ML19354D431

Responds to Generic Ltr 89-16 Re Installation of Hardened Wetwell Vent.Hardened Vent Will Be Installed in Unit 2 During Next Refueling Outage & Before Restart for Units 1 & 3

ML19354D431
Person / Time
Site:	Browns Ferry
Issue date:	10/30/1989
From:	Michael Ray TENNESSEE VALLEY AUTHORITY
To:	NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
References
GL-89-16, NUDOCS 8911090005
Download: ML19354D431 (3)

Text

r -- :

p: ,

a

> 'l TENNESSEE VALLEY AUTHORITY j CH ATTANOOGA, TENNES$EE 37401 SN 1578 Lookout Place OCT 5 01989 U.S. Nuclear Regulatory Commitsion I

ATTN: Document Control Desk o Washington, D.C. '20555  ;

Gentlemen:

In the Matter of- ) Docket Nos. 50-259 Tennessee Valley Authority ) 50-260  :

50-296 BROWNS FERRY NUCLEAR PLANT (BFN) - RESPONSE TO GENERIC LETTER (GL) 89-16

' INSTALLATION OF HARDENED HETHELL VENT" On September 1, 1989,'the NRC issued Generic Letter 89-16 to inform the owners

.of Bolling Water Reactor (BHR) plants with Mark I containments of the NRC

• program for disposition of the issues related to the Mark I Containment Performance Improvement Program. This letter encouraged utilltles to '

voluntarily install a hardened vent under 10CFR50;59.

Our' review of SECY 89-017 indicates that the primary benefit of the' hardened vent is the reduction of risk associated with the loss of decay heat removal ,

sequence. Therefore, it is the intention of TVA to install a hardened vent to reduce the risk of the loss of decay heat removal sequence:at BFN. TVA will 1 be working-with the BHR Owners' Group to develop generic design criterla'for the hardened vent. It is anticipated that the generic design criteria will be available'for NRC review by April 30, 1990. . Specific design details will be developed as TVA completes the appropriate portions of the Probabilistic Risk Assessment for BFN and studies the possibility of systems interaction between the vent and existing plant design. It is TVA's intent to install the hardened vent on Unit 2 during the first scheduled refueling outage after l

,. restart. This refueling outage is currently scheduled approximately 18 months

-after restart. Such an accelerated schedule will require expedited approval of the BWR Owners' Group generic design criteria and optimum materials '

availability. If difficulties with design or materials develop TVA will discuss the problems and schedule for the modification with the staff. The ,

hardened vent will be installed before the restart of Units 1 and 3.

It is the belief of TVA that the risk of the loss of decay heat removal sequence is already low. The installation of the hardened vent will further reduce risk of this sequence and make a significant contributton to closing the NRC's Mark I Containment Performance Improvement Program.

The commitment contained in this letter is listed in the enclosure.

p 4030

' \

8911090005 891030 PDR ADOCK 05000259 P PDC An Equal opportunity Employer

p.

L.,

[ . .

U.S. Nuclear Regulatory Commission i

D- o' Please refer,any questions concerning this submittal to Patrick.P. Carier, BfN

, ' Site Licensing, (205) 729-3570, b Very truly yours,

TENNESSEE VALLEY AUTHORITY f,  % 9 icensing Mana/r, Nuclear '

and Regulatory Affairs ,

Enclosure cc-(Enclosure): - l

'Ms. S. C. Black, Assistant Director  !

for Projects TVA Projects Division U.S. Nuclear Regulatory Commission 1)ne White Flint, North 11555.Rockville Pike Rockville, Maryland 20852.

Mr. B. A. Ullson, Assistant Director for Inspection Programs TVA Projects Division U.S. Nuclear Regulatory Commission Region II 101 Marietta Street, NH, Suite 2900 Atlanta, Georgia 30323 p

NRC Resident Inspector Browns Ferry Nuclear Plant Route 12, Box 637 Athens, Alabama 35609-2000 I

5 k

)

e

.'n. xx m ,

. n;'  : x

,. l/. y ' a -,,,.c,,.,,. , '

, f;q's f J 1, 7:p , '

a m < ..y :J m ,> ,

' (1 s- '

m.a, . pe . , ..

m . ,:o. y .. .

s y' v. ,. . m. -, .

n G f' . . . ' .',

p, ,

', 1D:

iv ,

Enclos'ure n.

+.o... i 1 . a v'..

p,; s $, /8 ' )..Dv' sL, ' Commitments Contained in' Letter l

itc. A, s : s

-o. Hardenedm.Wetwell.. Vent:(Gene.ric. Letter .(Gl.] 89-16); .

j

..., . 9, _ - -

^l^' . s k l. \ 1

• i S' O ;. } l i.. , , , . . , ,

$ g:,jF,' , ,!The hardened' vent will: beilnstalled 'in BFN Unit 2 'd4

. i1 t, M.; outage a_nd'before restart:for Un.lts lJandL3.~

, mf. "- '

m.

3.-

y

-1 4; . t St i 1 ,

il I r ,y+,

i a r;

,s l ,

5 i

^' ,

4 4

? .n s '

,' s . 5 t

'M.' [J ' 2 1 i

.'l , ' i n.3 ,

.'- 4,},6 /! t l

?) , y t :4

. .l

- ci f b

• b

, > l; { ',

.J3 m 1 g

.i -

.. ,1

,I o' h., i ;' . rf'

. k i

1,- 7 1; ;e .su 2,. s . F

-g 4 sf

,, , t' :g 7 4 3

. ~,j . ,

^h

, ,,,{,

r ' . ip  % , y' J '

a >

T '

,s, 2

r^

.'r ,

4 ) I L

,6 ' '

'i

-i. q' n h ', 1 5 , '$

i

r. g s

,h..

f, a; , s- I t

.-a I

't ? ,

, , h,\ _

i I' i b

f

- (5 s

- L. _

L

, . f' '

,4 .F 5

s e I f, a 4

r ;_, 1 c 1 t

* -5 i

\<]'

,s..

n. . .

I i s' i P

,i,. .

e i.l ,.. < -

i-

- t r

7 f'

il .

( ,l .. .

I

,.<. . I

' J/

!  ! t i , ,.,- r

-. .' ' P i

.. d.

i t_ J o.g g*, y 9-

' I ,4j' I t_

., I. 1[ - k

.-g .,. ,

.'=<j e f'

(

l l

C 1 t

-' - / , [

' %f

_.{';  ; f , h' i ,

'y_

I + , e d ,'

,t,'-

,~# ,

,]~ 4,, .. ,..', , ,3. .{, ,

" '--,--da . , , , , , , _

.i

~ , , , , , , , ,

., ,