Text

Tech Specs 3.4.7.2,3/4.5.1,3.5.1.1,4.5.1.1,3/4.5.3,3.5.5.3, 4.5.3.1,4.5.3.2,3.8.1.2,3.11.2.5,4.11.2.5 & Tables 3.4-1, 3.7-6 & 3.3-13 Re Oxygen Concentration in Waste Gas Holdup Sys,Hydrogen Monitor Requirements Et Al
	ML20008E635
Person / Time
Site:	McGuire
Issue date:	02/23/1981
From:	; DUKE POWER CO.
To:	;
Shared Package
ML20008E634	List: ML20008E633; ML20008E635;
References
	TAC-46812, NUDOCS 8103090310
	Download: ML20008E635 (11)
	v • d • e

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Attachment 1

Duke Power Company i McGuire Nuclear Station i

I- Proposed Technical Specification Revision

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Pages l

i- 3/4 3-62 ,

3/4 4-18 ,

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3/4 4-20 I

l 3/4 5-1

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3/4 5-9 3/4 5-10 i

3/4 7-60 3/4 8-9 3/4 11-16 4

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8108090 @ f J

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t w d w ame w2 V Pa e-W --m m e WMMy-w w wrms tw-rw- _.. wpm [

i i REACTOR COOLANT SYSTEM U(N OPERATIONAL LEAKAGE LIMITING CONDITION FOR OPERATION 3.4.7.2 Reactor Coolant System leakage shall be limited to:

a. No PRESSURE BOUNDARY LEAKAGE,

b. 1 GPM UNIDENTIFIED LEAKAGE,

c. 1 GPM total primary-to-secondary leakage through all steam generators and 500 gallons per day through any one steam generator.

d. 10 GPM IDENTIFIED LEAKAGE from the Reactor Coolant System,

e. 40 GPM CONTROLLED LEAKAGE at a Reactor Coolant System pressure of 2235 + 20 psig, and APPLICABILITY: MODES 1, 2, 3 and 4

f. 1 GPM leakage from any Reactor Coolant System Pressure Isolation

/m\ Valve specified in Table 3.4-1.

(J APPLICABILITY: MODES 1 and 2 ACTION:

a. With any PRESSURE B0UNDARY LEAKAGE, be in at least HOT STANDBY within 6 hours6.944444e-5 days 0.00167 hours 9.920635e-6 weeks 2.283e-6 months and in COLD SHUTDOWN within the following 30 hours3.472222e-4 days 0.00833 hours 4.960317e-5 weeks 1.1415e-5 months .

b. With any Reactor Coolant System leakage greater than any one of the above limits, excluding PRESSURE B0UNDARY LEAKAGE and leakage from Reactor Pressure Isolation Valves, reduce the leakage rate within 4 hours4.62963e-5 days 0.00111 hours 6.613757e-6 weeks 1.522e-6 months or be in at least HOT STANDBY within the next 6 hours6.944444e-5 days 0.00167 hours 9.920635e-6 weeks 2.283e-6 months and l in COLD SHUTDOWN within the following 30 hours3.472222e-4 days 0.00833 hours 4.960317e-5 weeks 1.1415e-5 months .

c. With any Reactor Coolant System Pressure Isolation Valve leakage greater than the above limit, isolate the high pressure portion of the system from the low pressure portion within 4 hours4.62963e-5 days 0.00111 hours 6.613757e-6 weeks 1.522e-6 months by use of' at least two closed manual or deactivated automatic valves, or be in at least HOT STANDBY within the next 6 hours6.944444e-5 days 0.00167 hours 9.920635e-6 weeks 2.283e-6 months and in COLD SHUTDOWN within the following 30 hours3.472222e-4 days 0.00833 hours 4.960317e-5 weeks 1.1415e-5 months .

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McGUIRE - UNIT 1 3/4 4-18

TABLE 3.4-1 V REACTOR COOLANT SYSTEM PRESSURE ISOLATION VALVES i

VALVE NUMBER FUNCTION MC-1562-2.0 l'

1NI60 Accumulator Discharge 1NI71 Accumulator' Discharge 1NI59 Accumulator Discharge L INI70 Accumulator Discharge [

I MC-1562-2.1 INM82 Accumulator Discharge 1NI94 Accumulator Discharge 1NI81 Accumulator Discharge 1NI93 Accumulator Discharge MC-1562-3.0 INI159 Safety Injection (Hot Leg) 1NI156 Safety Injection (Hot Leg) 1NI128 Safety Injection (Hot Leg) 1NI124 Safety Injection (Hot Leg) .

1NI160 Safety Injection (Hot Leg)

INI157 Safety Injection (Hot Leg)

IN1126 Safety Injection (Hot Leg)

,Q MC-1562-3.1 1NI165 Safety Injection / Residual Heat Removal (Cold Leg)

INI167 Safety Injection / Residual Heat Removal (Cold Leg)

INI169 Safety Injection / Residual Heat Removal (Cold Leg)

INI171 Safety Injection / Residual Heat Removal (Cold Leg) 1NI175 Safety Injection / Residual Heat Removal (Cold Leg) 1NI176 Safety Injection / Residual Heat Removal (Cold Leg) 1NI180 Safety Injection / Residual Heat Removal (Cold-Leg)

INI181 Safety Injection / Residual Heat Removal (Cold Leg)

MC-1562-4.0 1NI250 Upper Head Injection

1NI251 Upper Head Injection 1NI252 Upper Head Injection 1NI253 Upper Head Injection 1NI249 Upper Head Injection 1NI248 Upper Head Injection MC-1561-1.0 1NDIB* Residual Heat Removal IND2A* Residual Heat Removal I Testing per Section 4.4.7.2.2.d ne' applicable due to positive indication of valve positson in Control Room.

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McGUIRE - UNIT 1 3/4 4-20

3/4.5 EMERGENCY CORE COOLING SYSTEMS D

() 3/4.5.1 ACCUMULATORS COLD LEG INJECTION ACCUMULATORS i

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LIMITING CONDITION FOR OPERATION f

3.5.1.1 Each cold leg injection accumulator shall be OPERABLE with: (

a. The isolation valve open,

b. A contained borated water volume of between 8261 and 8496 gallons, i

c. Between 1900 and 2100 ppm of boron, and

d. A nitrogen cover-pressure of between 400 and 454 psig.

APPLICABILITY: MODES 1, 2 and 3.*

ACTION:

a. With one cold leg injection accumulator inoperable, except as a result of a closed isolation valve, restore the inoperable cold leg injection accumulator to OPERABLE status within one hour or be in at O least HOT STANDBY within the next 6 hours6.944444e-5 days 0.00167 hours 9.920635e-6 weeks 2.283e-6 months and in HOT SHUTDOWN within b) the following 6 hours6.944444e-5 days 0.00167 hours 9.920635e-6 weeks 2.283e-6 months .

b. With one cold leg injection accumulator inoperable due to the isolation valve being closed, either immediately open the isolation valve or be in HOT STANDBY within one hour and be in HOT SHUTDOWN within the next 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months .

SURVEILLANCE REQUIREMENTS 4.5.1.1.1 Each cold leg injection accumulator shall be demonstrated OPERABLE:

a. At least once per 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months by:

1. Verifying, by the absence of alarms, the contained borated water volume and nitrogen cover-pressure in the tanks, and

2. Verifying that each cold leg injection accumulator isolation valve is open.

Pressurizer pressure above 1000 psig, g McGUIRE - UNIT 1 3/4 5-1 N.)

EMERGENCY CORE COOLING SYSTEMS I 0

3/4.5.3 ECCS SUBSYSTEMS - T,yg less than 350 F r

LIMITING CONDITION FOR OPERATION 3.5.3 As a minimum, one ECCS subsystem comprised of the following shall be OPERABLE:

a. One OPERABLE centrifugal charging pump, # ,

b. One OPERABLE residual heat removal heat exchanger,

c. One OPERABLE residual heat removal pump, and

d. An OPERABLE flow path capable of taking suction from the refueling water storage tank upon being manually realigned and transferring suction to the containment sump during the recirculation phase of operation.

APPLICABILITY: MODE 4 ACTION:

a. With no ECCS subsystem OPERABLE because of the inoperability of either the centrifugal charging pump or the flow path from the refueling water storage tank, restore at least one ECCS subsystem to OPERABLE status within 1 hour1.157407e-5 days 2.777778e-4 hours 1.653439e-6 weeks 3.805e-7 months or be in COLD SHUTDOWN within the next 20 hours2.314815e-4 days 0.00556 hours 3.306878e-5 weeks 7.61e-6 months ,

b. With no ECCS subsystem OPERABLE because of the inoperability of either the residual heat removal heat exchanger or residual heat removal pump, restore at least one ECCS subsystem to OPERgBLE status or maintain the Reactor Coolant System T less than 350 F by use of alternate heat removal methods, avg

c. In the event the ECCS is actuated and injects water into the Reactor Coolant System, a Special Report shall be prepared and submitted to the Commission pursuant to Specification 6.9.2 within 90 days describing the circumstances of the actuation and the total accumulated actuation cycles to date. The current value of the usage factor for each affected safety injection nozzle shall be provided in this Special Report whenever its value exceeds 0.70.

l#A maximum of one centrifugal charging pump or safety injection pump shall be l m OPERABLE whenever the temperature of one or more of the RCS cold legs is less

} than or equal to 3000F. ,

J McGUIRE - UNIT 1 3/4 5-9

EMERGENCY CORE COGLING SYSTEMS O

SURVEILLANCE REQUIREMENTS 4.5.3.1 The ECCS subsystem shall be demonstrated OPERACLE per the applicable Surveillance Requirements of 4.5.2.

4.5.3.2 All charging pumps and safety injection pumps, except the above l required OPERABLE charging pump or safety injection pump, shall be demonstrated l inoperable at least once per 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months whenever the temperature of one or more of the RCS cold legs is less than or equal to 3000F by verifying that the motor circuit breakers have been removed from their electrical power supply circuits.

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McGUIRE - UNIT 1 3/4 5-10 i

. _ . _ _ _ . = _

l TABLE 3.7-6 O- FIRE HOSE STATICNS i LOCATION ELEVATION 55-FF 695 ft.

i- 52-CC 716 ft.

I 54-GG 716 ft.

55-MM 716 ft.

51-MM 716 ft.

i 40-AA 733 ft.

i 40-CC 733 ft.

43-00 733 ft. E p 46-AA 733 ft. L 52-DD 733 ft.

I I 52-EE 733 ft.

4 54-GG 733 ft.

j -JJ 733 ft.

! -MM 733 ft.

l- db-NN 733 ft.

! 46-CC 750 ft.

51-CC 750 ft.

j 52-AA 750 ft.

? 54-8B 750 ft.

I \ 56-00 750 ft. l

! 58-8B 750 ft.

i 52-GG 750 ft.

l 54-LL 750 ft.

i 50-MM 750 ft.

I' 56-QQ 750 ft.

51-BB 767 ft.

! 56-GG 767 ft.

! 54-JJ 767 ft. !

j 51-MM 767 ft.

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McGUIRE - UNIT 1- 3/4 7-60 1

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ELECTRICAL POWER SYSTEMS

('~))

\- SHUTDOWN LIMITING CONDITION FOR OPERATION i

i 3.8.1.2 As a minimum, the following A.C. electrical power sources shall be :

OPERABLE: i

a. One circuit between the offsite transmission network and the onsite ,

essential auxiliary power system, and (

b. One diesel generator with:

1. A day tank containing a minimum volume of 120 gallons of fuel,

{

2. A fuel storage system containing a minimum volume of 28,000 I gallons to fuel, and i

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3. A fuel transfer pump.

APPLICABILITY: MODES 5 and 6. 7 i

ACTION:

With less than the above minicum required A.C. electrical power sources l

! . OPERABLE, suspend all operations involving CORE ALTERATIONS or positive reactivity changes.

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SURVEILLANCE REQUIREMENTS !

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4.8.1.2 The above required A.C. electrical power sources shall be demonstrated ;

OPERABLE by the performance of each of the Surveillance Requirements of 4.8.1.1.1, ;

l 4.8.1.1. 2 and 4.8.1.1.4 except for Requirement 4.8.1.1. 2. a. 5. l l l

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\s / l McGUIRE - UNIT 1 3/4 8-9

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4 RADIOACTIVE EFFLUENTS I EXPLOSIVE GAS MIXTURE LIMITING CONDITION FOR OPERATION s

I 3.11.2.5 'The concentration of oxygen in the waste gas holdup system shall be i

l limited to less than or equal to 3% by volume whenever the hydrogen concentra- l t tion exceeds 4% by volume.

APPLICABILITY: At all times.

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ACTION: ;

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a. With the concentration of oxygen in the waste gas holdup system

g greater than 3% by volume but less than or equal 4% by volume, l i reduce the oxygen concentrati.on to the above limits within 48 hours5.555556e-4 days 0.0133 hours 7.936508e-5 weeks 1.8264e-5 months .

b. With the concentration of oxygen in the waste gas holdup system i,

greater than 4% by volume immediately suspend all additions of waste i gases to the system and reduce the concentration of oxygen to less than or equal to 4% by volume within one hour, and 3% by volume ,

within 48 hours5.555556e-4 days 0.0133 hours 7.936508e-5 weeks 1.8264e-5 months after initially exceeding 3% by volume.

l c. The provision? of Specifications 3.0.3 and 3.0.4 are not applicable.

SURVEILLANCE REQUIREMENTS 4.11.2.5 The concentrations of hydrogen and oxygen in the waste gas holdup

, system shall be determined to be within the above limits by continuously l monitoring the waste gases in the waste gas holdup system with the oxygen g monitors required OPERABLE by Table 3.3-13 of Specification 3.3.3.9.

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McGUIRE - UNIT l' 3/4 11-16 i i

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e-e- e- --wF - *- TV+ - = - +^ =

F-F - e'- +

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x "g TABLE 3.3-13 y RADI0 ACTIVE GASEOUS EFFLUENT MONITORING INSTRUMENTATION MINIMUM CHANNELS E INSTRUMENT OPERABLE APPLICABILITY ACTION q

- 1. WASTE GAS HOLDUP SYSTEM

a. Noble Gas Activity Monitor - Providing

35 Alarra and Automatic Termination of Release 1 (EMF-50 or 36) *

b. Effluent System Flow Rate Measuring Device 1 36

2. WASTE GAS Il0LDUP SYSTEM EXPLOSIVE GAS MONITORING SYSTEM

- 39 g a. Oxygen Monitors 2 ;

a l l

y 3. CONDENSER EVACUATION SYSTEM

a. Noble Gas Activity Monitor (EMF-33) 1

37 I

4. VENT SYSTEM

a. Noble Gas Activity Monitor ' EMF-36) 1 37

b. Iodine Sampler 1 40

. c. Particulate Sampler 1 40

36

d. Flow Rate Monitor

1

36 i e. Sampler Flow Rate Monitor 1 l i

To be installed by JuTy 1, 1981. Prior to this date, flow will be determined by sununing the '

flow measured on all inputs to the vent.

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--;% Attachment 2 i Duke Power Company f McGuire Nuclear Station '

Justification for the Proposed Technical Specification Revisions f Specification 3.4.7.3 and Table 3.4-1 l Meaningful leak rate testing can only be accomplished upon full !

seating of the valves required to be tested. The Mode 2 allowable j i

pressure will produca a more accurate leak rate calculation since i i

it more closely represents actual operating conditions. !

The four check valves (1 nil 59, 1 nil 56, 1 nil 28 and 1NI124) are to [

be tested instead of the two motor-operated valves (lNIl21A and -

1NI52B). The testing of these check valves can be accomplished with i l much less difficulty. Since these valves are located closer to the !

, system any leakage will have to travel through less pipe during the

[

1eak rate test and thus the leak rate measurements will be more ;

! accurate.

Action Statement page 3/4 4-18 part b -- typographical error: the l words "to within its limits" should be included.

O Table 3.7-6: typographical error: Fire hose station 56-DD 0 733 ft.

should read 56-DD @750 ft.

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Specification 4.8.1.2: typographical error: reference to Surveillance Requirement 4.8.11.4 should read 4.8.1.1.4. t Specification 3.11.2.5, 4.11.2.5 and Table 3.3-13: See attached letter.

Specification 3.5.1.1: The percentages which were specified are no !

longer valid and thus should be deleted. !

Specification 3.5.3 and 4.5.3.2: One operable safety injection pump P is needed for surveillance testing and to fill various accumulator I tanks during the time RCS cold leg temperatures are less than 300 F.

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Powca acit.ono !

r 4J2 Socr:: Cucucir Sturst,C L.mt. orts. N C. 2en: j.

I I 7 m....- s. .amaca.s a. January 12, 1931 t ur a.es.es., c.c..e .c: u s. :. i;

3.t.. a.co.cwo. . r s.. m r j

I! I a :

I I Mr. Harold R. Den:on, Direc:or l Office of :'uclear Reac:or Regula:1on L U. S. Nuclear Regulatory Coc ission {

Washington, D. C. 20555 l

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. Attention: Mr. 3. J. Youngblood, Chief f 4

Licensing Projects Branch No. 1 [

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Re: McGuire Nuclear Station l Docket No. 50-369, -370 t e

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Dear Mr. Denton:

L

] As discussed with Mr. J. Boegli and Mr. M. Virgilio of your Staf f on Jac.uary 9, 1 j 1981, please find attached a request for a change to the McGuire Technical ;

Specifications concerning explosive gas tixtures in: anks containing radio- !

ac:ive effluents. As discussed in the attached justification, the dest,;n of f

. the waste gis holdup system a: McGuire Nuclear Station is based on limi:ing [

] the concen::stion of oxygen in the system :o less than or equal :a :hree l percent oxygen by volume. Ex:ensive modifications would have to be made :o {

the system in order :o meet the NRC Staff proposed limit of two percen: '

oxygen by volu=e. I: is':herefore requestod that the requiremen: on the con-

centration of oxygen in the waste gas holdup sys: em be limi:ed to less :han or equal to three percent by volume. j t ;

I i In addition, as discussed in the jus:ificacion, since no mixture of hydrogen ;

and oxygen is fla=mable, with nitrogen ac:ing as :he diluent, belev five percent oxygen in a mix:ure, there appears to be no need for requirements 4

for a hydrogen monitor in this system in addition to the oxygen moni:or :

required by the technical specification. We therefore reques: that the require- l 3

ment for a hydrogen monitor in :he was:e gas holdup system be dele:ed. ;

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Please advise if you have any quest:.ons. l 3 s J

V .y truly yours,, l j

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.o j; M C Lu, A%'

i / William 0. Parker, J V t h

V LJB:scs Attach'ient l- A kll) W fb .

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. . 1 i- Mr. Harold R. Denton, Director

! January 12, 1981 1 - Page Two 1

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l ' bec: H. B. Tucker M. L. Birch j, K. S. Canady T. L. "cConnell

N. A. Rutherford R. H. Charest (CNS) l G. A. Copp T. B. Owen (ONS) (

l

, M. D.'McIntosh Master File MC-801.01 I 1

i W. M. Sample' Section File MC-801.01 j

! L. Lewis I R. O. Sharpe 1,

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V ?ROPOSF.3 TIC *afICAL SPECIFICA!!CN RI?!SICN A. .UDICACTIVE ?JFLUENTS EI?LUSIVE CAS ifI: CURE LIMITIM CCh*DITION FCR CPERA*ICN CicGuire Uni: Il r Technical Specification 3.11.2.6 now reads as f oll:ws: ,

3.11.2.6 "The :encentra ion of hydrogen and/cr Oxygen in :he vas:e gas l holdup sys:e= shall be li=ited :o 1 2" by *rolume.",

l Technical Specifica: ion 3.11.2,6 should be changed :s read as foll:ws:

3.11.2.6 ~he ::ncen::aci:n of Oxygen in :he was:e gaa holdup sys:a=

shall be li=1:ed :: 13* by roluce.

APPLICA3I' II"f : A: all :imes.

ACTION!

a. '41:h :he concentra:icn of Or/ gen in the was:e gas holdup svsta=

/w

\

> 3" by volu=e bu: -< 4* by volu=e, res:cra :na ::n=en::a:1:n f w oxygen :o wi:hin :he limi: in a3 hours,

b. *41:h the encentra:ica of oxygen in :he was:a gas holdup systa=

> a* Sy volume. *.:=ediatel/ suspend all addi:1:ns of waste gases :o :he sys:e= and reduce :he ::ncentra:ica :f crtgen ::

< 3" within 43 hours4.976852e-4 days 0.0119 hours 7.109788e-5 weeks 1.63615e-5 months .

SURVEI' LANCE RECUIRDfINTS The Surreillance Require =en:s should be changed :o read:

4.11.2.6 'he concen::a:icn of oxygen in :he vas:e gas heidup sys:e=

shall be de:er=ined :o be wi:hin :he above 11=1:s by continuously =oni-toring :he vas:e gases in :he was:e gas holdup sys:e= wi:h ':ne ar/ gen

=oni: ors required OPERA 3LZ by Table 3.3-12 of Scecificati:n 3.3.3.10.

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N REASC:IS A .*D JUSTIFICATICN FOR CHANGE

1) 3elow 5.0" Cxygen, no six:ure of hyd:cgen and oxygen,is fla==.sbie with ni:rogen ac:ing as :he ciluent in :his six:ure.* This is :he case for :he McGuire Was:e Gas System.

2) "The f ac: cha: a cembustible gas , vapor, c: ris: will no: burn c:

explode when the oxygen conten: of :he ate sphere is reducad below a certain defini:e value, varying w1:h :he ce= bus:1ble =acerial under consideration, enables one :o defini ely con::01 and in many cases ac:ually elisina:e explosien hazards."2

3) McGuira's Was:s 04s Systa= is designed :o cpers:e a: low oxygen

ncen::acicas (below 15 ppm in :he sys:e=, excluding por:icas of

he rece biner skid) w1:h a hydrogen recccciner in opera:i:n. The Ox7sen f eed valve :s :he hyd:cgen reccabiner can never pass nore

han 3.C% cxygen w1:hou: causing an alarm which ::1ps :he Oxygen feed valve :lesed. An inle exygen c:ncen::a:1:n :: :he hydrogen rece:biner of > 3.3% oxygen will :ause bc:h :he exygen f eed valve and :ne Vol;=e Cen:rol Tank hydrogen purge isola:icn valve (Uni: I and II) :o closa.

) The Waste Gas System is designed fc spera: icn in one of :he reo following =cdes: .

.(A) Compressor - Reco=biner - Decay Tank (3) Compresso - Decay Tank - Rece=bine Design of :he sys:a is such cha: Operati:n begins in Moda (A) un:11 approx 1:a:ely 25 psig is reached in :he decay :ank. A: :his poin:

he valve align =en should be swi::hed :o Mede (3). The hyd:: gen purge f:cm each VCT vill normally be app;cxima:aly 0.75 3CTM. With a ::mbined VCT purge (bo:h uni:s) of 1.3 3C7M :here is 3.75 hyd::-

gen in :he WG Sys:am a: the poin: where ':his purge mixes w1:h dr.e WO l ep flow (approxi=a ely 40 SC7M) . The reccc iner is designed :s re=ove all bu: app;cxima:aly 0.1% H, which will pass to :he decay

ank. When :he decay tank reaches 20 - 25 psig, the valve slignmen:

of Compressor - Decay Tank - Rec::bine: mus : be made due o :he backpressure on :he recemoiner which exists with approxica:ely 20 psig in :he :ank. (Maximum recombiner design pressure is 30 psig.)

Mode 3 would normally be che means by which the :ank in Mede A is used and filled :o 1:s all wabla '*d- (approx 1:a:ely 100 psig -O psig). However, as :he Mode (3) diagram belcw shows, :his w:uld no:

se possible with the demands of the 3.11.2.5 Techni:21 3cecift:a:icn.

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MODE (A)

'CII: ! L IT.IIT II -

VC PURGE ,100: H2

, i CECAY s a,20 osig

, N TANK ,

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V c, JRECOW 1.4-2.4 3CD! , " '

3 '.'ER --

V 60 SCW. I (In ' cop) l l'

, COM?RESSCR , }

! ! 40 SCD!

('l.. L., ?issien Cases)

MODE (3) w.... .. L ,v,.il. v... , -

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10 3CEt (L /

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lxample: ylew from Uni:s I and Il = 1.4 3CyM (100: H,)

This would give a 3.5" H, concentration in :he Was:e Gas Sys tem loop, and eventually a 375% H, concentracien_in :he WG Decay Tank in service. ~ If the Decay Tank 13 at 25 psig (2.7 acncsphere), it would

ake approxi=a:ely 40.5 minu:es :o reach :his 3.3 H, concen::a:1:n

~

in the tank,- based on the f ollewing estimate:

100~ (1.4 fc3 H,/ min) = 600s*ca.

"3 (x */ sin) '2. 7 atm)

(cank volume)

= 100* (~ ~ ' e ,3 u"I-) = 1620 f:3 (x %/ min) sin 3 **

x = 0.0864 :/=in increase in :ank .'. 0.086$h/ min W1:h 0 psig (1 a:=) in decay :ank 1: would :ake approx 1=a:ely 3.5

=inutes :o reach a 2% 3 3 ::ncen: ration which is :he presen: Techni-cal Specificacion limit! A: 100 psig in :he :ank, within 60 minu:es

his 2* encen::acion would be reached.

This points :o ei:her a flaw in :he nor:a1 =cdes of cpera:icn of :he WG 3ys:en or, : ore likely, e discrepancy between :he Technical Specification and reasonable 11=1:s for Opera:ing the sys:e= in Mode (3).

n

5) Westinghouse Standard TAchnical Specifica:icns (STS) werd : heir specif t:a: ion for the explosive gas mixture in :he Was:e Oas holdu; sys:em similar :o this:

The concen:;2:ica of oxygen in :he was:e gas holdup sys:em shall be lisi:ed to < 2" by volume.

Note that no sen:icn of hydrogen concentra:icas exis:s in :his sea:enen:.

6) "3efore an explosive mixture can propagate fla:e a porti:n :f :he six:ure =ust be heated to i:s igni: ion :empera:ure."3 The ginimum igni:ica te=pera:ure of hydrogen vapors in Oxygen . s 306 w . .4 The normai operac ng temperature of :he hydrogen rec::biners is appecximacely 350*y. An alarm and corresponding shutd:wn of the oxygen feed to :he hydrogen rece=biner occurs when :he temperature in :he recombiner ca:alys: bed reaches 1050*y. This high :e:pera-ture can be detec:ed by any one or scre of :he six :her cc:uples which are posi:icned at various levels thr:ughou: :he rec :biner

acalyst bed. These :hermoccupies, along _vi:h five others loca:ed at specific poin: be:veen the reco=biner skid inle: and cucle:

valves, are wired :o a char: recorder thereby pr:viding :he :pe:at:r with con:inucus :e:perature monitoring capabiliry. Addi:1cnally,

here are six backup thermocouples already installed in :he ree::-

[ \

biner catalys: bed which can be used in :he event :hac One of. he

\s normally used thermoccupies f ails.

i b

I' s

v) 7) "The usual problem in dealing with ce=bustible mixtures is to con-crol :he atmosphere so tha: the ec= position at all :1=es is cu: side the fla==able range."5 3ecause the Wasta Gas Systa= is designed :o operate wi:hin limi:s :o prevent ce= bus:1ble =1xtures, :he above condition of opersting out-side of the fla=mable range is met. Only if there is a break in the Wasta Gas piping could the potential for an explosive H, - 0, =1x:ure exis: and even : hen :he igni: ion te=pera:ure of 1050 F ius: Se present.

In su==ary, a Technical Specificacica of 13* oxygen ec=centrati:n in :he Was:e Gas holdup system is qui:e conservative, leavnng a 40" margin of error between :his 11=i: and :he limi: of 3* oxygen for nonfla==able oxygen-hydrogen six:ures.

M.oreover, the Waste Gas Sys:s is designed wi:h buil:-in safety shu:dewn features which preven: :he oxygen-hyd:cgen concen::a:1:ns f:c reaching fla==able p;cportions. This is evidenced by ;he fac

ha: :he analy:ers which seasure oxygen inlet and oucle: concentra-ticas ac::ss :he rec:=biner bed possesa f ea:ures which will shu: off

he or/ gen supply to :he sys te= bef ore fla==able oxygen-hyd:: gen concentrations develop. If for some reason the inlet oxygen :encen-

acion to che recombiner reaches 3.3*., he inlet oxygen analy:e:

vill not only close :he oxygen supply valve bu: v111 clase valve IWG3 and LWGli which are :he hyd:cgen purge isola:icn valves f::=

r"'g Uni: I and Uni: Il Volume Con:rol Tanks :espectively.

V The hycrogen analy:ers in :he Waste Gas Sys:e= are also designed wi:h alarm and/or shu:down f aa:ures. The hyd:cgen analy:e which

oni: ors :he inle: hydrogen concen::ation to :he rec:=biner vill

igger an alar = at 6.0% nyd:cgen and snu: off :he oxygen supply ::

he rece biner at concen::scicas of > 9.0" hydrogen. The a:her hydrogen analy:er =enitors :he cencentracion of hydrogen as 1:

leaves :he recombiner and =cdula:es the oxygen addi:1on valve :s maintain p;cper oxygen-hyd:: gen six:ures for safe, au:cca:ic opera-tien.

Inputs :o the Was:e Gas Syste= fr = sources other :han :he 7CT ? urge header have been deter =ined to be of lev enough oxygen or hyd:cgen concentration as to mini =1:e interference with the nc:=al Operation of :he Was:s Gas Syste=. The ?ressu 1:e: Relief Tank appears :o be the source which could cen:ribute :he larges volu=e of gas at :ne

i=e :o :he Waste Gas System; however, :his is cos:ly ni::: gen and shculd only impact the sys:em gas :c:posi: ion for shor: perieds of time, such as during plant s tar:tp .

References

! ?a::y, Frank A. Industrial Hygiene and Toxicology. Volc=e I. Generai

? inciples. Interscienes ?ublishers, Inc. New York. Pgs. 339-540, 2 ibid, P. 533.

3 ibid, P. 324

(~N } ibid, ?. 534 I,v) - ib id / ? . 541.

.>ee , oce a

ML20008E635

Text

Dear Mr. Denton:

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