ML20100H092

Responds to Violations Noted in Insp Repts 50-361/95-26 & 50-362/95-26.Corrective Actions:Util Performed Formal 10CFR50.59 SE for Orifice Body Replacement & Completed Revised UFSAR Change Page

ML20100H092
Person / Time
Site:	San Onofre
Issue date:	02/20/1996
From:	Nunn D SOUTHERN CALIFORNIA EDISON CO.
To:	NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
References
NUDOCS 9602270066
Download: ML20100H092 (3)

Text

1

SoUHHN C UFORNIA Dwight E. Nunn

,{ Vice President sa unwn nnwunmut ame.ni

'I February 20, 1996 '

t

.U..S. Nuclear Regulatory Commission -

Attention: Document Control Desk Washington D. C. 20555

Dear Sir:

L

Subject:

Docket Nos. 50-361 and 50-362  :

Reply to a Notice of Violation (IR 95-26)

San Onofre Nuclear Generating Station, Units 2 and 3

Reference:

1) Letter, Thomas P. Gwynn (NRC) to Mr. Harold B. Ray (Edison), NRC Inspection i Report 50-361/95-26 and 50-362/95-26, dated January 19, 1996

2) Meeting summary from James E. Tatum, Project Manager Project Directorate V, to Edison, dated October 11, 1989.

Reference 1 provided the results of a routine engineering inspection conducted from November 13 through December 1, 1995. .

The enclosure to Reference 1 transmitted a Notice of Violation l for: a).the apparent failure to perform a 10 CFR 50.59 safety evaluation when Edison substituted a valve body for a flange body holding the reactor coolant system gas vent flow-restricting orifice, and b) the failure to update the UFSAR to reflect the replacement of the flow-limiting orifice with an orificed gate ,

valve.

Prior to the implementation of Field Change Notice (FCN) F9329M, >

an operating procedure controlled the installation of the orifice plate in its flange holder. This was done to allow the orifice plate to be removed in MODE 6, yet ensure the orifice plate was reinstalled prior to entering MODE 4 where its presence is  ;

. required.

FCN F9329M replaced the pipe flange orifice container with a gate  ;

valve containing an orificed disk identical in design I

requirements to the original design flow restriction requirements, i.e., the disk of the gate valve was drilled with 9602270066 960220  !

PDR ADOCK 05000361  % 1 0 PDR

^

fg  ;

P. O. Bm 128 .)

((/

San Clemente, CA 9267' 714-36thl480 '

I(l0 r

Document Control Desk an identical sized orifice. Operational procedures were changed' from requiring an individual to visually verify the orifice plate was properly reinstalled at the head vent prior to entering MODE 5, to having an operator verify the orifice is in its proper position by checking the valve closed and locked prior to entering MODE 4. Additionally, a second independent check (inclusion in the locked valve program) was added to ensure the valve orifice is in its proper closed and locked position.

Reference 2 documented Edison's commitment to use NSAC/125 as our method of ensuring compliance with the provisions of 10 CFR 50.59. .The provisions of NSAC/125 were carried over into FCN procedure, SO123-XXIV-10.21, Rev 4, " Field Change Notice (FCN) and Field Interim Design Change Notice (FIDCN) . " The FCN procedure specifies the NSAC/125 screening criteria appropriate to reasonably determine if a 10 CFR 50.59 safety evaluation is necessary. For FCN F9329M, Edison engineers used the screening criteria contained in SO123-XXIV-10.21, Rev 4, and concluded there was no change to the design function or design bases, and that the written discussion of the RCS gas venting system as described in the UFSAR was appropriate for the modified system without change.

Edison has performed a formal 50.59 safety evaluation for the orifice body replacement. The 50.59 evaluation concluded the change did not constitute an unreviewed safety question. This 50.59 was completed February 12, 1996.

Part B of the violation, Reference 1, also identified the failure to update the UFSAR to reflect the replacement of the flow-limiting orifice with an orificed gate valve. Edison engineers erred when they reviewed the UFSAR in that they missed the sketch that depicted the original design. Edison has completed a revised UFSAR change page for submission in the next scheduled UFSAR update to properly depict the change. Edison has also issued required reading on the incident to the appropriate engineering staff to facilitate thorough reviews of future UFSAR description and figure changes. Full compliance was achieved on January 24, 1996, when NEDO initiated UFSAR change request SAR23-424 to update the UFSAR attachment Figure 9.3-15. ,

The' referenced cover letter requested Edison evaluate whether the UFSAR was being accurately maintained. Edison is reviewing the issue of UFSAR accuracy, and will provide our conclusions and any 3

_ _ . . - . _ _ - . . . ~ . _ . . . - .

. .. . i l

Document Control Desk l l

- appropriate corrective actions and schedules in a separate letter ,

within 60. days.

If you-have-any questions, please call me.

Sin erely, N -

}Y - ,

l L

cc: L. J. Callan, Regional Administrator, NRC Region IV T. P. Gwynn, Director, Division of Reactor Safety, NRC Region IV J..'E. Dyer, Director, Division of Reactor Projects, NRC Region IV  :

K. E. Perkins, Jr., Director, Walnut Creek Field Office, i

-NRC Region IV -

J. A. Sloan, NRC Senior Resident Inspector,' San Onofre Units 2 and 3 M. B. Fields, NRC Project Manager, San Onofre Units 2 and 3 I

i i

f

-1 n - e-vr-