ML20010G377

Summary of 810722 Meeting W/Util Re Audit on Seismic Reassessment for Mechanical Components

ML20010G377
Person / Time
Site:	Fermi
Issue date:	09/03/1981
From:	Kintner L Office of Nuclear Reactor Regulation
To:	Office of Nuclear Reactor Regulation
References
NUDOCS 8109180388
Download: ML20010G377 (4)

Text

e gy' W-

/

d W

r V

SEP 3 1S8)

(Docket W50-341?

APPLICANT:

Detroit Edison Company FACILITY:

Femi 2

SUBJECT:

SUXiARY OF JULY 22, 1981 ?!EETING REGARDING OPERATING LICENSE 4

PIVIEW On July 22, 1981, the Mechanical Engineering Branch perforne( an audit on the seismic reassessment for Femi 2 nechanical components. The seismic reass-essment wcs perfomed by Detroit Edison as requested by the NRC staff using site specific seismic response spectra.

The HRC staff participating was D. Terao, Mechanical Engineer Branch, NRR. The Detroit Edison engineering personnel included M. Williams and J. Casiglia.

The NRC staff discussed questions that arose after reviewing the Fermi 2,

" Supplementary Seisaic Evaluation Report", dated July 15, 1981. Detroit Edison addressed the NRC concerns and provided clarification and justification as necessary.

In our audit, we considered all essential seismic Category I piping systems required for the mitigation of the postulated accident. We found several residual heat removal (RiiR) Division I piping subsystems that were not conputer analyzed in the seismic reassessment; however, those piping subsystems that were excluded fro'n the reassessment were evaluated qualitatively by inspecting the seismic structural response spectra applicable to those subsystems.

In comparing the design basis structural response spectra (i.e.1.875 x OBE) with the new site-specific structural response spectra, we concluded that for the required subsyste.ns, the design basis spectra provides an ample margin of conservatism over the site-specific spectra. The worst case site-specific spectra where the design basis spectra were significantly exceeded by the sitespecific spectra were found to be not applicable to the safety-related nechanical components required for accident nitigation.

As part of our review, the staff audited three of the essential balance-of-plant (BOP) piping subsystem analyses; feedwater, reactor core isolation cooling, and residual heat re'noval subsystens. The staff found that most of the piping stresses decreased. Those stresses that increased were signficantly below the ASME Code allowable stress limits. All piping stresses remained within the ASME Code allovables. All support loads that were audited (including large bore and instrinentation supports) were within their design limits.

All equipment nozzle reactions applicable to the three audited subsystems i

decreased with the new site-specific spectra.

l N"">

8109180388 810903 om)

PDR ADOCK 05000341 A

p yg - - -. - -.

~~--------

.. - -. -. ~

n;c ronu ais no<soinacu ouo OFFICIAL RECOFiD COPY

,uswo weo-men

((

}r d

,f 3

y-3'

~-

2-During the audit, the staff discussed a yet unresolved concern with the

. appl icant.

In selecting the structural response spectra for the flSSS piping systens, the applicant had used the response spectra corresponding to the center-of-gravity of the piping subsystem. This method for the selection of response spectra is not acceptable to the staff. We are currently working on an acceptable resolution of thir issue with the applicant. We will report our resolution in a supplenent to the SER.

odgind SI8"'8%

t.eecr1. Kintner L. L. Kintner, Project Manager Licensing Branch No. 1 Division of Licensing cc: See next page i

l' 1

_/f Omce>. D.L..:.L..B.#.1? D. L.,.. L.......

euu.w, >.LKintner

'B ngbjood 9/1./n....... 9/.al.n.......

..................l NIC FORM 318 410<8M NRCM O240 OFFICIAL RECORD COPY "S**

'98w29 e2.

E c

Mr. Harry Taubgr Vice President Engineering & Coastruction Detroit Edison Company 2000 Second Avenue Detroit, Michigan 48226 cc:

Eugene B. Thomas, Jr., Esq.

LeBoeuf, Lamb, Leiby & MacRae 1333 New Hampshire Avenue, N. W.

Washington, D. C.

20036 Peter A. Marquardt, Esq.

Co-Counsel The Detroit Edison Company 2000 Second Avenue Detroit, Michigan 48226 Mr William J. Farner Project Manager - Fermi 2 The Detroit Edison Company 2000 Second Avenue Detroit, Michigan 48226 Mr. Larry E. Schuerman Detroit Edison Company 3331 West Big Beaver Road Troy, Michigan 48084 David E. iiowell, Esq.

32E9 Woodward Avenue Berkley, Michigan 48072 Mr. Bruce Little U. S. Nuclear Regulatory Commission Resident inspector's Office 6450 W. Dixie Highway Newport, Michigan 48166 Dr. Wayne Jens Detroit Edison Company 20JO Second Avenus Detroit, Michigan 48226

a "EET' ~ EUMMARY DISTRIBUTION

Docket File G. Lear tiRC PDR SEP 3 1981 WJohnston Local PDR S. Pawlicki TIC /flSIC/ Tera V. Benaroya fl. Hughes Z. Rosztoczy LB#1 Reading W. Haass H. Denton D. Muller E. Case R. Ballard

9. Eisenhut

11. Regan

/

R. Purple D. Ross B. J. Youngblood P. Check A. Schwencer Chief, Power Systems Branch F. Miraglia

0. Parr J. Miller F. Rosa G. Lainas W. Butler R. Vollmer W. Kreger J. P. Knight R. Houston R. Bosnak Chief, Radiological Assessment Branch F. Schauer L. Rubenstein R. E. Jackson T. Speis Project Manager LKintner MSrinivasan Attorney, 0;LD J. Stolz M. Rushbrook S. Hanauer OIE (3)

W. Gammill ACRS (16)

T. Murley R. Tedesco F. Schroeder D. Skovholt M. Ernst f4RC

Participants:

R. Baer C. Berlinger K. Kniel G. Vsnighton A. Thadani D. Tondi J, Kramer D. Vassallo P. Collins D. Ziemann bcc: App 1 kant & Service List O

'e i

.