ML20012E268

Responds to NRC 900226 Ltr Re Violations Noted in Insp Rept 50-423/89-23.Corrective Actions:Requirement to Review All Changes on Safety Sys for Potential Operating Procedure Changes Stressed to Operations & Engineering Personnel

ML20012E268
Person / Time
Site:	Millstone
Issue date:	03/23/1990
From:	Mroczka E NORTHEAST NUCLEAR ENERGY CO., NORTHEAST UTILITIES
To:	Russell W NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I)
References
A08569, A8569, NUDOCS 9004030080
Download: ML20012E268 (5)

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i March 23, 1990 )

! Docket No. 50-423 h A08569  !

Re: 10CFR2 Appendix C  !

i Mr. V. T. Russell Regional Administrator, Region 1  !

U. S. Nuclear Regulatory Commission j 475 Allendale Road i King of Prussia, Pennsylvania 19406 Reference (1): E. C. Venzinger letter to E. J. Mroczka, NRC Region 1 I Inspection No. 50-423/89-23, dated February 26, 1990.  !

Dear Mr. Russell:

Millstone Nuclear Power Station, Unit No. 3 Response to Notice of Violation i Inspection Report 50-423/89-23 I

Introduction l In a letter dated February 26,1990 [ Reference (1)], the NRC trans- f mitted the results of their routine inspection conducted at Millstone Unit No. 3 from November 28, 1989 to January 4, 1990. In its letter, j the Staff identified one violation. The violation concerned the  ;

removal of the automatic start capability of the service water booster 1 pumps, (1) without determining whether the change involved an  ;

unreviewed safety question, and (2) without changing the service vater  ;

operating procedure. The Staff requested that Northeast Nuclear >

Energy Company (NNECO) provide a written statement or explanation  :

describing: (1) the corrective steps which have been taken and the results achieved; (2) corrective steps which vill be taken to avoid i further violations; and (3) the date vhen full compisance vill be i achieved, pursuant to the provisions of 10CTR2, Appendix C, NNECO hereby provides the following response to the Notice of Violation ,

contained in Referenew (1).

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g-Hro V. To Russell A08569/Page 2

• March 23, 1990 l I

i NNECO Response to Violation NNECO's response to the Notice of Violation identified by the staff is I j set forth below:

A. Staff's statement of the Violation

1. 10CTR50.59(a)(1) states, in part. ... The holder of a license  !

authorizing operation of a utilitiration f acility may make changes in the f acility as described in the safety analysis y report, without prior Commission approval, unless the proposed change involves a change in the Technical Specifications  :

- incorporated in the license or an unrevieved safety question..." Chapter 9.2 of the Hillstone Nuclear Pover ,

Station Unit No. 3 Final Safety Analysis Report (FSAR) [

requires the service vater booster pumps to start automatically on a loss of of fsite power and supply cooling ,

vater to the motor control center and rod control area l ventilation unit in service.  !

Millstone Unit No. 3 Technical Specification Section 6.8.1 I 2.

requires, in part, that vritten procedures be established, implemented and maintained, as recommended in Appendix A of Regulatory Guide 1.33, Revision 2, February 1978. Service ,

vater operating procedure 3326A, a procedure recommended by  !

Regulatory Guide 1.33, requires the B train of service water  :

booster pumps to be in operation. Technical Specification  :

Section 6.8.2 states, in part, that changes to each procedure ,

of Technical Specification Section 6.8.1 shall be reviewed by '

the PORC/SORC, as appropriate, an6 shall be approved by the Unit Superintendent / Station Superintendent prior to ;

implementation.  ;

Contrary to 1 and 2 above, on February 25, 1989, the licensee removed the automatic start capability of the service vater booster pumps as documented in Chapter 9.2 of the FSAR, by tagging  !

out the power supply breakers without determining whether the change involved an unreviewed safety question and without changing the service vater operating procedure 3326A.

B. Background Each train's service water booster pump is interlocked with a motor operated valve (HOV) in the piping system in such a manner that the booster pump vill automatically start when its associated MOV is in the full open position. The original design for these HOVs had them opening either manually via a control switch in the Control Room or automatically upon receipt of a loss of power signal. The pump would then start once the valve reached its full open position.

i f . Mr. V. T. Russell A08569/Page 3 ,

i l

March 23, 1990

! (

In January 1986, it vas concluded that the B train MOV did not '

meet seraration criteria of the Branch Technical Position (BTP)

CMEB 9.5-1. In response, the dacision was made to leave the MOV i in the open position, with its associated booster pump running.

The service water operating procedure was modified to require this valve to be open and its pump running whenever the B train of l service water vas in operaticn. In mid-1988, a problem was  ;

identified by the valve manuf acturer that could have led to the  ;

valve operator becoming separated from the valve stem under ,

certain seismic conditions. This was a generic problem that  !

applied to both valves. In response to this concern, the decision -

vas made to also leave the A train MOV in the open position vith  ;

its associated booster pump running. The service water operating  :

procedure was not modified to reflect this operating configuration.  ;

In response to degrading performance in both booster pumps, and ,

because of the increased incidence of leaks in the service vater ,

piping in the ventilation unit, the supply breakers to the booster l pumps vere opened, thereby defeating the interlock between the MOV ,

and booster pumps. This action occurred on February 25, 1989.

Yellow caution tags were placed on the pumps' control svitches in -

the Control Room to notify operators that the supply breakers vere  !

open. The configuration of the breakers was also carried on the shift Turnover Report, along with instructions to close the breakers if the pumps vere needed to supply cooling vater to the ,

ventilation units. Over the succeeding months, discussions took  :

place between Operations and Engineering personnel on how best to  !

address the problems of pump and system performance. At no time '

did NNECO believe that the ability of the system to perform its i design function (maintaining area temperatures in the MCC/ Rod Control Area) vas compromised. In October 1989, NNECO initiated a Bypass / Jumper for the purpose of defeating the auto-start feature when the MOVs are open. This Bypass / Jumper was then forvarded to  !

Engineering for evaluation. The matter was still under evaluation  !

on January 3,1990, when the NRC resident inspector identified a  !

concern with the configuration of the booster pump breakers. L C. Root Cause The root cause of the subject Notice of Violation was personnel error. Specifically, Operations and Engineering personnel -

involved in making the decision to open the supply breakers failed to consider the possibility that opening the supply breakers may have constituted a change to the system, and therefore required a safety evaluation pursuant to the provisions of 10CFR50.59.

i Furthermore, personnel failed to realize that the change to the system configuration required a change to the service water system operating procedure.

i 5

Mr. V. T. Russell 408569/Page 4

. March 23, 1990 l

Y D. Corrective Action On January 3, 1990, after discussions with the NRC resident inspector, Operations personnel cleared the yellow caution tags and closed the supply breakers to both booster pumps. Since both MOVs vere still required to be open as a result of the previously discussed concerns, both pumps began operating continuously. This action restored the system to its design configuration, thereby placing the system in full compliance with the requirements of the FSAR.

t E. Actions to Prevent Recurrence The following actions have been taken to prevent this violation

from recurring:

(1) This violation has been reviewed vith Operations and Engineering personnel. The requirement to review all changes on safety systems for potential operating procedure changes was stressed.

(2) Engineering personnel vere reminded that changes to operating procedures may require an evaluation pursuant to the provisions of 10CFR$0.59 if a change is being made as a result of a modification to the system (either temporary or permanent).

(3) On February 2,1990, a change was made to the service water operating procedure to reflect the fact that the A train MOV must be left open, with its associated booster pump running whenever the A train of service vater is in operation.

(4) A change to the FSAR has been initiated to clarify the system design, the interlock between the MOV and booster pump, and the system response to a loss of power.

Reference (1) also expressed a concern in regards to " untimely notifi-cation and reporting of the potential problems with the 4160 volt fast bus transfer scheme". This issue vill be addressed in separate correspondence.

w-

. Nr3 V. T. Russell

, .A00569/Page 5 l*.*Narch23,1990 If you have any questions regarding the information contained in this letter, please contact us.

Very truly yours,

! NORTHEAST NUCLEAR ENERGY COMPANY V

MR '

E. J,Mirocska f

! Senior Vice President I

cci D. H. Jaf fe, NRC Project Manager, Millstone Unit No. 3

V. J. Raymond, Senior Resident Inspector, Millstone Unit Nos. 1, 2, and 3 U. S. Nuclear Regulatory Commission Attention

Document Control Desk Vashington, DC 20555 1