ML20141H117

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Proposed Tech Specs,Replacing Pages 147,156 Through 161,168 & 279 of Util TS W/Corrected Pages
ML20141H117
Person / Time
Site: Vermont Yankee Entergy icon.png
Issue date: 07/11/1997
From:
VERMONT YANKEE NUCLEAR POWER CORP.
To:
Shared Package
ML20141H113 List:
References
NUDOCS 9707220015
Download: ML20141H117 (29)
v • d • e


Text

-

. o Vermont Yankee Proposed Change No.190 Marked-up Technical Specification pages i

)

i I

9707220015 970711 DR ADOCK 05000271 PDR l

._ . _ _ . . ._ . _. _._ __ . ._.... ._ ~ _ _ . . _ . ~ . . > _ . . . . .__.__.m__.

c- . ,

VYNPS 3.7 LIMITING CONDITIONS FOR 4.7 SURVEILLANCE REQUIREMENTS OPERATION -

e. Minimum Water -

Y 1 "' ~

I 4 68,"000 cubic feet %P%

g dgNWM l j

f. Maximum Water "*3#
  • CD" 2

Volume -

l 70,000 cubic feet j 2. Primary containment 2. The primary containment i integrity shall be integrity shall be maintained at all times demonstrated as required when the reactor is .by pe ix to c i critical or when the t5. e pr ma

' reactor water nt nme s 1 et temperature is above th con i t j 212*F and fuel is in the a opt ce qu eme s a reactor vessel except et rth n-t t j

' while performing low '

ap ndi

{ power physics tests at

! atmospheric pressure at . ene ati sa 1

power levels not to se s1 ted 'n 1 exceed 5 Hw(t). T le .7.1 hal 1 kt ted t

3. eve pri ry 44 sig a).

nta en is r ire , .

j. he otal rima . e tes s s 11 '

co ai nt 1 kage ate be rfo d t

! 11 ot ex eed is at nv ve eight orce pe

.8 at .in /

{; da (L ta oss e ab 4. .2. /

44 p.) g (P ) .

i 3. Mior o v' la ng he

, 4. Whenever primary / int rit of sy em i, containment is required, o side he ri ry 8

tyre le age rom ny .e nta , w ich a 4 sol ion lv sha con et to y lve not exce t

5

' um llo ble rce of (hnk) li ed n e ola on le lv

.7. ,

eak te ,) e pe j u in the pen g acc ent res re ,) / s 11 ve e to s an#/the leakage from any erf If he one main steam line o ing ann be isolation valve shall i lat fr t not exceed 15.5 scf/hr ont nme by two at 44 psig (P,). iso ati va es ic ttea opt ce rit ia and J v -

(10 rt ), bl k T4

  • 9"fM*^ ", (( .n .n ns le on e is c.oof dare md op ing f prWaN **^**\^#**

)

f\

.na de...wv =4 ed c.w+ **Mc Va%

k- a \*

The leakage from any one main steam line

,,go w e.mt va\we oc MaJ @ ~3*' isolation valve shall not exceed 11.5 scf/hr at 24 psig (Pt). Repair and retest shall be conducted to insure compliance.

Amendment No.~50 147 l

j<, , .

I VVNPS 3.7 LIMITING CONDITIONS FOR 4.7 OPERATION' SURVEILLANCE REQUIREMENTS l 5. Core spray and LPCI pump 5.

lower compartment door The core spray and LPCI l lower compartment openings shall be closed openings shall be at all times except checked closed daily, during passage or when reactor coolant temperature is less than 2120F.

D. Primarv Containment D.

Isolation Valves E h er containment Agg h on Valves

1. During reactor power 1.

operating condit;.ons al. Surveillance of the c.****+ isolation valves '

primary containment lih >raFle/4. 7. 21 and all listed isolation valves should be performed as follows:

instrument line flow check valves shall be a. The operable operable exc c as specified in isolation valves that are power Specification 3.7.D.2. operated and automatically initiated shall be tested for lithcA in """***Ci' P g 7p initiation and the closure times specified in Table 4.7.2 at least once per operating cycle.

  • b. Operability testing of the primary containment isolation valves shall be performed in accordance with Specification 4.6.E.
c. At least once per quarter, with the reactor power less than 75 percent of rated, trip all main steam isolation valves (one at a time) and verify closure time.
d. At least twice per week, the main

, steam line isolation valves shall be exercised by partial closure and subsequent reopening.

Amendment No. W, M, Me, m,147 156

m. _ _- - - - - - _ - . _

. . .- . .. . - . . - - .. --. . .- - - . ~ . .. .- . . -

< s VYNPS

].

3.7 LIMITING CONDITIONS FOR 4.7 SURVEILLANCE REQUIREMENTS OPERATION 2.

pc.nwn me.c+

In the event any 2. Whenever af isolat%9n isolation valve specified in <T4bl4 f.7 /2 I valve listed inl&<742Lis inoperable, the positfoW

becomes inoperable, T( of at least one other

, reactor power operation valve in each line may continue provided at having an inoperable least one valve in each valve shall be logged line having an daily.

inoperable valve is in the mode corresponding to the isolated

condition.

4he. PcLRTP

3. If Specifications 3.7.D.1 and 3.7.D.2 cannot be met, an orderly shutdown shall

' be initiated and the reactor shall be in the

cold shutdown condition within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />.

4 f

I 4

s 4

1 157

VYNPS PEN RATION, AND SE S SUBJE TO TYP B TESTI

/

1 Pen ration umber D

/ /

Id tificat on in Steam ine A, N er of P etration/

4

/-7A, X-9A, X-1 Feedwat HPCI Line A B am Li 2

1 12 Shu own Co ing Sup y 1 X-13A, R Retur to Reac or 2 X-14 Supply o Reacto Water C ennup X- A, B Core pray to eactor 2 i

-1 E pment A cess Hat 1 X-3 rywell ad Flang 1 X-4 Drywel Head Ac ss Hatch l X- CRD emoval H ch 1

-A, H S ar Lug cess Cov s 8 X-202A, & J, acuum R ief Acce s Covers 10 X-213 , B Torus rains X- OA, B To Manways 2 1

( Lun+1onmn y rut) 158

s.

VYNPS i TABLE'4.7.

PRIMARY CotRAINMEt@ ISOLA, ION VALVES

- VALV[S SUBdECT 'Pd TYB[ LBd(AGEMSTS

' f I f / / /

Number of Power Operated Valves Maximum

. Action on Operating Normal Initiating r p Valve Identification Inboard Outboard Time (sec) Positiert Signal 1 Main Steam Line Isolation (2-80A, D& 4- 4 5 (Note 2) Open GC 2-86A, D) l 1 Main Steam Line Drain (2-74, 2-77) 1 1 35 Closed SC 1 Recirculation Loop Sample Line (2-39, 2-40) 1 1 5 Closed SC 2

2 RHR Discharge to Radwaste (10-57, 10-66)

Drywell Floor Drain (20-82 20-83) 2 2

25 20 Closed (c Open GC 2 Drywell Equipment Drain (20-94, 20-95) 2 20 Open GC 3 Drywell Air Purge Inlet (16-19-9) 1 10 Closed SC 3 Drywell Air Purge Inlet (16-19-8) 1 10 g 3 Drywell Purge & Vent Outlet (16-19-7A) 1 10 Closed

  • SC 3 Drywell Purge & Vent Outlet Bypass 1 10 Closed SC (16-19-6A) 3 Drywell & Suppression Chamber Main Exhaust 1 10 Closed
  • SC (16-19-7) 3 Suppression Chamber Purge supply (16-19-10) 1 10 Closed SC 3 Suppression Chamber Purge & Vent Outlet 1 10 Closed SC (16-19-7B)  !

3 Suppression Chamber Purge & Vent Outlet 1 10 Open GC .

Bypssa (16-19-6B)  !

i

  • Valves 16-19-7 and 16 .3-7A shall have stops' installed to limit valve opening to 500 or less. i Amendment No. 54, 91, 131 159 I l

s l

VYNPS TABLE 4.7. '

(Cont'd)

PRIMARY CONTAINMENT ISOLATION VALVES

/ALVIS

/ /SUIIJEC[TO

/ / TME / C lbKAGF/

/ / TESTS / >

FMmber of Power Operated Valves Maximum Action on Isolation Operating Normal Initiating Group (1) Valve Identification Inboard out boa r'1 Time (sec) Signal Position 3 Exhaust to Standby Gas Treatment System 1 10 Open GC (16-19-6) 3 containment. Purge Supply (16-19-23) 1 10 Open

@ 3C-containment keup '10 20 .0, 3

16-20-22A r

? -2 )

hI NA Closed SC

\ ~-> h t9'Y 5 Reactor Cleanup System (12-15, 12-18) 1 1 25 Open GC l 6 HPCI (23-15, 23-16) 1 1 55 Open GC 6 RCIC (13-15, 13-16) 1 1 20 Open Primary / Secondary Vacuum Relief (16-19-11A, GC 2 NA Closed SC 16-19-11B)

Primary / Secondary Vacuum Relief (16-19-12A, 2 NA Closed Process.

  • 16-19-12B) l 3 Containment Air Sampling (VG 23, VG 26, 4 5 Open GC 109-76A&B)

Feedwater Check Valves (V2-27A, -96A. -28A, NA Open Process

-28B) 4 JJ 7 v v N 7 3 COnhwed Ake.up supply 2. I ope.a Gc.

A -

A A  !

Amenilment No. 58, 61, 74, 91 122 160

VYNPS TABLE 4.7.

( cont'd)

PRIMARY COtFTAINMENT ISOLATION VALVES V M VES NOT /SU6 JECT M TYP/ C LEAKAGE 'fkSTS/

/ ( f f / f /

Number of Power Operated Valves Maximum

. Action on ro p Inboard Outboard Operating- Normal Initiating

-Valve Identification Time (sec) position Sional 2 RHR Return to Suppression Pool (10-39A, B) 2 70 Closed SC 2 RHR Return to Suppression Pool (10-34A, B) 2 120 Closed SC 2 RHR Drywell Spray (10-26A, B& 10-31A, B) 4 70 Closed SC 2 RHR Suppression Chamber Spray (10-38A, B) 2 45 Closed SC 3 Conts in nent Air Compressor Suction (72-38A, 2 20 Open GC B) 4 RHR Shutdown Cooling Supply (10-18, 10-17) 1 1 28 Closed Standby Liquid Control Check Valves (11-16, SC 1 1 NA Closed Proc.

11-17)

Hydrogen Monitoring (109-75 A, 1-4; 10 NA NA NA 109-75 B-D, 1-2)

Sampling Valves - Inlet

  • Hydrogen Monitoring (VG-24, 25, 33, 34) 4 NA NA NA These each line is required to be operable.

valves are remote manual sampling valves which do not receive an isolation signal. Only one valve in Amendment tio . Se, 61, H5, 122 161

.. -- . . - . . . ~ .- _ - _ . - _ ~ _ _ - - . _ . - . - . - . .

VYNPS BASES: 4.7'(Cont'd)

The maximum allowable test leak rate at the peak accident pressure of 44 psig (La) is C.80 weight t per day. The maximum allowable test leak rate at the retest pressure of 24 psig (Lt) has been

. conservatively determined to be 0.59. weight percent per day. This value will be verified to be conservative by actual primary containment leak rate measurements'at both 44 psig and 24 psig upon completion of the containment structure.

[To low a rgin or sible eakag deter orati betw n to in rval the imum llowa e ope ation leak ate ( m), ich /

w' 1 be t to emain n the norma test chedul , is 0 75 Lt [

As most leakage and deterioration of integrity is expected to occur through penetrations, especially those with resilient seals, a periodic leak rate test program of such penetration is conducted at the peak accident pressure of 44 psig to insure not only that the leakage remains acceptably low but also that the sealing materials can withstand the accident pressure. g C.a4*wnsM- Thefeakfatefesting l rogram is based on M g61geFf W for I

App w[J development of leak rate testing and surveillance scheduAes to reactor containment vessels.

Surveillance of the suppression Chamber-Reactor Building vacuum breakers consists of operability checks and leakage tests (conducted as part of the containment leak-tightness tests). These vacuum breakers are normally in the closed position and open only during tests or an accident condition. Operability testing is performed in conjunction with Specification 4.6.E. Inspections and calibrations are performed during the refueling outages: this frequency being based on equipment quality, experience, and engineering judgment.

The ten (10) drywell-suppression vacuum relief valves are designed to open to the full open= position (the position that curtain area is equivalent to valve bore) with a force equivalent to a 0.5 psi differential acting on the suppression chamber face of the valve disk. This opening specification assures that the design limit of 2.0 paid between the drywell and external environment is not exceeded. Once each refueling outage each valve is tested to assure that it will open fully in response to a force less than that specified. Also it is inspected to assure that it closes freely and-operates properly.

i The containment design has been examined to establish the allowablg bypass area between the drywell and suppression chamber as 0.12 ft .

This is equivalent to one vacuum breaker open by three-eighths of an inch (3/8') as measured at all points around the circumference of the disk or three-fourths of an inch (3/4') as measured at the bottom of

the disk when the top of the disk is on the seat. Since these valves open in a manner that is purely neither mode, a conservative l allowance of one-half inch (1/2') has been selected as the maximum 4 permissible valve opening. Assuming that permissible valve opening could be evenly divided among all ten vacuum breakers at once, valve opan position assumed to indication for an individual valve must be
activated less than fifty-thousandths of an inch (0.050') at all points along the seal surface of the disk. Valve closure within this limit may be determined by light indication from two independent position detection and indication systems. Either system provides a i control room alarm for a nonseated valve.

Amendment No. GG, 128 168 q- y ---t--t 7- ww r -

e-- ,6 -e e Yc'

VYNPS

4. An evaluation of the change, which shows the predicted releases of radioactive materials in liquid and gaseous effluents and/or quantity of solid waste that dif fer from those previously predicted in the license application and amendments thereto;
5. An evaluation of the change, which shows the expected maximum exposures to member (s) of the public at the site boundary and to the general popula*:fon that differ from those previously estimated in the .icense application and amendments thereto;
6. A comparison of the predicted releases of radioactivw materials, in liquid and gaseous effluents and in solid waste, to the actual releases for the period prior to when the changes are to be made
7. An estimate of the exposure to plant operating personnel as a result of the change; and
8. Documentation of the fact that the change was reviewed and found acceptable by PORC.

B. Shall become effective upon review and acceptance by PORC and approval by the Plant Manager.

V V r-->- 6.15 Pr4 == w conPai a=== t tamh=ae Rate Testinct Prosrant A program shall be established to implement the leakage race testing of the primary containment as required by 10 i Oi CFR 50.54(o) and 10 CFR 50, Appendix J, Option B as modified by approved exemptiens. This program shall be

- in accordance with the guidelines contained in Regulatory Guide 1.163, entitled " Performance-Based Containmer.c Leak-Test Program,a dated September 1995.

1 The peak calculated containment internal pressure for the I design basis loss of coolant accident, Pa, is 44 psig.

The maximum allowable primary containment leakage race, La, at Pa, shall be 0.8% of primary containment air weight per day.

Leakage rate acceptance criteria are: I

1. Primary containment leakage rate acceptance criterion is s 1.0 La.
2. The as-left primary containment integrated leak rate test (Type A teht) acceptance criterion is s 0.75 La.
3. The combined local leak rate test (Type B & C tests) acceptance criterion is s 0.60 La, calculated on a maximum pathway basis, prior to entering a mode of operation where containment integrity is required.
4. The combined local leak rate test (Type B & C tests) acceptance criterion is s 0.60 La, calculated on a minimum pathway basis, at all times when primary containment integrity is required.
5. Airlock overall leakage rate acceptance criterion is s 0.10 La when tested .st a Pa. ,

1 The provision of the Definition (1.0.Y) for Surveillance Frequency does not apply to the test frequencies specified in the Primary Containment Leak Rate Testing Amendment No. 44, 95 _

,A 279 l

4 Vermont Yankee Proposed Change No.190 New Technical Specification pages A

4 I

h'

VYNPS

'3.7 LIMITING CONDITIONS FOR 4.7 SURVEILLANCE REQUIREMENTS OPERATION

e. Minimum Water Volume -

68,000 cubic feet

f. Maximum Water Volume -

70,000 cubic feet

2. Primary containment 2. The primary containment integrity shall be integrity shall be maintained at all times demonstrated as required wher. the reactor is by the Primary

. critical or when the Containment Leak Rate reactor water Testing Program temperature is above (PCLRTP).

2120F and fuel is in the reactor vessel except while performing low power physics tests at atmospheric pressure at power levels not to exceed 5 Mw(t).

3. If a portion of a system 3. (Blank) l that is considered to be an extension of primary containment, as detailed in the PCLRTP, is to be opened, isolate the affected penetration flow path by use of at least one closed and deactivated automatic valve, closed manual valve or blind flange.
4. Whenever primary 4. The leakage from'any one l containment is required, main steam line l the leakage from any one isolation valve shall main steam line not exceed 11.5 scf/hr isolation valve shall at 24 psig (Pt). Repair noc exceed 15.5 scf/hr and retest shall be at 44 psig ( P,) . conducted to insure compliance.

Amendment No. M , 147

1 VYNPS I 3.7 LIMITING CONDITIONS FOR 4.7 SURVEILLANCE REQUIREMENTS OPERATION

5. Core spray and LPCI pump 5. The core spray and LPCI lower compartment door lower compartment openings shall be closed openings shall be at all times except checked closed daily.

during passage or when j reactor coolant 1 temperature is less than 212oF.

D. Primary Containment D. Primary Containment i Taolation Valves Isolation Valves l

1. During reactor power 1. Surveillance of the operating conditions all primary containment l containment isolation isolation valves should valves and all be performed as follows:

instrument line flow check valves listed in a. The operable ,

the PCLRTP shall be isolation valves l operable except as that are power I specified in operated and Specification 3.7.D.2. automatically initiated shall'be tested for automatic initiation and the closure times specified in Table 4.7.2 at a least once per operating cycle,

b. Operability testing of the primary containment isolation valves shall be performed i in accordance with specification 4.6 E. I
c. At least once per quarter, with the reactor power less than 75 percent of rated, trip all j main steam '

isolation valvec (one at a time) and ,

verify closure l time,

d. At least twice per week, the main steam line isolation valves shall be exercised by partial closure and subsequent reopening.

Amendment No. 60, B6, 144, +14, 147, 156

, .~ .. . -- - . - -. . . . . . . .- - .._ - . .-

e .

VYNPS 3.7 LIMITING CONDITIONS FOR 4.7 SURVEILLANCE REQUIREMENTS OPERATION 4

2. In the event any 2. Whenever a containment l containment isolation isolation valve listed valve specified in the in the PCLRTP is l PCLRTP becomes inoperable, the position inoperable, reactor of at least one other power operation may salve.in each line continue provided at having an inoperable least one valve in each valve shall be logged line having an daily, inoperable valve is in the mode corresponding to the isolated condition.
l 3. If Specifications 4 3.7.D.1 and 3.7.D.2 cannot be met, an-orderly shutdown shall i be initiated and the reactor shall be in the cold shutdown condition

, within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />.

1 1

i 1

4 1

1-i i

$~

l Amendment No. 157

. . . . - ~ . _ - . - . . . . . . - . _ . .. - . . _ . . .- . .-= . . - .

A VYNPS

.l This page intentionally left blank.

I l

i i

l i

4 l;-Amendment No. 158

.r x- .n , . .-. . ~ ,- .-. . - - . . . . . . . . . . . .

e 1

VYNPS

' l' TABLE 4.7.2 PRIMARY CONTAINMENT ISOLATION VALVES I

Number of Power.

Operated Valves Maximum nction on

, Isolation- Operating Normal 71itiating Group (1) Valve Identification Inboard Outboard . Time-(sec) -Position Sicrnal 1 Main Steam Line Isolation (2-80A, D& 4 4 5 (Note 2). Open GC 2-86A, D) 1 Main Steam Line Drain (2-74, 2-77) 1 1 35 Closed SC ,

1 Recirculation Loop Sample Line (2-39, 2-40) 1 1 5 Closed SC l 2 RHR Discharge to Radwaste'(10-57,.10-66) 2 25 Closed 'SC 2 Drywell Floor Drain (20-82,- 20-83) 2 20 Open 'GC 2 Drywell Equipment Drain (20-94, 20-95) 2 20 Open GC

, 3 Drywell' Air Purge Inlet (16-19-9) 1 10 Closed SC

l 3 Drywell Air Purge Inlet'(16-19-8)- 1 10 Closed SC --

3 Drywell Purge & Vent Outlet-(16-19-7A) 1 10 Closed

  • SC 3 Drywell Purge & Vent Outlet Bypass 1 10 Closed- SC (16-19-6A) 3 Drywell & Suppression Chamber Main Exhaust 1 10 Closed
  • SC (16-19-7) 3 Suppression Chamber Parge Supply (16-19-10) 1 10 Closed SC l 3 Suppression Chamber Purge & Vent-Outlet 1 10 Closed SC (16-19-7B) 3 Suppression Chamber Purge & Vent Outlet 1 10 Open GC Bypass (16-19-6B)
  • Valves 16-19-7 and 16-19-7A shall have stops installed to limit valve opening to 500 cr less.

Amendment No. 6G, 9E 4-34 , 159

e e

VYNPS l TABLE 4.7.2 (Cont'd)

PRIMARY CONTAINMENT ISOLATION VALVES l

Number of Power Operated Valves Maximum Action on Isolation Operating Normal Initiating Group (1) Valve Identification Inboard Outboard Time (sec) Pocition Signal 3 Exhaust to Standby Gas Treatment System 1 10 Open GC (16-19-6) l 3 Containment Parge Supply (16-19-23) 1 10 closed SC l 3 Containment Makeup Supply (16-20-22A) 1 NA Closed SC 3 Containment Makeup Supply (16-20-20, 2 5 Open GC 16-20-22B) 5 Reactor Cleanup System (12-15, 12-18) 1 1 25 Open GC 6 HPCI (23-15, 23-16) 1 1 55 Open GC 6 RCIC (13-15, 13-16) 1 1 20 Open GC Primary / Secondary Vacuum Relief (16-19-11A, 2 NA Closed SC 16-19-11B)

Primary / Secondary Vacuum Relief (16-19-12A, 2 NA Closed Process 16-19-12B) 3 Containment Air Sampling (VG 23, VG 26, 4 5 Open GC 109-76A&B)

Feedwater Check Valves (V2-27A, -96A, ~28A, NA Open Process

-28B) i Amendment No. 56, G, -74,  % , 24, 160

e e

VYNPS l TABLE 4.7.2 (Cont'd)

PRIMARY CONTAINMENT ISOLATION VALVES 1

Number of Power Operated Valves Maximum Accion on Isolation Operating . Normal Initiating Group (1) Valve Identification Inboard Outboard Time (sec)- Position Signal r

2 RHR Return to Suppression Pool (10-39A, B) 2 70 Closed SC 2 RHR Return to Suppression Pool (10-34A, B) 2 123 Closed SC 2 RHR Drywell Spray (10-26A, B& 10-31A, B) 4 70 Closed SC 2 RHR Suppression Chamber Spray (10-38A, B) 2 45 Closed SC 3 Containment Air Compressor Suctic.n (72-38A, 2 20 Open GC B) 4 RHR Shutdown Cooling Supply (10-18, 10-17) 1 1 28 Closed SC Standby Liquid Control Check Valves (11-16, 1 1 NA . Closed Proc.  ;

11-17) +

3

  • Hydrogen Monitoring (109-75 A, 1-4; 10 NA NA NA I

109-75 E-D, 1-2)

Sampling Valves - Inlet

  • Hydrogen Monitoring (VG-24, 25, 33, 34) 4 NA NA NA i

5

  • These valves are remote manual sampling valves which do not receive an isolation signal. Only one valve in each line is required to be operable.

Amendment No. 68, 61, 1-M , M, 161 I,

o ,. : o i

1' l

i VYNPS l

l BASES: 4.7 (Cont'd) l

! The maximum allowable test leak rate at the peak accident pressure of 44 psig (La) is 0.80 weight % per day. The maximum allowable test leak rate at the ret'st pressure of 24 psig (Lt) has been conservatively detei ined to be 0.59 weight percent per day. This value will be verified to be conservative by actual primary containment leak rate measurements at both 44 psig and 24 psig upon i completion of the containment structure.

I As most leakage and deterioration of integrity is expected to occur ,

through penetrations, especially those with resilient seals, a l periodic leak rate test program of such penetration is conducted at the peak accident pressure of 44 psig to insure not only that the leakage remains occeptably low but also that the sealing materials can withstand the accident pressure.

The Primary Containment Leak Rate Testing Program is based on Option B to 10CFR50, Appendix J, for development of leak rate testing nd surveillance schedules for reactor containment vessels.

I Surveillance of the suppression Chamber-Reactor Building vacuum 1 breakers consists of operability checks and leakage tests (conducted as part of the containment leak-tightness tests). These vacuum breakers are normally in the closed position and open only during tests or an accident condition. Operability testing is performed in conjunction with Specification 4.6.E. Inspections and calibrations are performed during the refueling outages this frequency being based on equipment quality, experience, and engineering judgment.  ;

1 The ten (10) drywell-suppression vacuum relief valves are designed to j open to the full open position (the position that curtain area is equivalent to valve bore) with a force equivalent to a 0.5 psi differential acting on the suppression chamber face of the valve disk. This opening specification assures that the design limit of 2.0 psid between the drywell and external environment is not exceeded. Once each refueling outage each valve is tested to assure that it will open fully in response to a force less than that specified. Also it is inspected to assure that it closes freely and operates properly.

The containment design has been examined to establish the allowable bypass area between the drywell and suppression chamber as 0.12 ft2, This is equivalent to one vacuum breaker open by three-eighths of an inch (3/8") as measured at all points around the circumference of the disk or three-fourths of an inch (3/4") as measured at the bottom of the disk when the top of the disk is on the seat. Since these valves open in a manner that is purely neither mode, a conservative allowance of one-half inch (1/2") has been selected as the maximum permissible valve opening. Assuming that permissible valve opening could be evenly divided among all ten vacuum breakers at once, valve open position assumed to indication for an individual valve must be activated less than fifty-thousandths of an inch (0.050") at all points along the seal surface of the disk, Valve closure within this limit may be determined by light indication from two independent position detection and indication systems. Either system provides a control room alarm for a nonseated valve.

i l

I Amendment No. 59, lee, 168

x >

= 6.jA VYNPS

4. An evaluation of the change, which shows the predicted releases of radioactive materials in liquid and gaseous effluents and/or quantity of solid waste that differ from those previously predicted in the license application and amendments thereto;
5. An evaluation of the change, which shows the expected maximum exposures to member (s) of the public at the site boundary and to the general population that differ from those leeviously estimated in the license application and amendments thereto;
6. A comparison of the predicted releases of radioactive materials, in liquid and gaseous effluents and in solid waste, to the actual releases for the period prior to when the changes are to be made
7. An estimate of the exposure to plant operating personnel as a result of the change; and
8. Documentation c2 the fact that the change was reviewed and found acceptable by PORC.

B. Shall become effective upon review and acceptance by PORC and approval by the Plant Manager.

6.15 Primary Containment Leakage Rate Testing Program A program shall be established to implement the leakage rate testing of the primary containment as required by 10CFR50.54(o) and 10CFR50, Appendix J, Option B as modified by approved exemptions. This program shall be in accordance with the guidelines contained in Regulatory Guide 1.163, entitled

" Performance Based Containment Leak-Test Program," dated September 1995.

The peak calculated containment internal pressure for the design basis loss of coolant accident, Pa, is 44 psig.

The maximum allowable primary containment leakage rate, La, at Pa, shall be 0.8% of primary containment air weight per day.

Leakage rate acceptance criteria are:

1. Primary containment leakage rate acceptance criterion

~

< l.0 La. <

l l

2. The as-left primary containment integrated leak rate test (Type A test) acceptance criterion is < 0.75 La.
3. The combined local leak rate test (Type B and C tests) acceptance criterion is 5,0.60 La, calculated on a maximum pathway basis, prior to entering a mode of operation where containment integrity is required.

I

4. The combined local leak rate test (Type B and C teste) i acceptance criterion is 5,0.60 La, calculated on a minimum i pathway basis, at all times when primary containment i integrity is required. j

' 5. Air lock overall leakage rate acceptance criterion is 5,0.10 La when tested at > Pa.

The provision of the Definition (1.0.Y) for Surveillance Frequency does not apply to the test frequencies specified in the Primary Containment Leakage Rate Testing Program.

Amendment No. B3, 95, 279 l

p Vermont Yankee Proposed Change No.190 Selected References 1

t-VERMONT YAN KEE NUCLEAR POWER CORPORATION SEVENTY sCVEN GROVE STREET Run.mo, VEaMcNT osvoi 2.C.2.1 R. C. Ha'Juss PvY 82-32 J. E. Tribble asety vo, D. E. Vandenburgh L. H. Heider/D. E. Moody ENGINEERING OFFICE 1671 WORCESTER RC Ao D. W. Edwards /R. E. ' Helfrich March 26,1982 L. D. MarsolaiS FRAMINGHAM. M Ass 4cH usETTs oivoi TELaPMont et7.a72.eioo P. L. Smit.h B. Jwaszewski J. G. Robinson W. F. C4ieddyd States Nuclear Regulatory Commission R. KinnWyshington, D. C. 20555 RECENED A. M. Shepard-2 M n: Office of Nuclear Reactor Regulation W. P. Murphy-2 Mr. D. B. Vassallo, Chief yN J. P. Pelletier Operating Reactors Branch #2

{ D. A. Reid Division of Licensing J. Ritsher VERMONT YANKEE Mgr. of RikfereepeBas. Eda) License No. DPR-28 (Docket No. 50-271)

J. Calhoun (b) Letter, USNRC to VYNPC, dated November 9,1979 R. Saudek J. L:aser (c) Letter, VYNPC to USNRC, WVY-81-15, dated January 21, 1980 4

(d) Letter, USNRC to VYNPC, dated September 10, 1980 Lic. File Chrono (e) Letter, VYNPC to USNRC, WVY 80-139, dated October 3, 1980 D. E. Lapp (f) Letter, USNRC to VYNCP, dated March 3,1981 (g) Letter, VYNPC to USNRC, FVY 81-83, dated May 21, 1981 M.-Rice K. G. S6mbdec t : Operation of Purge and Vent Valves Under J.aerting Conditions H. C. Shaffer T. CizaashrsSir:

The most recent revision to 10CFR50.44 requires Vermont Yankee to inert its primary containment by May 4,1982. Installation of the necessary equipment for inerting is in progress, and we intend to meet the May 4,.1982 deadline. Present operation of the purge and vent valves at Vermont Yankee is j l

administrative 1y limited to the minimum usage requifed to maintain a drywell to torus differential pressure of 1.7 psid. However . af ter May 4,1982, with the containment inerted, it will be necessary to modify the operation of the purge and vent valves as described in Enclosure I to this letter. Ve rmont Yankee's bases for this mode of operation are discussed below.

The NRC requested Vermont Yankee to comply with an interim position on purging and venting in Reference (b). Our compliance was documented in Reference (c) and acknowledged by the NRC in Reference (d). In Reference (e),

Vermont Yankee stated that data supplied by the manufacturer of the purge and vent valves demonstrated that these valves are capable of operating as required

  • under the most severe design bcsis accident flow (LOCA) conditions. Subsequent to that submittal, we received Reference (f) which requested additional i information on the subject valves. All of the information available to respond to Peference (f) at that time was submitted via Reference (g). Additional 4

information which has since been developed is presented in Enclosure II to this letter.

Vermont Yankee believes that, based on this infonnation, the purge and vent valves are capable of performing their intended function. However, in the int e rim, for those valves where the flow force tending to resist valve closure is considered potentially significant, the valve position will be limited as

  • . . L E> ' l Mt. D. B. Vsssello March 26, 1982 Page 2 dictated by the flow tests applicable to that particular valve. We feel that these interim measures will provide greater assurance of overall safe operation than limiting r.he us e of these valves to a fixed number of hours per year. It is also important to note that the largest of the purge and vent valves at our facility is only 18 inches in diameter, and that all purge and vent valves are ,

located inside our secondary containment. This precludes the possibility of a l release directly to the atmosphere in the unlikely event of a failure of one of these valves during a postulated accident.

Vermont Yankee believes that the information presented above and in the attachments to this letter provides a more than adequate basis for our proposed scheme of operation of the purge and vent valves. In addition, we believe that the new requirement for Vermont Yankee to inert, and the subsequent necessity of purging to deinert to provide safe access to the primary containment for maintenance, are acceptable reasons for using these valves as described in

~

Enclosure I. Other remaining questions, such as the seismic qualification of the purge and vent valves are being addressed as part of our long-term program.

As previously stated, Vermont Yankee will have to inert by May 4, 1982. l To meet the required date for inerting, we propose to test our system in early Ap ril . Therefore, your review of our proposed mode of operation concerning the purge and vent valves is necessary in advance of the May 4, 1982 date. We t ru s t the information transmitted by this letter is acceptable; however, should you have any questions, please contact us.

Very truly yours l

VERMONT YANKEE NUCLEAR POWER CORPORATION l 91 w1 ,

4. w e h.

l 1

e

a .u W I

ENCLOSURE I Ve rmont Yankee Purge and Vent Valve s l

Description of Proposed Operating Modes to be used with Inerted Containment.

Objectives: 1. Maintain dif ferential pressure between drywell and torus.

2. Maintain inert atmosphere' of nitrogen during power operation.
3. Remove the inert atmosphere to provide a safe environment for personnel access to the drywell.
4. Achieve the requirements of Items 1, 2, and 3 in a timely fashion when needed.

l Normal Operation:

4, 4

Reactor at powe r.

i l 1.

4

2. Inert atmosphere in drywell and torus.
3. Differential pressure maintained.

These conditions are maintained by:

, a. Continuous supply of nitrogen 8as through one-inch makeup line and

two-inch instrument supply line.
b. Continuous vent of torus through wide open three-inch . butterfly valve, to PCAC piping, through eight-inch butterfly SB-6 to Standby Cas Treatment System with fan not running. (This mode of. operation was previously approved by the NRC in Reference (d) of the cover letter.) SBGT discharges through piping to the monitored stack. Drywell atmosphere is monitored for radioactive particles and gasses.

4 Inerting Operation:

1. Reactor at design temperature and pressure af ter startup from maintenance l and/or refueling conditions.
2. Inert atmosphere to be provided.
3. Differential pressure not required for 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> af ter achieving operating temperature and pressure.

Drywell inerting will be achieved as follows:

Gas will be introduced through six-inch piping, through a six-inch butterfly valve, wide open. The gas flows into eighteen-inch piping,

.. .Lb-I-

?

I through an eighteen-inch valve, wide open, to the drywell; and through an eighteen-inch valve, _ vide open to the torus.

1

Air will be exhausted from the drywell throu3h an eighteen-inch butterfly ,
j. valve, limited en'500 open. Air is exhaustou from the torus through an

[ eighteen-inch butterfly valve, wide open. Torus and drywell air flow j- through PCAC piping and through eighteen-inch SB-7; limited to 500 l

  • open. Air then flows through Reactor Transfer' Fan 5; then through the I
building exhaust piping, exhaust fan, and discharge piping to the l ionitored stack.

l- Purging Operation:

3. :1. Reactor at full power. l i
j. 2. Inert ' atmosphere in drywell and torus to be removed. I i

i 3. Differential pressure not required for 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> prior to commencing a

, ' shutdown.

< Purge air will be supplied from the Reactor Building ventilation supply duct i which is slightly pressurized by the building supply fans. Air flows from the

[ duct, into the PCAC eighteen-inch piping, through the backup eighteen-inch l butterfly valve, through the piping and through an eighteen-inch butterfly 1

valve to the torus, and an eighteen-inch buttefly valve to the.dryuell. These j butterfly valves are wide open.

l l The exhaust path is similar to that for inerting. Flow f rom the torus and drywell is through the valves and piping described, but initial exhaust may be through the Standby Gas Treatment System, if required by radiological conditions.

Ju st i fica t t'on : .)

1. . Per FRC regulations, .inerting is required to mitigate potential post-accident conditions.
2. Drywell purging is required to provide a safe atmosphere for personnel l performing necessary drywell activities.
3. Allis Chalmers valve tests demonstrate that all the installed butterfly valves can close from full open conditions at design basis containment pressure. This is true with flow through the valves in the post-LOCA di rectio n. However, as an additional conservatism, limit stops will be added to those valves where the flow force that tends to open the valve ,

is potentially significant as dictated by the flow tests applicable to I those particular valves.

Valve position will be limited by a design compatible with the Bettis Robot - Arm actuators. ,

O

, , , . , . . . - . . _ - _ . . . _ . _ _ . - . . . _ = . . . - . . . . _ - . _ - . - - .

s aub lf-e l* i l

Valve. Usage: I l- l Inerting Mode Position V-16-19-23. Wide open j V-16-19-8 Wide open

, V-16-19-10 . . Wide open l -

. V-16-19-73 Wide open V-16-19-7A Limited to 500 open j SB-6 Only one.open Wide open '

SB-7 at any time Limited to 500 open Purging Mode V-16-19-9 Wide open V-16-19-23 Closed i

All other purge and vent valves in same position as in Inerting }! ode.

D/P Maintenance Mode V-16-19-6B Wide open SB-6 Wide open l_

All other valves which are open in this mode are 3 inches or smaller and i connect to lines designed for containment pressure or higher (i.e. ,

i instrument air).

l 4

i l

e

, -- , w

e selb' 4

s

, . ENCLOSURE II 2

Ve rmont Yankee Purge and Vent Valves (Question Numbers refer to NRC letter to VYNPC dated l March 3, 1981. The previous. response indicated is a Vermont Yankee letter to NRC dated May 21, 1981.)

-Questiun 2: What are identified as the critical parts in these valves

]

~

(shaft, disc to shaft pins, other)? What were the stresses

~ calculated? Do they include simultaneous seismic loading?

)

' What- are the design allowable stresses? What code or standards are the valves designed to?

[.-

[ Inf ormation on 6" _ SB-16-19-23 is provided based on information supplied by the ve ndor. Additional information will be developed and reported as part of our r long-term program.

Calculated Stress Valve Critical Part Due to Pressure Design Allowable 4

e 6" SD-16-19-23 4

  • Disc-bendin8 5140 psi 17,500 psi Shaft 3915 psi 30,000 psi 1 Bearings _ 1050 psi 20,000 psi Operator Mounting Shear 1817 psi 54,000 psi Bolts Tensile 2282 psi

' Question 4: Is there sufficient torque margin available from the operator j to overcome the torques developed that tend to oppose valve

closure as the valve strokes from its initial open position to i the fully seated position? What is the minimum margin
available, and at what disc angle does this ninimum exist?

e t

For Valve 16-19-7B

Angle at minimum margin 700 Margin (available torque-opposing torque) 2I3 ft-lb Question 7: '(Dealt with environmental qualification of pilot solenoids.)

1-Since May,1981, all these solenoids have been replaced or determined to be 3 qualified for their intended use.

p Question 8: Describe the extent to which the operators are seismically

[

2 qualified and environmentally qualified for long-term exposure to the normal plant environment. If the purge valves are to be operative post-LOCA, describe the extent to which the operators are . environmentally qualified for the LOCA environment. Do the

, elastomeric parts in the operatar have a qualified design life l-i.

, where periodic replacement is required?

2 The previous response referred to the answer to Question 7 which dealt with the opera tors' solenoids. Please replace it with the following:

I k

4 4

v - . - - ~ . - - , ..--c., . - , . - - . , - - , .n- u

j i ,. . Jh l All these valves were purchased for, and are located in, the reactor building

! in areas of mild environmental conditions. In the nearly ten years of plant '

j operation, to date, there has been no evidence of environmental impairment of these valves' functions. These valves are not required to be operative post-LOCA in the long-term. If open, they would close immediately to isolate the containment. Thereaf ter, they would remain closed. These valves are all 1

held closed by springs. Vermont Yankee has specified operability of the l valves at the end of a year following a TMI-type accident in the scenario used l

fpp, determining electrical equipment qualification (I&E Bulletin 79-018). At that time, the valves would be opened to purge the primary containment and begin post-accident cleanup. Were these valves not to be operable, the reactor buiding would be entered and the valves repaired. These valves are all located outside the primary containment. The post-LOCA environment would consist of the building heatup and radiation cloud. Disc seat material was specified for 300"F.

The operators contain rubber (HYCAR) cylinder rod and piston seals good for 2 x 106 rads. Periodic replacement is not required.

Valves will normally be closed during inerted operation, and are spring closed. Therefore, capability of pneumatic parts to open the valves is not safety-related.

1 Final resolution of seismic qualification will be part of our long-term program.

r

J. E. Tribble D. E. Vandenburgh l

. /p %q[o., UNITED STATES L. H. Heider l y, () j p, NUCLEAR REGULATORY COMMISSION D. W. Edwards /R. E. Helf rich s .g ,

WASHINGTON, D. C. 20555 QV,gg2

%, .4 / R. L. Smith

..... J. D. Baseltine May 3,1982 L. D. Marsolais

- EEC" NVY 82-60 A. M. Shepard-2 Docket No. 50-271 fjfq f g!:! W. P. Murphy-2 D. A. Reid l j YEGI ATOU.IC J. P. Pe11etter R. Kenney Mr. Robert L. Smith B. Jwaszewski Licensing Engineer KEW5@W t J. G. Robinson

. Vermont Yankee Nuclear Power a,p, pam-j W. F. Conway Corporation R. E. Lapp ,

1671 Worcester Road R6 W4 hd.: c. M. Rice Framingham, MA 01701 g . d 8 2. R. G. Staker P. S. Littlefield

Dear Mr. Smith:

original-Licensing File Copy

Subject:

Operation of Purge and Vent Valves Under Inerted Conditions l

Reference:

Letter March 26, 1982 from Vermont Yankee Nuclear Power j Corporation (Vermont Yankee Nuclear Power Station)

In your letter dated March 26, 1982 you informed us of the manner in which

you propose to operate the containment purge and vent valves in complying
with the requirements of 10 CFR 50.44 to operate with an inerted

~

containment by May 4, 1982 and asked that we review your proposal.

Our review of your proposal considered only the changes between your previous manner of operation and your proposed manner of operation. However, 1 other requirements may develop upon completion of our long-tenn review of a the containment purge and vent issue.

We conclude that operation in the manner you describe is acceptable, except

that during modes other than cold shutdown or refueling valve SB-16-19-9 is required to be sealed closed, as defined in Standard Review Plan Section 6.2.4, Item II.6.f. The reason for this requirement is that we have information from the valve manufacturer that leads us to believe that for this valve in its present orientation high torques could exist even in the very low angles of opening. This indicates the interim position of partially blocking the valve to a maximum opening of between 35 and 500 may not sufficiently reduce the high torques imposed on this valve from

, a LOCA. You should provide justification by means of additional test /

analysis work in order to use valve SB-16-19-9 in its present orientation or reorient this valve.

Our conclusion is based on our understanding from discussions with your staff that your proposed manner of operation involves no changes in logic or circuitry. Please infonn us if this is not correct. RECEIVED MAY 101982 VERMONT YANKEE

l Mr. Robert L. Smith 2 i s

l In addition, please provide us with your estimate of the maximum number of a

hours per year you expect to purge (or vent) and the estimated amount of radioactivity release during the time required to close the valve (s) following a LOCA as compared to 10 CFR Part 100 guidelines. Please provide this infomation within 30 days of receipt of. this letter.

)

The reporting and/or recordkeeping requirements contained in this letter affect fewer than ten respondents; therefore, OMB clearance is not required under P.L.96-511.

4 Sincerely, 2

Domenic B. Vassallo, Chief Operating Reactors Branch #2 Division of Licensing cc: See next page l

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