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Forwards Proposed Revisions to FSAR Section 14,App B, Evaluation of Purging as Means of Controlling Post-Accident Reactor Bldg Hydrogen Concentration to Be Incorporated in Next Amend,Affecting Purge Flow Rates & Length of Times
	ML19308D675
Person / Time
Site:	Crystal River
Issue date:	12/09/1976
From:	Rodgers J; FLORIDA POWER CORP.
To:	Stolz J; Office of Nuclear Reactor Regulation
References
	NUDOCS 8003120773
	Download: ML19308D675 (16)
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, 1 Docket No. 50-302

, i Dear Mr. Sto 3 In reference to FSAR Section discussion on " Purging for Control Hydrogen Con-centration", we propose to revise certain pages to our FSAR.

Attached are the affected pages 14B-V, 14B-3, 14B-9, 14B-13, 14B-19, 143-20, 14B-23, 14B-24, 14B-35 and figures 14B-6.4 to 14B-6.2, 14B-6.5 to 14B-6.3, 14B-6.6 to 14B-6.4, 14B-6.7 to 14B-6.5 of the revision to the FSAR Section 14 Appendix B entitled "An Evaluation of Purging as a Means of Controlling Post--

Accident Reactor Building Hydrogen Concentration" to be incorporated in the next amendment. This revision affects only the intermittent purge flow rates and length of purge times and does not violate the appropriate Codes and Regulatory Guides. Figures 14B-6.2 and 14B-6.3 have been deleted, as these figures are not applicable to the changed intermittent purge conditions.

As in past procedures, these noticed changes are effective i= mediately and arc so implemented. The next amendment to our Crystal River #3 FSAR will incorporate them by appropriate change procedure.

With this submittal the item is considered closed but should you have questions or need anything further, please advise us immediately.

Very truly yours, I

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LIST OF FIGURES (At Rear of Section)

Figure No. Title 1bB-5 3A MHA Thyroid Dose at Low Population Zone (1500 GPM RB Spray Flov) lhB-5. 3 B MHA Thyroid Dose at Lov Population Zone (1200 GFM RB Spray Flow) 1hB-5.h MHA Whole Body Dose at Low Population Zone 1hB-5.5 LOCA Dose Sensitivity to Hydrogen'G-Value 1bB-5.6 MHA Dose Sensitivity to Hydrogen G-Value lhB-5 7 LOCA Dose Sensitivity to Z -H 0 Reaction r 2 lhB-5.8 MHA Dose Sensitivity to Z -H 0 Reaction r 2 lhB-5.9

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Hydrogen Purge Flow Diagram lbB-6.1 Crystal River Accident Meteorology 152 f. Ir.tc s itt;r.t h rg; "ct;;r.1;gy

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m 21c 2 lhB-6.& 2. Thyroid Dose Probability 1hB-6.9 3 Thyroid Dose Probability Distribution 1hB-6. 4 Whole Body Dose Probability Distribution lhB-6.7 5 Dose Probability Distribution Using Regulatory Guide 1.7 l Apsumptions i

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.' flow. Fcr th2 spray flow r duction, the mora conservative etse of a constant 1200 gpm spray flow v s essum:d; otherwise, a constant spray flow of 1500 gpm was used in the analysis to determine the reactor building airborne iodine concentration.

. Analyses of both intermittent and continuous purging at the Crystal River site indicate that intermittent purging would be expected to result in much icver doses than continuous purging. Table lhB-2.1 shows a comparisen of the results obtained for intemittent and continuous purging. The initial contin-uous purge rate for Regulatory Guide 1.7 assumptions utilized in arriving at the whole body and thyroid dose calculations shown in Table lhB-2.1 was 2.8% of the containment volume per day or 38.9 SCFM. Purging was assumed to start at 250 hours0.00289 days 0.0694 hours 4.133598e-4 weeks 9.5125e-5 months after the MHA using Regulatory Guide 1.7 assumptions and was allowed to gradually decrease in time.

12.0 Intermittent purging was assumed to occur for a maximum of Z minutes in any l 2h-hour period. Furthermore, purging was assumed to be initiated only when vinds were blowing in an offshore direction. Continuous purging was assumed to start at 1500 hours0.0174 days 0.417 hours 0.00248 weeks 5.7075e-4 months after the LOCA and 980 hours0.0113 days 0.272 hours 0.00162 weeks 3.7289e-4 months after the MHA while inter-mittent purging was started 312 hours0.00361 days 0.0867 hours 5.15873e-4 weeks 1.18716e-4 months earlier to account for the possibility of persistent onshore vinds.

Because of the inherent advantage of attempting to utilize the high frequency of offshore vinds, the preferred mode of purging is intermittent. The alter-

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native to containment purging (continuous or intermittent) is the use of recom-biners for post-accident hydrogen centrol. McVever, the resulting off-site incremental doses due to post-accident hydrogen control by purging for Crystal 2, River Unit 3 are so lov, even when evaluated on the very conservative basis suggested in AEC Regulatory Guide 17, that Florida Power Corporation does not believe that the addition of a recembiner system as either a primalr or backup means of control is warranted. Further, the potential for malfuncticn of a recombiner system and the possible serious secondary effects which might be produced in such an event cannot be justified in light of the lov doses that are projected as a consequence to operation of a simple and highly reliable purging system. Florida Power Corporation further believes that the favorable meteorological conditions at the Crystal River site can be used to allow intermittent purging to reduce the probable projected off-site dose.

The analyses presented in this appendix demonstrate that controlled purging can be utilized to maintain hydrogen cencentration below flammable limits without delivering excessive total doses to the public. The projected incremental whole body do.Ms for both the MHA and LOCA as a result of purging are considerably less than the average annual natural background of 125 mr in the Crystal River area. Even vten the extremely conservative Pegulatory Guide 1.7 assumptions are used, the projected incremental whole body denen are expected to be less than -1", of 10 CFR 100 limits. In all cases donc en.lculat.icns were made using conservative assumptions.

Both continuous purging and intermittent purging which utilizes favorable wind directions have been examined. Based on a comparison of the results, inter-mittent purging has been selected as the preferred purging method. Calculations have also been made in accordance with the assumptions given in AEC Regulatory Guide 1 7 and are also shown in. Table lhB.2-1.

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.' which tra- felt by' the rIgulatory staff to be c6nservative for the various para-meters aff&cting post-Iccidsnt hydrogtn accumulation. The assumptions given in

'the guide which are more conservative than the assumptions used in lhB.3 1.and lhB.3.2 are as follows:

a. The fraction of fission product gamma energy in the fuel rods absorbed in_the coolant is 0.1,'(calculations indicate that the fraction should vary with time from 0.lk to 0.08).

.b. The fraction of zirconium cladding reacting with water is 0.05, (calculations indicate that 0.01 is conservative).

c. The radiolytic hydrogen yield, G(H2 ), is 0 5 molecules of hydrogen per 100 electron volts of absorbed energy in the core and sump water, (Experimental evidence indicates that G(H ) = 0.3 for the sump water). 2 To obviate selecting from a range of alumihum corrosion rates as recommended by the guide, the complete reaction of 1000 lbs of aluminum was assumed. Using these modified assumptions, purging must start at approximately 250 hours0.00289 days 0.0694 hours 4.133598e-4 weeks 9.5125e-5 months after the MHA. Figure lhB-3.8 shows the containment building hydrogen concentration as a function of time following an MHA using Regulatory Guide 1.7 assumptions.

If continuous purging were started at 250 hours0.00289 days 0.0694 hours 4.133598e-4 weeks 9.5125e-5 months and continued far a period of two months, the dose increment at the low population zone distance due to purg-ing would be 2h8 mrem.to the whole body and 581 mrem to the thyroid.

IhB.h EVALUATION OF PURGlNG FOR CONTROL HYDRCGEN CCNCENTRATION 1hB.h.1 DISCUSSION OF PURGING CONCEPT The controlled purge concept may be utilized for post-accident hydrogen cen-trol because hundreds of. hours are available for fission product decay before the purging starts. The preferred purging approach evaluated herein is to allow the hydrogen concentration to increase until the control limit of 3 5 i vol". is reached at the projected time of 313gurs; then to purge during g {

periods of off-shore winds for a maximum of ---minutes each day at a rate that J just compensates for the hydrogen being generated.* Therefore, the maximum {

delay for fission product decay is obtained, and a decrease in purge rate re- {

sults as hydrogen generation rate decreases. This method minimizes the expected radiation dose-to the public. Continuous purging (as opposed to intermittent purging) is also considered to be capable of satisfying the requirements of hydrogen control with minimal risk and is also evaluated herein.

In order to specify purge requirements, those conditions that control the contin-uous . purge. starting times and the necessary rate of continuous purge are established as follows:

Advancing the time of intermittent purge initiation by 312 hours0.00361 days 0.0867 hours 5.15873e-4 weeks 1.18716e-4 months allows for the possibility of as many as 13 days during which there may be no offshore vinds.

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, Addin6.these marginc nether, a totid mnrcin of' O.6 v. / (r.pproximately 12000 ft3 )

hydro 6cn is obtained. Thus it~is established that a conservative control purging s:;t point of 3 5 vo1% provid;;s Edrqunto margin bntwun the control limit and tha

h. . lower limit of flammability.

IhD.h.h RF. ACTOR BUILDING HYDROGEN CONCENTRATIONS WITH CONTROLLED PURGING lhB.h.h.1- During the LOCA Conditions Combining the sources of chemical hydrogen with the radiolytic hydrogen from Figure lhB-3 5, the time-dependent hydrogen concentration in the reactor build-ing following a LOCA is obtained and presented here in Figure lhB h.2. With no purging the hydrogen concentration vill reach 3 5 vo1% in 1500 hours0.0174 days 0.417 hours 0.00248 weeks 5.7075e-4 months (63 days).

The capability to further delay purging is indicated on this figure by the dashed line stalt.ing from the purge start point. Another 1100 hours0.0127 days 0.306 hours 0.00182 weeks 4.1855e-4 months (h6 days) are required without purging before the h.1 vol% limit is reached. This demon-strates that the low hydrogen generation rates require long periods of time to significantly affect the existing hydrogen concentration at 1500 hours0.0174 days 0.417 hours 0.00248 weeks 5.7075e-4 months .

The average daily purge flow required is a function of the building hydrogen con-centration and the hydrogen generation rate. The hydrogen ceneration rate de-creases with time, thereby decreasing the required average daily purge rate. Thus, the amount of purging is minimized to that amount which is necessary to control the

' hydrogen. For the LOCA conditions, the initial average daily purge rate is approx-imately 8 SCFM (0.6 vol% per day). The initial intermittent purge rate must be higher than this v since intermittent purging vill not be continuous but vill be allowed for.only _~ minutes in any 2h hour period and because intermittent purging is to be initiated sooner than continuous purging when hydrogen generation rates are higher.

A major factor that affects this analysis is the radiolytic hydrogen generation ;

rate. -The effect of varying the energy deposited in the coolant or the G-value '

is best expressed by the change in the time to start the purge as a function of the seneration rate. Figure lhB h.3 shows a plot of continuous purge start time as a function of the hydrogen generation rate constants. It can be seen that large variations can be tolerated without forcing the continuous purging start time (a major radiological dose controlling factor) below h15 hours, the start time which results if the G-value were twice the assumed value.

lhB.h.h.2 During the MHA Conditions l Hydrogen buildup has also been examined for the MHA. Figure lhB h.h shows the higher radiolytic hydrogen generation with the concentration reaching 3.5 vo1%

in 980 hours0.0113 days 0.272 hours 0.00162 weeks 3.7289e-4 months (hl days) as compared to 1500 hours0.0174 days 0.417 hours 0.00248 weeks 5.7075e-4 months for the LOCA. The time to reach h.1 vol% vith no purging is 16h0 hours as compared to 2600, hours for a LOCA. The initial purge rate required for this accident is higher than for the LOCA because of the earlier start times when hydrogen generation rates are greater. The MHA requires an initial average daily purge rate of 13 '3CFM nn compared to 8 SCFM for the LOCA. HovcVer, t.h t n purge- rnte at:m drerennen wit.h time.

The sensitivity of the MHA purge starting time to the hydrogen constant is shown on Figure lhB h.5 Because the combination value for the generation 1hB-13 Am. 38 (3-25-Th )

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Tha tho hydrog;n purga system mnts tha single fe.ilure critcrion (IEEE) in that

-; in;trum;ntation is d; sign;d so that a single cvent cannot r esult in multiple failures that would prevent the required protective action.

IbB.5.h.h Reactor Building Ventilation System-(MI)

The parallel flow paths rejoin and discharge to the normal reactor building purge exhaust duct downstream of the outside purge isolation valve. The discharge then passes through the purge exhaust filters (roughing, HEPA, and charcoal) to the plant vent via the purge exhaust fans. A radiation monitor (RM-A1) samples the discharge, lhB.5.h.5 System Instrumentation Hydrogen is monitored with a combustibles analyzer, calibrated for hydrogen, with range. a range of 0 - 5 percent combustibles and an accuracy of 2 percent of Radiation is monitored in this system. R4-M monitors containment atmosphere as required and R4-Al monitors purge exhaust fan discharge to the plant vent.

R4-Al indicates particulate activity, gaseous activity and iodine activity.

The range and calibration sources for these monitors are discusned in detail in Section ll.h.2.1.2.

of the actual input rate.The overall accuracy of the readout is 1 10 percent If the activity exceeds the range of the monitors, the sample bomb may be used to take " grab samples" for laboratory analyses.

,B There are three flow indicators in the discharge system. The high capacity displacement type flow indicator (FI-1) has a rance of approximately 100 to 1000 SCFM and an accuracy of 1 2 percent of full scale. The medium capacity displacement type flow indicator (FI-2) has a range of approximately 20 to 200 SCM4 and an accuracy of 12 percent of full scale. The low capacity dis-placement type flow indicator (FI,3) has a range of approximately h to ho SCFM and an accuracy of 1 2 percent of full scale.

.' h B . S . h . 6 System operation After a loss-of-coolant accident, a minimum of 250 hours0.00289 days 0.0694 hours 4.133598e-4 weeks 9.5125e-5 months (more than 10 days) is available before purging of the containment atmosphere is required even under the conservative assumptions of Regulatory Guide 1.7. Portable engine-driven ecmpressor(s) with an air-receiver tank of the type commonly used in construction vill be connected to the leak rate test con. ections outside the intermediate building. Several such compressor (s) with a capacity of 25 CFM or more vould be obtained to assure that a reliable compress.ed air supply could be maintained in the receiver tanks. These types of air compressor (s) are readily available and, in an emergency, can be obtained in sufficient time from anywhere within the United States to permit. ric1d connection to existing piping provided for this purpone. The enntainment monitoring sub-system contairment. vill be used to monitor the activity and hydrogen concentration of the Prior to ecmmencement of purging, the ccmpressor(s) vill be used to raise and maintain the reactor building pressure to approximately + psig 2 l G

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'(during the entirc. purging period) The operator vi)) monitor vind speed nnd direction in the control room and direct control of the purge rate in accordance with a specific purge plan. The makeup sub-system vill be operated as necessary #

to maintain adequate reactor building pressure. Compressor (s) in sufficient '

number and capacity are available for rental at numerous locations within 100 miles cf the site.

This type of equipment has been previously rented from the followinC companies for construction and maintenence.

1. Air Component & Equipment, St. Petersburg, Florida

2. Compretsed Air Products, Tampa, Florida 3 Hert: Rental Equipment, Tampa, Florida

.Additicnally, Florida Fover Corporation owns and operates within its operational divisions sufficient available compressor capacity.

Conventionally these compressors are engine or electric motor driven equipment.

Sufficient numbers of equipment units are available to provide backup alternate c:pacity for reliable operation.

IhB.6 INTERMITTEMT FUBG1!!G

-1hB.6.1 INTERMITTENT PURGING CONCEPT.

Purging to control. post-accident containment building hydrogen concentratiens can be conducted either continuously or intemittently. Intemittent purging is the preferred mode due to the inherent ability to purge selectively, under favorable meteorological conditions (offshore vinds). The banic premise of thed of - gtermittent purge procedure to be employed is to purge for a maximum l -minutes each day, in the presence g o Beginning at midnight,theoperatorvillinitiatea._goffshorevinds. minute purge as soon as sustained offshore winds are observed. '#' 77 . i '. r 'd r. , th , -

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If.no offshore vinds are detected on a given day, there vill be no purce on that day. The purge rate for a given day vill be detemined by the observed rate of

-increase in the hydrogen concentration in the containment building, and vill be datemined such that as much hydrogen vill be released asds generated that day.

l Tha required purge rate for intemittent purging vill be ~ times the required purge rate for continuous purging. Table lLB-6.1 presents the required contin-uous purge rate to stabili:e containment building hydrogen concentrations, as a function of time, for the LOCA and MHA.

Analysis of on-site meteorolegical data collected during calendar year 1972 indi-cates-that there vere h9 days out of a total of 366 in which no offshore vinds vare recorded. Thi; total includes 3 days in which no data was recorded.

The annlysis of the doses resulting from intermittent purcing in bnned on the radiologien1' impact produer*<1 by the firnt 60 purcen. An dincunned beltu, done o.nnlysis resulto nre obtained first for the initial 30 purges, during which most of the radiciodine either decays or is released. These results are then cxtended by extrapolation to include the first 60 purges. The 197;' meteorolo-gical data indicates that the createst time _ span required to includo 60 dnys in which offshore vinds were observed is 73 days. Thus, intermit tent purging is initiated 13 days (312 hours0.00361 days 0.0867 hours 5.15873e-4 weeks 1.18716e-4 months ) in advance of the required initiatien time lhE-20 Am. 38 (3-25-Th) h

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Potential dosec due-to purges on days where n=? are connidered um11r,1ble. As

' the everaga offshora vind spsd is about 6.9 miles per hour, an offshore vind durs. tion of 1.25 hours2.893519e-4 days 0.00694 hours 4.133598e-5 weeks 9.5125e-6 months (n=2) indicates a mean transport distance, for the midpoint of the plume - given a direct reversal .of almost 19 miles to the LPZ radius. . This transport distance is almost h times the LPZ radius, used in evaluatin6 doses where-n=1. Thus, there were 20 da/s in the year 1972 where, if an intermittent purge had been executed, the resultant doses at the LPZ radius would be considered non-negligible under the above assumptions. These are the 20 days where the value of the parameter n was determined to be equal to one.

The potential doses at the LPZ distance due to intermittent purges on days where n=1 have been conservatively evaluated utilizing the following' assumptions:

12 0 1). The entire -99 minute purge is assumed to be released into the l

following onehore vind characterized by the actual recorded vind speed, direction, and stability class.

2). The plume center-line X/Q at the LPZ distance (calculated using the recorded vind speed, direction, and stability class of the following onshore vind) is utilized to calculate doses.*

3). Adult thyroid I-131 inhalation deses are calcula maximum 8houraveragebreathingrate3.h7x10gedusingthe m3/ sec.

h). External whole P dy doses are caleJated using the semi-infinite sphere model and are based upon the total average beta and gamma energy released per disintegration.

Table lhB-6.3 presents the pertinent meteorological data and the calculated center-line of the plume X/Q values for each of the 20 days of 1972 where t ." n=1 and the folleving onshore vind is not out of the southeast. The activity estimated to be released in each of the first 30 purges, for both the LOCA and !GA, is presented in Table lhP-6.h.

In order to further illustrate the calculational procedure utilized in this analysis, assume that it was necessary to initiate intermittent purging (following a LOCA) on the h0th day of 1972. Examinatien of the metecrological data indicates that radiological impact (n=1) would result from the fifth, eighth, and seventeenth purges. This is because the parameter n was determined to be equal to one on days h5, h8, and 65 of the year 1972.** The doses due to the fifth purge vould be evaluated using the value of X/Q calculated for day h5, (as in Table lhB.6-3) and the activity releases appropriate for the fifth purge (asinTablelhB.6-4) The same evaluation is then performed for the eighth and seventeeth purges. If the doses occur in the same onshore sector, they are summed, and the dose totals due to the first 30 purges are then ecmputed for each onshore sector. The dose totals by sector are then compared and the maxi-mum doses (thyroid and whole body) at the LPZ radius due to the first 30 purges, assuming intermittent purge initiation on day 40, are obtained. The above pro-cedure was repeated for each day of the year 1972, for both the LOCA and MHA, and the results presented in Table lhB-6.2 vere obtained.

The equation used to cciculate the required X/Q valucu is: X/Q = 1/(ne y g ad No offs!---- vinds were observed on days hh , h9, 50, 51, 55, 56, 57, 58 and 63 of the year 1972. Therefore an intermittent purge would not have (w%). been executed on these days.

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'lh B". 6. 3 DOSF. SEtlSITIVITY -

The sensitivity of dose resulting from variations in those parameters considered in Ecction lhB.5.3 vi31 show similar behavior to that demonstrated previously for continucus purcing. Such similarity is to be expected since dose is determined by the activity in the containment building at the time purge starts and the purge rate requirec.

Since neither of these is affected by the purging method used it may be concluded that the dose sensitivity vill be similar.

lhB.6.h INTERMITTFNT FURGING FROCEDURE-The system described under Section 1hB.S.h is operated as previously described except conditions. that an intermittent purge vill be initiated only under certain specified In Appendix lbC, an offshore vind is defined as a vind blowing from any sector frcm north, eastward to the east-southeast cector. Purging of the containment building tc centrol hydrogen, if required, vill be initiated only when the vind is bleving frcm these sectors. Purging, once started .:1 continue for a period of Nminutes. may In the event of an accident which could result in substantial hydrogen generation, the operator vill observe the hydrogen cccumulation rate and vill continually project the time required for the concentration v 3 increase from its present value to 3 5 vol%

When the projected time to reach 3 5 vol% .-comes 312 hours0.00361 days 0.0867 hours 5.15873e-4 weeks 1.18716e-4 months or less, purging is started as soon as the vind direction permits. The cperator vill set the purge rate at l gtimesthedailyrateofchangeofthehydrogenccicentration.

l As the rate of hydrogen generation decreases, the purge flow for any -12+0 minute purg-ing episode is also correspondingly decreased based en the obcerved rate of hydrogen increase in the interval prior to purging.

Information required by the operator to purge according to the procedure outlined above is identified as follows:

1. Containment pressure, psig

2. Centainment temperature, F

3. Purge flow, CFM (actual)

h. Hydrogen concentration, volume percent 5

Elapsed' time frem initiation of previous purge

6. Wind velocity and direction lhB.7 EVALUATION OF INTERMITTENT VS. CONTINUOUS PURGING In Sectionn'1hD.5 and lhB.6 the doses resulting recm continuous and int.cr-mittent purging are evaluated. These results are procent.cd in Table lhli-2.1 where it may easily be observed that doses estimated to result frcm inter-mittent purging are only small fraction of those estimated to result from continuous purging. There is a decided advantage in favor of intermittent purging, in terms of reduced radiological impact to the public.

lhB-2h Am. 28 ( 3-25-74 )

[-

@ 3 0 '

t Table lhB-6.h Activity Releases by Purge for First 30 Intemittent Purges Tice After Accident Activity Releases by Purge. c'uries Required'Intercittent-Purge Until Purge, hrs I-131 Kr-85 Xe-133 Purge Rate, cfc Number IEA LOCA MHA LOCA MHA LOCA MHA LOCA MHA LOCA 3* 6L8 1176 5.10-1 1.71-3 1.40+2 6.38+1 9.77+2 1.98 8%-6 21).2 L 7; . 2 t/8,8 2 672 1200 h.62-1 1.51-3 1.38+2 5.95+1 8.h5+2 1.62 OL'. 0 2 f l.2 LLC. L ill .6 3 696 1224 L.19-1 1.38-3 1. 3 7+2 5 91+1 7.32+2 1.h1 CLL . 0 2i t. 2.L LC . L ill. 4 4 720 12b8 3.49-1 1.26-3 1.2h+2 5.87+1 5.83+2 1.23 777. S l94.4Li!. ' Ill. 6 5 TEL 1272 3.17-1 1.15-3 1.23+2 5.83+1 5.06+2 1.07 7. 7. 0194.4 LL C. L/ / /. /

6 768 1296 2.87-1 1.04-3 1.21+2 5.79+1 h.38+2 9.34-1 777. 5194.4W+Allt. t )

7 792 1320 2.61-1 8.89-h 1.20+2 5.38+1 3.80+2 7.60-1 777.6194.4. L;7. :/Of.4 8 816 134h 2.18-1 8.11-4 1.09+2 5.3h+3 3.03+2 6.62-1 71; . 2176.8 L17. 0/of. 4 9 840 1368 1.98-1 7.39-4 1.08+2 5.31+1 2.63+2 5.77-1 71; . 2: 78.8L 17. !/0 f.4-10 86L 1392 1 79-1 6.74-h 1.07+2 5 27+1 2.28+2 5.03-1 71; . 217&.8 L;7. 5/04.4-11 888 1h16 1.63-1 5.80-h 1.06+2 4.9h+1 1.98+2 4.13-1 71;.2178.8 ;3;.5 9 8.1-12 912 1h40 1.36-1 5.29-4 9.59+1 h.91+1 1.58+2 3.60-1 e n -6164 8 :33. C 98.4 13 936 1h6h 1.24-1 h.83-4 9 50+1 4.88+1 1.37+2 3.1h-1 C; . ld>4.8 ,,_,.C 9 8 4' e lh 960 1488 1.12-1 4.ho-b 9.40+1 h.85+1 1.19+2 2.73-1 C;7. C f 64'.8;;;. : 98 4 5 15 98L 1512 1.02-1 3.77-4 9.31+1 h.53+1 1.03+2 2.2h-1 G;7. C lG4.8 7C, . 92.4-16 1008 1536 8.59-2 3.bh-h 8.5h+1 h.50+1 8.31+1 1.95-1 C;;.:#52 47:;.: 92. 4 17 1032 1560 T.81-2 3.1h-h 8.h7+1 h.48+1 7.22+1 1.70-1 60:.:152.4769-6 92.4-18 1056 1584 7.11-2 2.87-4 8.39+1 4.45+1 6.27+1 1.h8-1 CC .:'52 47:3.; 92. 4 19 108; 1608 6.46-2 2.h8-4 8.31+1 h 20+1 5.L5+1 1.23-1 4 fe% /52.1;;; . '. 87.6 20 110L 1632 5.47-2 2.27-4 7.66+1 h.16+1 h.Lo+1 1.07-1 :::. LI4I. 6 ;L. ; 87.4 21 1125 1656 h.97-2 2.07-h 7.59+1 h.16+1 3.83+1 9 35-2 964A/11 6;%. '. 87.6 22 1152 1680 h.53-2 1.89 h 7.53+1 h.13+1 3.33+1 8.15-2 9 9 /4/.4;L.'. 87 's '

23 1176 170h h.12-2 1.63-h 7.01+1 3.89+1 2.89+1 6.72-2 566A/4/. 4;;1. 2 82.v 2h 1200 1728 3.52-2 1.h9-h 6.96+1 3.87+1 2.37+1 5.86-2 999-e/33.2 ;;1. 2 82.8 25 122L 1752 3.21-2 1.36 h 6.90+1 3.85+1 2.06+1 5.11-2 ;;:.;t3 3.2;;1.2 82.8 y 26 12L8 1776 2.92-2 1.24-4 6.8b+1 3.83+1 1.79+1 4.46-2 5;; . 3/53.1;;1.2 82.8 27 1272 1800 2.66-2 1.08-h 6.79+1 3.6h+1 1.56+1 3.72-2 999-e/53.1;_:.: 79.2.

g 28 1296 182h 2.42-2 9.89-5 6.73+1 3.62+1 1.35+1 3.25-2 532. 2/ 53.2.;1C. 2 79.2.

_ 29 1320 1848 2.07-2 9 03-5 6.26+1 3.60+1 1.10+1 2.83-2 499-e/24.8;;;. : 79.2.

y 30 13ht 1872 1.88-2 8.25-5 6.21+1 3.58+1 9.61 2.h7-2 W/>.4.8 E+:d 79.2.

N v

The first purge is assumed to occur h9 days after a LOCA and 27 days after an MHA.

O

Percentage 15 20 80 85 C

5 10 30 40 50 60 70 90 95 98%

I I II I I I I I I -I ' I :

THYROlO DOSE PROBABILITY

/ --

/ ,, , y ,, 3 2-

- ,/ / -

/

io

/

10-6 -

/ -

/ :

. : /

e _

4 -

/ -

1

/ -

E o

I

/ ,

10-7

_/

t

/ _

7 p -

6 13 3 1 12 )

7

,,,, 5 to

NumbersIndicate Month _

s*

I I l l I l l 10-8 J.5 4.0 4.5 50 5.5 6.0 6.5 Probability Dose 5 0 THYROID DOSE PROBABILITY CRYSTAL RIVER UNIT 3 2.

ET FIGURE 148 6 *-

(AM. 38 3 25 74)

$4

.- N 1

\

1 De-MHA 10-3 m-

.I ~

5 -

S 5 -

o 10 4

_ LOCA 10-5 f ' ' ' ' ' ' ' ' ' ' ' ' ' '

10-2 10-1 1 Probability Dose Will Exceed 0 '

THYROID DOSE PROBABILITY DISTRIBUTION CRYSTAL RIVER UNIT 3 3-

=-

FIGURE 148-6+

, (AM. 38 3 25 74) g

~_ -

.', 10-2

_ MHA 10-3 ~

E LOCA 8 _

~

s 3

C o .

I'./

10~4

~

10-5 J ' ' ' ' ' '

10-2 10 -3 I Probability Ocse Will Exceed D' WHOLE BODY DOSE PROBABILITY DISTRIBUTION CRYSTAL RIVER UNIT 3 4-ga; FIGURE 148-6+

~

A (AM. 38 3-2$ 74) 4 -7

-e.

'?,' ' '

Thyriod 0ose

^- ile Body Dose

g. .: . .-

l l

E l

. l 3 \

8 22 10-2

_ k

' ' ' ' ' ' ' ' ' ' ' ' l 10-3 g 10 -1 10-2 Probability Dose will Exceed O' DOSE PROBABILITY DISTRIBUTION U$lHG REGULATORY GUIDE 1.7 ASSUMP GONS CRYSTAL RIVER UNIT 3g

_ FIGURE 148-6.1-6!

E** '(AM. 38 3-25 74) m

ML19308D675

Text

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