U-602686, Provides Response to GL 96-06, Assurance of Equipment Operability & Containment Integrity During Design-Basis Accident Conditions

Provides Response to GL 96-06, Assurance of Equipment Operability & Containment Integrity During Design-Basis Accident Conditions

ML20134C480
Person / Time
Site:	Clinton
Issue date:	01/28/1997
From:	Connell W ILLINOIS POWER CO.
To:	NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
References
GL-96-06, GL-96-6, U-602686, WC-078-97, WC-78-97, NUDOCS 9702030109
Download: ML20134C480 (10)

Text

.

l O

liknots Power Company Chnton Power Station l

l P.O. Box 678 Chnton. IL 61727 i Tel 217 935-8881 P9WER Effs" WC-078-97 January 28, 1997 l

Docket No. 50-461 Document Control Desk i Nuclear Regulatory Commission l

Washington, D.C. 20555 '

Subject:

Illinois Power 120-Day Response to Generic Letter (GL) 96-06, " Assurance of Equipment Operability and Containment Integrity During Design-Basis Accident Conditions"  !

l

Dear Sir:

This letter is providing Illinois Power's (IP's) 120-day response to GL 96-06 which requires that addressees determine: 1 (1) if containment air cooler cooling water systems are susceptible to either waterhammer or two-phase flow conditions during postulated accident conditions; 1

(2) if piping systems that penetrate containment are susceptible to thermal expansion of fluid so that overpressurization of piping could occur.

Regarding Issue (1), . g ovided an initial response via letter U-602654 dated '

October 28,1996. Additional discussion relative to Issue (1), based on industry information and discussions with NRC staff, are included in Attachment 2.

Regarding issue (2), IP evaluated all Clinton Power Station (CPS) containment penetrations for susceptibility to overpressurization. From this review, IP identified l twenty-one penetrations as being potentially susceptible. Appropriate actions to assure operability of these penetrations will be completed prior to restart from refueling outage /

6 (RF-6). Details concerning IP action taken to address this susceptibility to overpressurization are included in Attachment 2.

KO I

9702030109 970128?

PDR ADOCK 05000461 P PDR-UdVUJJ

^

\

\

U-602686 Page 2 Attachment 1 provides an affidavit supporting the facts set forth in this letter.

i Sincerely yours, i

J

• i

! Wilfred Connell[g Vice President

! JSP/krk i

) Attachments cc: NRC Clinton Licensing Project Manager NRC Resident Office, V-690 Regional Administrator, Region III, USNRC Illinois Department of Nuclear Safety

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

Attachment 1

, , to U-602686 Richard F. Phares, being first duly sworn, deposes and says: That he is Manager -

Nuclear Assessment at Illinois Power; that this letter supplying information for Generic Letter 96-06 has been prepared under his supervision and direction; that he knows the contents thereof; and that to the best of his knowledge and belief said letter and the facts contained therein are true and correct.

Date: This /7' day ofJanuary 1997.

'/

Signe -

.RichardV. Phares '

STATE OF ILLINOIS ] SS. ,:::::::::::::: :::::::

f l

• OFFICUU SEAL" 3euS* COUNTY J Joosins 8.Masdes Noisy P@go,Suas of Ennis

My CommissionEmpires11/M97 c::::::::::::::::::::::::

Subscribed and sworn to before me this 28 day ofJanuary 1997.

ca Axe 3 k w k &

'g (Notary Pubfic)

Attachment 2

{ , , to U-602686

Page1

The requested actions from Generic Letter (GL) 96-06, along with Illinois Power's

] (IP's) 120-day responses are provided below. Also provided is additional discussion j relative to Issue (1) based on industry information and discussions with NRC staff.

(1) if containment air cooler cooling water systems are susceptibie to either

) waterhammer or two-phase flow conditions during postulated accident i conditions; i Backaround l i

4 In September 1996, the NRC issued GL 96-06, " Assurance ofEquipment

{ Operability and Containment Integrity During Design Basis Accident Conditions."

}

! The following excerpts are from IP's 30-day response to this GL provided in IP j letter U-602654 dated October 28,1996:

1

! CPS does not rely on safety-related coolers for contairanent cooling...

i

! ...It should, however be noted that CPS Emergency Operating Procedure 4402.01

] (EOP-6) allows for the defeating of containment isolation interlocks of the non-  !

safety Drywell Cooling (VP) system and supplemental drywell cooling (WO) if 1 drywell temperature cannot be held below 135 F. The design of the WO and VP j systems are closed loops with compression tanks that maintain a positive pressure in the system. As such, the lines would not drain down causing vapor cavities in

} the piping in containment or drywell. Therefore, waterhammer would not be

postulated to occur in these two systems.

l Emergency Operating Procedures (EOPs) are plant procedures that direct i operators to take actions necessary to mitigate the consequences of transients and

] accidents that have caused plant parameters to exceed reactor protection system setpoints, j engineered safety limit setpoints or other established limits. In some cases, these i procedures may include the use of non-safety systems if there is a reasonable likelihood i that these systems will be both available and of benefit. Use of the non-safety related WO j and VP systems are two such non-safety related systems that meet this criterion

! (reasonable likelihood of availability and of benefit) for drywell cooling, when their j containment isolation interlocks are bypassed. There is no requirement to design non-

! safety systems specified in the EOPs to safety related criteria.

There is a small likelihood that waterhammer of the type described in GL 96-06 may occur when the WO and VP systems are operated as directed by EOP-6. For these phenomena to occur, the system would have to be isolated for a substantial amount of time with the drywell temperature near design bases in order to have significant steam voiding to occur leading to potential wateihammer. Notwithstanding, the waterhammer would most likely dampen out without causing catastrophic failure of any piping or components. Analysis shows that in the unlikely event that a waterhammer were to occur, I

j -

Attachment 2 to U-602686 Page 2 the ability to provide containment isolation and integrity would be maintained. Therefore, the worst possible result would be the inability for WO and VP to perform drywell cooling functions. No credit is taken for these systems to provide drywell cooling during design bases events. Therefore, they do not provide a design basis safety function.

Consequently, EOP guidance allowing the use of these coolers to reduce drywell temperature is appropriate.

Based on the above and the previous CPS response to GL 96-06, Issue (1),  ;

i waterhammer is not an issue at CPS. In addition, two-phase flow effects are not an issue since CPS does not rely on containment coolers to perform design bases safety-related ,

cooling functions. l l

(2) if piping systems that penetrate containment are susceptible to thermal expansion of fluid so that overpressurization of piping could occur.

All containment piping penetrations have been reviewed to determine susceptibility to these phenomena. The list of penetrations reviewed along with justifications for those removed from consideration is provided in Attachment 3. Twenty-one penetrations were identified as being potentially susceptible to these phenomena. The penetrations were .

dispositioned as follows: I Further investigation identified that penetrations IMC-048,204,205, and 208 do not receive isolation signals during a LOCA. These penetrations are for the cooling water supplies to the safety related combustible gas compressor room coolers.

Overpressurization of piping could potentially occur for these penetrations during i smveillance testing if both the inside and outside containment isolation valves were closed at the same time. CPS procedures are being revised to prevent isolation of multiple valves simultaneously, during surveillance testing, thereby eliminating the possibility of the subject scenario. Caution statements and guidance are also being added to the system operating procedures to assure that the phenomena are not inadvertently introduced during maintenance or other system evolutions.

Penetrations IMC-116,078, and 088 are not required post-LOCA or during normal plant operation. These penetrations will be drained prior to restart from the current CPS refueling outage (RF-6) and subsequently will not be susceptible.

The piping for penetrations IMC-056,081,082,052, and 053 was modified to eliminate the overpressurization concern by adding air chambers to the potentially affected piping. These air chambers will provide a compressible volume of air to accommodate the thermal expansion of water. The potential pressure increase will now be limited to that for the compressibility of air which will not be significant.

Therefore, this concern is no longer an issue for these penetraiions.

r

Attachment 2 l

, , to U-602686

! Page 3 Holes were drilled on the inboard disc face side of the inboard flexible wedge

! containment isolation valves (CIV) for penetrations IMC-046, 047, and 085. As the i fluid between the CIVs thermally expands, the outboard face of the inboard disc will be pushed offits seat and the pressure will be relieved throtigh the hole in the opposite j (inboard) disc face before the penetration assembly would be overpressurized.

f -

Analyses for penetrations IMC-050,065,069,070,103, and 104 show the current j measured CIV leakage to be sufficient to prevent overpressurization. Since these j analyses are based on current leakage rates, re-evaluation will be required each time i new leakage data is obtained or if maintenance is performed that could affect the  !

{ leakage rate. To eliminate this need far continued monitoring and reanalyzes, CPS l

will modify these penetrations prior to re-start following refueling outage (RF-7).

i

. In addition to the above actions, relieving devices (e.g., relief valves) were installed 1 2 in non safety piping systems located inside containment that could potentially experience l the subject phenomena. This action serves to eliminate the potential for these phenomena j to affect the safety related containment isolation function for the containment penetrations j of these non-safety related systems.

) Actions described above, required to assure operabuity of the penetrations, will be

' completed prior to restart from our current refueling outage.

1 J

J

)

i f

d i

li V

1

~

, CONTAINMENT PENETRATIONS Attachment 3 Page1 of4 i

PENETRATION

, SYSTE' A DESCRIPTION (REF. USAR Table 3.8-5) JUSTIF; CATION l NUMBER j 1MG-001 i - ~ " ~ ~ Equipment Hatch I 10 l ~~~1MC-002  ; 10 i

~~' -Peisbhhel[6ck i

}

4

~-~1 MC-003 ~i~ Peissnnel L~o~ck

[ 10

-~ MC-004

~

1 1 i i

-~~ Fuel Transfei Tube i 20

) ~~~1 MC-005- MS mat 6Stssid"C"- ~ ~ ~ ~ T ~-'~ ~ 2

-~~~"

~~~1 MC-006~7 ~MS. -~~ MsiriSteini"A" ~2 i -~ MC-007 1 i MS T Msin Steifn "D"~ ~ - - - ~ ~ i 2~

i 1MC-008 j M S~-~I

--~

MsiriStsiin "B"

^-

2 I ~~FW 1MC-009 i i Fssdwstsi"A" I 3 l ~~~~1 MC-Oi 0 i FW i Fesdwater "B"'

~

l 3 i 1 i RHR PJmpS6ctid5 "A"  ! '4  !

l -~ 1 MC-011~f-~~RH

~~ MC-012 '-~- RH I~ RHR Purhp Sectio 6"B"' -" 4 ,

1 -~ MC-013 1 I RH ~N-' ~ --RHR Puinp SJcti65 "C" 1 4

~1 MC-014 ~I

-~

RH -~I~ _ . - RHR Sh'utdoTJd S6ction "- ~ ~ 5- ~ - ' . . .

- -. . . p g ---. -p _.. - - - -

RHR

~~

! 1MC-016 l RHR LPCi "B"~ ~ ~ ~ ~ ~ ~ ~ ~ ~ - ~ ~ ~12 I i ~-~~~i M C-017 ' i-RH 4

-~ HR R LPCI "C" I 1'-

i 1MC-018 I-~~~~ RH  ; RHR Test tiSEpp.~ "A"' ~ ~ ~ I 7

~1MC-019 ~T R H "-~' RHR Tesit6 SUpf"C" 7 12 i

~

l ~~ MC-0201 .

RH~ -RHR Test t6S6pf"B" 7 '

, -~ MC-021' 1 -~ ~ RH i RHR "A" P.R.V l'~ 7'-

-~ MC-023 1MC-022 i 1; Spsre~ I' 6

--~ RH R "A" P.R.Vi~~-~--

l 1 1 ~~~~ RH Y 7

~

1MC-024 ~T RH I RHR *A"P.R.Vl- 7

} ^ ' 1MC;025 T~ ~ RH ~

~ ~~RHR *B" P.R.Vf(Pursp SuctI6n)' -I- --~~7'-~~ ,

j -1MC-026 i RH ~  !~ RHR "B" P.R.V.'(Heat Exchanger) '~~7 '~ ~~~-

RH--'T-

] ~1 MC-027~  ;

'I 7 '

~~' RHR "B" P.R.V.-(Shutdovii6 Return)

-~~1 MC-028 ~~ *- ~ ~ RI ~RCIC PumiSuction -~T 4 l

1 -1 MC-029-~I---- ~ RH i RHR "C" P.R.V. (Pus'FSJc~ tion) ~~~~~ ~ 7

~ RH~-b~'-

~

RHR "C" P.RN.~(Pdmp Dischafge)~~ 7 i ~

~1MC2031-~~P'-~~RH~~~T~ ~~~-~ RHR'"B" P.R.V.~(Crdsstie to RCIC)' , 7 " ~- 1 l ~~ MC-0321 i LP~~~ 7 -- -~LPCS Purnp Suction 4 H P 7 ~~~-~

~

~ - ~ ~ ~ ~-

I -~~1MC-033 HPCS Test to'Supp.

4 7

i

~1MC ~034 ~'[~~~ SF

-~

~SEppress~i6n Pool C16an ~Up i 4 1MC-035^-~ HPCS Pdinp Dischsig~e--~~~ 1

~

1 HP  : 1

-- ~ ~~

-M-~~ ~ i - ~~~1

~

1 MC-036 ~ I -~~~ LP LPCS PJinpDisc6arge l

I-~ ~

-- ~~

~ ~~ i MC-037 T~~ ~~H P -

HPCS Pump Suction i 4 4 1MC-038-~~l LP i- -~ LPCS P.RN.~(Pump DischaFge)~ ~~ < 7'

~- "

~ ~

1MC-039  ! Spate 7 6 - ~'- ~

~ RI

~~

3

-~~ 1MC-040 RCIC Mint Flow -

I -~ ~ ~ ~ 7 MC-041~ ~RI~ l~-~~'~

1

~ ~ - -RCIC TUrbiris Steam Exh'st.~ ~~ ~~-~ ~ 8 -~ i

~~~~ MC-042~~~"~~-~ ~ Rl "~ 7 1 RCIC Hesd Spray ~i~ ~ ~ ~ ~

i j

--~1MC-043 RI ~~ T

~RCIC TJrbinFStsam Supply ~

~7- ~ 8~

I ~~RCIC TUrbi66 Vacuum breaker ~~I-~~-'~9'~~~~~~~

~1MC-045 .

MS i Main Steam Drain '

14 j 1MC 046~~I- CC CC Supply 22

~ ~

1MC-047'-~I CC  ! CC Return i 22

! 1MC-048 SX 19 i l SX Service Water Supply j

~~~1MC-049~~~i---"~ RA' i ~ Bfeathing Air ' ~ I 10- - -^

1MC-050 i MC Make-up~ Condensate (MC)  ! 23

--"1 MC-051 Spare ~ ~ ~ -

~~~~ 6 ~~-

1MC-052 FC _._.l _ _ _.-_ FueiPooi~Cooisj& Cieanup~-' -- - _ . - - - 21

-p ^ ~ ~ ~ ~ ~ ~

~~~

~~~'1 MC-054-" ~ ~ ' ~ ~- T ~~- ~ ~ ~~~ ~ ~~ S pa'r e

~ ~ ~ ~ ~

~6~ ~~ ~

1MC-055 ~ ~ -- - ~~ S paie ~~ ~ ~ - ~ ~~

~ ~

~

-6 1MC-056 '

FP F P. ContAnrnent StanUipe 21

i CONTAINMENT PENETRATIONS Attachment 3 Page 2 0f 4

\

" ^ " SYSTEM NU BE DESCRIPTION (REF. USAR Table 3.8-5) JUSTIFICATION 1MC-057 IA Instrument Air 10

' ~- ~~ ' ~

10 ' ~~

~

' - - 1 MC-058 ' IA ~ Instrument Booster Air

~ ~ ~ ~ ~ - ~ ~ ' ~ ~ ~

~ ~ ~ ~ ~ ~ ~ ~

~ ~1 MC-059' ~ '

~

< ~SA' Serv'ce i Air ~ ~ 10~

_ 1 MC-060_ ,

RT _ ,_____ _ _ _ _ _ RWCU Pu.mp Supply _ _ __ , .__17 . __ __

1MC-061 . _. . RT . . _ _ . _ . __ RWCU Pump Return - - _ _ _ . - . _- _ 17 _ . _

__,[~

~

~. _15)) _

[1MC.063(( ~~.RD .

.RT _ y __ _ _ _] _ . .C.R'D[ RWCU Pump Dsc6arge))[_~ _ __17_.

_ __1 MC-064 ___ _ _

to_RHR Retum _ __ _ , _ __ l 1MC-065 WX Radwaste Repro. & Disposal ~ ~ ~ ~

23 l 1MC-066 " Spare 6

~~

l iMC-067 - SA~ 10 1

~~ 1MC-068 ~ ~ ~ ~ PS ~ ~ ~ ~ ~ ~' Containrnent PS CNTM ATMOS SA (Cnmt. ~" Press)~

~ ~10 - ~~ ~~-~

[RE l ,1,[ ~~ _ Co' CEquipme_nt'Dra_inslRE li_. [ [ 23} ][_'

~~

]1MC-069] n l

~1MC-070 RF Containment Floor Drains RF l

~~~~ Hydrogen Recombiner from Cont.~' ~ -' 10 ~ ~ ~ ~23~ ~ ~ ~ ~

~

~

1MC-071 ~ ~~ HG'~~~'~~ ~ ~ ' ' ~ ~ ~

~ 1MC-072 ~ ~HG ~ ~ - ' ~ ~ ~ ~ ~ Hydrogen Recombiner to Contnt. ~ ~ ~ ~ ~

10 ~~~~

~~1MC-073 ~ - . . ---_ _ _,_ _ . _ _ _ _ . - -

Spare ' ~~ ~ ~ ~ ~ ~ ~ ~ ".

~~ 6 ~ ~ ~ ~ ,

" ~

~ ~ ~1MC-076 ~ '~ RH

~ ~~

^~~ ~ '- ~~~ ~~~

^ ' RHR P.R.V.~ (Drain) 7

~~1MC-077 ~ Spare " 6 ~ --

~ ~ ~ ~

1MC-078 ~CC ~~ ~'~ ~~

~ ~ ~Corriponent Cooling Water ~ 18

~ ~ ' ~ ~ ~ ~ ~ ~

~ ~ ~1MC-079 SF' ' Suppression Pool Clear.-Up- 4

~~

~ ~ ~1MC-080

.~'.~ ~~.

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

~ ~~~~ ~ ~ ~ ~ Spare ~ - ~ ~ ' _ ' ~ ~ ~_ _ . _ -.

~ 6 ~~

~'

-1MC-083 ' ^ 6 ~~~

~ ~ ~ ~ ~ ~

~ Spare ~ ~ ~~ ~ ~~~

~ ~ ~1MC-084 ~ Spare 6

[~ 1MC-085[ '_ f CY ~ _

Cycle Condensate __

22 f

~ ~ ~1MC-086 ~ RT ~~ ~ ~~RWCU to Condenser ~ ~ ~ ~' ~

17 _ __

1MC-087 RH~~ RHR "A" P.R.V. 7

• ~

~]1 M C-088'_ } [CC . CCW Return ]~__~ _ 16 i _ _ _

- 1MC-089^ ~RH ~ ~

RHR Ht. Exch. Shell Vent 18 1MC-101 . .

VR _ _ . - .

Cont Vent Air Supply ' 10 ,

p

~ ~ ~

- .__ 1 M C-103[____ WO _

Cont. Cooling C_ hilled Water Supp. [ ~ . _23[ _ _  !

~-1MC-104 ~

WO

~ - ~

Cont. Cooling Chilled Water Return ~~ ~

~

23 I 1MC-105- ~ *~

~ Spare ~6

~ 1MC-106 'VR~ ~ Continuous Cnmt. Purge' Air Exh.~ ~' ~ ~

~ '10

[1MC-107 ~ ~ ~ _ VF ._ } [Dryvd!! Cocling Water Supp. __ _ _ 12

_. 1MC 108 VP_ . Drywell Cooling Water retum. ,

12

_1MC _109 _ VP _ _ , _ _ . _

. Drywell Cooling Water Supp. __ _ _,

12

~1 MC-110'~ VP ~~ '

' Drywell Cooling Water retum.

~ ~ ~

12 1MC-111 Spare 6 j

~~ ~ ' ~~ ' ~

~ - ~ 1MC-112 ~

• __. - . . . .'--- Spare ~ 6 i p

~~ ~~ '~ -~ -~ ~

~ " 1 M C-114~

^

~ Spare ~ ~ ~ ~

6' j

--1MC-115 ~ Spare 6 I

~1 MC-116' ' ~ SC ~ ~ ~ ' ~ '

Standby Liquid Control ~ 16 1MC-150~ CM ~ Cnmt. Pressure Monitors 10 1MC1151~

CM ~~ Cnmt. Pressure Monitors 10

~ 1MC-152

'CM Containment Monitoring 10

~~ '1MC-153 CM Drywell Prsssure

~

10

~ ~' iMC-154 ' ~ ~ ~ Spare ' 6 1MC-155 spare 6 1MC-156 VG Conmnt. Pressure (SGTS Train A) 10

~

l -

CONTAINMENT PENETRATIONS Attachment 3 l .

, , Page 3 of 4 1

PENETRATION ' , i SYSTEM DESCRIPTION (REF. USAR Table 3.8-5) JUSTIFICATION l NUMBER ~

1MC-157 CM , Suppression Pool Water Level . 13 1 1MC-158 T- ~ Spsie '~~ ~~~~ -~'"~~~~ T ~~6

! 1 MC-159~ i

~

l Spafe i ~ ~~ 6 1MC-160 ~C CM ~~~~ ~

T~~~-~ ~~~Contbinhient M6nst5risg Sistem ~~10~

~~~1MC-161~~~I 7 ~ ~ ~ ~ Spare T~~~ ~ ~~~6

~

^1MC-162 i-

~

l . Spare  ! 6- ~ ~ ~

~~ 1MC-163~ ! -~~ ~ i- ~~~ Spare i 6

~~1MC~164 { SiA ~M Suppression P6ol Msk~eup  ; 13 '

--1 mci 165 i VIf~~~~~I C5niainment Diffeiential Pressure '-~~ ~10 j -1MC-136 >

HT T- Hydrogsn Redombinsf fr6m Coinnt

~ ~ ~ - ~ ~ ~ ~ ~ ~ ~ ~

10

~

1MC-167 i \lG F~~~ Continnt Pissiuri(SGTS Tiain~B) 10~

q

~

1 MC-168

1MC-169 I

! W(M ~-~[~-- ~-~~~C5ntiinnient Differential Pressure Contmnt. Purge Damper Control L 10~

10

~

1MC-170  ! i Spare 1 6'~ l l 1 MC-171~ T ~ SM l~ Suppissifo~ rip 661 M5keup i 13' 4 1MC-172 i R A' ~ i RHR Ht. Exch. Shell Vent 18

{ ~~~1MC-173-~ ~i ~C M ~~T Contsinment Monitoring Systim i ~10 2

~

~ Spaie- ~ "- ~

1MC-174-~i-~ ~~ --~ ~ ' ~ ~~ i -

6

~~ MCa175 1 i - ~~~-~i- Spsre ~~i 6

-1 MC-176

~

Spire i 6-T~ ~p~ ~~' ]~~~~_ _ . -Supf Pod!Watei Level (RCIC)~~

~

~

13 4 1 l i Spare -~~~~~i 6~ ~ ~ ~ ~ ~ ~

~~~ MC~178 g ..THP SM T H PTCore Spray SyEtsii& Suppression 13' -'~~~-Pool Malis-Up .

. ~ ~~~- ~~~ H.P.~ SUP.~ Pool LEVEL ~~

~

__^~1 C2180~ I HP' . 13 ~~~

~

iMC-181 ~~SM ~ I SUff P6ol Watirl~e~ vel i 13- - ~ ~

j ~~~1mci 182  ; --~I ~ - ~-~ ~ ~ ~ ~ ~~ Sparo~ ~

7- ~~~ ~ 6- ~ ~ -

~ ~ ~ ~1MC-183 l ~ ' ~ ~CM i Supp.~ P6ol Watei Level ~ -~ ~ ~~~~ ~R ~~ ~~~ 13- ~ ~ ~ - ~ ~

! 1MC-184-~1 7~~ ~ Spare ~

i 6

, 1MC-200~ -

1 RI I~ ~~ ~ SEpf Pool Wateil.svel(RCIC)- ~l~~-~ ~ 13 i -

~ 1 MC-201 T--~~~T- ~ ~ ~ ~~ " ~ ~ -~ Spare i 6'~~~~~~

1MC;202^ "~~

Spire  ; 6~

~

~~

4 ~~~1 MC-2037~ ~CM' Cintsihrhent Monitoring i ~ --~10~

~~~1MC'204~~

SX  : S/D Service Water s 19 1 1MC-205 -

SX S/D Service Water 19 i 1MC-206 i-~~ lA-~-~ T------ ~~~ ~ lristiurri6nt Ali i 10

" MC;207 ~7

~ ~

i 1 ~~-~ ~I ~ ~ ~ Spare '

6 --~-~

I

-1MCZ208 i SX S/D Service Water Return -

'-~~ - - ~~~

19

~~1MC-209 i

- ~~~~ ~~ ~ ~ Sl5are ~ ~~~ 6 I ~ ~~1 MC-210 PS

~ ~ ~ Post'AccideWSample 10 l 1MC-211-i--~~~~ Sphie~ ~

~ ~ - ~

6- ~ ~ - -

I i

. ~- . - - -. .

JUSTIFICATION CODES FOR THERMAL Attachment 3

, . . PRESSURIZATION Page 4 of 4 1 ECCS - check valve will allow expanding trapped fluid out.

2 MSIV, steam N/A.

3 FW containment penetration has check valves that will allow expansion.

4 Suppression pool suction. No inboard isolation. Open ended to pool.

5 Check valve IE12-F475 provides relief of bottled up fluid.

6 Spare.

7 Suppression pool line. No inboard isolation. Open ended to pool.

8 Steam line. Not water filled.

9 Vacuum breaker line. Not water filled.

10 Not water filled.

I1 Temporary penetration. Used oniv for decon.

12 Relief valve is installed between iv.ation valves.

13 Pool level monitoring -No inboard isolation. Open ended to pool.

14 If line contains water it will be a hot water steam mixture. Line will cool after a trip so overpressure due to thermal expansion of water is not an issue. I 15 Outboard isolation valve is a check valve and there is a relief valve downstream ofit.

16 Penetration drained. See Attachment 2, page 2 for additional discussion 17 RWCU is at high temperature and pressure during operation. It serves no safety function.

Line will cool after a trip so cverpressure due to thermal expansion is not an issue.

18 Line abandoned and blind coupling installed per RH-33. Line not water filled.

19 Valves not closed post LOCA. Surveillance's modified to cycle one valve at a time.

20 Not water filled during normal operation.

21 Air chambers added. See Attachment 2, page 2 for additional discussion 22 Holes drilled in disc. See Attachment 2, page 3 for additional discussion 23 Leakage is sufficient to prevent overpressure. See Attachment 2, page 3 for additional discussion j i

J