ML20244D315
| ML20244D315 | |
| Person / Time | |
|---|---|
| Site: | Peach Bottom  |
| Issue date: | 04/14/1989 |
| From: | Zech L NRC COMMISSION (OCM) |
| To: | Sarbanes P SENATE |
| Shared Package | |
| ML20244D317 | List: |
| References | |
| NUDOCS 8904210281 | |
| Download: ML20244D315 (83) | |
Text
_ ._ _
l Distribution , {
.T+
VStello
.BBoger )
7 = [g n, o' UNITED STATES :
JTaylor DMossburg
{
! N NUCLEAR REGULATORY COMMISSION HThompson JBlhha'
'RMartin JLinville j
.5 I
WASHINGTON. D. C. 20566 EDO 4371- DCrutchfield 1
I EBeckjord,RES'
[ April 14,1989 TMurley JSniezek Local PDR CHAIRMAN bYar98- PDI-2 Reading
.0GC WButler BClayton SECY'
'The Honorable Paul S. Sarbanes M0'Brien .MMiller FMiraglia' FGillespie.
-United States Senate Washington, D.C. 20510 WRussell, RI,lJScinto NRC PDR
Dear Senator.Sarbanes:
JPartlow
'I am responding to your letter of March 22, 1989, in which you and Senator Mikulski requested that the Commission reserve judgment-on'the restart of the Peach Bottom. Atomic Power Station until issue! aised by Maryland residents have been addressed. The NRC
. staff. 2s reviewed the concerns of Harford County Councilwomen Joann ' arrott and Barbara Risacher, the Maryland Safe Energy Coaliuon, and the Peach Bottom Alliance that you referred .to us, and their detailed comments on the issues raised are set forth in Enclosure 1.
With one exception, the issues raised during the February 28 and March 2, 1989 public meetings in Bel Air and Bethesda, Maryland, were considered earlier.in the-staff's review of Peach Bottom.
The one exception is the request for a system of radiation monitors surrounding the plant. Although such a system was not considered specifically in the context of Peach Bottom, the NRC staff previously requested a. technical contractor to conduct a generic evaluation of the potential benefits of a monitoring:
system of this type and in. April 1982 published the contractor's findings in NUREG/CR-2644, "An Assessment of Offsite, Real-Time Dose Measurement Systems for Emergency Situations." A copy of this report.is enclosed'(Enclosure 2).
NUREG/CR-2644 concluded that it was highly questionable whether a fixed-station emergency monitoring system could provide techni information sufficiently reliable to be of use in a decision-making process in an emergency situation. Wide-range effluent monitors,'along with the enhanced in-plant monitors required since the:Three Mile Island accident, provide much more definitive information for off-site emergency decision-making.
Consequently, the NRC staff decided not to include a requirement for such a fixed-station system in the most recent revision to Regulatory Guide 1.97, " Instrumentation for Light-Water-Cooled Nuclear Power Plants to Assess Plant and Environs Conditions During and Following An Accident."
The Commission has not yet reached a decision on the restart of Peach Bottom. However, we have scheduled a public meeting on April 17, 1989, at 2:00 p.m. at our headquarters building jn Originated: NRR:RMartin ,
' I h2gg % 7
. *f
2 Rockville, Maryland, to consider the possible restart of the plant. I can assure you that the decision we reach will take into account your concerns and those expressed by Maryland residents.
The Commission will not permit restart of the plant unless we have reasonable assurance that the public health and safety will be protected.
Sincerely, onlo ta. L h,J[.
Lando W. Z
Enclosures:
- 1. Staff response to concerns of Harford County Councilwomen, Maryland Safe Energy Coalition, and the Peach Bottom Alliance, with attachments
- 2. NUREG/CR-2644, "An Assessment of Offsite, Real-Time Dose Measurement Systems for Emergency Situations" Idertical ltr sent to: The Honorable Barbara A. Mikulski United States Senate
9 ENCLOSURE 1 The staff reviewed the concerns of Harford County Councilwomen l Joanne Parrott and Barbara Risacher, the Maryland Safe Energy Coalition, and the Peach Bottom Alliance. With the exception of radiation monitors outside the plant, these concerns have been resolved by the NRC. Our assessment of these issues has been documented in our Safety Evaluation Report of. October 19, 1988, our Integrated Assessment Team Inspection Report of March 6, 1989, and in numerous other inspection reports and correspondence.
With respect to the Mark I containment, the NRC staff concluded that operation of nuclear power plants using this containment design does not pose an undue risk to the public health and safety. The Commission is considering whether there are additional measures that may be taken by licensees that would enhance the safety of plants with Mark I containments but has not yet completed these deliberations. On the basis of the assessment of the adequacy of the Mark I containment and the lack of any connection between the Mark I containment and the issues that caused the shutdown of the Peach Bottom plant, the staff does not propose to require further action on this issue before the Commission's decision on the restart of the plant.
The licensee for Peach Bottom made available to the public and to NRC by letter dated March 1, 1989, the recent INP0 letter of February 21, 1989. A copy is attached.
Concerning the participation of the State of Maryland in restart-related activities, we note that a representative of the State, Mr. Thomas Magette, has access to the plant and customarily attends many routine and special meetings at the plant and at NRC.
Mr. Magette recently indicated in correspondence with the staff that he is in general agreement with the NRC staff's Integrated Assessment Team Inspection findings. Mr. Magette also expressed the belief that, subject to the completion of certain items, the licensee has demonstrated readiness to operate Peach Bottom in a manner that does not pose an undue risk to the citizens and the environment of Maryland. Mr. Hagette's letter of March 7, 1989, is attached.
With respect to the reporting of information by the licenree, the Peach Bottom Technical Specifications and NRC's regulations impose the requirements for reporting information to the NRC. Cop 1es of the information provided to us by the licensee can be found in the Local Public Document Room for Peach Bottom in the State Library of Pennsylvania in Harrisburg, Pennsylvania and in the Public Document Room in Washington, D.C. The NRC issues press releases and makes public announcements on events of major significance but, of course, does not have the authority to require the .
licensee to report information through the media.
u
ENCLOSURE 1 ]
i I
The staff's recent response to a representative of the Peach j Bottom Alliance (Ms. Jean Ewing, dated March 20, 1989 (attached))
on the radioactive waste disposal issue noted that this. issue received the attention of Congress in the passage of the Nuclear Waste Policy Act of 1982 and the Nuclear Waste Policy Amendments Act'of 1987. A schedule for actions by the Department of Energy i and the NRC on radioactive waste disposal has been developed, and I this issue does not require resolution before the restart of Peach Bottom.
I I
NUREG/CR-2644 I ENICO-1110 An Assessment of Offsite, Reaj-Time ;
I Dose Measurement Systems f6r l Emergency Situations Prepared by W. J. Maeck, L. G. Hoffman, B. A. Staples, J. H. Keller Exxon Nuclear idaho Co., Inc.
b Nuclear Regulatory Commission l
l i
l 9
L.
NUREG/CR-2644 ENICO-1110
)
>! j
- An Assessment of Offsite, Real-Time i Dose Measurement Systems for ,
Emergency Situations f
Manus:ript Completed: March 1982 Date r Nished: April 1982
, Preparm by
? W. J. Maeck, L. G. Hoffman, B. A. Staples, J. H. Keller Exxon Nuclear idaho Co., Inc.
P.O. Box 2800 l Idaho Falls, ID 83401 Prepared for
- I. Division of Systems Integration Office of Nuclear Reactor Regulation
! U.S. Nuclear Regulatory Commission Washington, D.C. 20556
) NRC FIN A6461 i
i I.
(
i h
p t
s.
-- - - - - - - ~ ~
3 NOTICE Availability of rieference Materials Cited in NRC Publications Most documents cited in NRC abdications will be available from one of the following sources:
- 1. The NRC Public Document Room,1717 H Street, N.W.
Washington, DC 20555
- 2. The NRC/GPO Sales Program, U.S. Nuclear Regulatory Commission, Washington, DC 20555
- 3. The National Technical Information Service, Springfield, VA 22161 Although the listing that follows represents the majority of documents cited in NRC publications, it is not intended to be exhaustive.
Referenced documents available for inspection and copying for a fee from the NRC Public Docu-ment Room include NRC correspondence and internal NRC memoranda; NRC Office of Inspection and Enforcement bulletins, circulars, information notices, inspection and investigation notices; Licensee Event Reports; vendor reports and correspondence; Commission papers; and applicant and licensee documents and correspondence.
The following documents in the NUREG series are available for purchase from the NRC/GPO Sales Program: formal NRC staff and contractor reports, NRC-sponsored conference proceedings, and NRC booklets and brochures. Also available are Regulatory Guides, NRC regulations in the Code of Federal Regulations, and Nuclear Regulatory Commission Issuances.
Documents available from the National Technical Information Service include NUREG series reports and technical reports prepared by other federal agencies and reports prepared by the Atomic Energy Commission, forerunner agency to the Nuclear Regulatory Commission.
Documents available from public and special technical libraries include all open literature items, such as books, journal and periodical articles, and transactions. Federal Register notices, federal and state legislation, and congressional reports can usually be obtained from these libraries.
Documents such as theses, dissertations, foreign reports and translations,and non NRC conference proceedings are available for purchase from the organization sponsoring the publication cited.
Single copies of NRC draft reports are available free upon written request to the Division of Tech-nical Information and Document Control, U.S. Nuclear Regulatory Commission, Washington, DC 20555.
Copies of industry codes and standards used in a substantive manner in the NRC regulatory process are maintained at the NRC Library,7920 Norfolk Avenue, Bethesda, Maryland, and are availcble there for reference use by the public. Codes and standards are usually copyrighted and may be purchased from the originating organization or, if they are American National Standards, from the 1S American Natio7 tandards Institute,1430 Broadway, New York, NY 10018.
L
ABSTRACT An evaluation is made of the effectiveness of fixed, real-time mon-itoring systems around nuclear power stations in determining the magni-tude of unmonitored releases. The effects of meteorological conditions on the accuracy with which the magnitude of unmonitored relealis is de-termined and the uncertainties inherent in defining these meterological conditions are discussed. The number and placement of fixed field de-tectors in a system is discussed, and the data processing eouipment re-Quired to convert field detector output data into release rate informa-tion is described. Cost data relative to the purchase and installation of specific systems are given, as well as the characteristics and in-formation return for a system purchased at an arbitary cost.
i J
l
-)
9
)
i iii
- .. . . . - - . . - ~ .
SUMMARY
The Nuclear Regulatory Comnission has been considering a requirement that each operating commercial nuclear power station be fitted with an offsite real-time emergency monitoring system. Currently, sev 1 power stations have installed, or are in the process of installing, mgnitoring systems of varying degrees of complexity and sophistication.
Prior to deciding whether to reauire all stations to install an offsite real-time emergency monitoring system, the NRC reauested an independent evaluation of the usefullness of such a system and an assessment of the validity of the information obtained from the system.
The information provided by this study will be used to aid the NRC in their determination of whether or not to reauire that fixed offsite l
real-time emergency monitoring systems be installed at all operating and planned commercial nuclear power stations.
f This study addresses several aspects of the offsite real-time emer-gency monitoring system concept. The primary iten.: receiving attention in this study are:
- 1. The ability of a fixed real-time monitoring system to detect and cuantify monitored and unmonitored releases.
- 2. The ability of the system to detect and cuantify an unmonitored release in the presence of a known release.
i
- 3. An assessment of the uncertainties associated with estimating the magnitude of an unmonitored release.
4 The number of stations reovired to detect a release and the uncertainty assotiated with the detected value.
- 5. The availability, cost, and the instrumentation requirements for a system.
l i
r An augmented effort of the study was to determine the characteris-tics and information return that might 'be obtained from a close-in (0.5 mile) syrtem with capital costs limited to $500,030.
A matrix approach was used in this evtluation in which the three major parameters were,1) the measurement range of the detector;32 ) the accuracy of the final results, and 3) the costs. l, The general conclusions from this study are presented below. The uncertainty estimates are based on the use of simple error analyses of the meteorological expressions reovired to describe plume shapes and atmospheric transport.
- 1. While a ring of detectors around a nuclear power station can provide the means for monitoring releases; the number of sta-tions reouired for two detectort to provide information within a factor of 5 of each other can be as large as 50 or more for one installation.
- 2. The use of short-time (15 min) data from a fixed offsite moni-toring system to project downwind dose rates is a complex and highly uncertain process. Based on our study the uncertainty associated with a projected value is at least a factor of 10 or l more.
- 3. The use of a fixed offsite monitoring system to determine the I
magnitude of an unmonitored release in the presence of a moni- -
tored release is highly questionable. Depending on the ratio of the unmonitored release to the monitored release, uncertain-ties of factors of 25 and 50 are common.
- 4. Several vendors of monitoring eouipment were contacted relative to cost and performance characteristics of the available in-strumentation. In addition, we contacted several power stations and state agencies involved in the installation of fixed real-time environmental monitoring systems. While the cost factors vi !
\ - _ _ _ _ _ _ _ _ _ _ _ _ _ _ _
l' for the instrumentation were relatively fixed, the installation l
costs were highly variable. Based on this study the cost per monitoring station ranges from 525,000 to 165,000. Depending l upon the specific site characteristics the cost for a 32 station system could easily exceed 51,000,000 while only providing data with uncertainties in the reage of factors of 10 to 50.7 l.
- 5. The placement of a simple limited (1500,000) detector system in proximity (0.5 mi) to a reactor may not provide reliable in-formation in the case of an emergency for several reasons. Of prime importance is the limited number of stations (8-16) that ,
could be installed and the consequence that a plume might go undetected. A second serious problem, especially in the case of a BWR, is the building shine factor which could give a sufficiently high background signal to negate detection of the
, plume radiation.
In general, it is highly Questionable that a fixed station (16-32 units) emergency monitoring system can provide sufficiently reliable technical information to be of use in a decision-making process in the event of an emergency situation.
This conclusion should not preclude consideration of the installa-tion of such a system. A monitoring system could be used to develop site specific meterological information and could develop improved public relations with the populace. It should be emphasized, however, that the stations should be judiciously placed so as not to convey false information, vii
t *
. TABLE OF CONTENTS
,t ABSTRACT . . ... . . . . . . . ... . . . . . . . . . . . . . iii
SUMMARY
. .. . . . . . . . . . . . . . . . . . . . . . .. . . y 1.0 ' INTRODUCTION . . . . . . . . . . . . . . ... . ... . . . . . I 1.1 Background . . . . . ................. 1 1.2 Objective . . . . . . . . . . . . . . . . . . . . . '1I 1 1.3 EvaluationCriteria.................[ 2 2.0 QUANTIFICATION AND ASSESSMENT OF-THE UNCERTAINTIES
. ASSOCIATED WITH THE MEASUREMENT OF AN UNMONITORED RELEASE .......................... 5 o
2.1 Prediction of Downwind Atmospheric Concentration Values . . - . . . . ................. 6 2.2 Prediction of Downwind Atmospheric Dose' Values .... 15 2.3 Uncertainties Associated with the Quantification of an Unmonitored Release .............. 21 3.0 DETECTOR PLACEMENT AND REQUIREMENTS ............ 25 3.1 Detector Placement and Response Functions . . . ... . 25 l 3.2 Building Shine and Background' ............ '
30 4.0 INSTRUMENTATION REQUIREMENTS, AVAILABILITY AND SYSTEM COSTS ........................... 34 4.1 Instrument Description and Requirements ....... .
34 4.2 Instrument Availability . . . . . . . . . . . . . . . . 38 4.3 System Costs . . . . ................. 40 5.0 MATRIX EVALUATION . . . . ................. 48 6.0 MINIMUM COST EMERGENCY SYSTEM . . . . . . . . . . . . . . . 52
7.0 REFERENCES
. . . . . . . . . . . . . . . . . . . . . . . . . 56 APPENDIX A. BRIEF
SUMMARY
OF EXPERIMENTAL RESULTS TO COMPARE MEASURED AND PREDICTED GROUND LEVEL CONCENTRATION VALUES I'
A.1 85Kr Experiment at Savannah River Plant ...... A-1 A.2 ORNL Assessment of Hanford Experiment ........ A-1 A.3 Excerpts from a Workshop on the Evaluation of Models used for Environmental Assessment of Radionuclides Releases . . . . . . ................. A-3 ix
_ _ _ _ _ _ _ - _ _ _ _ _ _ _ _ _ . . _ __ ___-mm______-.-___-.-.-_-._.____._m________a___-___.____.________m._ _ _ . _ _ _ __ _ . _ _ _ _ . _ _ _ _ _ _ _ _ _ - . _ - - - - _ __-__ _ __ -
.. ~
. A.4 Results of a Survey of Programs for Radiological Dose Computations - ..................... A-5 APPENDIX B. VALUES FOR oy AND or USED IN CALCULATION FIGURES 7
- 1. Matrix Parameters ....................f.. 4
- 2. Model to Evaluate the Estimate of an Unmonitored Release in the Presence of a Known Release ........ .... 6
- 3. Comparison of Short-Term Diffusion Factors (Stability Class A)
Depicted for 6 Different Diffusion Parameter Systems . . . . . 13
- 4. Comparison of Short-Term Diffusion Factors (Stability Class D)
Depicted for 6 Different Diffusion Parameter Systems . . . . . 13
- 5. Comparison of Short-Term Diffusion Factors (Stability Class F)
Depicted for 6 Different Diffusion Parameter Systems . . . . . 14
- 6. Projected Center Line Dose as a Function of Stability Class and Distance For a Ground Level Release ........... 19
- 7. Effect of Release Height on Dose Rate as a Function of Distan'e for Stability Class B, D, and F. .......... 20
- 8. Uncertainty in Calculated Values of an Unmonitored Release in the Presence of a Monitored Release ............ 23
- 9. Plume Shape Analysis for Determining Detector Requirements ........................ 26
- 10. Number of Detectors Reauired at 1600 m to give Response within 200, 300, and 500% .................. 27
- 11. Detector Requirements as a Function of Cloud Dose Gamma Ray Energy .................... 28
- 12. Effect of Building Shine on Detector System Response .... 32
- 13. Schematic of Offsite Monitoring System Basic Components . . . 35 14 Matrix Parameters .....,................ 51 l-A-1 Measured to Predicted 85Kr concentrations ......... A-2 A-2 Comparison of Different Dose Calculation Models, Class F .. A-6 l l
A-3 Comparison of Different Dose Calculation Models, Class C .. A-7 j i
X
\
y .
-I. Errors in X (Ground-Level Average Concentration) for a One Unit Assignment Error in Stability Class . . ... 9 II. Errors in X (Ground-Level Average Concentration) for a One Unit Assignment Error in Stability Class . . ... 10 III. Variability in Stability Class Assignment Based on Two Different Measurement Methods . . . . . . . . .. 11 IV. Range of Uncertainties Which can be Associated with l, an Unmonitored Release Having a True Value Of 1 . . . . ... 24 V. Detector Requirements ................... 29 VI. Vendor Data for Real-Time Monitoring Systems . . . . . ... 43 VII. Climatronics Meteorological Accessory Package . . . . . . . . 46 VIII. Installed Real-Time Monitoring System .. . . . . . . ... 47 A-1. Evaluation of Handford Experiment by ORNL . . . . . . . . . . A-4 B-I.- Values for oy and oz Used in Dose Calculations . . . . . . . B-1 1
1 Xi f l
4
1.0 INTRODUCTION
1.1 Background
It has been reconrnended that systems of offsite, real-time envi-ronmental monitors be installed around nuclear power statils. The ,
premiseisthatthedataobtainedfromsuchasystemcould,whh1 coupled with meteorological data, provide information relative to unmonitored, as well as monitored radioactive effluent releases, and provide the basis for inaking downwind dose rate projections during an emergency accident situation.
1.2 Objective The purpose of this study is to evaluate this proposal and to pro-vide information to aid the NRC in determining whether or not to rectire that a fixed offsite monitoring system be installed at all nuclear power I stations.
The primary items considered in this study are:
- 1) The ability and related accuracy of a fixed real-time monitoring system to detect monitored and unmonitored releases.
- 2) The ability of a fixed real-time monitoring system and ass 9ci-ated calculational methods to detect and quantify the magnitude of an unmonitored release in the presense of a known release.
- 3) To provide an esti, nato of the credibility (uncertainty) of the information associated with the estimated value of an unmoni-tored release.
- 4) To determine, using calculations 1 methods, the number of fixed stations required to detect a release and to provide an estimate of the uncertainty in the ineasured dose ar, a function of the i
number of stations.
m:-- -_
5)
To provide cost data relative to the installation, operation, .
and maintenance of a fixed real-time monitoring system.
- 6) To determine the charat.teristics and information return for an 800 m (0.5 mile) (probably onsite) emergency sysf5n with f.
capital cost limited to $500,000.
1.3 Evaluation Criteria The variables to be considered in this evaluation are ;'sted below and shown in a matrix array in Figure 1.
- a. (0.1 4 background) to 10 R/hr Range of Detector (Assume
- b. (1.0 x background) to 10 R/hr Backgroundof10pR/hr)
- c. (10xbackground)to10R/hr
- d. (100 x background) to 10 R/hr Accuracy of Dose to: a. i factor of 2
- b. factor of 5
- c. factor of 10
- d. factor of 50
- e. i factor of 250 Order of Magnitude Costs a. $ 250,000 for Installed System (ExcleJ- b. $ 750,000
- c. $2,000,000 ing Costs for Detectors)
The following assumptions are used throughout the evaluation:
- 1. The detectors will be available as "off the shelf" items ar.d will have the sensitivity to make the required measurements.
Calibration procedures will be available to assure a detector
[ response accurate to i 25%.
I 1
i
14
- 2. The monitoring stations will be located within 3200 m (2 miles) of the ' plant and the measurements will be averaged on a 15-minute time scale. The costs of the detectors will not be considered; but costs for signal averaging, transmission, and correction for background will be included.
7 i
- 3. Meteorological information requirements will be those rgguired to satisfy NUREG-0654 Regulatory Guide 1.97 and the Proposed Revision to the Regulatory Guide 1.23.
4 Computerized analysis of the dectector and meteorological input will use in-house or "off the shelf" hardware and software to provide accurate and intelligible output for use in control room decisions. For offsite, real-time monitoring system output to be intelligible, the information presented to the operator in the control room must describe in real time the significant features of the release, such as dose distribution and contours In addi-within two miles and characterization of the source.
tion, the computer analysis must provide for downwind dose pre-diction capability beyond two miles.
- 5. The source term to be evaluated will be limited to mixtures of radionuclides which are nondepciiting, i.e., only the noble gases without radioactive daughter s.
3-
._ - -_____:_ _ _ - _ _ _ _ _ _ _ _ _ _ _ _ _ - _ - _ - _ e _ _____ :__-___-_--___-__-___-_-
i l j l ll i j
y
/I /l o m.
/ /7/ s r
e ic
/ .
/// 0 5
2 X
s
/// -
r t
e 0 e 5 m X r o a r
t a
/// 0 y 1
X ar F
c a
c u
P i
t M
x r
a
/// A c
c .
~//
1 5 e r
X u
g i
- F 2
X r~/~
4 h
/
R r
h
/
R r
M R
r h
/
R p
r p p y 0 1 0 0 0 0 1 0 1 1
1 a-
+
I l I l
2.0 QUANTIFICATION AND ASSESSMENT
0F THE UNCERTAINTIES ASSOCIATED WITH THE MEASUREMENT OF AN UNMONITORED RELEASE {
j To provide an evaluation of the accuracy which might be obtained from a fixed offsite real-time monitoring system we used simple statis- ;
tical methods of error analysis. Of particular concern was the quality and credibility of the values obtained for an ynmonitored releas in the '
presence of a known release.
The model used for this evaluation is shown in Figure 2, in which D is dose related to background, B
Ry is the known or monitored release, R is the u_nknown release, 2
Dy is the dose related to Ry, D2 is the dose related to R2 ' ""d D is the total dose measured by the receptor.
T Thus, the total dose, DT , is the sum of Dy , D2 and DB which are in some form proportional to Ry and R2 '
(1)
DT=D1+D2+DB where Dy=Ry and D2=R2 To obtain a value for the unmonitored release in the presence of a known release, the following procedure is used. First, the measured value for R y is converted to a dose, D y, using the equations given in Section 2.1. Second, the calculated value Dy is subtracted from the measured value DT to give a value for D2. Third, the value 02 is then converted to a value for R ,2 using the same equations to obtain It is assumed that DB is small in comparison to D g and D 2 D. y and can therefore be ignored.
The following is a discussion of the errors associated with each step in the calculational procedure and an assessment of the uncertainty in the value of R2 ' l
D; 4
o i.
Rg 0"
2 R
0 W
DT ICPP-S 7991 Figure 2.
Model to Evaluate the Estimate of an Unmonitored Release in the Presence of a Known Release 2.1 Prediction of Downwind Atmospheric Concentration Values The first calculational step involved in the model given in Figure 2 is conversion of the measured release R g to a dose Dg . The most commonly used method for calculating the exposure to a receptor involves converting the known release value to an atmospheric concentration value -
at some downwind distance and then integrating the concentration over !
the volume of the plume. The exposure is then proportional to the pro-duct of the integrated concentration and the decay energy of the radio-nuclides present in the plume, expressed as an exposure rate per unit release (R/hr)/(C1/s) at 1 m/s wind speed. The detector response cal- ,
culated in this study is in exposure rate. However, in the remainder of this report the authors eouate exposure rate and " dose rate" as is com- i mon practice. ,
l
i i
The atmospheric concentration value at some downwind distance is usually calculated using the Gaussian plume ecuation. This is an empiri-r cal diffusion formula which assumes constant wind speed, no wind shear, and flat topography. The eauation for a continuous point source release is:
7 l.
OG(z),_ exp ( (2)
X(x,y,z) = (y/oy)2) 2noyo zM where:
x= atmospheric concentration at 'a calculated point (x,y,z) for 3
a release point h meters above the ground, C1/m Q= source term (release rate), C1/ seconds G(z) = exp -4((z-h)/oz ) + exp -h((z + h)/o,)2 cy = horizontal atmospheric diffusion parameter, m o, = vertical atmospheric diffusion parameter, m 3= average wind speed, m/sec y = cross wind distance, m h = release height, m x.y,z = coordinates of the point where the concentration is calculated In this relationship the most critical terms are the values for o and o,. Both of these terms carry a different value for each y
class of atmospheric stability and downwind distance. Unfortunately, the values for oy and og are not explicitly mathematically defined and as such must be determined empirically. A number of different field experiments have been conducted to determine o, and a, as func-tions of atmospheric stability conditions (weather class) and downwind distances.
-7 l
l l
J TL-L-_ A
o p< ..-
Currently, the most widely used data sets for o y and o, 'are those based on -the Pasauill-Girford model- for atmospheric dif fusion. .
Several methods have been used to establish' the atmospheric stability.
class which must be determined prior to obtaining the values for e y
and o,.' One -general classifying. scheme is based on isolation. - cloud cover, and wind speed. The standard deviation of the horizEtal wind direction is also used to establish the stability class. Anothdrmethod,
( recommended by the NRC2'(Reg. Guide 1.23) uses the temperature gradient between 10 and 60 m (or the release height) above the. ground to determine the stability classification. None of these methods are without uncer-I-
tainties, and in many cases the selection of the proper . atmospheric stability class may be in error by one or more classes.
Assuming an error of one stability class in the assignment process (i.e. - assigning class D for a real class E conditions), we determined the error which would be introduced in the value. for x based on the 3 for adjacent atmospheric stability classes.
Pasquill-Gifford curves The effect on the value for x at distances of 1000 m and 3000 m for release heights of 10 m and 100 m is given in Tables I and II, respec-tively. For a near ground-level release, the error in the predicted groundlevel average concentration could range from a factor of 2 to 10 ,
for a one unit misassignment of the stability class. For a 100 m release the errors can be much larger.
To establish the freauency with which the stability class may be in i question, four months of meteorological data for an inland nuclear power station were evaluated. For this station, both the standard deviation of the horizontal wind directinn and the temperature gradient data were available on an hourly basis. An analysis of these data indicates that the assigned stability class based on these two methods differed by one class 43% of the time, and by two classes, up to 25% of the time.
The results shown in Table III indicate that the stability class assign- l ment based on the two methods differed about 60% of the time. Thus, the downwind ground-concentration value could be in. error by a factor of 5 about half of the time just from this source.
. g l n e i v t s e c ul -
i d l d e e n r 0 d u o o J -
p 1 4 4 2 2
- m rg r e &
me d m e 0n u h l
0U p t 0
3 n s
=
a t i c Dt s i
) c s d N i u e O d a r G p I
TS e 0 2 2 -
t v TL r r o NC o e ,
E t v CY O 0 NT c m OI a s F i 0 CL
- I r 0 EB o s 0 GA r s a 3 AT r RS E l
ct a E m VN t d
AI 0 c e LR 1 i d n D g
EO t e i s VR h r 2 2 s s ER g p 5 3 3 LE i - s a l a
- e r c DT NN H me d e .
UE e 0n h r 4 OM s 0U t o RN a 0 d f f GG e 1 n o (I
X S l
e =t a se r S R c C u o A Di l t N d s a c I T e 2 2 i v a I r 5 3 3 f SN p RU - s s n O
RE r
e a o a i y
RN v l s EO O c u b f
yf n
.A t i i
o i
1R l d t O i a l
eF b d r b a r t a t o n T d s ff e c
e e i n n s gs u G o ia B A C B D C E D F E r - c t l sl sC l e ei g A h u a t q r s e f a v I P a e
l p
s m es a u
rl a A B B C C D D E E F x E
TC h
I' i'
j l
t i
c d
e r
p 0 3 3 6 1 2 3 r
me d 0n 0U 0
3
=
) Dt N c O i I d T e 0 3 A S r 3 6 1 2 3 R S p TA s -
NL r r E C o e C t v N Y c O OTI a C F L
A IN 0 t L
0 c 1 i E R d V O ,
e 0 E R t r 2 5 0 L R E h p 5 1 1 1 8 g -
D i r N T e me U N H d OE 0n RM e 0U G N s 0 (G I a 1 e
X SS l e =t c
NA R Di I d T 0 SI e 2 5 0 r 5 1 1 1 8 R N p O U -
R r R E e E N O v O
.A I
I R O
l eF b
a T d e
ns gs ia B A C B D C E D F E sl sC A
s es u a A B B C C D D E E F rl TC
',.o' p l
Table III.- VARIABILITY IN STABILITY CLASS ASSIGNMENT
-BASED ON TWO DIFFERENT MEASUREMENT METHODS
'Date No.' Observation One Class Difference .Two Class Difference June-1974 640"' 274 (43%)b 39 (6%)
' July-1974 .430 186 (43%)- 113 6%)
Aug.-1974 613 262-(43%) 76 (r2%).
Sept.-1974 661 ~ 281 (43%)1 152-(23%)
L 'a) Number - of L hourly observations .for which both wind variability and t'emperature differential data were available.
' b) . Percentage. of the time - that the stability class assignments were.
- different.
At this point it might be well to recognize that the Gaussian' plume eauation only provides concentration estimates and not oose estimates.
In general, the uncertainties in the dose values are not as variable as the ground-level concentration values, because the cloud gamma' dose is an integrated value as opposed to a point concentration value. This fact, however, should not preclude consideration of the uncertainties in concentration values predicted by .the Gaussian plume eauation because the ground-level concentration values are more important with respect to the beta dose factor, the inhalation dose factor, and the ground-level concentration value for radiciodine, which may be the dominant factor in an accident case. The uncertainties associated only with the dose values will be treated in detail later in this Section.
Another item which must be considered regarding the uncertainties associated with the- Gaussian plume eauation and ground-level concentra-tion values, is the validity of the primary diffusion data based on the Pasauill scheme. The basic Pasouill diffusion data were derived from tracer experiments which involved a ground-level release over very flat terrain with sampling periods of a few minutes at distances of up to about 1 km. Unfortunately through time and widespread usage, the
- - - ~ ' ~
a- . . . .. . - . . . . . - - - -
r.: ' original naturG of the experiment sGems to have been forgotten by many users of'the data. and the original results have been extrapolated to
' -include' elevated release points (up to 100 m) and to distances of up to 100 km.
Pasquill diffusion parameters are primarily applicable to short
'f' term releases at or. near ground-level over relatively short distances (1 km) and cuite flat terrain.
7 Because of the restrictive nature of the Pasouill scheme; i more re-j cent experiments have been conducted to attempt to better cuantify the diffusion parameters for the more realistic ' cases (i.e. hills, rough terrain, forests, metropolitan areas, and elevated releases). Some ex-:
amples are given in References 4, 5 and 6. Vogt7 .and Brenk 8
. ad have reviewed these experiments in . some detail and compared the diffusion parameters derived from these experiments to each other and to Pasouill.
In.some cases the downwind concentration values may differ by factors of.
10 to 1000, depending upon the stability class involved.
Figures 3, 4 and 5 taken from Brenk 8
give comparisons . of the short-term diffusion factors for the various experimental results' for stability classes A, D, and F as a function of distance, for a release height of 100 m.
agreement.
For class A, unstable diffusion, the data are in good However, with increasing atmospheric stability, significant differences are evident (Figures 4, 5). For class D stability at a dis-tance of 1000 m, the difference between the Pasouill diffusion factor and the majority of the other systems is a factor of 10 to 15. At 3000 m the difference is about a factor of 5.
i For class F stability there is' little agreement in the diffusion factors for the various systems and differences of a factor of 100 to 1000 are common.
These data are presented not to dwell on the large differences be-tween the various systems, but rather to emphasize the need for selecting I the most applicable system for - a given site.
Ideally, the preferred situation is to develop site specific data. Unfortunately, experiments of this type are difficult and oxpensive to conduct. Brief descriptions a - _ _ - _ _ _ __ __-__ _ - - - _ - - _ - _ - _ _ _ _ _ _ _ _ _ _ - . _ _ _ - _ _ . _ _ _ _ _ . _ _ _ _ _ _ _ . _ _ . _ _ _ _ _ _ _ _ . _ _ _ -
)
10-4 Diffusion Category D 5
Release Height 100 m 2- ,p . /.g *m. x gn.5
//
j
/ 'l ,/ .
A g 10 5 !/ /
' / A
/ % ('s'%
j/
I /
/ / /
5 -
j j j 12 5 gn.T
.l I 1
,i ,
l f
l .
I 1
f i !
l5 0 i !
i
/ I Brookhaven j '
S 2 - .! [ f ------ St. Louis
/ 1 / - -- - Pasquill
' $ 10 s ! ;
l I f - ~~ Klug
)
/ . --~~ Julich 50 .f 5-
'/ j i j
--~~ Julich 100 2- I I j I 10 8 5 5 in3 5 5 10 4 in2 icw.s.m.
Source Distance (m)
Figure 3. Comparison of Short-Term Diffusion Factors (Stability Class A) f Depicted for 6 Different Diffusion Parameter Systems (From Brenk, ref. 8) 10 Diffusion Category A l 5
2 .. -p Release Height 100 m
- h. 5 . // / A
- u. .3 '/ /./,I Qx
. m
! "5; l
'f// // !/
xh 'N
-Brookhaven-N'\, N h
- 2 f/ I .f
> !//
St. Louis
- - - -Pasquill g
Il 10*8 !
g! l !
- ----Klug N'N 5 ,1 l
._..__.Julich 50 \s ;
f#
Julich 100 l 2 Il 10'I
' 4 l 10 2 2 5 10 3 2 5 10
' Source Distance (m) ,,,,,,,,
Figure 4. Comparison of Short Term Diffusion Factors (Stability Class D)
Depicted for 6 Different Diffusion Parameter Systems (From Bronk, ref. 8)
--~~=_=-=_:____-_==-_--- ________3--- __ _
4
,J o
- N- .-
/
f
/jI S3 l- ll
- /
' - f, - s F m // -
y 0
/--/
_ r 0 -
o 1 .
g j t
_ e h ., -
t a g _ , /
/j i
C e - ,
i n
o s
H e
s a
/ /I j j 2
)
m f
f i
u l e
e _
// /
/
(
e c
D R f n l/ /.
/
3 t oi s a
/ l,/ j
- f l:f l/
j/
3 D e
c r
u
/, o S
/, s n
e 0 /
v s 00 ai l 51 f
//
l h ui koL ouqgcc hh o sul ii l
/
rt.al uu /
BSPKJJ i 1
- f
/ I I
2 i
I 1 g I
2 4 5 2 5 5
2 6 5
27 s 2 8 s 2
o 3
- - - - - ~
0 0 0 0 0 0 1 1 1 1 1 1
^? E $oE c2 j 5 $ pa or#
h
and the result and data obtained from some recent experimental programs are given in Appendix A. Included are reviews of the Savannah River 85 Kr experiment,9 the ORNI. assessment of the Hanford experiment 10 ,
excerpts from a Workshop on the Evaluation of Models Used for the En-vironmental Assessment of Radionuclides Releases.II and results of a survey of programs used for radiological dose computations.12 Presently, it is virtually impossible to give a definitive esticate of the overall uncertainty to be associated with the prediction of down-wind concentration values, especially for data related to short time pe-riods. However, based on our study and those of others 9,10,11,12 we believe that a predicted value which may vary by a factor of 10 to 25 from the true downwind concentration is not unreasonable. Even this estimate may be low if site specific diffusion parameters are not available.
2.2 Prediction of Downwind Atmospheric Dose Values The calculation of the cloud gamma exposure from a plume is a two-step process. First, the radionuclides concentration of the plume is calculated using the Gaussian plume dispersion ecuation given in Section 2.1 (Ea. 2). Second, the total cloud gamma exposure rate at the detec-tor is calculated by using a point source approximat1 ion and integrating over the source distribution (i.e. the volume of the plume). Both com-ponents of the exposure rate calculation have been incorporated into a code developed by Science Application, Inc. 13 which was used in this study to establish detector response values.
The assumptions and paramerers used to calculate the cloud garrna values presented in this report are given below.
- 1. The Gaussian plume eauation given in Section 2.1 (Ea. 2) was i used to establish the plume dispersion and downwind concentra-tion values. The values used for o y and o g are given in Appendix-II.
l 1
t i
. .- 2. The cloud gama exposure rate' at a receptor was obtained by l r
using a point source approximation and integrating over the l volume of-the plume. This involved an extensive numerical sum- -
mation of small volume elements. Although this is a lengthy process,; we believe the results are more representative than f
those obtained from the use of infinite or semi-infginite cloud i
} approximations. The following is the methodology uded to cal-l-
culate the cloud gamma exposure rate to a receptor.
q exposure rate D (h) = C pa- EB(pR) T (3) where C = 6.87 x 10-5
= mass absorption coefficient for air at energy E (m2/g)
E = energy per ,s.oton MeV/ photon B(pR) = buildup factor T = photon flux (photons) m2-s photon flux T (photons) , s esir (4) m2-s 4nr2 where s =photonemissionrate(photons /s) r =distar.cefromsource(m) p =totallinearattenuationcoefficientforair(m-1)
The photon emission rate, s, was determined by assuming a small volume, dV, at concentration X as follows:
S (photons /s) = 3.7 x 10 10 XI gdV (5) i 7
where l 3.7 x 1010= the the number of disintegrations per second per curie X= radionuclides concentration in the small volume element 3
dV(C'/m)
Ig= no:nber of photons of energy E per disintegration 3
dV=volumeelementconsidered(m)
Combining equations 4 and 5 x 106 b()=25 E Ig Xe-F B(tar) dV (C')
Equation 6 is the contribution to the exposure rate at the detector due to the small volume element dV. The total exposure rate was obtained by integration over the volume of the plume. When using the code, Xp/Q was used in equation 6 instead of X to subsequently give results in terms of b iT/Q or exposure rate per unit _ release rate (R/h)/(Ci/s) at 1 meter per second wind speed.
l 1
l l
l - . - -
},-
l-L Several calculations were made to evaluate the dose rate to a recep-l tor as a function of stability class, distance, and release height.- The
- dose rate as a' function of' distance for several stability classes for a-
-ground level _ release is shown'in~ Figure 6. At a distance of 3200 m (2 miles), the centerline dose can vary by at least four orders magnitude over the extreme stability class range of A to F. The uncapainty in the doso as a function of adjacent stability. classes can also be esti-mated from Figure 6. For example, at a distance of two miles the dif-ference in the maximum centerline dose between stability class B and C is approximately 8, Land between stability class C and D, approximately
- 3. These values are. for .an average gamma ray energy of #80 kev (133Xe). ' The differences are only slightly less for an' average energy of 250 kev.
{ The effect of the release height on the dose rate as a function of distance for three different ~ stability classes is shown in Figure 7.
I For the worst case, class F, the dose rate at short distances (500-1000-m) can vary l a factor of 6-12 between a release height of 0 to 100 m.
-This difference decreases as a function of distance. At 3200 m the dif-ference is approximately 2.5.
In the discussions presented up to this point, we have assumed that the centerline of the plume has passed -directly over the receptor, thereby giving the maximum dose value. The probability of this happening is auite remote. The number of detectors and their placement reauired to give accurate dose readings will be discussed in detail in Section 3.
k Based on the calculated data given in Figures 6 and 7 and the pro-blems presented with respect to an accurate assessment of the prevailing weather class and to a knowledge of the location of the source term, it is our opinion that the calculated downwind dose value must carry an associated uncertainty of at least a factor of 10 or more.
i w
F.
2 -. -
Cg 9% F C
B l
. h F B
10
\B C p*D
- A B 'C A
8 1 10-4--
JE
~
E, .
- e.g A
Stability Class 10-57 A l Case: h=o i l
' ' ' J -
10 - --: -- -
1000 2000 3000 0 500 ""
O! stance (m)
Figure 6. Projected Center Line Dose as a Function of Stability Class and Distance For a Ground Level Release
.____- - -_ _ _ _ - - - _ - - - - _:_ :~~ __TI~_~~_ _____-___-_______-______-_---__-___A
4 i
100 i , ,
'T l.
l 10.0 -
E E ii ,8-X I ii I
o Class - F 5
cc x o Class - D O
I z
5 1.0 -
i Class - B C
l >
0.1 -
1000 2000 3000 j Distance (m) 'CPP S 7912 j i
Figure 7. Effect of Release Height on Dose Rate as a Function of l
Distance for Stability Class B, D, and F 1 i
i l
3
w- - -- -- - _ _ _ _ _ - _
2.3 Uncertainties Associated with the Quantification of an Unmonitored' Release The uncertainties and range of values associated with quantifying the magnitude of an unmonitored release (R2) in the presence of a known 1
release (Ry ) were calculated based on the model given in Figure and
-the relationship, DT"01+D2 where D i a R1,'and D2*R' 2
'The calculation of the expected error in R2 assumed the following conditions:
- 1. 1 R(constant) 2 1 1 Ry (variable) 10 1 0.1
- 2. The unceri.ainties assigned to 01 were:
i factor of 2 (200%)
factor of 5 (500%)
i factor of 10 (1000%)
factor of 25 (2500%) .
I
- 3. . The same uncertainties were assigned to D2 ; however, in many cases the uncertainty associated with D2 may be larger than D because the height of the release is probably unknown.
1 1
- 4. No significant errar was assumed in the measured dose, DT ' j
- 5. The background contribution is small. If the background is significant with respect to the measured DT value the resul-tant error will increase.
- 2.1 -
- - - - . . - - - = - ---=_r- -
The results of.the error analysis are given graphically in Figure 8 and listed in Table IV. In Figure 8, the range in the values for R 2 as a function of the ratio R g/R2 are given for a family.of uncertainty assignments for Dg and D. From this simple error analysis' it is 2
concluded that uncertainties of factors of 10 to 25 are possible for the calculated value for the'unmonitored release, especially whe9 the magni-tude of the unmonitored release is eaual to or smaller thd) the known release. For the case where the unmonitored release is large with re-spect to the known release the uncertainty in the unmonitored release will approach the error associated with the values for D1 and 02*
For example, in the case where the known release and the unmonitored release, R g and . R 2
respectively, are of equal magnitude (in~this l case,1) and the assumed uncertainty in the calculated values for Dg and D is a factor of 10, the value for R 2 can have a range of 0 to 2
19 for a true value of 1. For the case where the ur: monitored release is 10 times larger than the known release and the uncertainty in 0g and D is a factor of 10, the value of R 2
can have a range of 0 to 11 2
for a true value of 1. For the case where R 2 is only one-tenth of R
y the uncertainty in the value 1 for R 2 increases dramatically, having a range of 0 to 100 for an uncertainty of a factor of 10 in 03 and D '
2 This error analysis only presents the range of relative values to be associated with an unmonitored release having an assigned value of
- 1. It does not provide an estimate of the true value of the unmonitored value. The accuracy of the true value for the. unmonitored release de-pends on the location' of the plume relative to the detector. If the ;
plume centerline is several degrees removed from the detector, the mea- 1 i
sured value for D T could be low by a factor of 2 to 10 depending on j the proximity of'the plume to the detector. This effect is discussed in l detail in Section 3.
i l 1
[ -
i
w s :.
e
{
{
10.0 x
. o=2 '"T o=5 0 10 _f
~
o - 25 I
I
)
1.0 -'
~
I I a
\
e 2 2 - '
2 2 .
I e v -
E 2 o o
= =c -
c o o E
E c ~
E Am 1
True Value of R2 cc o 0.1 -i>x0 0
- - )
m -
\
sc . \
1 1
i Ja I
i
' i ' ' '
' ' ~ ' ' LL 0 - 10 2D 30 40 50 60 70 80 90 100 120 l icer s.roo, Possible Value For Unmonitored Release, R2 Figure 8. Uncertainty in Calculated Values of an Unmonitored Release in the Presence of a Monitored Release :
l
-o-Table IV RANGE OF UNCERTAINTIES.WHICH CAN BE ASSOCIATED WITH AN UNM0NITORED RELEASE HAVING A TRUE VALUE = 1.
UNCERTAINTY RANGE IN CALCULATED
. CASE: 1 D,D2 1 VALUE OF 2 Rg = 10 200% 12 to -4.5
=
j R 2
1 500% 45 to -7.8 RT = 11 1000% 100 to -8.9 2500% 265 to -9.6 CASE: 2 Rt=1 200% 3 to O R2=1 .500% 9 to -0.6 RT =.2 1000% 19 to -0.8 2500% 49 to -0.9 CASE: 3 Rg = 0.1 200% 2.1 to 0.5 l 500% 5.4 to 0.1 R2=1 1000% 10,9 to 0.01 RT = 1.1 2500% 27.4 to -0.1 I
e
. 3.0 DETECTOR PLACEMENT AND REQUIREMENTS 3.1 Detector Placement and Response Functions The response functions and requirements for a ring of detectors were determined by calculating the dose rate from a plume TI various distances from the plume centerline. Figure 9 gives the dosel rates at 1600 m for three different stability classes (A, C, and F) as a function of distance from the plume centerline for a ground level release of 1 C1/s. The curves given in Figure 9 describe one-half of the plume shape; from the centerline to one edge. The plume shapes and dose rates were calculated for 80 kev gamma rays (133 Xe) using the equation and input factors given in Section 2.2.
The number of detectors reautred for two adjacent detectors to give responses within factors of 2, 3, 5, and 10 of each other was determined based on the plume shape (i.e., the width of the plume). For the plume.
shape corresponding to stability class C (Fig. 9), the lateral distance from the plume centerline which gives a signal eaual to one-half of the maximum was determined to be M.8 degrees. Dividing a 360 degree circle by this value gives a value of 46, which is the number of detec-tors reauired for two adjacent detectors to give a response within a factor of two of each other. The same process was used to establish the number of detectors reouired to give readings within factors of 3, 5, and 10 of each other for each stability class. In all cases, it was assumed that the plume centerline was directly over one detector. This is the worst case situation.
Figure 10 shows the number of detectors at 1600 m reauired to give responses agreeing within 200%, 300%, and 500% as a function of stability class. These results are for straight line meterology, a release height of 100 m, and an average gamma ray energy of 80 kev. For class F weather (the worst case) about 85 detectors are recsuired for two adjacent detec-tors to give signals within a factor of two of each other. For a ground-level release, approximately 100 detectors would be required for a factor l of two agreement. Even for class B weather and a release height of l 100 m, about 36 detectors would be required for agreement within a factor of two. ,
t
__,__-_.-___.______--~_________m._ --_a_m_-- _._ M
l 10-2 3
4 1
- Key:
1/3 (
)
h
- F 1/2 (105)
Fraction of fNumber of Maximum Value Detectors h Class F 10-3 ~
~
Case:
Class C 1/2 (46) l
~
c1/3 (36) h=0m x *
~ , 1/5 (30)
E 0
[ 10-4--- 1/10 (24) e :
E -
E -
F
% C
~
Class x 1/2 (24) 10-5.-
A 10-6-- '
O 2 4 6 5 10 12 14 16 18 20 22 24 Degrees From Centerline scena.no Figure 9.
Plame Shape Ar.alysis for Determining Detector Requirements
{
~
_ . _ _ _ . _ _ _ _ _ _ . _ _ . . _ _ _ . . _ . _ _ _ _ _ _ a
e C
100 , , , , , y
/
Distance: 1600 m (1 mile) 200 %
90 -
Release Ht: 100 m f#/, -
/
X
O m /
200%
f
/ 1 Energy: 80 kev 80 -
/ .
/
/
/
l \
70 -
/ -
/
/
[
/%
O 300%
2 60 -
/ -
o / ,
Iie /
/ I e /
O /
/
g 50 -
O g 500%
.o x z 40 O Agreement
,/ Between 2 ~
/ Detectors
/
2 30 -
0 -
X 20 - -
O 10 - -
1 0
A B C D E F Stability Class 'C"" 8 7'"
Figure 10. Number of Detectors Required at 1600 m to give Response within 200,300, and 500%
10-2 ,
-x % x 1500 K x 1/2(40)
_ x 'T u 1/5(25) 250 kev 10-3 -- 1/2(42) 80 kev 1/2 (44 1/5 (27)
_ x\ 1500 kev o 1/5 (30 e 10 O :
E -
EE. _
_ Case: 250 kev Distance - 1600m Release HT. - 100m 10-5._ Stability Class - C Key:
j- 1/5 ( )
N Number of -
Detectors Fraction of 80 kev l
Maximum Value 10-6 8 8 ' ' ' ' ' ' ' ' ' '
2 4 6 8 10 12 14 16 18 20 22 24 " " " ' "
Degrees From Centerline i l
Figure 11. Detector Requirements as a Function of Cloud Dose Gamma Ray Energy l
l
Table V. DETECTOR REQUIREMENTS l
WEATHER CLASS A B C D E F DISTANCE, RELEASE AGREEMENT BETWEEN m HEIGHT, m TWO DETECTORS NUMBER OF DET dTORS x2 23 30 40 68 69 90 0 x5 15 19 25 36 42 51 800 x 10 -- 16 20 28 33 38 x2 25 30 39 43 46 58 x5 16 19 24 26 29 30 800 100 x 10 -- 16 19 21 23 24 x2 24 32 42 65 -- 100 1600 0 x2 23 34 45 62 72 86 x3 18 28 36 49 57 64 1600 100 x5 15 23 30 40 46 50 x2 -- 44 55 69 103 138 x5 -- 34 40 46 65 80 3200 0 x 10 -- 32 36 40 55 66 l
I
Table V gives additional data for distances ranging from 800 m to 3200 m.
As expected, the number of required stations increases with distance.
These data also show the dependence on release height, with the worst case being a ground level release.
The effect of more energetic gamma rays from shorter-175/ed noble gasnuclidesonthenumberofdetectorrequirementshasbeenI. valuated.
Plume shape and detector requirement calculations similar to those shown ;
in Figure 9, page 26, were made for three different gamma ray energies:
80 kev, 250 kev, and 1500 kev. The conditions assumed were class C weather '
stability, and a release height of 100m. The results given in Figure 11 show little change in the overall plume shape with respect to gamma ray energy and hence, little significant difference in the number of l detectors required to give responses within factors of two or five of each other.
Based on the results of these calculations, it is quite evident that offsite real-time monitoring systems consisting of 16 or even 32 units may not provide information on centerline dose values and plume
)
location because of the limited number of detectors. In some cases, especially for exi.remely narrow plumes (stability classes E and F), the plume might pass between two detectors and go undetected, or if detected, the magnitude of the dose associated with the plume could be greatly {
underestimated unless it passed directly over one of the sparsely placed detectors. Conversely, in our opinion, the installation of a 100 unit l
detector system is not practical, feasible or cost effective. l
{
3.2 Building Shine and Background Some consideration has been given to the installation of real-time l monitoring systems within the confines of the site boundary; distances of 500-800 m are typical. In the event of an accident, it is quite pro-bable that the background resulting from building shine could result in a significant signal to near-by detectors. To evaluate the magnitude of ;
this component we calculated the dose to a receptor as a function of l distance for the following condition-l l
j' ; -
l is j
, 1.. 100% of the Krypton and Xenon isotop;s and 50% of the iodine isotopes were released from the core.
- 2. 1 Of these amounts 1% of each leaked to the reactor building. l l
3.
The following reactor building contents (based on WASHg00(14) for a 12 hr decay period).
.f 87 Kr 2.4 C1 131 88 4 1 1.2 x 105 Ci Kr 1 x 10 C1 132 133 1 4.8 x 103C1 Xe 4.8 x 105C1 133 1
5 1 7 x 10 C1 135 4 134 Xe 4.1 x 10 C1 I 22 Ci 135 4 1 6.5 x 10 C1 4 No significant shielding (BWR).
- 5. Building volume = 5 x 10 4 m, 3 Using the building contents given above, the dose rate from this source was calculated for various distances from the building using the code ISOSHLD-II .
The results for the rare gas and iodine compo-nents are given_ separately in Figure 12. These data indicate a signifi-
. cant' increase in the normal background level (0.01 mR/hr) due to the contents of the building, especially at distances of less than 1000 m.
The cuestion of shielding the detectors from this source has not, in our opinion been adeauately resolved. Complete shielding of the de-tector from this source would only negate the signal from a plume. The .
value of partial shielding in the direction of the building shine is Questionable considering the scattered radiation from the building.
To evaluate the impact of the building shine on a signal from a passing plume we have included in Figure 12 the contribution from a plume of 133 Xe based on the building contents given above and a leak rate of it/ day, giving a source term of 0.055 C1/s. Also assumed was class E weather, a wind speed of l' m/s, a release height of 100m, and that the bulk of the iodine was retained in the reactor building or trapped by the filter system and therefore had no significant contribution to the plume dose.
7__.
4 i
l 103 k
\
- 7
- h, 102 _ -
Noble g
_ Gases \
~
' Radiolodines
\
! 'a- \
i M
\
en
.E -
2
'5 m 1__
Release HT. - 100m *
- Stability Class - D Leak Rate - 1%/ Day of Building Inventory 10 Noble Gas Plume Dose
- X x x_
I I I I I
.0-2 ICPP S 7914 200 400 600 800 1000 Distanc a (m)
Figure 12. Effect of Building Shine on Detector Response I
l t . _ _ _ _ _ _ _ _- - _ _ _ _ _ _ _ _ _ _ _ _ _ _
' The r:sults of this calculation ' clearly show tha signif.5cance of For the accident the building shine f actor relative to the plume dose.
case where significant cuantities of the volatile radioactive products are in the reactor building, little or'no information regarding the plume dose could be obtained from detectors located close to the rea building.
7
$. )
1 i
3
4.0 INSTRUMENTATION REQUIREMENTS, AVAILABILITY AND SYSTEM COSTS J
The basic components of an offsite real-time monitioring system are shown in Figure 13. Al'so identified, are the major cost areas to be considered in establishing an offsite, real-time monitorin] system.
Currently, virtually all of the existing real-time monitorinh systems 5
which have been installed are for the purpose of monitoring routine re-leases rather than for use in emergency situations. Although the imme-l diate use is different, the eauipment and costs should be similar. Be-l cause many of these systems have only recently been installed or are in the installation stage, little information or cost figures are available in the open literature.
To obtain the information necessary to establish an estimate of the costs involved in the installation of a system for use in an emergency situation, several utility stations and state agencies were contacted.
These conversations ranged from rather open discussions to ouite gu3rded comments, and in some cases, a reluctance to ouote cost values. Also vendors of potentially useful instrumentation were contacted.
A review of the instrumentation ro;uirements and availability of real-time monitoring systems is given in Section 4.1. Section 4.2 gives a review of total system cost and an estimate of the installation costs based on information gathered for existing or planned systems.
4.1 Instrument Description and Requirements ~
The basic requirements for an offsite, real-time monitoring system are listed below and shown diagrammatically in Figure 13.
4.1.1 Field Stations. Field Stations will consist of radiation detecting devices and associated electronics. The stations would pre-ferrably have the capability of signal averaging and onsite readout.
The radiation detection system should be capable of measuring dose rates
- h. - - - _ - _ _ _ - _ _ _ _ _ _ _ _ . _ _ _ - . _ _ . _ _ - _ . _ _ _
v e
OFFSITE, REAL-TIME MONITORING SYSTEM MAJOR COST AREAS MAJOR COMPONENTS T
O1 Power
{
if 1f Sen rs HV + Detector + A Electrometer 4-if Field Micro Unit j Trans.
~'
> Processor lator MODEM g
=
E= a. Telemetry 3r E Data
$ b. Dedicated Transmission 5 Phone 3
\ ,
E-k c. Hardwire
\._ _ _ _ _
. \
_& \
\
5 Receiver G \G Central y Computer yControl Station Processor A f 5
v if #
Storage Printer .
ICPP.S 7888 Maintenance Calibration Operation Figure 13. Schematic of Offsite Monitoring System Basic Components i
from 1pR/hr to 10 R/hr with reasonable accuracy (+ 10%) and respond in
^
a relatively flat manner to photons of 50 to 3000 kev. The detector (s) should be weather proof and the associated electronics enclosure main-i- tained at suitable operating conditions. This may require heating or cooling depending on site conditions. For the winter of 1981-2, the heating requirement could be significant. A provision for backup power should be made. -7 l.
Additional instrumentation, such as meteorological sensors and io-dine sampling devices may be added to the field stations. This addi-tional instrumentation may provide useful data but the cost per field station will be increased.
Data Transmission. Three practical methods exie,t for 4.1.2 transmitting data from the field stations to the central processing unit and commands from the central processing unit to the field stations.
These include direct hard wire connections, dedicated telephone lines and radiotelemetry. The choice for specific site will depend on economic and environmental factors. The selected system must be capable of:
- 1. Bidirectional operation,
- 2. Error detection and correction,
- 3. A useful transmission rate, and
- 4. A transmission structure compatible with the accumulated data.
Direct wire connections often provide the most reliable connections.
However it may be impractical to use hardwire connections over water or at distances greater than one mile.
j I
i i
i I
h . . _ _ __ _
i i
,l Telephone systems using voice grade lines for data and command 1
' transmission can be installed by and then leased from telephone compa-nies. ,
Bidirectional transmission is preferred, although half-duplex is- l adeouate. (
)
I Several commercial vendors including those of real-timeTenviron-mental monitoring systems supply compatible telemetry systems l.Line of sight transmission of up to one mile can be performed i: sing an FM system.
As with other field stations electronics, transmitters and encoders must be protected from the environment and, at colder sites, heated.
4.1.3 Central Processing Unit (CPU). The CPU performs the acaui-sition, reduction and storage of data describing radiation dose rate conditions existing at each field station. . The CPU also performs the following functions:
- 1) diagnostic testing of these data to provide dose rate and meteorological condition time average values for each station, 2)' the comparison of radiation data to alarm points, 3) compi-lation of historical data files, and 4) polls the field stations for radiation dose rate levels at reauested intervals. The CPU also should have an interface for transferring the acquired data to an external computer for plume analysis, characterizations, and the ultimate predic-tion of downwind dose values. Hardware reauired for these tasks inclu l
- 1. Data receiver and decoder
- 2. Microprocessor, i
~
I
- 3. Data storage device, 4 Printer,
- 5. Command entry device, and
- 6. Back-up pover supply.
i
- - - ^ ^ ~ ~ ~ ~
(' E l
-L 7 L4.2 Instrument Availability y
1
[,L .
h, The capital costs.of obtaining-and installing an emergency monitor-~
ing' system were /stimated from costs _of existing routine monitoring sys)
-tems.
- . To prepare capital ~ cost estimates for-.an emergency . monitoring system, three vendors of' routine monitoring systems (GCA Corporation, p
-Harshaw Chemical -Company and Reuter-Stokes) were contacy.
'None 'of these vendors offer systems which are capable _ of. simultaneo{ sly monito q
l- ing routine radiation releases and meteorological conditions, transmit-ting this information to a CPU which subsequently models the release and provides dose rate charactet istics.
The existing systems' provide real 1 time. remote location dose raa data which 'is transmitted to 'a CP
' converted to. information such as count or dose rate averages, anomalies-and alarm points.
d . All three vendors offer a CPU which can be interfaced I with an external computer for characterizing and predicting dose. rates.
It is interesting to note that the only external computer that each of the three vendors reconnends interfacing to their CPU is the Digital Equipment Corporations PDP-11/34.
Details of the features, capabilities and price for each of the three systems are discussed below and summari-zed in Table XI.
GCA Corporation The GCA Corporation has installed several of their " Guardian" sys-tems at power stations in the United Kingdom for the purpose of provid-ing routine real-time environmental monitoring.. The " Guardian" system -
employes two GM detectors (low range, 10-6 -
10-2 R/hr, and high range 10'3
- 10 R/hr) at each field station for radiation detection.
In addition, a "Maypac" particulate and iodine filter system with con-stant air pump can also be placed at each field station. Data transmis-sion from the field stations to the central processing unit is usually performed by VHF radiotelemetry, but other methods are possible. The
" Guardian" CPU provides immediate hard copy and visual display of current field station readings, system diagnostics, and data logging. Although the " Guardian" system has been marketed in the USA since 1981 it has not been installed and operated at any power station in this country. In-sta11ation costs and operational characteristics of this system can be l obtained by contacting power station personnel in the U. K. I
--,, __ _ - - - - - - , - _ _ - - - _ _ _ - - - - - - --.-a- - - - - . - - - - - _ - - - - - - - - . - - . - - - - - - . - - - - - - _ - - - - - - - - - - - - _ - . - - - - _ - - - - - . - _ - - - - - - - - . - - _ _ - - - - - - - - , - -
jg
~- -
The Harshaw Chemical Company The Harshaw TASC-4 systems may be used for routine real time envi-ronmental radiation monitoring. This system uses two scintillation de-seven tectors per field station to give monitoring capabilities over decades of signal. Data transmission from the field stations to the CPU e used is by dedicated hard wire systems because generally the units inside of buildings where the distances are short. An advantage of the t
Harshaw TASC-4 system is that all field station electronics, except the of preamplifier, can be placed in the CPU thus minimizing the effects weather on the system, lowering the potential for tampering at the field Components of the stations, and centralizing much of the maintenance.
CPUs of these syetems also include counter-timers, printer, and computer interface modules. To date none of these systems have been installed to function as routine real time monitoring devices at distances being con-sidered in this study.
Reuter-Stokes The Reuter-Stokes Sentri-1011 system, designed specifically for i
real time routine radiation monitoring, has been installed at several nuclear power stations in the USA. The field stations of the Sentri 1011 systems are equipped with high range (10 10 R/hr) and low range (10-6 - 10-2 R/hr) pressurized ion chamber detectors and as-sociated instrumentation. Reuter-Stokes is presently developing a single detector to provide accurate monitoring over seven decades of signal which should result in a reduction of a capital cost and installation.
Data transmission from the field station to the CPU of the Sentri-1011 system can be accomplished by radiotelemetry, dedicated telephone lines, or hard wire. The Sentri-1011 CPU performs field station data reduc-tion, system diagnostics, and data logging. Historical information can be obtained in hard copy and the unit contains an interface port for an external computer.
'I _ .- - -_ -_ -_ - _- ___ - _ _
~
e ,
, Reuter-Stskes 1s; the only vendor which offers a compatible' metesrologi-cal accessory package for. their field stations.- This package the "3-D 6
Wind System," is marketed by C11matronics_and is described in Table VII.-
4.3 System Costs-l .y L Several commercial power reactor stations and state radi blogical, monitoring agencies were contacted relative to obtaining cost inho'rmation i'
regarding the purchase and installation of offsite, real-time monitoring i: systems. Although the systems which have or are being installed are for the purpose of monitoring' routine releases, the basic instrumentation
.and cost data should be similar for an emergency montoring system. In some cases, detailed cost information was not available because the sys-
'tems were still.being installed or existing systems were-being modified or expanded. Information regarding date of installation, number of fixed stations, distance front the source, and type of data transmission is given in. Table VIII. All of these systems are using the Reuter Stokes Sentry-1011 monitoring system.
The cost factors for these systems are auite variable because of varying degrees of' instrumentation complexity and whether a subcontractor was . involved in the design, purchase, and installation of the system.
The range in the costs per monitoring unit is approximately from $20,000 ,
to $40,000/ unit. In general, the higher priced systems included a mete-orological sensing component and/or additional subcontractor costs. For :
< purposes of this survey an average cost of about $30,000 per unit appears j reasonable. This value includes the costs of all monitoring and data transmission instrumentation. The cost of a central data processing unit and a computer for extended data handling and reducing capabilities is variable depending on whether dedicated or existing hardware is used for this purpose.
A much more ambiguous cost is that regarding the installation of l l the field units. If the monitoring unit is installed on existing sup-ports (power transmission poles) and the power source is readily avail-able, the installation costs may only amount to a few thousand dollars
($3,000 - 5,000) per unit. Conversely, if special supports are reauired k
- l. .__ __ _ _ _ _ _ _ _ _ _ _ _ _ _ - _ . _ _ ___
_q or if the units lare installed over water, the average station costs could increase five foldl($25,000/ unit). Additional cost would also be' incur-For example, red if 'special power lines and installation are required.
use of uninterrupted power from the Auxiliary Building could add several hundred'thousand dollars to the overall costs.-
Other costs which must be' considered but are difficult tMouantify .l
' include.designandengineering,purchaseofland:ifnecessary,keprecia- l tion, routine maintenance, dedicated telephone line leasing fees, and ]
operating cost. The last item could be significant-if. a group of dedi-j.-
cated operators -(meteorologists) were assigned to operate the system and
~
evaluate the data.
Based on the data currently available, the following range 'of cost figures are given'for a 16 unit station at a distance of 2 miles. i.
Range of Costs (000) 400 - 640-
- 1. Instrumentation $20-40K/ unit I
40 - 110
- 2. Data Collection and processing equip. I 80 - 400
- 3. Installation $5-25K/ unit 1
50 - 200 f 4 Design and Engineering I
(
100 - 200
- 5. Contingency
$670 - $1,610 l __
c _
The lower cost figure does not insure uniform placement of the mon-itoring units because existing support poles are considered ' for use.
'Thus, it is quite probable that a release could go undetected Considering that we if it con-sisted of a compact plume (stability class E or F).
are only referencing a 16 unit system this same Therefore, commentone could apply even if the monitoring units were uniformly spaced on a ring.
kEtire could raise a cuestion regarding the technological validityI of the ,
of stations to give highly re1Pable concept. To increase the number measurements would result in increasing the overall cost of a system by several million dollars.
cC trqn d
-. i aoea fr
- . nt t r . oo
- oa si s c r cnrn ge nr t e ioeo cr nmti i l
ea o rt pc ut ta st er t umu ia i
g n
s ii ni of e cood e
l t enl ce r
sd .
n o
cem
,e r M s) tl i aa ci eU ap nrnt Uat cP t m opra Pf oC sa i ed Crd
_ r( e tdt en P d r anxr rt a t l p t aEe on l i e s h fi r
, e S an it d
.t .
M rU f p dr osy Krt E
T t
n l c e l oa ectra 2. en 4uo t u S e l x i e a ol Y
C Ae F rdfp 5. p c S
d G e n N t o I
R a i O
r t t a T s t I
n s N o '
O m d M e l I
VE d . e M
e i f
el EI n si LT B - i o .
um i n
AL TA s e ee
, s r rn d E
R ai i i o e t m w w d .
_ R as o ue O Dn d dt l c a r r ci F r a ap nr T H Hu I p A
_ T g A n n
_, D nr e i R
oe v - d e a u O
D N
s c
iw to ap s
. e r ..
l c
i dl n ) pf n E nn eld al rno i m_ V oo fie pahe sn/ts n ir otr tt oni gR n o ac riW pc si rs0ni do i t .
t e as Sl rS o 1 at
_ E e . tf ta t c d h) s co si si l r t ur e hr . n
_ eo aEo . t srt ar ro it e(t p eehivh er Fc w cu dd/w / pt c
e 2ek aR eC t oft c ocydr0 Ke waea e wel nu5 7l D TCdb Td( at1 $e l
_ a
_ c
_ i1 m1 s e- e s hC i e CS t c A s i i wT e l r a r i P h u b
_ s . t a 1 ro a p
_ 8
_ aC e a 9 H F C 1 h'
san atl i r 1 csa v ,e 3syv sr
,et gx os e rae tnnt er pi oin i
t od nt n ut s i sa al e -
rpa ,e
. mt at osvu '
g n t mc r rne i eaea fd eid s pdtf l t mo s) y ,sr aen m eU t ye tii5 n
cP eyst aF oC l a n d d ,n r( el si nea P t pu s .odl t st r escoa li siae snem-sos n S
an adtt mo rU h su ei K
M t a p ct5 rn E n Utdm oa a 0 5
T e P ano rttl n S C Cdac P saai $
- Y S
G N
I
. R d O e
)TI e
, t .
ae n d N o
' n cl t O o ib i nM h p
di es t
a o e t C M E ,l ds o s (I n ye rp I T o rt o n V L - i t . e i s ede en E EA s mer il ri d e
L ai eti B R t m l aw w d u
A as ec e l t T OR Dn tid dn
, a d r ro cs F r F ea ah no T Rdh Hp I c A
T . %
A d n r 0 D e n e hh n2 e
gd a - v t/e R l ne o e ire +g wpw
. h hn O s aar et e s nC t to D c t re t ug 0t si0 i ih N i di wdaAn n )1 eit0 w wp E nn egronl a al r b a6 e V oo fiopau paht V r+ n nl ir odt c .r sn/aeee o oe gR sMpo i it tt ac o r , eautro c r pi s r si yn ot t t te pstlk ret rs0co3 a ar Sl rreocat c o 1 ap eC t s
t o s
E e o d s a pl e tf rsdr0 ht it co uenu0 y e d
l r t c ,,b f e . e crat1 rrrr eo it a
et aer e y r y"ac e d r e
t src eeh a yV r a - et ei pepw Fc wel gepncg dd/ geee m e dpnt yii n aR%rKpg KeKd t o sat adt a ocy5 e n n 5l 0r e wMih aMoah wel n0ea 1 e1 a D TGdcb" i mc Td(+ E6T r $t$h n
o i
t s a e r "n i t
oa s i pi rd e l s
or r i e
Ca u b u t a 1 c AG a p 8i C" e a 9r G F C 1P
,ji lj
n ai c ta ta d t o o u Usf e8d r r psp or d4.ld f f neCne a en t t
._ i c gt roio u an gt f c u u p
- sd .ii p u pf s e n p
p
. g eead n srt r uo i s ame e 5 iN i
s e ,det bmn s s s) cs t u oat . s s eU onesp nrcas l e e -
cP rot yn afS c c oC pi a s o ct ea o o r( tr c nv r p .p r
P. Ua d Uu .or .
t Pt enl P psde s s l i Csraa C nn t onon S an u n i oen t ot o rU cdsmr c ibi i i M t il ore ist -
KtKt E n sepat ssane 9a0a T e aixl x aet at 3t7t S C Bf eae Bcscu $ s$ s Y
- S K
- e2 G e l$ .
N l e s I
e . tte R ty ul O r roi
)T I dt obm d N ee f a 5
t m
'tnMO ae cl ne.
or0 ii o ie C E dt t wt (M e a a I
n dF td I T o ,R srn V L- i ao s er ro rHi e t E EA s p a L R ai i B t m w , .t A as e K ys r
T OR
.F D n a
dn ro 5.
3 ee tr r Hp ah 5mp T
A .
T A - - n C D s s . e h 0 e i y r v t 5 R r d - r ce e i 2 O
D s p eeli g s wwe-or K c rl rt at r N i dea ti aa n )l us n3 E nn ebtt armh al r ti o$
V oo f nirbeoc pahta i i r oaga st sn/are tt tt o8ihr ue - gR eg as ac rcDcu ,ag si ypn t o t e p op n rs0cna sc Sl rn ph u d a o 1 aer E eo .i k nr tf rT . rs d hisr8ca co u gC er po) l r t - rt a r e c n0 eo ados ,bto tsrc .i5 te it eet r ut eeh ast5 Kcc Fc e
wzc ,eroc i e yd e d e dd/
aR%er+
ocp5 ve l a
- 3. ee 1 ep ti t ortarwat epo 1d e wuel ooee weI D Tsdpcprd Td(+ Tot -
$( a s
e k
o1 s t1 e s S0 i e 1 t c
- s i i r
y e l P
rr r i et u b a 1 t n t ue a p 8 eS e a 9 R F C 1 IT
,^ ' '
i
ne ol s at s hwe s
_ rss t d e t ya igo c wnm o sl t c i r ug dt r p pny eso g tit saf l n ul i uc a -
en r -
i s
oel di sro t
- n ?
s) rob roi eU cP t emat oft s a e
c oC r(
uos pt nrm eor F
_ P m oyn e sfo R t f nrn r m l i cl i e an t m ooi o t rU dcr it f s t l ee ti e y n ert anr K S e iie t oo 3 C Fdd Smm $
g n s -
i r - dr o l ne a av F t
n ye- ma R o rre m y M t l oe eres cm w a
l moti yt i
a ef .
c l te a s 2 ed ur l se Ii I g tebi eam r o
Vo d w r i l
yng ht f Eo aend nc L r wmir aun n Bo n - mra csa o At o 2 ooh c i i ct F ns t Te s deid . Ro ay M s ernne id t r ai t oal yt n St "D t m as amm ce ei b aaa wt
/e Km 3
D n a
it ens dsmos o
- ss wog e 5. el 3 e r e yi h o s T Dstpp Tt a $t i
c n o rd e -
t - - ren - r a o eeot ae uo p r s - l df e r t s a t
a t e e mreg al ec m ud t ns ra h p ocnt n e td i
no diieai ps n l
C n it et nTes mr ra o #t ao hu eo o i s er air o ts fs t c gedcdt . rh n e ai at niacno ,e nr t n kuadreoss rs ou So cp e l inc e . it ta .
r a me d resei wte dt po o ssn onl aes l c ee il r
ceefni ns odi u yi s r t e om,ord . pi b r pl oa tfe s
/et i
s FE sl m rt necr a i Kvi e nernt cawei l wa 0ol c ei e a e e r ol u oev 1bi i r
SftCmttteq Sda $ab p
e s
s a e h i c t r s i u e l p r i a 1 u b t a t 8 a p s 9 e a o 1 a
F C C i$*
li c
s n n e d n e n i o o n r o o am t s h
P h o a h l
e h P N H P T P an .
Da r
T s
e 5 c '
er) 6 4 2 cus 0 2 - -
noe aSl 1
- 5 1 5 6 t
5 i 5 2 0 smm io(
1 0 0 0 L Dr S f M
E T
S Y
S G
N I
R O fg T on II i
IN rrs IO VM eot bti 1 2 b c 2 6 d 8 2 8 1 1 9 ED min -
LE unU BL No M s AL e TA i T r S ot N si I
s E -
e M c I
cd al T
- li L af A n c E o i6 R i g1 t o ae 1 0 0 1 0 0 1 l
ov lt 8 8 8 8 8 l a 9 9 8 8 ra 9 9 9 9 9 oh aD 1 1 1 1 t
1 1 1 e tl s
n el I mi e
dm ue ltl cs ny i s a sd r ne e ot a m . a )
i tl n ) m s 2 ap o
y L u) I) - d t m SE d ) E so n ) & eE . . e -
y a) d .& l td r'.
t) CE eE P C d ir i . PE fl l te l k G Mo oa ee o& l . c . l - r n . nC l n l am i n iC et an O ih FW i w cO bG Sm o
wn gS ee io .
a(
aP re r( rM dC n0 i( aC eP i h( n( a5 )))
F D L( 8( V T I S( ab k:
} ( l
I 5.0 MATRIX EVALUATION One of the primary objectives of this program is to evaluate the concept and usefulness of an offsite real-time monitoring system in the light of a matrix array and associated parameters. The matrix anfits and detector sensitivity here three major components, accuracy, cost, presented in Section 1. Based on the review and studies conducted in '
the prior sections of this report our evaluation of the matrix is as l follows. For ease of reference the matrix array is reproduced on page 51 as Figure 14.
Accuracy - The accuracy level was evaluated based on the uncertainty associated with the quantification of an unmonitored release in the presence of a moni-tored release. Based on our study we propose eliminating all conditions associated with accu-racy values for factors of 2, 5 and 10. In some l cases, especially for the case where the unmoni-tored release is small conpared to the monitored release, even the accuracy factor of 50 for the unmonitored release may be a question.
Detector Range - The requirement for detectors sensitive to the ,
measurement of a quantity of radiation equivalent to 0.1 background (1 pR) cannot be justified, especially when the background can fluctuate more than this amount. A similar argument can be made for detector systems having a lower range equiva-lent to background (10 pR/hr) because the un-certainty in the signal would be large and a reading equivalent to background in an emergency situation would not be significant relative to the initiating protective action in the surround- f ing areas. One might make a case for the use of detectors having a lower range of 10 pR/hr in establishing site specific diffussion models based f l
1
-4 8-
X 1
.. o on the monitoring of normal releases. However, .
if the detectors are placed at a two-mile dis- $
tance from the plant, the dose rate from normal releases would be so small. as to be garbled in i
the normal' background fluctuations. In our opinion, detectors with a lower range of 10 times the background level or 0.1 mR/hr ould be adeouate for an offsite real-time monitoring system, because readings of less than 0.1 mR/hr are of little significance from a hazard stand-point. This is a point which should be pre-sented as part of the public relations effort of the utility. This conclusion eliminates the two lower levels of the matrix.
Cost Factors . This item is more difficult to assess because of the wide range of values associated with the installation costs. We can, however, make some general comments. If a low cost system is in-stalled with a minimum (8-12) number of sta-tions, there is a high probability of missing a plume, in which case the system has little I
technological value. To install a minimum sys-tem with detectors only near population centers may have appeal from a public relations stand-point but it does not provide the technical
' data which is necessary to assess the impact of a plume to the rural areas which could be popu-lated by grazing milk cows. Also, if the detectors were not uniformaly spaced near the population centers, f alse information relative to the intensity of the plume dose could result.
l 1
-.We do not support th'e installation of a. minimum system, which'we are associating with a $250,000
' cost- value, because the technical -information .
obtained from such: a system would be of ques; tionable use in a. decision making proces I.
Similar argtsnents can __ be made' for a $750,000 system; however, at this level each installation would have to be evaluated on an individual basis because of site specific characteristics.
Obviously the requirements for a monitoring system in a flat terrain situation is.different from one involving water, off-shore and on-shore breezes- etc. In some cases, a system : con-structed for a cost of $750,000 might provide
' reasonable technical information. . Thus, we have decid'ed to leave this area of the matrix open but emphasize the site specific character- i istic of the case. '
For $2,000,000 one might construct a reasonable j system, but in no case would information accur- <
ate' to a factor of 5 or .l0 be 'obtained. In }
fact, almost no sum of money would insure ob-taining dose values to this level of accuracy.
Based on the above' discussion and evaluation, the bulk of the matrix has been eliminated. The remaining areas which we feel identify the potential benefits and associated uncertainties from the installation of a fixed.off-site real-time monitoring system are shown in gray in Figure
- 14. While it is acknowledged that our conclusions are argumentative, we believe they are representative of the current state the of art.
1
i
/ ,
/'
///
/
e e
r s
r e
c i
XlA /
/
0 _
5 W/
2 s
/ X 0
5 t
r e
e m
a r
a
/ / X ro 0 y 1
t F
c a
c P
i t
M x
r a
X ar .
u
// 5 X
c c
A 4
1 i
F e
r u
g
// 2 X
a
'f~/ r h
/
R h
/
R p
r r h
/
R y
0 0
- 0 0 1 0 1 0
1
- ,$x h sT '
I l ; L' l
- l 6.0 MINIMUM-COST EMERGENCY SYSTEM 1
. i An augmented effort to the general program involved the chcracteri- 4 zation and evaluation of a specific, minimum cost emergency system with ]
close proximity to the plant. f The constraints to be applied to the eval-uation of such a system are as follows:
1.
Total system cost - not to exceed $500,000, 2.
Detector assembly cost - not to exceed $7,000/ unit 3.
Detector distance - no further than 800 m (0.5 mi),
- 4. ' Detector sensitivity - 0.1 mR/hr to 10 R/hr, and
- 5. Accuracy - within a factor of 10.
Using the cost data presented in Section 4, the following values were used to establish the magnitude of the system which could be instal-led within the $500,000 constraint.
_ Fixed Costs Central Processor (with modeling, $110,000 48 station capacity)
Design and Engineering 40,000
$150,000 This leaves a balance of $350,000 which can be allocated to the cost of the detector assembly, data transmission, and installation. The cost per station is estimated as follows:
. - - - - - - - - - - - ~ - _ _ _ _ _ _ _ _ - - - - - - - - - ' ' - - - -' ' '
$ 7,000 I
.Dectecter Assembly i a 8,000 Data Transmission / Unit b
3-15.000 Installation / Unit Total / Unit $18-30,000 7 1.
- Includes capital cost and installation b highly variable depending on specific location i
For this exercise it was assumed that the data transmission involve a telemetry system because the cost of installing hardwired or For example, climatic fac-dedicated phone systems is highly variable.
' tors may dictate the burial and/or the use of special materials in each of these data transmission systems. The installation costs are based on If uniform placement simple units all installed on flat solid terrain.
of the detector assemblies required installation in cooling ponds, riv-ers, or other bodies of water, the installation costs would increase significantly, perhaps by as much as a factor of five for those units in Another significant expense item is the power source.
such a location.
If an uninterrupted power supply from the Auxiliary Building is used the cost per station would be significantly more, especially if underground or underwater lines were used.
which can be allo-Based on an after fixed-cost balance of $350,000 cated to the detector units, and a range of average station costs of units could be installed
$18,000 - $30,000, from 12 to 20 detector depending on tne actual placement of the units.
The 12 unit system would insure eaual placement of the units rega The 20 unit system could have voids in the moni-less of the location.
toring grid and be operated with normal power sources.
The' estimate appears reasonable ' based on information obtained from two utilities which provided cost information for a comparable system.
One station which recently completed installation of~an 8 unit system at
, a distance .of. 800 m (0.5 mi) ouoted a cost of about $435,000 for the.
purchase' and installation 'of the package. In.this case, each' unit also included a meteorology station and the output from the unit w% hard-wired to the control station and coupled to an existing HP-IdOO data -
processer. .Thus, the total cost per unit is~approximately $54,000.
The overall cost would increase if a dedicated CPU were used and probably decrease' if some other form of data transmission were used.
The cost per unit would also decreasing if meteorology sensors were not-installed with each unit, but the validity of any down-wind projection would also decrease.
A.second utility while not providing complete capital cost data did provide sufficient information to estimate the cost .for a ring of nine units at a - distance of 1000 m. The. central processing unit for : this system has not been purchased. However, the purchase cost of the nine-field stations was about $135,000, or about $15,000 per station. For the nine unit system using a dedicated phone system for data transmis-sion, the installation cost per unit was ouoted at about $23,000 per unit or about $200,000 for the system. This is somewhat higher than our estimate but give some idea of the costs involved just for installation.
l- Assuming fixed costs of $150,000 for design, engineering, and a central data processer, about $135,000 for instrumentation and $200,000 for in-sta11ation gives a sum within the $500,000 constraint. The unit cost for the nine detector system is about $55,000, which is similar to the first system discussed.
To estimate the credibility of the data which could be expected from an 8 to 20 unit system we first considered the data given in Table V. Based on these data, a minimum of #90 eaually spaced sta-tions would be required for two adjacent units to give a reading within I
a factor of 2 of each other when the release was at ground level L
N _ _ _ _ . _ _ _ _ _ _ _ _ _ - ___ ____ _ ______ .. _--_ _ -
L .,
p L - 'and the stability class was F. For two units to agree within a f actor L 'of ~10. would require a system of. 35-40 units. About 30 detectors would be reouired for more common class D weather. These numbers are based on the assumption that the centerline ~of the plume passes directly over one The passage of a of the stations. This is a highly unprobable event.
plume between two detectors would give a response which underestimates the true magnitude of the release.
A second factor which must be considered for a 500-800 m system, is
-the' effect of the building' shine f actor, especially for a BWR. - For the case given in Figure 12, the plume dose at 800m for a leak rate of 1%
. per day of. the building noble gas : inventory is considerably less than the building shine background. The effect of building shine will be much less for a PWR.
The effect of building wake and dispersion ' of the flow regime by other buildings (other than the reactor building) is a third f actor which should be considered. This' effect could significantly alter the mea-surement of the true' dose from the plume.
While a- close-in detector system might in some instances provide
- some information in an emergency situation, the ability to extrapolate and project the information to give concentration or dose values at some extended downwind distance (5-10 mi) is highly questionable. This could only be done with a reasonable' degree of confidence if site specific
- modeling and additional downwind meteorological data were available.
1 l
l i
l i
x
7.0 REFERENCES
1.- F. Pasquill, "The Estimation of .the Dispersion of Windhorne Material," Meteoro1. Mag., 90:33-49 (1961).
- 2. U. S. Nuclear Regulatory Commission, " Proposed Re' vision 1 - to Regulatory Guide 1.23, Meteorological Programs in Support of-Nuclear Power Plants" (Sept. 1980). 'T
- 3. D. H. _ Slade (Editor), " Meteorology and Atomic Energy-196 ,'" USAEC Rept., TID-24190, Environmental Science Services Administration (1968).
- 4. I. A. Singer, M. E. Smith, " Atmospheric Dispersion at Brookhaven National Laboratory," Air and Water Poll. Int. J.. Vol. 10, pp 125-135 (1966).
- 5. J. L. McElroy, F. Pooler, "St. Louis Dispersion Study Volume-II-Analysis," U. S. Dept. of Health, Education, and Welfare, Arlington, Virginia (1968).
- 6. 'K. J. Vogt, H. Geiss, " Tracer Experiments on the Dispersion of plumes over Terrain of Major Surface Roughness," JUL-1131-ST, Julich (1974) see also Ref. 7.
- 7. K. J. Vogt, " Empirical Investigation of the Diffusion of Waste Air Plumes in the Atmosphere," Nucl. Technol. 34:43-57 (1977).
- 8. H. D. Brenk, " Atmospheric Dispersal," Lecture prepared for the Third Annual Health Physics Society Summer School at the University of Washington, Seattle, WA (1980).
- 9. C. V. Gogglak, H. L. Beck, M. M. Pendergast, " Calculated and Observed oDKr Concentrations within 10 km o the Savannah River Plant Chemical Separations Facilities," Atmospheric Environment, Vol. 15, pp.497-507 (1981).
- 10. R. O. Chester, C. W. Miller, ORNL Unpublished Data, Breeder Program Technical Status Rept. (August 1981).
- 11. F. Owen Hoffman, Gen. Chairman, " Proceedings of a Workshop on The Evaluation of Models used for the Environmental Assessment of Radionuclides Release," CONF-770901, Gatlingurg, Tennessee (September 1977).
- 12. Isaac Van der Hoven, W. P. Gamm111. "A survey of Programs for Radiological-Dose computation," Nuclear Safety, Vol. 10, No. 6 (1969).
- 13. C. D. Thomas, Jr., J. E. Cline, P. G. Voilleaue, Evaluation Of An Environs Exposure Rate Monitoring System for Post-Accident Assessment, Draf t Report to AIF Science Applications Inc., Nuclear Environmental Services, (Sept. $981).
I
e REFERENCES (cont'd).
- 14. U. S. Nuclear Regulatory Commission, NUREG-74/014. Reactor Safety Study - An Assessment of Accident Risks in U. S. Commercial Nuclear Power Plants, (Reprint of WASH-1400), (1975).
- 15. R. L. Engel, J. Greenborg, M. M. Hendrickson, ISCSHLD - Computer Code for ' General Purpose Isotope Shielding Analysis, BNWL - 236 7
(1966).
l.
\
f
, .. - - . - . . . _ - _ _ - _ . . - - _ - _ - - - . _ - _ - . _ _ - . _ _ - _ _ _ - _ _ _ _ _ _ _ _ - - _ _ - . _ _ _ _ - . . , _ _ = _ _
.. I hk l.
APPENDIX - A BRIEF
SUMMARY
OF EXPERIMENTAL RESULTS TO'-
COMPARE. MEASURED AND PREDICTED GROUND LEVEL CONCENTRATION VALUES i
o A.1'. 85Kr Experiment at Savannah River Plant 9 85 In this experiment, the release of Kr from the Savannah River Plant chemical separations facility was monitored for over a yyr at six sites within 10 km of the release points. Using the Gaussian ppme mode: 1 for a continuous source, the ratio of the predicted concentration to the measured concentration was determined. The dispersion parameters were those based on the ideal case of flat terrain, short distance, and steady meteorological conditions.
The general results showed that the annual ' average concentrations were over-predicted by a factor of 2 to 4 compared to the measi red values. For the short-term (10 hours1.157407e-4 days <br />0.00278 hours <br />1.653439e-5 weeks <br />3.805e-6 months <br />), the predicted values were within about a factor of 10, and in many cases, particularly in calm or stable conditions, measurable concentrations were predicted when none were ob-served. The results of the short-term data are shown in Figure A-1 from Reference 9.
A.2 ORNL Assessment of Hanford Experiment 10 As part of a DOE sponsored program associated with the Breeder Reactor Program, ORNL is evaluating experimental data obtained from an experiment conducted at Hanford in which zinc sulfide fluorescent parti-cles were released from a height of 111 m over relatively smooth terra n.
Crosswind-integrated ground-level air concentration measurements were _
compared with predicted values using a Gaussian plume atmospheric dis- ,
persion model. Of interest was the use of three different sets of mea-surements to calculate the atmospheric stability class.
- a. The vertical temperature difference between 10 and 122 m above ground-level, )
- b. The standard deviation of che wind direction measure at a height of 122 m, and A-1
4 i
Composite Of All Locations 3 .
I. I 10 4 i i a
/
' /
/
/
/
/
/ '
/
3 -
/ , ,
10 /
,e /
~ /
'l
.' s
/
/
l N * / , /
c . /
/ - ,/
- p ,
/
oa. ri. .
2 f
/
~ 10 je ' f , ,* ,' 1'
.5 t.
- , n
's
/
- / s 8' /
3 .
2 / * *.. /
l 0
a
/
/* *
' ;/
1
/ . ','-
. g, -
10 . . . .,
f.,
. e ** /
'l . .. /
.,t,
,/ , ,
/
/
- / ' -
0 - -
10
- 10 0 $b1 $b2 jb3 10 4
- Measured (pCl-h/.t)
ICPP.S 7924 i
85 Figure A-1. Measured to Predicted Kr Concentrations (ref. 9)
A-2
- I
.f
- f. ,
d . _ _ . _ _ _
4
- c. A combination of a and b.
1 For'the Hanford data, methods a and b, with.one exception, indicate Pasauill stability classes E^ or F, while method c always indicates class D.
T In' this study ORNL compared the results obtained as a fu ion of-
. the di spersion . factor, o,, based on five different sets of diffusion
. model s. Basically, these include those data sets previously discussed and reviewed by Brenk0 (Pasauill, St. Louis. Briggs' Rural, Brookhaven, and Julich-100 m). Separate comparisons were made between measured and predicted concentration values using each 'of the five sets of o g values and three stability class determinations. A summary of the ob-served and predicted concentrations values is given in Table A-1.
These data-(Table A-1) show that the predicted values differ from the measured values by a factor of 5 to 10 more than 50% of the time and that the predicted value may be more or less than the measured value depending on the dispersion system used and the associated dispersion factors. About 40% of the time the difference between the predicted and observed values can be a factor of 10 or greater; again in either direction.
These data tend to support our initial comments regarding uncertain-
- ties associated with the use of the standard Pasauill factors and the need to develop site specific data.
A.3 Excerpts from a Workshop on the Evaluation of Models Used for Environmental Assessment of Radionuclides Releases ll The working group suggested some tentative accuracy statements on the estimation of airborne concentrations. These statements are largely based on scientific judgement; there are not enough data upon which to base a reliable statistical estimate. For the ideal situation of a high-ly. instrumented flat-field site from which previous data on meteorology A-3 i
_1" -
d
_ n u
o 1 r 3
_ g 1 d.
e sd v
o b e . .
b orpbesd a .or p m e. ,
P P P P P 2 i .
U U U O O 2
( i
(
1 s m
e s s r d 2 u e t e n 2 l u i t a 1 a l
, m a v a
._ L i e } % % % % % 0 f v N L r o 8 8 3 2 8 1 o d R G (' 3 3 3 5 3 e d O
g n t v e n r e h r v Y
i o e g e r B d w i s e e 0
- t e b s T e 1
- e h o b N c P P P P P b o E x r U U U O O a o M E o e t o I c t t R s r n a e E n o e v e P o t r d i v X i c ) % % % % % e e t i E t a a 3 8 9 2 3 f r a t a F ( 4 3 2 5 4 f u l a D v i s e l R r d a r e O e e r F s e m n b o n N
A O r
u n o
i t i o
. H f t i a t
._ o r a t r a
_ F e r c t r
. O % t e e n t p r e n
_ N a ) % % % % % m O e b 2 7 8 2 2 e i c e r ( 5 5 4 5 6 t d n c I
T G o n A d c o U r l a n c L o c i l e
2 A w l V 5 i
t v e E r e e v f e h l e o v t d
l r f n d
_ 1 o n o u n t o o u A c ) % % % % % n r o e a a 2 2 3 2 2 d e
o g r g
F ( 6 6 4 6 6 i l s t s
_ b a a s.
a b i T v ie ce s e dm im s d ei di a rt et l d p r t c r rf f n y a eo ro e ny vy e d
- d m ) t n n d h i a ut ot g r t l . t i i i o i ) il s lr 1r s f m l m be eo eo s f S a av e dj qJ A i ( r 0 t e h oa oa G u n 0 Sl T Mm Mm
_ y - s r e 1 t l i v (
i* u a - -
- 'sg l
l d i o h h io u L k c ) ) P P bh q 9 o i a b U O at s . 1 o l ( (
t e a t r r u
- SM P S B B J * *
{
t
a' and airborne' concentrations . were available it should be possible to
. estimate to within 120f, the ground-level centerline concentrations from a continuous point source at downwind distances of less than 10 km.
For a specific hour and downwind receptor point, the aceyracy is very dependent on the calculation of the exact plume trajectory gjuring a short period. ' For flat terrain and relatively. steady meteorological conditions and distances of 10 km or less, the airborne concentrations for an individual case should be estimated to within about a factor of 110. For annual average concentrations values, the accuracy _ estimate is about a factor of 2.
For a~ complex terrain.or meterological situations.(e.g., sea breeze.
regimes) a few experiments have indicated departures from estimates from the Pasauill-Gifford curves of more than a factor of 10. However, there are insufficient data upon which to base even a " scientific judgement"
. estimate of accuracy.
A.4 Results of a Survey of Programs for Radiological' Dose Compu-tations U A standard accident release problem was presented to several nuclear facilities with the reauest that the cloud gamma dose be calculated as a function of distance. The same input data were used by all participants.
The results of the various calculations using identical input are shown in Figures A-2 and A-3. The range in the calculated values is a factor of e10 at the 1000-3000 m distance. Considering that there are no absolute standards by which t > judge the accuracy of the dose calcula-tions, one might ouestion, "how close is the range of values presented by these calculations to the true absolute value?"
A-5
,4 106 I I
\ l I I 'N
\ f.
's
- N g B,G,J s
5 105 4 _
s s s
s
,,3~ N s's "*
s
' %,)
\ .N \'
10 4 - -\- H\
\ "
\
j
'l.g. ..N,s. \ \
t
- \\
x \
$ '* ? .,, .\ \p 10 3 _ .,
g, _
r.' .,.
B j g gG,J D
g E
\'
Cloud Gamma Dose A 10 2 K -
Type F 1 m/sec 1-hr Release, Ground Source Inversion Conditions I I I I I I 10 500 1000 2000 5000 10,000 100 200 l Distance (m) l ICPP S 7925 Figure A-2. Comparison of Different Dose Calculation Models, Class F (ref.12)
A-6
4 103 1 I I I I I 7 Cloud Gamma Dose Type C 4 m/sec
\
102
\
g 24-hr Release, Ground Source ,
\ N eutral Conditions s
i \
\
\
10 7
E i'
' \
i ' s. \ \
i 1 =
.\
.\
\ =
\
\
s \ -
10-1 - g. \G ~
ss A B, l
.E K 1 1 1 I i H 10-2 100 200 500 1000 2000 5000 10,000 Distance (m)
ICPP S 7917 Figure A-3. Comparison of Different Dose Calculation Models, Class C (ref.12)
A-7 l
o a
7 l.
APPENDIX B
> VALUES FOR o,AND o USED g IN DOSE CALCULATIONS l
l t
-. - - - - _ _ _ _ _ - - _ - - - - - _ - - - - - - . - l
9 0 6 n
r 2 2 7 7 4 2 o 8 9 1 e m r e
f 0 e 0 R t 2
3 c n i i r 6 9 3 4 1 5 n e
t s
e A*
y 8 4 1 0 5 0 o 5 4 3 2 1 1 v r
- i g n a
a c t
a )
b d m 0 0 3 8 9 5 1 9 e 0 r 5 7 9 4 3 1 h 0 m o 1 2 t 1 a t (
S 0 i N 0 f h O 6 1
t I
T o p e
t A d L e )
U c 9 8 1 6 3 r C n y 2
3 7
6 0 8 5 1 e L a 1
( y A t o 3 2 1 1 d a C s e l i
p E D o g S l n 0 e i 0 v x 1 N e i
- I d m B 8 4 7 0 2 n e D 6 1 o h E E z 2 9 5 2 2 t
L S a 3 i t
B U a e A m u s T z a u o 0 0 e a O 8 c N
n e A
a b y n c o 4 5 8 7 3 0 o i y 6 2 8 5 4 3 t o 1 1 d s R e i O s l F a a S b e E
r s
U e t L
A u o V 8 3 5 9 4 9 l n r 2 5 3 1 1 a o 1 v e m r d a 0 e 0 t 0 5 a 0 l 0 .
u 1h 6 0 7 7 8 9 c t y 0 8 5 3 2 1 l nw o 1 a ao c hr t g e
r re a em t u a al ep t
a rge d
l d sc y e ei t t ut i s l r l
i ae is A B C 0 E F L Vv bs aa tl a b SC
}
' O'OI" U.S NUCLE AR REcuLATCGY COMMISSION
N
' BIBLIOGRAPHIC DATA SHEET
- 4. TITLE AND SusTITLE (Add Volume No., slappropriew/
h
- 2. (Leere ble&1 h644 An' Assessment of Offsite, Real-time Dose Measurement Systems for Emergency Situations 3. RECIPIENT'S ACCESSION NO.
- 7. AUTHOR (S) 5. DATE REPORT COMPLE_TED M ON TH hYE Am W. J. Maeck, L. G. Hoffman, B. A. Staples, J. H. Keller March 1982
- 9. PE RFORMING ORGANIZATION NAME AND MAILING ADDRESS (inclusir Z$ Codel DATE lEPORT ISSUED Exxon Nuclear Idaho Co., Inc. "oN'#. Ive^a P. O. Box 2800 ADril 1982 Idaho Falls, Idaho 83401 s.(te m ai- */
e.(te m W ans ,
- 12. SPONSORING ORGANIZ ATION NME AND MAILING ADDRESS (incluse le Codel ,
Division of Systems Integration Office of Nuclear Reactor Regulation- 11. CONTRACT NO.
U.S. Nuclear Regulatory. Commission NRC FIN A6461~
Washington, DC 20555
- 13. TYPE OF REPORT PE mioD cove RED (inclusive dews)
Technical September 1981 - March 1982
- 15. SUPPLEMENTARY NOTES 14. (Leave We&J
- 16. ABSTRACT 000 words or Jess)
An evaluation is made of the effectiveness of fixed, real-time monitoring systems around nuclear power stations in determining the magnitude of unmonitored releases.
The effects of meteorological conditions on the accuracy with which the magnitude of.
unmonitored releases is determined and the uncertainties inherent in defining these meteorological conditions are discussed. The number and placement of fixed field detectors in a. system is discussed, and the data processing equipment required to convert field detector output data into release rate information is described. Cost data relative to the purchase and installation of specific systems are given, as well as the characteristics and information return for a system purchased at an arbitary cost.
- 17. KEY WORDS AND DOCUMENT AN ALYS!$ 17a. DE SCRIPTORS Offsite, Real-Time Dose Measurement, Emergency 17b. IDENTIFIERS /OPEN-ENDE D TERMS
- 18. AVAILABILITY STATEMENT 19. SE CURITY CLASS (This report) 21. NO. OF PAGE:
Unclassified Onlimited 2a Sggi,TgyfggTh,,,eni 22. P RICE l NmcFORM 335 17 77)
- y ,
7 ' *a j pga n8o -
- *. NUCLEAR RE UL ORY COMMISSION c
.S. '
-y WASHINGTON. D. C. 20566
- 7. .
g *- *+++
eDO Principal Correspondence Control U y 47 j' j
.FROM:
DUE: 04/07/89 EDO CONTROL: 0004371 DOC DT 03/22/89 FINAL REPLY:-
S:m. Barbara A. Mikulski &
S u n .. Paul'S. Sarbanes 1
'TOs Chairman Zech ,
FOR SIGNATURE-OF: . ** PRI ** CRC NOi 89-0281 {
J Chnirman-Zech ]
.1 ROUTING: j DESC:- .q Et -
RESTART OF' PEACH BOTTOM Stello g Tayl or :. 1
' DATES 03/30/89 Thompson B1aha ASSIGNED TO - CONTACT: . Russell, RI Murley Beckjord, RES
, .iNRR. _,
' SPECI AL- INSTRUCTIONS OR FEMARKS:
HRR RECEIVED: MARCH 30, 1989 ACTION: qDRPRj,[AINAS(
NRR ROUTING: MURLEY/SNIEZEK MIRAGLIA VARGA CRUTCHFIELD GILLESPIE ;
MOSSBURG q l
a