ML20149F385

Proposed Tech Specs,Revising Surveillance Requirement 4.7.7.e.3 to Allow Up to 1000 Cubic Feet/Minute Intake of Fresh Air During Operation of Control Room Emergency Ventilation Sys

ML20149F385
Person / Time
Site:	Sequoyah
Issue date:	01/11/1988
From:	TENNESSEE VALLEY AUTHORITY
To:
Shared Package
ML20149F372	List: ML20149F368 ML20149F385
References
TAC-R00254, TAC-R00255, TAC-R254, TAC-R255, NUDOCS 8801140226
Download: ML20149F385 (18)

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ENCLOSURE 1 PROPOSED TECHNICAL-SPECIFICATION CHANGE SEQUOYAH NUCLEAR PLANT UNITS 1 AND 2 00CKET NOS. 50-327 AND 50-328 (TVA-SQN-TS-87-47)

LIST OF AFFECTED PAGES Unit 1 3/4 7-18 Unit 2 l 3/4 7-18 i

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8801140226 880111 PDR- ADOCK 05000327 P

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1 PLANT SYSTEMS SURVEILLANCE R:0VIREMENTS (Continued)

1. Verifying that the cleanup system satisfies the in place testing acceptance criteria and uses the test procedures of Regulatory Positions C. 5. a. C.5.c and C. S. d of Regulatory Guide 1. 52, Revision 2, March 1978 (except for the provisions of ANSI N510 Sections 8 and 9), and the system flow rate is 4000 cfm : 10%.

2. Verifying within 31 days after removal that a laboratory analysis of a representative carbon sar.ple obtained in accordance with Regulatory Position C.6.b of Regulatory Guide 1.52, Revision 2, March 1978, meets the laboratory testing criteria of Regulatory Position C.6.a of Regulatory Guide 1.52, Revision 2, March 1978.

3. Verifying a system flow rate of 4000 cfm + 10% during system operation wnen tested in accordance with INSI N510-1975,

d. Af ter every 720 hours0.00833 days <br />0.2 hours <br />0.00119 weeks <br />2.7396e-4 months <br /> of charcoal adsorter operation by verifying within 31 cays af ter removal that a laceratory analysis of representa-tive carcon sample obtained in accordance with Regulatory Position C.6.b of Regulatory Guide 1.52, Revision 2, Maren 1978, meets the laboratory testing criteria of Regulatory Position C.6.a of Regulatory Guide 1.52, Revision 2, March 1978,

e. At least once per 18 months by:

1. Verifying that the pressure drop across the combined HEPA filters anc cnarcoal aosorber banks is less than 6 inches Water Gauge while operating the system at a flow rate of 4000 cfm 104

2. Verifying that on a safety injection signal or a high radiation signal from the air intake stream, the system automatically diverts its inlet flow through the HEPA filters and charcoal adsorcer banks.

3. Verifying that the system maintains the control room at a positive pressure of greater than or eoual to 1/8 inch Water Gauge relative to the outside atmospnere at a system flow rate of 4000 cfm +~ 10% (.'~0^ cfm recirculation and '00 cfm fresh air).

>,3 000 S mCO

f. After each comolete or partial replacement of a HEPA filter bank by '

verifying that the HEPA filter banks remove greater than or equal to 99.95% of the DOP wnen they are tested in-clace in accordance with l ANSI N510-1975 wnile cperating the syste at a flow rate of 4000 cfm : 10%.

g. After each complete or cartial replacerent of a charcoal adsorber tank Dy verifying that tne cnarcoal acsor0ers remove greater than or eoual to 99.95% of a halogenated hydrocar00n ref rigerant test gas when they are tested in place in accorcance with ANSI N510-1975 wnile operating the system at a flow rate of 4000 cfm : 10%.

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PLANT SYSTEus SURVEILLANCE RE0VIREMENTS (Continuedi

1. Verifying that tne cleanup system satisfies the in place testing acceptance criteria and uses the test procedures of Regulatory

. Positions C.S.a, C.5.c and C.S.d of Regulatory Guide 1.52, Revision 2, March 1978 (except for the provisions of ANSI N510 Sections 8 and 9), and the system flow rate is 4000 cfm 3 10%.

2. Verifying, within 31 days af ter removal, that a laboratory analysis of a representative carbon sample obtained in accordance with Regulatory Position C.6.b of Regulatory Guide 1.52, Revision 2, March 1978, meets the laboratory testing criteria of Regulatory Position C.6.a of Regulatory Guide 1.52, Revision 2, March 1978. .

3. Verifying a system flow rate of 4000 cfm + 10% during system operation when tested in accordance with ANSI N510-1975.

d. After every 720 hours0.00833 days <br />0.2 hours <br />0.00119 weeks <br />2.7396e-4 months <br /> of charcoal adsorber operation by verifying within 31 days after removal, that a laboratory analysis of a represen-tative carbon sample obtained in accordance with Regulatory Position C.6.b of Regulatory Guide 1.52, Revision 2, March 1978, meets the laboratory testing criteria of Regulatory Position C.6.a of Regulatory Guide 1.52, Revision 2, March 1978.

e. At least once per 18 months by:

1. Verifying that the pressure drop across the combined HEPA

• filters and charcoal adsorber banks is less than 6 inches Water Gauge while operating the system at a flow rate of a000 cf,m i 10%.

2. Verifying that on a safety injection signal or high radiation signal from the air intake stream, the system automatically diverts its inlet flow through the HEPA filters and charcoal aosoroer banks.

3. Verifying that the system maintains the control room at a positive pressure of greater than or equal to 1/8 inch Water Gauge relative to the outside atmosphere at a system flow rate of 4000 cfm : 10% (-9600-cfm recirculation and fefr cfm fresh air).

b3000 Stoco

f. Af ter each complete or partial replacement of a HEPA filter bank by verifying that the HEPA filter banks remove greater than or equal to 99.95% of the 00P when they are tested in place in accordance with ANSI N510-1975 while operating the system at a flow rate of 4000 cfm : 10%.

g. After each complete or partial replacement of a charcoal adsorber bank by verifying that the charcoal adsorbers remove greater than or equal to 99.95% of a halogenated hydrocarbon refrigerant test gas when they are tested in place in accordance with ANSI N510-1975 wnile operating the system at a flow rate of 4000 cfm + 10%.

SEQUOYAH - UNIT 2 3/4 7-18

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l ENCLOSURE 2 PROPOSED TECHNICAL. SPECIFICATION CHANGE SEQUOYAH. NUCLEAR PLANT UNITS 1 AND 2' DOCKET NOS. 50-327 AND 50-328 (TVA-SQN-TS-87-47) -

DESCRIPTION AND JUSTIFICATION FOR THE INCREASE OF THE CONTROL ROOM EMERGENCY VENTILATION SYSTEM FRESH AIR-INTAKE i

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ENCLOSURE 2 Description of Change Tennessee Valley Authority proposes to modify the Sequoyah Nuclear Plant Units 1 and 2 Technical Specifications to revise surveillance requirement (SR) 4.7.7.e.3 to allow up to 1000 cubic feet / minute (cfm) intake of fresh air during operation of the control room emergency ventilation system >

(CREVS).

Reason for Change Ouring the current outage, a significant amount of special testing has been performed on CREVS. This testing identified several deficiencies and previously unidentified system interactions. These findings are documented in Condition Adverse to Quality Reports (CAQRs) SQP871226, SQP871606, and SQP871657. 1 A significant system interaction that was identified directly impacts the control room pressurization surveillance. This interaction existed between the normal control building pressurization fans and CREVS. The flow diagram for these systems is SQN Final Safety Analysis Report (FSAR)

Figure 9.4.1-2. The logic diagram is FSAR Figure 9.4.1-3.

The system design called for the normal control building pressurization fan flow to be decreased from 8200 cfm to approximately 3000 cfm if a control room isolation (CRI) was initiated. The CRI also isolates flow control valves (FCVs) 31A-105A and 31A-106A. This isolation directed the normal pressurization flow to the suction of the electrical board room air handling units. These units in turn supplied outside air to the two lower floors (elevations CEl.) 669.0 and 685.0) of the control building. -

A deficiency in this system that was discovered during the special testing was that the normal pressurization flow was not adequately reduced during a CRI. The failure of a nonsafety related controller for the fan blade pitch caused the inadequate flow reduction. The controller logic is shown on FSAR Figure 9.4.1-3. Because it was nonsafety related, the controller was not routinely calibrated or tested. The resulting high flow from the

normal pressurization fans, and thus from the electrical board room air handling units, resulted in an abnormal pressurization of the lower two elevations of the control building. Normal ieakage around doors and wall penetrations allowed air to pass through the stairwells and into the cable spreading room (El. 706.0). This provided the potential for a pressurization of the cable spreading room and the stairwells that lead to the control room elevation. The pressurization of the cable spreading room and the stairwells would have masked the potential for outleakage from the habitability zone and, if severe enough, would have resulted in unfiltered inleakage into the habitability zone. The potential radiological consequences for unfiltered inleakage are currently being assessed.

As an interim measure, power has been removed from the normal pressurization fans, eliminating the potential for pressurization of the cable spreading room. A permanent design fix is being developed, because the controller involved has a poor performance history in this and other appl i ca tions .

A system interaction that was identified that directly impacts the ability to satisfy SR 4.7.7.e.3 was also identified. This interaction involves the discharge duct of the spreading room supply fan. On a CRI signal, the spreading supply fan stops and flow control operators (FCOs) 31A-17 and 31 A-102 isolate. As can be seen on figure 9.4.1-2, the recirculation suction duct for the control building emergency air cleanup fans tied into the spreading room supply fan duct. In this configuration, operation of CREVS induced a substantial differential pressure across FCOs 31A-17 and 31A-102. This caused a backflow of air from the spreading room, through the blade-type isolation dampers, through the idle spreading room supply fan, and into CREVS. This backflow would serve as additional makeup flow to CREVS, and until the recent testing, was not identified or quantified.

The radiological consequences of this additional makeup flow are minimal, as the air is passed through the CREVS filter banks before reaching the control room. The impacts of increased filtered makeup flow are discussed in detail in the justification section that follows.

To minimize the likelihood of drawing makeup air from the cable spreading room, the CREVS recirculation duct has been disconnected from spreading room supply fan duct, and now draws air from an independent point in the El.732 mechanical equipment room.

As stated above, the main control room has sufficient out leakage such that when CREVS is operated with 200 cfm intake of fresh air, it may not maintain control room pressure at & positive 1/8 inch water gauge, or the rest of El.732 slightly positive, as described in FSAR section 9.4.1. If the control room habitability zone is not maintained at a sufficiently positive pressure, the potential exists for unfiltered contaminated air to 5 l

leak into the control room habitability zone. I Justification for Change Division of Nuclear Engineering (DNE) Calculation SQHAPS3-082 (attachment 1) was performed to determine the effect on operator dose of increasing the ratio of fresh air to recirculated air processed by CREVS.

The methodology for this calculation is consistent with that described in FSAR section 15.5.3. The assumptions used in the calculation are also consistent with other TVA postaccident dose calculations and are listed on page 1 of the ca!culation.

The total calculated operator dose in the control room is composed of three parts. The first part is the dose from activity surrounding the control room habitability zone. This dose is independent of the fresh air flow in CREVS. Additionally, it contributes only to the whole body dose.

The dose from the surrounding activity is 0.07 rem.

The second contributing factor to control room operator dose is the result of traveling to and from the control room during the accident period (30 days). This dose is also independent of the fresh air makeup in CREVS. This dose contributes 0.06 rem whole body dose. 0.1 rem beta dose, and 1.0 rem innalation dose.

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. f The third contributing fact N to the control room operator dose is from the activity inside the control room habitability zone. The activity '

inside the control room is due to the contaminated fresh air that is '

processed by CREVS for pressurization of the control room and a defined amount of unfiltered inleakage.

The calculation shows that the whole body dose to the operator increases l from 1.1 rem to 1.5 rem as the fresh air flow rate increases from 200 cfm to 1000 cfm. This is to be expected, since mcre contaminated air is being  !

processed by CREVS, and ultimately delivered into the centrol room. The i' whole body dose is principally due to the noble gas activity, which is not affected by flitration or absorption. The beta dose, which is also principally due to the noble gas activity, increases from 10.3 rem to '

15.2 rem. The beta dose is essentially the skin dose, and would affect only uncovered parts of the operator's body. Finally, the inhalation dose [

decreases from 13.5 rem to 10.4 rem as the makeup flow increases. This is because of the relative dose contributions of the filtered and unfiltered air entering the control room. From measurements it has been determined l that a pressurized duct carrying unfiltered air to CREVS equipment will leak at a rate of 51 cfm. This is unfiltered leakage into the control ,

room habitability zone. The fresh air makeup flow used to pressurize the '

control room balances the outleakage from the control room; therefore, the i greater the makeup flow rate, the shorter the residence time of the activity in the control room, and the smaller the buildup of activity.

Because the ratio of filtered air to unfiltered inleakage increases as the makeup flow increases, there will be less total activity in the habitability zone, resulting in lower inhalation dose. t In summation, the results of the calculation show that the 30-day  !

postaccident total control room doses are 1.6 rem whole body,15.3 rem - i beta, and 11.4 rem inhalation for a fresh air makeup flowrate of  ;

1000 cfm. These values are well within the 10 CFR 50 Appendix A, .

Criterion 19 limits of 5 rem whole body or its equivalent to any part of '

the body. '

t An alternative to increasing the CREVS makeup flow involves the detection and isolation of leakage paths from the control room habitability zone.  ;

This option is being pursued in parallel to the proposed technical '

specification change. This option requires extensive walkdowns and i saarches to find and seal leaks in the habitability zone. The remaining  :

leakage is considered to be the result of a large number of very small  !

leaks, e.g. the floor penetrations from the main control room to the cable spreading room. It is estimated that the attempts to further reduce the outleakage to 200 cfm have a low probability of success. At a minimum, over 1800 man-hours has already been expended in locating and sealing }

leaks, and the associated testing, in the attempt to meet the current surveillance requirement. Assuming an average cost of $60/ man-hour, over

$108,000 has been spent on the effort to satisfy the current surveillance requirement. This cost is compared to the benefits of reducing the '

additional dose to the operators as a result of increasing the makeup flow. As stated earlier, the calculation has shown that whcle body dose r increases 0.4 rem from the increased makeup flow. Assuming that 50 operators are in the control room to receive the increased dose, and assuming a cost-benefit ratio of $5,000/ man-rem, the value of reducing the  !

0.4 rem additional dose is $100,000. The $5,000/ man-rem is an average j,

DNE cost-benefit ratio when determining the benefits of reducing exposure to site personael. This value is 5 times greater than the $1,000/ man-rem ratio p.ovided in 10 CFR 50 Appendix I. It is the comparison of the

$100,000 benefit compared to over $108,000 in costs that indicates that the small increase in the 30-day postaccident control room dose is acceptable.

The surveillance requirement is revised to allow any makeup flow up to the 1000 cfm limit of the calculation. This is justified. In that 1000 cfm '

makeup flow will not exceed the control room operator dose limits of 10 CFR 50 Appendix A, Criterion 19, but a makeup flow rate less than 1000 cfm will satisfy the pressurization requirement.

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." "TvA 10697 (ONE-0A--86) DNE CALCULATIONS l Title DETERMINE THE MAXIMUM ALLOWABLE FILTERED MAKEUP FLOW, UP l Plant / Unit l_TO 1.000 CFM. INTO THE CONTROL ROCM - _ _ _ _ _

l Seouoyah Nuclear Units 1.& 2 lPreparingOrganization lKEYNOUNS(ConsultRIHSDescriptorsList)

J __0NE/NE8/Aps3 I CONTROL ROOM OPERATOR DOSE FILTERED FLOW STP, FENC00$F. COR00 Branch /ProjectIdentifiers lEachtimethesecalculationsareissued,preparersmustensurethatthe loriginal (RO) RIMS accession nunter it. filled in.

SQNAP53-492 lRev (for RIM 5' use) RIMS ACCESSION __ NUMBER R0 ! !B45 '871231 23 F Applicable Design Document (s) l l l lR l I.

N/A R

SAR 5ection(s) l UNIO System (s) l l l 15.5.3 iN/A I R l l Revislen 0 R1 l R2 i R3 ISafety-relatedt Yes (x) No ( )

ECN No. (or Indicate Not Applicable) '

l Statement of Problem W/A l Prepar d l Cetemination of the largest allowable a I ,_. l 1

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l I filtered trakeup flow, up to 1,000 cfm, Chec l l l l Into the control recrn without exceeding N l  ! l l10CFR50,AppandixA,GeneralDesign Review,,p jjf l l Celterlon 19, for maximum contro) room

1. 1. JW I I operator dose. ,

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l%.31 97 -  ! l USE FORM l List all pages added l l l l TVA10534lbythisrevision I l I l IF MORE List all pages deleted l l l l

$ PACE by this revision _l l l REQUIRED List all pages changed l l l by this revision i l l lA85 TRACT (These calculations contain an unverified assumption (s) that rnust be sertfled later, Yes ( ) No (x))

l l During an accident, the control roco is pressurized to pruvent unfiltered air from seeping into the control room.

l The current filternri makaup ficw into the control room is 200 cfm. However, it has bem found that this flow is lnotsufficienttokeepthecontrolroomatapositivepressure, As Tresult7th's filtered flow must be increased.

The purpose of this calculation is to detemitie what the maximum allowable flitered flow can be without exceeding

, the control room,.opeta, tor dose given in 10CFR50, accendix A. General Design Criterion 19 of 5 rem whole body or it equivalent to any part of the body, l The calculation was perforred by taking the COR00 run ENVCORD used in SQNAPS3-067, R0 and changing tha filtered l ficw from 200 cfm to 300, 500, 800, and 1,000 cfm.

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I l Continued on page 2.

( ) Microfilm and store calculations in RIMS Lervice Center Microfilm and destroy. ()

(x) Microfilm.aed return calculations tot 5. Taylor address: W10 0222 C-K cc: RIMS, SL 26 C-K ONE4-1916Q

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$QNAP53-062

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the resul'.Ing doses for each flow are shown below: ~

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200 300 500 800 1,000 2fm cfm cfm cfm cfm Dose from activity inside

'"confriilroom (Rem)

..Gama 1.1 1.2 1.3 . l.5 1.5 -

Beta 10.3 11.5 13.1 14.5 15.2 1.ihalation 13.5 _ . 12.1, , , p.9, ,,,,_10.4 10.4 ,, , , , ,

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Total dose from ~~'

all sources '

(Rem)

GamM 1.2 1.3 1.5 1.6 1.6 Beta 10.4 11.6 13.2 14.6 15.3 Inhalation 14.4 13.0 11.9 11.4 11.4 The filtered makeup flow into the contr01 room may be increased to the assumed maximum of 1,000 cfm without exceeding the control room operator dose limits.

The'ccreputer output is stored in RAO-179.

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', NRP-3.1 Attachment 6 C .

page 1 of 1 CALCUI.ATION DESIGN VERIFICATION (INDEPENDENT REVIEW) FORM Sd4 APS 3 - ott o

, Calculation No. Revision ,

Method of design verification (ladopendent review) used (check raethod used): ,

1. Design Review V

2. Alternate Calculation

3. Qualification Test Justification (explain below):

Method 1: In the desip review m6thod, justify the technical adequacy of the calculation and explain how the adequacy was verified (calculation is similar to another, based on accepted hr.ndbook methods, appropriate sensitivity studies included for confit.ence, etc.).

Method 2: In the alternate calculation method, identify the pages where the alternate calculation has been included in the calculation package and explain why this method is adequate. l j

C Method 3: In the qualification test method, identify the QA documented i

source (s) where testin5 adequately demonstrates the adequacy of this

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TENNESSEE VALLEY AUTHORITY S..n in 4 SUBJECT DETERMINE TME MAXIMUM ALLOWAGLE FILTERED _, PROJECT GON units i t<0 MAMEUP FLOW. UP T0.1.000 CFM. INTO THE CONTROL ROOM SONAPS3-080 _ FU)

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@*l8 is/D/f7 Introduction During an accioent. the contral room is pressuri:ed to prevent unfiltered air from seeping into the control room.

The current filtered makeuo flow into the control room is ,

200 cfm with 3.800* cfm recirculation flew (reference 7).

However. it has been found that this flow is not sufficient to keec the control room at a positive pressure. As a result. the filtered flow must be increased. The purpose of this calculation is to determine what the manimum allowable

' filtered flow can be without exceeding the contrel room operator dose given in 10CFR30. Appendix A. General Design Criterion 19 of 5 rem whole body or its equivalont to any part of the body.

Assumptions 1.) The assumptions for the control room ocorator dose analysis in SONAPSO-067 RO are the same for this calculat an, (the annumptions used f rom SCNAPSO-067 R0 are listed below).

The control room operater dose analysis incorporates the activity releases uund in determining the offsite doses. Other .

assumptions employed are those in the operator done analysis given in the CCRCD validation and User's Manual with the following modifications:

1. Unfiltored air leaks into the control ecom habitability :ene at a rato of 51.0 cfm (see attachment 16 of SCLAPSO-067 RC).

2. The centrol room ventilaticn system iodino filter efficiencies derived from Reg.

Guides 1.52 Rev 2 and 1.140 Rev. 1 (Ref.

OS of SONAFSO-67 RO) are 95 % fer the first case and 70 % for the second cass.

2.) The $animum filtered flow that would be required to crusuuri:o the control room is ossumed to be no greator than 1.000 efm.

"The original analysis (SONAPSO-067 RO) inadvertantly  !

used a valuu of 4.000 cFm for the racire ficw. However, as I can be seen in thi s analysi s the di:e of thic arrar, from l 4.000 to 0.000 cfm. deos not recult in a significant change in the final dese.

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TENNESSEE VALLEY AUTHORITY S-ut Ow 4 SUBJECT DETERMINE THE MAXIMUM ALLOWAGLE FILTERED PROJECY 30tl unitz 1 R,0 MAKEUP FLOW. UP TO 1.000 CFM. INTO THE_ CONTROL ROCM soNAps;-0cm " po

""*'""fLju,,} **'* J2/3/)y unanse es g ears 4

Precedure The first step was to rerun the GTP model CNVLuCA with the corrections outlined in SCNAPSO-067 cr pages 18 snd 19. The source terms in ENVLOCA were developed usir q the methodelcoy found in TID-14844 fer 1,000 offecti"e full power days. The activities produced by STP for c=moc1ents 1 and li were then ,

placed into FENCDOSE to be summed. The purge air releases given en page 28 of SONAPS0-067 wers then added tc- the first time step of the FENCDOSE output, tne summation of the two components.

These activities were then substitutsd into CORCD input ENVCCRD from SONAPS3-Ot:7.

Five COROD runs were made for various filtered fic.ws along with the corresponding reduction in thu recircula'.icn flow.

No other part of inout was changed between the rv nn. The five filtered flown. the associated recirculatior flows, and their resoective job-names ara:

Filtered Flcw Recirculation Jcb Name cfm cfm 200, Design Soec. O,000 C200RD00 300 0.T00 ECCORD00 500 0,C00 ECCCRD50 G00 3.200 E CCROSO 1.000 3.000 E200RD1T e

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TENNESSEE VALLEY AUTHORITY S...,  ; , 4 8UBJECT DETEPMINE THE MAXIMUM ALLOWASLE FILTERED PROJECT GON nits 1* 0 MAKEUP FLOW. UP TO 1.000 CPM, INTO THE CCNTROL ROOM SONAFST-082 RO satw sewateo sv g j g/3f/p cass= e ev pg gjg,g sets l

Results I The ensults of the five CCROD run are givan in Tabla 1.

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Tr.ble 1: CCRCD Results for Varicus Filteied Flow '

200 000 000 000 1,000 cfm cfm cfm efm cfm Lone from activity inside control r=om (Rom)

Gemma 1.1' 1. O ' 1.!' 1.!' 1.5' ,

Bete 10.0 ' 11.!' 10.1' 14.!' 15.O '

Inhalatien 10,5 ' 12.1 ' 10.?' 10. V

10. P Total doso from all sourcan (Rem)

Gamma 1.0' 1. 0 - 1. '

1. 5 ' .1. 6 '

Esta 10.4' 11.4/ 10.2' 14.6' 15.0/

Inhalation 14.4' 10.0 / 11.?' 11. V 11.4 '

s

p. .

4 .

TENNESSki. VALLEY AUTHORITY S ur 4w 4 SUBJECT DETERMIME THE MAXIMUM ALLOWADLE FILTERED PROJECT GCN units 100 MAKEUP FLOW. UP TO 1.000 CFM. INTO THE CONTROL ROOM SONAPG7-022

.~,.* W,.s ~' n(sk * ' ~ '

ww3 ~'

i Wro Vi RO Conclusion The filtered makaum flow into the centecl reem may be increased to the assumed manimum of 1.000 cfm without exceeding the control recm coeratcr dona limi ts of 5 rem gamma, 00 rem beta. and 30 rem inhalation cut 11ned in ,

10CFR50, Appendix A, General Design Critarien.

References

1. SONAF50-067 RC "Offsite anc Centec; Rcem Ocerater Deses Due to 'a NHA LOCA with c. Manimum Alloweb1k Annulus Inicskage" Rims 9 CD45 370G:5 0 63.

2.

TI-RP3 109 R1 "Verification of Ccmouter Code CTF" Rims #

CNEB 841004 055].

O. TI-039-3 R1 "Ccmmuter Program FENCDO3E" Rims M CD45 B70514 005].

4 GENNALO-009 R1 "Qualification of Ccmouter Ccdn COROD" Rims # CB45 87000 205].

5 GENAPSO-018 RO "NE3 Library Verification" Rims # CE45 670504 2363.

. 6. 10CFR50, Accendin A. General Design Criterien 19, 19G7.

7. TVA DWNG 47WE66-4 R01.

S. TID-14944 by J. J.

DiNunne. "Calculation of Distanca Factors fcr Power and Test Rescter Sites," Atomic Ensegy Ccomi ssion. Washingten. D.C.. March 1960.

9. Ccmputar Output used in this cr1culation ENYLCCA - 1076. 27 Occ. 1907 STP run l ENVFENC1 -

?19. 24 Dec. 1707 PENCDOOC run E: CORD 20,- 1550. 30 Dec. 1757 CCRCD cun for 200 cfm

- 1 E CORD 00 - 1551. 30 Dec. 1957. CoRCD run for 000 cfm l ECCCRD50 - d1550. 00 Dec. 1?37. COPCD eun icr 500 cfm  !

ECCCRDGQ - 1' !0. 00 Dec. 1927. CCROD rur. for 300 cfm ECCCRDIT - 1554 00 Dec. 1937. CCROD run icr 1,000 efm

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m W 8-A>,4- W e4. J.-M - AE 4- p h - p .JB44 5-. -

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Ig

. ENCLOSURE 3 PROPOSED TECHNICAL SPECIFICATION CHANGES SEQUOYAH~ NUCLEAR PLANT UNITS-I AND 2 DOCKET NOS, 50-327 AND 50-328 (TVA-SQN-TS-87-47) ,

DETERMINATION OF NO SIGNIFICANT HAZARDS CONSIDERATIONS j

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