a h
48
,.. ~ _ _
11.
Comparison with Other Industrial Risks No other mdustry uses anywhere near the amount of uranium that is used in the nuclear fuel industry, and therefore the substantial inventory of uranium at a uranium enrichment facility is unique to the industry. However, several other industries are large users of HF, as well as chemicals with haza'rds similar to HF, such as chlorine and H SO. Therefore, a review of 2
4 information on these materials, with a focus on HF, was completed. The comparative size of the HF industry, and the uranium enrichment inventories at the PGDP, provide some perspective on their relative risks.
This comparison is reasonable because, although the uranium increases the hazard of the material released in an accAent at the PGDP, the increase is only a factor of two or three over that of HF by itself. There is the additional i
subjective concern that the name " uranium" adds to the perception of the hazard, but the information on the toxicity of uranium in Section 9 indicates that the chemical hazard is the dominant concern, and that the HF and uranium are approximately equal contributors to the hazard.
The hazards associated with the use of anhydrous H SO and chlorine gas are 2
4 also similar to, if somewhat less than, the HF hazard. (The mobility of the fluorine ion in HF causes more serious burns that are difficult to treat. ) These two chemicals are used in industry to a much larger extent than HF. Table 11-1 summarizes data from Ref. 30. Therefore, although they are less hazardous materials, they may present a greater overall risk to the public due to large quantities being transported and used.
Table 11-1. Production of Selected Chemicals With Hazard 2
Characteristics Similar to UF,T/yr 6
Hydrogen Fluoride 318,000 Chlorme 22,200,000 Sulfuric Acid 44,600,000 Accidental releases of these materials have occurred, both in transit and at the user facilities. The consequences of such accidents have included loss of life and serious injuries of workers. Public harm has generally been avoided by prompt emergency action, although serious environmental damage and major displacement of the population have occurred. Ref. 28 identifies incidents involving accidental release of Hr. Seven of the accidents each involved 1 or 2 workers being killed. The predicted consequences of a major 2 1 hey form clouds of corrosive gases.
49
i i
I
{
release of UF from the PGDP are similar to the consequences that have been 6
experienced from accidents involving these more commonly used chemicals.
There are only a few producers of HF, they are identified in Table 11-2 (Ref.
i 31). Their product is shipped by both truck and rail to the users in the i
chemical and petroleum processing centers of the US.
Several industries make extensive use of HF; at the top of the list are the producers of fluorocarbons. Table 11-3 (Ref.) lists the major categories of users, and shows that the nuclear industry's use, primarily to produce UF, is 6
noticeable, but does not constitute a large fraction.
Ref. 32 reports on a study of the probability of spills associated with shipping HF to four oil refiners in the 1.os Angeles area, where it is used in the alkylation of petroleum. The probabilities of spills estimated in the study are summarized in Table 11-4. These were based on 55 truck trips per year, of varying length, from the producers to the four refineries (plants A though D in the table).
l l
Table 11-2. U.S. HF Production Capacity Producer T/yr Allied-Signal 142,000 Du Pont 68,000 Atochem 22,000 Quunica Fluor 68,000 Fluorex 18,000 j
Total '
318,000 i
Table 11-3. Users of HF Production of Fluorocarbons 70 %
Nuclear Industry 4%
Alkylation Processes 5%
Steel Pickling 5%
Other Markets 16 %
50
release of UF from the PGDP are similar to the consequences that have been 6
experienced from accidents involving these more commonly used chemicam.
1 There are only a few producers of HF, they are identified in Table 11-2 (Ref.
31). Their product is shipped by both truck and rail to the users in the chemical and petroleum processing centers of the US.
Several industries make extensive use of HF; at the top of the list are the producers of fluorocarbons. Table 11-3 (Ref.) lists the major categories of users, and shows that the nuclear industry's use, primarily to produce UF, is 6
noticeable, but does not constitute a large fraction.
Ref. 32 reports on a study of the probability of spills associated with shipping HF to four oil refiners in the Los Angeles area, where it is used in the alkylation of petroleum. The probabilities of spills estimated in the study are summarized in Table 11-4. These were based on 55 truck trips per year, of varying length, from the producers to the four refineries (plants A though D in the table).
Table 11-2. U.S. HF Production Capacity Producer T/yr Allied-Signal 142,000 Du Pont 68,000 Atochem 22,000 Quunica Fluor 68,000 Fluorex 18,000 Total 318,000 Table 11-3. Users of HF Production of Fluorocarbons 70 %
Nuclear Industry 4%
Alkylation Processes 5%
Steel Pickling 5%
Other Markets 16 %
50
Table 11-4. Probability of Spills Associated with Shipments to Four Oil Refiners in Los Angeles Area Mean Probability per Year of Spill x 103 With HF With H SO4 2
Alkylation Alkylation Plant A 2.5 310 Plant B 4.9 310 Plant C 16.0 780 Plant D 9.8 490 The probabilities in the case of HF are smaller than the probability of an earthquake causing large releases at the PGDP. The probabilities of spills when H SO is used are comparable to the probabilities of releases at the PGDP, but 2
4 the consequences are likely to be less severe. The size and the rate of releases were not specified in Ref. 30, and therefore, direct comparisons of consequences cannot be made. However, the fact that the transportation accidents occur in areas with high population densities, and the only types of accidents included in the statistics are those that released the total inventory of the truck or train car, implies that many people will potentially be exposed to the toxic cloud. Therefore, the risk of injury to the public is likely, but it is not possible to make a direct comparison to the PGDP calculations.
The transportation accidents associated with large quantities of H SO and 2
4 chlorine, identified in Table 11-1, and based on accident rates in Ref. 30, are likely to lead to higher probabilities of public exposure.
j 1
t 51
12.
Conclusi* ns o
1 There is an approximately 10-3/yr chance of people off-site being injured by j
UF releases resulting from earthquake damage of the PGDP. The number of 6
1 people injured may approach 100. The analysis indicates that no fatalities are J
likely, either on-site or off-site. However, the analysis is not detailed enough to assure this conclusion with regard to those on-site. Based on the approximate models used, the average risk to workers is low, but without more detailed evaluations it is not possible to accurately quantify their risk.
If a severe earthquake were to occur, some on-site fatalities are likely because of the concentration of people. The analysis does not indicate this result because it does not model the high concentrations of toxic materials near the point of release, nor is there any consideration given to " normal" earthquake hazards, such as falling debris.
The seismic upgrade buildings C-331 and C-335 will reduce the risk of injuries to the public by about a factor of two, which is not a significant reduction given the already small risk to the public. The importance of the upgrades to worker safety is unclear because of the modeling approximations. It will be larger than a factor of two, but exactly how much larger is impossible to say.
Although there is no basis for direct comparisons of the PGDP seismic risk to the risks associated with shipping hazardous chemicals, the information obtained from a cursory search of the literature indicates that the risks may be i
similar. Transportation accident releases may not have the potential of being as large as those predicted for the PGDP, but they can occur with comparable probabilities and in areas with high population densities. There is no reason to perceive the seismic risk to the public at the PGDP to be unacceptably high compared to other industrial risks.
52
i i
References 2
1.
LLNL Letter Report, Neil W. Brown to Richard Dierlam, " Gaseous Diffusion Plant Safety Analysis Report Upgrade (SARU) Program Documentation Assessment," February 29,1996.
2.
KY/EM-174, " Safety Analysis Report, Paducah Gaseous Diffusion Plant,"
Paducah, Kentucky, Lockheed Martin, September 1996.
3.
K/GDP/SAR-118, "Paducah Gaseous Diffusion Plant Summary Rcport on the Geometrically Non-linear Transient Analysis of Process Buildings C-333 and C-331," January 1996.
j l
4.
K/GDP/SAR-105, " Natural Phenomena Hazards Evaluation of Equipment and Piping Systems in Paducah Gaseous Diffusion Plant I
Process Buildings C-331, C-333, C-335, C-337," February 1996.
5.
K/GDP/SAR-86," Analysis Summary Report for the Natural Phenomena Hazard Analysis of Process Tie Line Structures at the i
Paducah Gaseous Diffusion Plant," January 1995.
6.
K/GDP/SAR/SUB-19, " Final Report for the Inspection and Evaluation of the Process Gas Expansion Joints at the Paducah Gaseous Diffusion Plant," February 1996.
7.
- DAC-19045-CCA-58, "GDP SAR Equipment Analysis," January 12,1995.
8.
KY-734, " Final Safety Analysis Report for the Paducah Gaseous Diffusion Plant," March 1985.
9.
DOE Letter Report, Dale Jackson to Ms. Elizabeth Q. Ten Eyck, " Revised Justification for Continued Operation for the Paducah Gaseous Diffusion Plant During Seismic Modifications," July 26,1996.
- 10. K/GDP/SAR-127, " Cumulative Seismic Effects for Paducah Gaseous Diffusion Plant "00" Buildings C-331 and C-335 Piping and Equipment,"
September 1996.
- 11. " Crystal Ball Version 3.0" User Manual, Decisioneering, Denver Colorado,1993.
- 12. KGDP/SAR/SUB-1/R1, " Seismic Hazard Evaluation for the Paducah Gaseous Diffusion Plant," Paducah, Kentucky, Risk Engineering, Inc.,
January,1993.
53
- 13. " Guidelines for Use of Probabilistic Seismic Hazard Curves at Department of Energy Sites," DOE-STD-1024-92, December 1992.
- 14. Bernreuter, D.L., et al., " Seismic Hazard Chaw terization of 69 Nuclear Plant Sites East of the Rocky Mountains," Lawrence Livermore National Laboratory, NUREG/CR-5250, Vols.1-7,1989.
- 15. Electric Power Research Institute (EPRI), "Probabilistic Seismic Hazard Evaluation at Nuclear Power Plants Sites in the Central and Eastern United States: Resolution of the Charleston Earthquake Issue,"
NP-6395-D, April,1989.
16.
U.S. Geological Survey, " Review of Earthquake Hazard Assessments of Plant Sites at Paducah, Kentucky, and Portsmouth, Ohio," Interagency Report to the Department of Energy,1992.
- 17. Sykora, David W. and Davis, Jennifer J., " Site-specific Earthquake 3
Response Analysis for Paducah Gaseous Diffusion Plant, Paducah, Kentucky," U.S. Army Corps of Engineers, Waterways Experiment Station, Misc. paper GL-93-14, August 1993.
- 18. DAC-19045-CCA11, "Walkdown PKG for PDGP Bldg C-333,"
Gilbert / Commonwealth, Inc., June 1993.
- 19. " Natural Phenomena Hazard Walkdown Evaluation Summary (Draft),"
Paducah Gaseous Diffusion Plant, EQE and LLNL, May 1992.
- 20. K/GDP/SAR/SUB-10, February 1996.
- 21. Kennedy, R. P. and M. K. Ravindra, " Seismic Fragilities for Nuclear Power Plant Risk Studies," Nuclear Engineering and Design, Vol. 79, No.
1, May 1984.
- 22. Sewell, R. T., et al., " Selection of Review Method and Ground-Motion Input for Assessing Nuclear Power Plant Resistance to Potential Severe Seismic Accidents," Proceedings of the Third Symposium on Current Issues Related to Nuclear Power Plant Structures, Equipment and Piping, North Ca olina State University, Raleigh, NC, December 1990.
- 23. Briggs, G. A.1975, " Plume Rise Predictions," Lectures on Air Pollution and Environmental Impact Analyses, D. A. Haugen (ed.), American Meteorological Society, Boston, Massachusetts.
- 24. Hanna, S. R., and J. C. Chang, "HGSYSTEM/UF6 Model Enhancements for Plume Rise and Dispersion Around Buildings, Lift-off of Buoyant Plumes, and Robustness of Numerical Solver," K-25 Report No.
K/SUB/93-XJ947/2, Oak Ridge, Tennessee,1996.
54
- 25. ICRP (International Commission on Radiological Protection) 1994,
" Human Respiratory Tract Model for Radiation Protection," ICRP Publication 66, Elsevier Science Ltd., Oxford, England.
- 26. Sharp, R. D., " Calculations Based on Meteorological Data from Paducah Gaseous Diffusion Plant," Computational Physics and Engineering Division, Oak Ridge National Laboratory,1995.
- 27. Fischer, D. R., et al., " Uranium Hexafluoride Public Risk," Letter Report PNL -10065, Pacific Northwest Laboratory, Richland Washington, August 1994.
- 28. Lines, I. G., "A Review of the Manufacture, Uses, Incidents and Hazard Models for Hydrogen Fluoride," HSE Contract Research Report No.
79/1995,1995.
- 29. McGuire, S. A., " Chemical Toxicity of Uranium Hexafluoride Compared to Acute Effects of Radiation," NUREG 1391,1991.
- 30. C&EN, April 10,1995, " Production of Top 50 Chemicals Increased Substantially in 1994," April 10,1995.
- 31. Kirk-Othmer, " Encyclopedia of Chemical Technology," 4th Ed., Vol. II, 1994.
- 32. Medhekar, Subodh R. et al., " Frequency Estimates for Transport-Related Hydrofluoric and Sulfuric Acid Release Scenarios," Process Safety Progress, Vol.12, No. 3, July 1993.
55
Appendix A: Processing of Meteorology Data
)
i The 1991 and 1992 hourly PGDP meteorology data were processed in an Excel 5.0 spreadsheet to generate a joint probability density function of the wind speed, stability, and direction, for use in the Crystal Ball Monte Carlo model.
The hourly data was reviewed and all hours that did not have data for both i
the 10m and 60m elevation were removed from the record. About 91%
(15,894 data points out of 17,544) of the original data were left following this censoring. The data were then converted from F and mph to C and m/s.
1 1
The temperature data were then used to determine the Pasquill stability categories using the methods in ANSI /ANS-2.5-1984. The speed was rounded to one of the following; 0,2,4,7,10, or 13 m/s, and the wind direction was placed in one of the sixteen directional sectors used for the population i
distribution.
The processed data was entered into the Crystal Ball program, which sampled f
the data. The stability was sampled first, then the speed given the stability, t
and then the direction given the speed and stability. The joint probability function generated by a 10,000-sample run using this method was compared to the actual data and determined to accurately replicate the meteorology statistics.
56 j
l t
Appendix B: Calculated Values of X/Q l
Table B-1. Source 1 Dispersion Factors Downwind distance = 0.5 mile (805 m)
Uranium X/Q (s/m3)
Stability Class u = 1 m/s u = 2 nvs u = 3 m/s u = 7 m/s u = 10 m/s A
5.12E47 6.50E-07 5.86E 07 B
2.38E-06 2.14E 06 1.57EG 1.12EG C
6.48E46 605E46 4.30E-06 3.02E46 2.31E46 0
9 69E-06 1.35E45 9.73EG 7.165 06 5.60E 06 E
7.64EG 924EG 7.52E46 5.95E-06 F
5.09E46 5.05E-06 5.06E46 Downwind distance = 1 mile (1610 m)
Uran:um X/Q (s/m3)
Stabihty Class u = 1 m/s u = 2 nys u = 3 m/s u = 7 nvs u = 10 nvs A
1.32E-07 1.92E-07 1.89E47 B
7.51E47 6.99E47 5.56E47 4.19E47 C
2.49E-06 2.30E-06 1.74E46 1.25E41
- 9. 31E47 D
5.06E46 6.14E-06 4.74E 06 3.64EG 2 9CE46 E
3.83E46 4 47E.06 3.91E46 3.24E46 F
2.92E46 2.72E 06 2.81E46 Downwind distance = 2 miles (3220 m)
Uranium X/Q (s/m3)
Stabikty Class u = 1 m/s u = 2 nys u = 3 m/s u = 7 m/s u = 10 nvs A
2.60E 08 4.04E48 4.33E-08 8
1.48E 07 1.46E 07 129E47 1.06E47 C
5.85E47 5.64E-07 4 72E-07 3.69E47 3.01E47 D
1.67E-06 1.89E46 1.62E46 12eE-06 1.05E46 E
1.31E-06 1.50E-06 1.43E-06 128E-06 F
1.45E 06 1.05E46 1.13E-06 Downwind distance = 5 miles (8050 m)
Uranium X/Q (s/m3)
Stability Class u = 1 nys u = 2 nys u = 3 nys u = 7 m/s u = 10 m/s A
4.68E-09 526E49 5.82E 09 i
B 1.45E 08 1.50E 08 1.51E48 1.39E-08 C
6 40E-08 6.74E48 6.56E-08 5.82E 08 5.12E-08 D
2.59E47 2.88E47 2.79E 07 2.49E47 221E47 E
3.39E 07 2.50E47 2.60E 07 2.61E-07 l
F 3.80E47 321E 07 2.58E47 Downwind distance = 10 miles (16,100 m)
Uranium X/O (s/m3)
Stabihty Class u = 1 nys u = 2 nys u = 3 nys u = 7 avs u = 10 nys A
1.54E-09 126E-09 1.31E-09 B
3.36E 09 2.59E-09 2.79E 09 2.75E 09 C
1.51E-08 1.30E-08 1.39E48 1.35E-08 126E 08 0
8.12E-08 6.09E48 6.31E-08 6.12E48 5.77E-08 E
9 43E-08 8.18E 08 6.38E-08 6.86E 08 F
1.09E47 1.10E47 9.65E48 i
6 57
Table B-2. Source 2 Dispersion Factors Downwind distance = 0.5 mile (805 m)
Urannum X/O (s/m3)
Stabihty Class u = 1 nvs u = 2 nys u = 3 nys u = 7 nvs u = to m/s A
3.45E47 5.07E47 5.22E47 B
1.97EG 2.08E-06 1.59E46 1.12EG C
3.30EG 5.66E46 4.30E46 2.96E46 2.28E46 0
1.61EM 9.94E46 9.88E46 6.76E 06 5.31E46 E
2.69EG 7.11E46 7.65E46 5.77E46 F
2.25EG 524E46 4 82E-06 Downwind distance = 1 mile (1610 m)
Uranium X/Q (sim3)
Stabihty Class u = 1 nys u ' 2 nvs u = 3 m/s u = 7 nvs u = 10 nvs A
7.69E-08 1.42E-07 1.65E 07 8
6.97E47 6.95E 07 5.63E47 420E47 C
1.85E@
225E46 1.76E46 126EG 9 81E 07 D
120E-06 5.13E 06 4 81E46 3.47E46 2.82E46 i
E 1.98E 06 3.76E 06 3.94E 06 3.17E46 l
F 1.56E46 2.74E46 2.70E.06 l
Downwind distance = 2 miles (3220 m)
Uranium X/Q (s/m3)
Stability C: ass u = 1 nys u = 2 nys u = 3 nys u = 7 nvs u = 10 nvs A
1.48E48 2.96E 08 3.77E-08 B
1.45E4'T 1.46E 07 129E-07 1.06E-07 C
5 32E 07 5.64E-07 4,76E-07 3.71E47 3.02E 07 D
829E 07 1.73E-06 1.63EG 129E46 1.06E 06 i
E 9.35E 07 1.36E46 1.44E46 1.26E46 F
9.82E-07 1.04E 06 1.09E46 Downwind distance = 5 miles (8050 m)
Uranium X/Q (s/m3)
Stability Class u = 1 nvs u = 2 nys u = 3 nvs u = 7 m/s u = to nys I
A 3.49E49 427E 09 527E 09 8
1.44E 08 1.48E-08 1.49E-08 1.38E 08 C
6.29E48 6.67E48 6.50E-08 5.79E48 5.11E-08 D
2.03E-07 2.80E-07 2.80E 07 2.50E-07 222E 07 E
2.95E47 2.39E-07 2.60E47 2.54E-07 F
3.13E47 3.15E-07 2.34E 07 Downwind distance = 10 miles (16.100 m)
Uranium X/O (s/m3)
Stability Class u = 1 nys u = 2 nys u = 3 m/s u = 7 m/s u = 10 nys A
1.38E-09 1.13E-09 124E49 B
3.30E49 2.51E-09 2.74E-09 2.72E 09 C
1.46E48 1.25E 08 1.36E-08 1.33E 08 125E48 0
723E-08 6.00E48 6.33E-08 6.12E 08 5.77E-08 E
8.74E48 7.80E-08 6.07E48 6.66E-08 F
9 60E-08 1.02E-07 8.91E-08 58
l Table B-3. Source 3 Dispersion Factors l
Downwind distance = 0.5 mile (805 m)
Uranium X/Q ts/m3)
Stability Class u = 1 nys u = 2 m/s u = 3 m/s u = 7 nvs u = to m/s A
2.97E46 7.35E G 1EEG l
B 5.27EG 4.30E46 3.05Em 2.10E46 C
1.51E45 1.18E45 7.93EG 529E46 3.96E46 D
3.42E45 2.68E45 1.82E45 122E45 9.18E46 l
E 2.48E45 226E45 1.8CE-05 1.34E45 l
F 1.46E45 1.68E-05 1.70E45 i
Downwind distance = 1 mile (1610 m)
Uranium X/Q (s/m3)
Stability Class u = 1 nvs u = 2 nvs u = 3 mis u = 7 nvs u = 10 me A
6.80E47 5.78E47 4.40E47 B
125E M 1.11E46 8.7CE47 6 41E-07 C
424EG 3.61E 06 2.67E-06 1.89E46 146E46 D
1.17E-05 1.01E45 7.53E46 5.38EM 4.18EG E
9.47EG 9.19E46 7.88E 06 6.30E46 F
6 75EG 6.98EG 6.91EE Downwind distance = 2 miles (3220 m)
Uranium X/Q ts/m3)
Stability Class u = 1 nvs u = 2 nys u = 3 m/s u = 7 nys u = 10 nvs A
1.11E47 1.00E47 8.33E48 8
2.01E6 1.93E47 1.69E-07 i.36E47 C
7.95EW 7.50E47 6.23E-07 4.83E47 392E47 D
2.77EG 2.64E46 223E-06 1.75EG 1.43E-06 E
2.53E-06 2.61E46 2.47E46 2.16E46 F
3.21EG 2.45EG 2.49E46 Downwind distance = 5 miles (8050 m)
Uranium XiQ (s/m3)
Stability Class u = 1 nys u = 2 m/s u = 3 m/s u = 7 m/s u = 10 nys A
124E G 9.82E49 8.95E49 B
1.76E48 1.79E48 1.76E48 1.59E-08 C
7.66E48 7.93E48 7.52E48 6.58E-08 5.76E48 D
3.40E-07 3.55E47 3.43E-07 306E 07 2.71E47 E
5.21E47 3.74E47 3.89E-07 3.79E47 F
7.16E47 5.89E47 4.38E47 Downwind distance = 10 miles (16,100 m)
Uranium X/Q (s/m3)
Stability Class u = 1 m/s u = 2 nys u = 3 m/s u = 7 m/s u = 10 nys A
2.69E49 1.84E49 1.70E 09 8
422E49 3.11E-09 3.22E49 3.12E49 C
1.97E48 1.61E48 1.64E48 1.55E48 1.44E-08 D
9.75E-08 7.18E 08 7.44E 08 7.19E48 6.77E48 E
1.36E-07 1.12E47 8.37E48 8.65E48 F
1.93E47 1.81E-07 1.44E-07 I
l I
59
d-i j.
Table B-4. Source 4 Dispersion Factors Downwind distance = 0.5 mile (805) i Urannum X/Q (s/m3) i Stabdity Class u = 1 nys u = 2 m/s u = 3 m/s -
u = 7 m/s u = 10 nvs A
2.01E47 2.28E47 2.35E47 B
6.94E48 5.13EW 1.14E 06 1.05E 06 I-C 2.05EG 2.17E 07 1.34E-06 2.36EG 2.13E 06 D
7.78E 09 4.17E 08 7.75E47 2.84EG 4.09E 06 E-1.07E 07 5.48E47 9.71EW 2.31E 06 F
8.97E 08 4.49E-07 6.44E-07 3
g Downwind distance = 1 mile (1610 m)'
Uranium X/Q (s/m3)
Stabdity Class u = 1 m/s u = 2 m/s u = 3 mis u = 7 nvs u = 10 rrvs A
4.79E-08 492E 08 5.93E-08 B
1.14E47 3.78E 37 4.97EW 4.13E-07 C
3.44E-08 3.35E47 -
1.06E-06 1.17E-06 9.77E 07 D
6.69E 09 4.96E-08 626E W 2.10E-06 2.39E 06 E
1.16E-07 469E 07 8.20E-07 1.72EG F
8.42E-08 3.69E 07 5.58E47 Downwind distance = 2 miles (3220 m)
Uranium XeQ (s/m3)
Stability Class u = 1 nys u = 2 m/s u = 3 m/s u = 7 m/s u = 10 nvs A
9.49E-09 988E49 1.31E-08 B
7.81E 08 122E-07 1.2SE&
1.05E-07 C
6.01E48 -
2.61E-07 4.05E 07 3.67E 3.05E 07 D
5.90E-09 6.39E48 4.75E-07 1.00E.06 9.93E47 E
1.17E-07 2.84E47 5.71E 07 8.75E-07 F
8.71E-08 2.35E-07 3.90E-07 Downwind distance = 5 miles (8050 m)
Uranium X/Q (s/m3)
Stability Class u = 1 m/s u = 2 rn/s u = 3 nys u = 7 rn/s u = 10 nys A
2.94E 09 2.47E-09 2.89E 09 B
129E48 1.42E-08 1.43E-08
' 1.33E-08 C
3.41E 08 5.59E-08 6.14E4B 5.59E-08 4.98E48 D
5.74E 5.46E-08 1.81E 07 2 29E-07 2.18E-07 E
9.28E 08 1.03E-07 1.76E-07 2.16E47 F
6.44E-08 1.06E47 -
1.38E 07 Downwind distance = 10 miles (16,100 m)
Uranium X/Q (s/m3)
Stability Class u = 1 nys u = 2 rn/s u = 3 nvs u = 7 m/s u = 10 rn/s A
1.30E 09 8.99E 9.46E 10 B
3.19E49 2.38E-09 2.51E 09 2.53E 09 C
1.19E43 1.11E-08 1.20E-08 121E48 1.16E48 D
713E 09 2.55E48 5.16E 08 -
5.88E 06 5.72E 08 E
4.46E48 4.94E.08 4.77E-08 5.57E-08 F
3.23E48 4.92E 08 5.93E-08 l
i I
l i.
i I
Table B-5. Source 5 Dispersion Factors Downwind distance = 0.5 mile (805)
Uranium X/Q ts/m3)
Stabdity Class u = 1 nys u = 2 rrvs u = 3 nvs u = 7 mis u = 10 nvs A
1.50E 07 2.09E 07 2.05E47 B
1.66E48 1.92E-07 6.98E 07 9.09E-07 C
6.76E-09 5.43E-08 5.36E-07 1.35E-06 1.71E 06 D
3.92E49 1.31E-08 2.95EW.
1.15E 06 1.69E46 l
l E
3.86E48 1.52E47 5.68E.07 9.95E47 F
2.25E-08 1.55E47 4 61E&
Downwind distance = 1 mile (1610 m)
Uranium X/Q (s/m3)
Stabihty Ctass u = 1 nvs u = 2 nvs u = 3 rrvs u = 7 m/s u = 10 nys A
4.39E 08 4.79E 08 4.94E 08 8
3.46E 08 2.24E47 4 00EW 3.91E-07 C
8.94E 09 1.04EG 5.66E47 9.10E47 8.97E-07 D
3.05E49 1.41E-08 2.32EW 8.69E-07 1.46E 06 E
' 4.16E-08 1.58E-07 4.86E-07 8.45E 07 F
2.29E48 1.31E47 '
3.92E 07 Downwind distance = 2 miles (3220 m)
Uranium X/Q (sim3)
Stabdity Class u = 1 nys u = 2 nys u = 3 nvs u = 7 m/s u = 10 nys A
928E-09 9.78E49 1.08E 08 B
4.48E48 1.03E 07 1.17E-07 1.04E47 C
1.68E-08 1.38E47 3.12E-07 3.38E-07 2.99E 07 D
2.20E 09 1.69E 08 1.93E-07 5.55E 07 7.88E47 E
4.95E48 1.47E-07 2.98E47 4.67E-07 F
2.70E-08 1.01E47 2.65E 07 Downwind distance = 5 miles (8050 m)
- Uranium X/Q (s/m3)
Stability Class u = 1 nys u = 2 m/s u = 3 nvs u = 7 nvs u = 10 nys A
2.92E-09 2.46E-09 2.67E49 B
1.16E 08 1.38E-08 1.42E-08 1.32E48 C
1.97E 08 4.70E-08 5.80E-08 5.48E-08 4.93E 08 D
1.59E-09 1.91E-08
- 1.06E-07 1.86E-07 2.01E 07 E
5.51E 08 7.08E-08 1.14E-07 1.67E-07 F
2.66E48 6.55E-08 8.38E 08 Downwind distance = 10 miles (16,100 m)
Urantum X/O (s/m3)
Stabildy Class u = 1 nys u = 2 m/s u = 3 nvs u = 7 m/s u = 10 nys A
1.30E49 -
8.98E-10 9.19E-10 B
3.10E 09 2.36E 09 2.49E-09 2.49E-09 C
9.80E 09 1.0$E 08 1.17E 08 1.18E-08 1.14E 08 D
2.07E 09 1.30E48 3.89E 08 5.33E 08 5.50E-08 E
. 3.21E 3.88E-08 3.77E 08 4.86E-08 F
1.78E 08 3.38E-08 421E 08 l
61
__ _. _. _ _ _ _ _ _ _. _ _ _ _. _. _ _ _ _ _. ~. _... _. _. _ _ _ _... _ _ _. _.
)
I 4
)
i Table B-6. Source 6 Dispersion Factors e
Dowmwind distance = 0.5 mile (806 m)
Uramum X/Q (sim3)
Stability Class u=1nvs u = 2 nvs u = 3 nvs u = 7 nvs u = 10 nvs 1
A 3.04E4 12tE47 1.59E47 B
~ 6.56E-10 5.72E-09
_ 9.18E4 144E47 i
C 124E-10 2.31E 09 2.10EG 2.22E47 100E W D
4.48E 10 1.30E49 8.39E49 2.45E47 5.72E47 E
9.27E49 1.65E48 174E48 175E47
{
F 429E49 122E 08 866E48 4
Downwmd distance = 1 mile (1610 m)
)
Uranium X/O (sem3)
Stabshly Class u = 1 nys u = 2 nvs u = 3 nvs u = 7 nvs u = 10 nvt 1
A 156EG 4.03E48 4.03E48 I
B 1.53E43 2.07E48 1.43E47 2.53E-07 C
&77E 10 5.34E49 5.34E48 2.82E47 425EW-j D
6.61E-10 2.16E49 1.00E48 1.51EW 3.72E-07 E
9.12E-09 1.80E48 4.87E-08 157E47 F
3.59E49 8.18E49 4.59E48 4
Downwind distance = 2 miles (3220 m)
Uranium X/Q ts/m3) j.
Stability C! ass u = 1 nvs u = 2 nys u = 3 nvs u = 7 avs u = to nvs 3
A 7.99E49 9.36E49 909E49
)
8 3.69E-09 3.48E-08
&38E G 9.11E 08 l
C 8.96E-10 1.04E48 8.92E4 1.96E47 2.21E47 l
i; D
4.09E 10 1.62E 09 1.10EG 1.01E 07 229E 07 i'
E 9.39E49 222E 08 166E G 1.71E47 I,b F
3.92E49 723E 09 3.31E48 Downwind distance = 5 miles (8050 m) j Uranium X/Q (s/ma)
Stability Class u = 1 avs u = 2 nvs u = 3 m/s u = 7 nws u = 10 nys l
A 2.79E49 143E49 2.50E49 8
151E49 1.12E 08 1.34E48 128E 08 C
1.76E49 1.61E 08 4.14E-08 4.84E 08 4.61E 08 0
1.88E-10 1.16E-09 129E 08 6.42E 4 1.07E47 e
j E
1.31E48 101E48 4.33E48 7.74E-08 F
4.23E 09 9.13E-09 2.30E48 Downwind distance = 10 miles (16,100 m)
Uranium X/Q (stm3)
Stability Class u = 1 nvs u = 2 nys u = 3 nvs u = 7 mts u = 10 m/s A
1.27E 09 8.93E-10 8.9BE 10
)
B 2.55E49 224E49 2.44E49 2.42E 09 C
2.98E49 722E-09 1.05EG 1.10E 08 1.07E 08 D
1.54E-10 1.01E49 1.03EG 100E 08 4.01E 06 E
1.11E 08 1.68E48 102E4 3.09E 08
{
F 153E 09 7.94E49 1.60E48 i
e i
4 1
e e
62 i
-