ML20085M916

Second Interim Deficiency Rept Re Control Logic Problem W/Hpci & RCIC Sys.Initially Reported on 731110.Peak Clad Temp Well Below Perforation Threshold.Final Rept Will Be Submitted by 740110

ML20085M916
Person / Time
Site:	Browns Ferry
Issue date:	12/14/1973
From:	Gilleland J TENNESSEE VALLEY AUTHORITY
To:	Kruesi F US ATOMIC ENERGY COMMISSION (AEC)
Shared Package
ML20085M910	List: ML20085M907 ML20085M913 ML20085M916 ML20085N400
References
10CFR-050.55E, 10CFR-50.55E, NUDOCS 8311090458
Download: ML20085M916 (5)

Text

. _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _

i  !

c

.N '

r

" TENNESSEE VALLEY AL THORITY ,

CHA1TANDOGA, TENNESSEE  !

, 37401 ,

December 14, 1973 40

$$$3 f

I Mr. F. E. Krucsi, Director Directorate of Regulatory Operations U.S. Atomic Energy Commission Washington, DC 20545 l

Dear Mr. Kruesi:

TVA made initial report to AEC-DRO Region II on November 10, 1973, l of a possible design deficiency in the control logic of HPCI and RCIC systems of our Browns Ferry Nuclear Plant. An interim report on this deficiency was submitted to you on December 10, 1973. En- I closed is a second interim report on the safety implications I associated with this problem. We will submit a final report by January 10, 1974, on design changes being made.

Vo truly yours, J. E. Gilleland 'h.. .

Assistant to the Manager of Power I l

Enclosure CC (Enclosure):

Mr. Norman C. Moseley, Director Directorate of Regulatory Operations U.S. Atomic Energy Commission Region II - Suite 818 230 Peachtree Street, W.

Atlanta, Georgia 30303 i

y f'v,g \'s , o f, .

B311090458 74071o

~'

O 1,C) pDR ADOCK 05000260 g fr j PDR h

_ _ - - _ _ _ _ _ - -_ ___- --__N

l .

O O '

ENCWSURE -

! BROWNS FERRY NUCLEAR PLANT UNITS 2 AND 3 l HPCI AND RCIC CONTROL IAGIC PROBLEM l

INTERIM REPORT 1

i i

References (1) Letter from E. F. Thomas to John F. O' Leary, AEC, Director, the Directorate of Licensing, Office of Regulation, " Tennessee Valley Authority - Browns Ferry Nuclear Plant Unit 1 - Docket .

j No. 50-259 - Facility Operating License DPR Abnormal Occurrence Report BFAO - 7334W," with enclosure, dated November 19, 1973. ,

l (2) Letter from R. B. Beers to H. M. Bankus, General Electric l Company Internal Letter No. 4668, " Pipe Break Outside Contain-4 r ment: Main Steam Line Break No RCIC, No HPCI, No Loss of Offsite Power," with attachment, dated June 1, 1973. Copy-is attached.

The initial report of the HPCI (High Pressure Coolant Injection) and RCIC (Beactor Core Isolation Cooling) control logic problem of units 2 and 3 at:the Browns .

Ferry Nuclear Plant was made on November'10, 1973, to the AEC Directorate of Reigulatory Operations, Region II Office in compliance with paragraph 50.55(e)' ,

of 10CFR50.

f Under the operating situation described in reference 1 for the unit 1 reactor,'

the momentary loss of'offsite power would trip the Feedwater Control. System.

(PC3) as well as:the HPCI and RCIC systems. - The operator would have been

. unable to start the RCIC and HPCI systems until the standby diesel'gsneratore .

- energized-the shutdown auxiliary boards and the tripping logic.to.the-RCICl and HPCI systems was manually reset. Since units 2 and.3 of the plant-are:

' designed similarly to unit 1, we assume that similar occurrences can later take place when units 2 and 3 are operated unless appropriate changes'are made.. ,

' The safety implications associated with'thi's problem would be no= worse than~

, - those produced during the situation described 11a reference 2-(copy. attached).

• even if the plant had been at full power and_had contained an' equilibrium

- inventory of fission products., The1 situation in reference 2 assumed'a usin a

L -

+ _ __,-_

/

. . (mJ t ,

steam line break with no RCIC, no HPCI, and no loss of offsite power. A main steam line break causes closure of the main steam line isolation valves; a loss of offsite power causes isolation of the steam lines by either rapid closure of the steam turbine control valves or by closure of the turbine stop valves. There would be no steam dump with no offsite power. Thus, either dituation isolates the steam lines and requires steam relief to the torus. The curves in reference 2 show that the reactor is safe for 10 minutes with no steam flow except through the relief valves and no RCIC or HPCI. The presence or lack of offsite power during this time interval would not affect the results. Note in reference 2 that after 10 minutes the Automatic Depressuri-zation system (ADS) was actuated by operator action. It could also be assumed that, had it been necessary during the present problem, the ADS could have been manually actuated after 10 minutes. Also note in the curves in reference 2 that the vessel pressure did not exceed 1080 psia, the peak clad temperature did not exceed 1200'F, and an adequate vessel water level was maintained.

l l

l I

r

) (]

j CEllER AL [, . 21.ECT(]

li ATOMIC POWER EQUIP:!EilT LEPARTMEllT h

San Jose, California i

Internal Letter !!o. 4658 cc: RR Barris y JE Stice a June 1,1973 BN Rogers -

1, :

H. H. Bankus g Knoxville Office MAlli STEAt-lLIllE BREAK, H0 RCIC, t.

Subject:

PIPE BREAK OUTSIDE C0itTAlllMEliT:

' NO HPCI,i!0 LOSS OF 0FFSITE POWER Recently TVA (Jerry Chapman) has postulated a stes.11in; break in the steam tunnel which disables the RCIC. They also assumed a single failure of the HPCI with offsite power available and drywell coolers opercting. ,5 4

Design Engineering hi s reviewed the case of a steamline breck outside the .

containment with no RCIC, no HPCI, no loss of offsite power and drywell

• coolers operating for a 251-764 '67 product line plant. They have concluded -

that the peak clad temperature is well below the perforation threshold and i no fuel rod failures will occur. Adequate water le/e1 is maintained and 10 minutes following the accident the operator.is assumed to take action by . ,

I

manually activating the ADS system. ,

Please informally advise TVA (Jerry Chapman) of this fact, t ke. - -

5 Acting llanager Browns Ferry Project .- .

kn h

- - a w ., a , ,, .

K!!DNILLEOFFIC2 .

n v

' -u .. . - - . ~ ., . . . -M . w .

.f.g p , . :, ~ . , ,, --- ..:' - ;

~ . p r~) , . .. . ;' .. .- (

, q{ o y o ~~,.~~ - pyyj

. . . "..:I..:::

t. .:.... . . ' .u

.. . s. m. s :  ;-

..: . " t .-. .. i.

0 O

o s G

o.

., g 'g.,, j g g , . n, g-i i s , - -

. . ; .3.g.. ! ... . l . .... .... ; . . .y .

i (

. . . t o . : . . . ur o ... ,

1 o g $y o ::.

<. i w o .

. . .o e poo. n

...1/,.*.

+.. . . i. . . . .. . a i-. . .. . e. . .

~

i

, a

. .i . , :.l e. . . 1 . . .im.. . : p. ..

..I.... .,. . -

. i !. . . .; . N .

li. . . .

a. ,

y u.,.

. . . .m t. .. , ........l.:..;:...:....,l.....:.., . g .. ,

.j,

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

.g.. . n .- o: .: . . .;

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

,......,...t. o,.: _p.

, . . . . ...1 . . . .

I 1, .

t

y. v. .

1..

.........l.... i

.n

o. . ,..; . . .

...!e

. i.

.1 . ., . 6, . .! . .

, c

.: O;*

qm i i- . . f .

..9.. .

.}

. ... ..,.! . . . } - - -

l- '.;- .

4t.

. .. .h , Z .L .~..ee  !

.. ..', O '. ;.2 : .jg .  :... ..., , e

-.1

.)...

.- c.r-a:. . .:  :

j ..

I . .;. . .. i. . .L . ~ * . kl:~ 2 * .j ' <

. . i._. .

o.. . .,

. . l. . ., l . f .:.,;.i. u  :. ....

o ....i c-7 u .. .. o% . . .

. w .c..

.;m.-.........

c  :.;g: . . ..

p .

. o..,a O l' o; -

1..i ,.- . ! '-.[ n,8 .. .e: !.-

i I...e/. 3

... ~

o' ..:...

r .. : h y ivlz ,;..L 4... m i M;ni:.' ait

" - i H. ..

p., o .." [. ..'. l.. .f.f.i: ~ ,- . .__ I.... . . T.. . . : .g-n.. .., . . . . s. . : I

o.  !. . .. ... ,o , .8 . , . , .. . . T. ."..,J .-

~.; 3 ,;

.L.: e  :

. i j ;:

. g b..  :.. } e i l 4 - ,

. . ., c.;}s

~~,:  :.

ir: . C g . .l c.;. ., ., ,1C gy;. ..

..(, -l ..

e .' -l *

• ~1 l . : M o.O

, " - ]b'- .

. t ,r -..'....i.

N. ..;: 1 8 r -

. -(i. c<;

. . .... . . . C'. : L. .

....o.. .. .l... . . =

.i gjj .t11.. .

i j ... . , .f..

.,....s . .: .. v .... .l

.. v..

e

.s.

gA.

.- -. .O g%,

W.m 1 s,

,l . . , .. : . 8 .g. ;G l $:

q: ,4 ,

,,e 9, 1

.- ' ' ~ ~

! y' e . ; e

".9 .. . w.n.. .., . .. c.y .. . u. r ... q <.. . . o ct.. .. . . :.iE. O.".~] ~;'o.e. ~ ' I ".,. p'. **:'".

' ., .:'.l.  :'. l. .~g" .". .'.~ ~~,I ~..<.. 1.s' , "' '

. ) '.'. '. P.. g* . .. .

s...

. s.

gl./.T. !.d ;.t. Er.J Ji . / p.

h..j;

. F . .'.

[,...-!,.. . ;. 's I..g ' ,. .l. j

• o -..

3.. Q --. -l3 ..:t..- . : .-  : ; , - "-l .. Ki. t t .r:.: - q" I . . .. :. -

. 12 s.: . . . . . . . ;.

., .O . Q,. l... .r l ..

. . ' g :.. .?

.' ,- .W g f r .s&.

., .j ge, s$! . ..W;.- . C. .g . c.4 **'.;.

1

. . . s. . 7. f -

• g

} . I.

. : :. . . .. . . . .I . . .. . g . 3 . ,

i e t.-

l  ;

C ' .. : c:,n...t~1 1 _;. ' 1 : ...: O .. g :.i. e.: i../.ge.

.J . O .!s-.. . . - , , . . . . . g. . . i :

i I. h. .g......J...

• : .~ . :..;...

x. ..lo., i ..

. a. 1 . . O .. t.,f*,,- 8 ' . :l .

. . . r r.. . ._..s,.. s . . .. n

.\tt.e.:s..

.>.. ; u, . ..-og -+.

.. ".a .

..  :,s  :

. . _e. .l _ ..

. W. -

. .. W.  : _. L;- n: : s...

.I . .........g....

l. g -

,y o .. ,,,j . ..

..o.2 g .

.. t :. i. .:) vy....g . ; .p : ; .- ., ) .; . . p;.., . ..

e.!

W. . :;.. p .. 07. . y t[t * .:  :. - l.

g:. 13 ,.;.[. .. .

g . : ..

j.

Q .,;.,. y. .. '

g .. .....W. , . p. . ..a. }:.p..,.,,.y

.. g . t. t .

' .:4.

h.. ..a ~. c_ *. ' ' s}: i' . W

.E .d. . ; . ; .

o

. p c:,. s.

+

.. .'. l . . 5.. . .

'O.3.

v. s t.'l

...i

. 'g .:..";

t ..'..  ;.. - [ .i:. ". 8 .,

., 8 8 O  ; g. i . .n

d. , CL 6gy .

p. .~.Q.. .2 -:_: .

.s , j .. .. .

4

.e. . .. i . ): ..L. s. l ....

. . . Li. ..- ,, n..r.i::j :

. b.a .. .. . . I -

o.. r: . .

. e ]lf . . ".U Wa . . -... . . . j. . . -

. .e a

.- e i, ..

. 8

. .i. ..':

.'.  ; & 8 J. 4

..,....~.,.:..., .w .'- .s..;,. ,s..v.

. . . u,a.

, - :r .: . . - . . . . . . , .

EC :.g ,

. . , .. . , . . , ~ . .:.- ... . . ....... . 2..g. $

i;.w...u:.,4, ...,.. p .

+ . . .p. w , , ......... .........:- l.. . .

• .g. , ,..

. .. i.:.: p., . t ..:n. ..c. }.; ..a. ..'.m.m. . s.... . . . . _. . . .. m.

.. y cw

. 1. .

..s.

.= =. - .a. . . .. . . . . . . .m i .,..i. .. ... . g. .. t.

4. P ..A 4.4.4 p . ..wt. n.a .arpjA..:.=g,.m. .r,.:.;;.#,.: .. .g::. .

At I ,

b. [* p .} / a .- .. J.".1 _ F.

[ . . - - ... . . . . 4i f,.3. * .u;. ., q m. . .. . h. . . . . ,,,,g f.i ,

a j 4 e t- . . . .

t* -

I,M, #y

,...1.... ."f. {,, . .} . k"

• I. .... /J . . . . . .a . g . . >. s . .

e  :-

1 d- J. . . . . .. . .!.*

• l .

.i 6 t .- .

', Q - .. 1 W- . ..

2 . : . s. . . . . . . . . . . , Q .. . { . - l

{

, .. . ... . :. ,. ..a . . ., t. . .I.- . .

i ,> . - n i -

. . 2,.. .. .

4"--'- *?": I-.*J .t . . .p. ..i.s- . . . . . . . ii . . . . .,

m. . . .e. . ..

....,.... ... . . . n : p.. t de f ;- T*.-  :- --7:ns k,..,',*p I

..,.-,.a..  !---.

w .s

• 4.w ,*. .. . i _ _ _ r _.; .f. . . .

e g. . . , , t .

g e p. . . .,. ~,*. .. ..- . . ...

4 , - .7 ..[ .

s

. . . . , , . g.. ......g.u ,a.L _. a

,. . 1

..g.. . -g  :. .g g ,. ,. .. ... g.

m :.

s.

1-.~*,..

i;/.] . ; .

3 \ .:. ..s....,..

. C'. C.'

4, i .. . . . . . ,..4...

1. . .

..t . 1

'. ) 4  ; -

.- . . O ! .* .I #

-- {,j n .:;:l' .r_ .. ;; .. : :j. . . ~

--. , . : M .y

• j . ..: H ,~ti 8se. i.y.{. . ' . g v - .*.' ; . . . ~ . .O ,q 4: .. j .

. . ...:, . - . / ; "; ..L . -

s. , p..

. ,,: :..~.,i ct;..il,_.i p...........i. . i tc,, t "p.;..

ct .! - . .

t

_._ . . .M, .,  ; 1 i I . .;

i, .. ;.

~~

J

. 1; ..' . .+

' ...... .**. , .,.i . r.... : ..' . l,

. .. ,~ . : LLI .. 1 l' .3* S ' .. .: '

. , . . ..., .. .: F. . . . ..a... L i ;.. .l

.o , . .:

i.. . . .

.. ,.. .;  ; . i . ..: . $su t ..\.i... .. ..

.1,t . i . . . , . :._

e ,

. . . . g .m . .. ..g. .:. .

) . . . .

m

...g ....

/._i .

. .; ,g i

s4',.,:

i

(. ,A.

...  ; . . . . . ...., .o.:

i. .';

. :: . .  ;. .l . . ; 'k . .

g. . l

. . .l. -

44 m.e

~

!- .t 9- * . . . . ..j .

l J- A,2 . [. ' ; ; 't

. ,: . ._ 4 . .e.::.l m f.*; a.:.

t  !

i.......,.~..

.l . D l ...l,. . 1. [.

. ' .:,-. . . . . . A . 3 Io'I N g,,d t' -

, ; l . ; :. ,

............;...,.)..,,

g . n  :.

.g - . 1.

i

g 7, y,

r. t

...t...

.:. 1... . e "t ...

'.. .g. :. 4.s,

- p. g. .l .

} ,

O u E ,t ,

.,E.

. _ I.. ;,.. ..... ,.

. .vv . . . d.: 7. . ' . , .; . .

~

. . . u to ;s: .

' 9: . .

W

~ .. ,: -

.,a,. ......,....:  :-- a f..~ l -

. .l ..

. \ .\ . .cJ. e%

,. ., . .. l. ... . g. .... ..

_.  : o .. g . . .

.,...i,,. % .

b 1

, . ..g. . ) . , .

t-

....y.....

g.

.)g , .i. ..,,,

. . ,O,,, . . g'

.s .

%r. .c. .: .l...,

,. I, . . . , .. .

.f . . >

.+

4 l

.g

. .g... .

El e

.t

.., . .e r' ;

A

. . ..I .. . . i w

• E.'I- l .. . - f% . .

.......i...-.r...

. I  !

o. .

O a o o.

o O -

!'.o

.. . ., . .l; . e .:.- .: q l '  : i s

l 3.; . ..;.

. %o  :. . .o o. .o

..t. :. .: .... .T. g ., p .. a .j.... . / ..o. , i. ,l, , ,,, t.g

. - C g, . . . .m. ,g a. . ..

,. . . . .T ,,-

W .. : g. . , ,,, . 6, e .

.L

~

f' c TENNESSEE VALLEY AlsTHORITY CHATTANOOGA, TENNESSEE 37401 Deeember 10, 1973 40

$${f,0j l

$0 '$ $~]

Mr. F. E. Kruesi, Director -#6d Directorate of Regulatory Operations - j_1 (f U.S. Atomic Energy Commission Washington, DC 20545

Dear Mr. Kruesi:

In conformance with paragraph 50 55(e) of 10 CFR 50, this is submitted as an interim report on a design deficiency in the control logic of HPCI and RCIC systems of our Browns Ferry Nuclear Plant units 2 and 3. Initial report of this deficiency was made to AEC<-DRO Region II on November 10, 1973. Had this deficiency not been discovered, a complete loss of plant electrical power would have caused the HPCI and RCIC to be inoperable until manually reset.

We are continuing to analyze the safety implications associated with this problem and we are making design changes to these control systems. We vill supply a final report on this problem to you by January 10, 1974.

Very truly yours, A+

J. E. Gilleland Assistant to the Manager of Power CC: Mr. Norman C. Moseley, Director Directorate of Regulatory Operations U.S. Atomic Energy Commission Region II-- Suite 818 l 230 Peachtree Street, HW. j' Atlanta, Georgia 30303 i

gf {

1\ (

W o o, 2 -.

Y)f)q v e le t '

L