ML20059K706

Disagrees W/Position That More Detailed Design & Safety Assessment Using Ipe/Pra Appropriate Framework,Per Generic Ltr 89-19

ML20059K706
Person / Time
Site:	Fort Calhoun
Issue date:	09/14/1990
From:	Quay T Office of Nuclear Reactor Regulation
To:	Gates W OMAHA PUBLIC POWER DISTRICT
References
GL-89-19, TAC-74944, NUDOCS 9009240190
Download: ML20059K706 (4)

Text

,

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

.r ,

(  ;~ ,

1# UNITED' STATES

,y ]' 'p,; .- NUCLEAR REGULATORY COMMISSION j yfj y a ' WASHINGTON, D, C. 20$$5 k.....[{

Y , September 14,-1990 T -Docket;No. 50'-?B5 1

.Mr. W; Gary, Gates . . . .

. . Division Manager - Nuclear 0perations l

=0maha Public Power District ,

444 South.16th Street Hall' L

Mail Stop 8E/EP 4' L

0maha, Nebraska- 68102-2247

Dear Mr. Gates:

a 4

SUBJECT:

GMAHA PUP.IC POWER DISTRICT'S RESPONSE TO GENERIC LETTER 89-19 , '

7 , REGARu!NG SAFETY IMPLICATIONS OF CONTROL SYSTEMS IN LWR NUCLEAR-POWER PLANTS (TAC NO. 74944)  ;

l1 , By . letter dated March 19, 1990, OmahaPublicPowerDistrict'(OPPD) responded-P g to Generic Letter (GL) 89-19, " Request for Action Related to Resolution of 1

, lication of Control Systems in LWR

% ' Nuclear Unresolved. Plants'Safety' Pursuant Issuetc 10A-47,CFR 50.54' Safety-Imp (f)." :In this response Jyou indicated that you..had. initiated a' modification request to provide automatic steam a generator overfill rotection', and that this modification was' tentatively: .

, scheduled for comp 1 tion by the end of the 1991 refueling outage, which is your ,i

!, next refueling outage.'

~ '

By' letter dated August 22, 1990, you' revised your position on implementing the above mentioned modification based on Combustion Engineering Owners: Group s . 1 (CEOG's)reviewofthisissue. Your. revised position stated that;it.was OPPD's- . ,

position that automatic steam generator overfil1~ protection should not be , ,

implemented until the Individual Plant Examination (IPE)/Probablistic Risk '

Analysis-(PRA) for Fort Calhoun Station (FCS) is completed. Youiindicated .. 4

that;the PRA will better address the CEOG's' concern regardingLthe~ data utilized: ]

in determining the probability of occurrence ofl overfill events, and that: t

~

significantfdifferences do exist between systems used as the. basis of GL.89-19

and'those systems.that exist at FCS. 1 We~ do not agree with your position that a more detailed design.and safety  ;

-assessment using:the IPE/PRA is an appropriate framework to continue the

, evaluation of steam generator overfill safety impets.,- Previous NRC' analyses

, performed to evaluate alternatives to resolve USI 647, " Safety Implications of Control: Systems," provided insight with respect to the safety benefits,- <

impacts,iand costs of modifications for overfill prctection. Plant' specific.

' differences were considered'in the development of NU.tEG-1218 " Regulatory

. Analysis for Resolution of USI-47," Land in the preparation of the GL 89-19.

You'had' ample opportunity to provide cumments on thir, issue when the Federal

' Register notics was published in May 1989. 1

< Combustion Engineering (CE) plants, as a. class, do not provide steam generator overfill protection. -Overfill events have occurred at CE plants and other o ' light water reactors. The' consequences resulting from such events depend; largely on piping system integrity, are difficult to model accuretely, and '

thave large. uncertainties. -It.is for these reasons that IPE/PRA evaluation will W not' add significant information to close this issue. Further we believe that' 9009E40 ISO 9009I4

) f'$ /.  :

gan-ADock0500gg5 pu VW:

3 ,

- u - - .

ly . - .

k Mr. W. Gary Gates I the potential negative impacts of inadvertent isolation of feedwater can be made insignificant through sound design, with reliable equipment, and with implementation of a reasonable test strategy.

With regard to the implementation schedule for FCS, the staff agrees with the schedule submitted in your letter of March 19, 1990, which is responsive to the GL's suggested schedule. Also, the GL requested a Tech Spec change be submitted for staff review and approval for these changes. We request your response within 45 days from receipt of this letter.

Sincerely, ad<% $ Lwy ,

Theodore R. Quay, Acting Director Project Directorate IV-1 Division of Reactor Projects - 111,.

IV, V and Special Projects 1 Office of Nuclear Reactor Regulation '

cc:

See next page t

l 4

l i

l l .-

f

7. j ys. + +

jf j,

h. l . .L Mr. W. Gary Gates ,

't. Omaha Public Power District-- Fort Calhoun Station, Unit No l.

'I q  ;

s; .,

cc:

i Harry H. Voigt, Esg.

LeBoeuf Lamb, Leiby & MacRae #

1333 New Hampshire Avenue, NW 1 . Washington,:D.C. 20036 Mr. Jack Jensen, Chairman .

t

-Washington County Board

.of. Supervisors

, -Blair, Nebraska 68008- j l

Mr. Raymond P.' Mu111 kin, Resident Inspector U.S. Nuclear Regulatory Commission '

Post Office Box 309 '

a-  : Fort Calhoun, Nebraska 68023

! Mri Charles B. Brinkman, Manager. 1 Washington Nuclear Operations Combustion Engineering, Inc.

12300 Twinbrook Parkway, Suite 330

Rockville .MD-l20852' Regional Administrator, Region IV ,

"U.S.-Nuclear Regulatory Commission 0ffice of Executive Director r- .for Operations- .

h 611 PJan Plaza Drive, Suite 1000 Arlington.-Texas 76011'

' Harold Borchert. Director ,

Division of Radiological' Health '[~

Nebraska Dep.rtment of Health 301 Centennial Mall, South

' Post Office ~ Box 95007 ..

Lincoln.. Nebraska 68509 Mr. T.-L. Patterson,-Manager Fort Calhoun Station Post Office Box 399

. Fort-Calhoun, Nebraska 68023 D

I k

i i

I A

^ .

+

J . .-- -. . . . .

( 4

, . . . 1 o* ~

Mr. W. Gary . Gates 2 September 14,;1990 y

the potential negative impacts of inadvertent isolation of feedwater can be made insignificant through sound design, with reliable equipment, and with implementation of a reasonable test strategy.

~With regard to the implementation schedule for FCS, the staff agrees with the schedule submitted in your letter of March 19, 1990, which is responsive to

• the GL's suggested schedule. Also, the GL requested a Tech Spec change be submitted for staff review and approval for these chances. We request your-response within 45 days from receipt of-this letter

]

Sincerely, Original aigmod by:  ;

Theodore R. Quay, Acting Director Project Directorate IV-1.

Division of Reactor Projects - III, IV, Y and Special Projects Office of Nuclear Reactor Regulation CC:

See next page-DISTRIBUTION '

tN -OGC MS15 BIB A. Thadani D. Matthews .

NRC & Local PDR 5. Rhow J. Mauck E. Jordan MNBB3701 PD4 1 Reading S. Newberr K. Jabbour T. Quay D. Crutchfield ACRS(10)yP315 S. Richards S. Yarga B. Boger PD4-1 Plant File L. Constable, RIV G. Lainas L. Berry T. Bournia A=

OFC =:PD4 1/LA :PD4-1 :PD4 1/D :DRP/PM  :

" ...:.......$pm::5Ip .:..............

i NAME : - :LBerry > @ g.....:

TBourn

..... :lh . .::TQuay

..... . g\ :KJabbour s

SNewb  :

DATE :09/h/90 :09//o/90 :09/B/90 :09/IO/90 :00// 4 90  :

CFFICIAL RECORD COPY Document Name: RESPONSE TO GL 8919 74944

, ,, '; -,