ML20216H122

Requests That NRC Exercise Enforcement Discretion to Allow Licensee to Remain in Mode 1,power Operation W/O Having Performed Portions of SRs 4.8.1.1.2f.4)a) & 4.8.1.1.2f.6)a) During Shutdown.Lar Will Be Submitted

ML20216H122
Person / Time
Site:	Comanche Peak
Issue date:	03/13/1998
From:	Terry C, Walker R TEXAS UTILITIES ELECTRIC CO. (TU ELECTRIC)
To:	NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
Shared Package
ML20216H126	List: ML20216H122 ML20216H136
References
TXX-98078, NUDOCS 9803200183
Download: ML20216H122 (7)

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March 13, 1998

& PrincipalNuclear Oficer l U. S. Nuclear Regulatory Commission Attn: Document Control Desk Washington, DC 20555

SUBJECT:

COMANCHE PEAK STEAM ELECTRIC STATION (CPSES) UNITS 1 AND 2 DOCKET NUMBERS 50 445 AND 50 446 ENFORCEMENT DISCRETION FOR A.C. SOURCES. OPERATING REF: 1. NUREG 1600. General Statement of Policy and Procedures for NRC Enforcement Actions," dated June 1995 {

2. NRC Inspection Manual. Part 9900, " Operations - Enforcement Discretion," dated November 2, 1995

3. TU Electric Letter logged TXX 98077 from C. L. Terry to NRC dated March 12, 1998

4. TU Electric Letter logged TXX 98074 from C. L. Terry to NRC dated March 10, 1998

5. TV Electric Letter logged TXX 98076 from C. L. Terry to NRC dated March 12, 1998 In accordance with the guidance provided by reference 1. Texas Utilities l

Electric Company (TU Electric) requests that the Nuclear Regulatory Commission (NRC). exercise enforcement discretion to allow CPSES Units 1 and 2 to remain in MODE 1. POWER OPERATION without having performed portions of Surveillance Requirements 4.8.1.1.2f.4)a) and 4.8.1.1.2f.6)a) during shutdown. Without the. requested enforcement discretion, compliance with CPSES Technical Specification 4.8.1.1.2f would require a reactor

' shutdown in order to demonstrate the OPERABILITY of the 480 volt motor control center (MCC) undervoltage load shed relay contacts. Compliance without enforcement discretion would require that TU Electric shutdown both units.

The referenced section of the NRC Inspection Manual (reference 2) provides

. guidance on the information to be included in a request for enforcement J discretion. The sections below are arranced to correspond to that l guidance. I h'

9803200183 990313 PDR I

P ADOCK 05000445 PDR COMANCHE rEAK STEAM ELECTRIC STATION P.O. Box 1002 Glen Row. Texas 76043-1002 .-

TXX 98078 Page 2 of 7

1. REQUIREMENT / REQUEST:

Surveillance Requirement 4.8.1.1.2f requires, in part, that certain A.C.

electrical sources be demonstrated OPERABLE by performing the Surveillance Requirement at least once per 18 months. "during shutdown." Failure to perform the Surveillance Requirement within the 18 month frequency plus allowances allowed per Surveillance Requirement 4.0.2. would_ result in failure to perform a Surveillance Requirement. In accordance with Surveillance Requirement 4.0.3 this failure to perform the Surveillance Requirement would constitute a noncompliance with the OPERABILITY requirements for the LCO. Also in accordance with Surveillance Requirement 4.0.3 the ACTION requirements may be delayed for up to 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> to permit completion of the surveillance when the allowable outage time limits of the ACTION requirements are less than 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />.

With respect to Surveillance Requirements 4.8.1.1.2f.4)a) and 4.8.1.1.27.6)a). TU Electric requests that the NRC not enforce the requirement to perform the surveillance "during shutdown", in order to demonstrate the OPERABILITY by verifying load shedding occurs due to a loss of offsite power. Failure to perform the Surveillance Requirements l during MODE 1. POWER OPERATIONS, would result in the inoperability declaration of both diesel generators for each unit. With two diesel generators declared inoperable. LC0 3.8.1 ACTION f. requires in part, to

" restore at least one of the inoperable diesel generators to OPERABLE status within 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> or be in at least HOT STANDBY within the next 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> and in COLD SHUTDOWN within the following 30 hours3.472222e-4 days <br />0.00833 hours <br />4.960317e-5 weeks <br />1.1415e-5 months <br />."

TU Electric requests that the NRC exercise enforcement discretion to not enforce compliance with the "during shutdown" portion of Surveillance Requirement 4.8.1.1.2f. in order that CPSES not be required to shutdown both reactor units to allow surveillance performance or declare otherwise OPERABLE diesel generators inoperable and comply with LCO 3.8.1 ACTION f.

Additionally. CPSES will verify the portion of the Surveillance Requirements which had not previously been tested. This verification will be accomplished prior to the expiration of the time period provided by the enforcement discretion requested in Reference 3 above for Surveillance i Requirement 4.0.3. As such. CPSES will consider the surveillances to be complete with the exception of literal compliance with the "during i shutdown" requirement.

2. CIRCUMSTANCES:

During the process of conducting reviews in accordance with U.S. NRC Generic Letter 96 01. CPSES discovered it was not positively verified that certain contacts from the undervoltage relays cause load shedding at the 480 volt HCCs. Therefore complete testing in accordance with Surveillance Requirements 4.8.1.1.2f.4)a) and 4.8.1.1.2f.6)a) has not been performed. A parallel circuit path containing a contact from the Diesel Generator output breaker exists and could not be conclusively eliminated as causing the observed load shed during performance of previous integrated tests.

This omission in the surveillance program at CPSES has been present since

TXX 98078

'Page 3 pf 7 the time of initial license end was identified on March 12. 1998._at 5:18 p.m. CST. As the omission constitutes the failure to perform a.

-Surveillance Requirement within the surveillance frequency plus allowable extension in accordance with Surveillance Requirement 4.0.2. 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> from March 12. 1998. at 5:18 p.m. CST is allowed per Surveillance Requirement 4.0.3 to perform the Surveillance Requirement, during such time the ACTION requirements may be . delayed. . Per Reference 3. TU Electric has requested an extension of Surveillance requirement 4.0.3 to allow an additional 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> to complete testing. A determination of root cause will be evaluated and reported as required in the ensuing Licensee Event Report required per 10CFR50.73.

TU Electric believes that crediting performance of portions of Surveillance Requirements 4.8.1.1.2f.4)a) and 4.8.1.1.2f.6)a), during POWER OPERATIONS as opposed to "during shutdown" is acceptable with respect to overall safety and does not constitute an unreviewed safety question as detailed in the following sections.

3. SAFETY SIGNIFICANCE AND POTENTIAL CONSEQUENCES:

The safety function of the undervoltage relays is to shed unnecessary equipment loads on the A.C. bus and allow an operating diesel generator to be connected to the A.C. bus power emergency equipment. These relays are relied upon to ensure that the necessary equipment is shed from the bus at the appropriate time. Failure of the affected equipment to properly shed loads would place the operators in a situation where manual operator actions would be neces:;ary to remove the unnecessary equipment from the A.C. bus.

TV Electric has reviewed the required testing and has determined that acceptable tests for demonstrating OPERABILITY of the undervoltage relay contacts can be performed during POWER OPERATIONS with no adverse effect to the A.C. electrical distribution system. TV Electric is aware that the preclusion from performing these surveillance tests at conditions other than shutdown is to avoid the potential for perturbations to the A.C.

electrical distribution system and thereby result in a challenge to safety systems. These tests will demonstrate that the contacts from the undervoltage relays close upon actuation of the associated relay. thus

~

completing the confirmation of the circuit by overlapping tests.

Downstream actuation of the relays and breaker trips was confirmed during the normal integrated surveillance test. Note that the bus tie breaker for MCC XEB4 3 for Unit 2 was not tested during the last surveillance test and was the subject of previous enforcement discretion (Reference 4) and License Amendment Request (Reference 5). Performance of this testing does not create the potential for a perturbation to the A.C. electrical distribution system while the reactor is critical.

TU Electric believes that the crediting of these segments of the

-integrative tests are both acceptable and appropriate during POWER OPERATIONS. The potential consequences resulting from a coincident shutdown of both units of CPSES and the possible perturbations induced

TXX 98078

-Ppge 4 ,of 7 into the A.C. grid are clearly higher than those of crediting these testing' segments during POWER OPERATIONS. A qualitative risk assessment

' based on the CPSES PRA concluded that the granting of the requested enforcement discretion will not have an adverse impact on risk for either CPSES Unit 1 or Unit 2. Therefore, the possible consequences of conducting a dual unit shutdown in order to demonstrate the OPERABILITY of the undarvoltage relays far exceeds the potential consequences of crediting the testing segments in order to satisfy the Surveillance Requirements.

4. UNREVIEWED SAFETY OVESTION / NO SIGNIFICANT HAZARDS CONSIDERATION:

TU Electric has considered the criteria for assessing the potential of creating an unreviewed safety question or a significant hazards consideration with the exercising of enforcement discretion. In evaluating if discretion in enforcement constitutes a significant hazard the criteria of 10CFR50.92(c) is discussed below:

1. Do the proposed changes involve a significant increase in the probability or consequences of an accident previously evaluated?

Crediting performance of the portions of surveillance testing necessary to demonstrate the OPERABILITY of the undervoltage relays, will not increase the probability or consequences of an accident previously evaluated. The conclusion has been reached that the probability of initiating a perturbation in the A.C. electrical distribution system is not created via the crediting of the tests.

As the testing will be conducted on only one train per unit at a given time, no increase in consequences, other than those previously postulated, are considered credible.

2. Do the proposed changes create the possibility of a new or different kind of accident from any accident previously evaluated?

Perturbations in the A.C. electrical distribution system have been fully considered within the Final Safety Analysis Report. No new or different kind of perturbation or accident is deemed credible from crediting the performance of the testing.

3. Do the proposed changes involve a significant reduction in a margin of safety? ,

' Crediting the required testing does not create any new failure  ;

scenarios or A.C. electrical distribution perturbations, no associated margin is expected to be reduced. As such, there is no reduction in any margin of safety.

TU Electric has performed a safety evaluation, and has determined, in accordance with 10CFR50.59 that crediting the performance of the segments of testing necessary to demonstrate the OPERABILITY of the undervoltage  !'

relays does not constitute an unreviewed safety question.

i

TXX.98078

-Page 5 of 7 In summary, using 10CFR50.59 and 10CFR50.92 TV Electric has determined that crediting the necessary testing does not constitute an unreviewed safety question or a significant hazard.

5. ENVIRONMENTAL CONSEQUENCES:

The request only involves the crediting of performance of testing within the plant. These activities and their potential consequences are limited to the plant and will not result in any unplanned releases that could impact the environment.

6. COMPENSATORY ACTIONS:

Performance of the required testing will be conducted on only one train per unit at any given time. Although not necessary, this action precludes a common occurrence to both trains. This compensatory measure will be in place during the conduct of the tests. All contacts of concern will have been tested at power prior to the expiration of the time period provided in Reference 3 above for Surveillance Requirement 4.0.3.

7. DURATION:

The requested duration is based upon the time required for the NRC to process a proposed change to the technical specifications. The requested duration is to commence upon approval of this enforcement discretion request and to expire upon disposition of the proposed license amendment.

8. SORC REVIEW:

This activity has been reviewed and approved by the Station Operations Review Committee (SORC).

9. CRITERIA FOR EXERCISING ENFORCEMENT DISCRETION:

Reference 2, section B item 1 provides the criteria for exercising enforcement discretion for an operating plant as follows:

For an operating plant, the N0ED is intended to (a) avoid undesirable transients as a result of forcing compliance with the license condition and, thus minimize potential safety consequences and operational risk or (b) eliminate testing, inspection, or system realignment that is inappropriate for the particular plant conditions.

This criteria reflects the NRC's policy as provided in reference 1.

Initiating a two unit shutdown to comply with the subject Technical Specifications would subject CPSES to an undesirable transient which poses greater safety consequences than crediting performance of the already completed Surveillence Requirements segments during POWER OPERATION.

TXX 98078

- Page 6 o,f 7

10. PROPOSED TECHNICAL SPECIFICATION CHANGE 11 A separate license amendment request (LAR) will be submitted by March 18.

1998, under a different letter. This LAR will request a one time exception to allow performance of portions of Surveillance Requirements 4.8.1.1.2f.4)a) and 4.8.1.1.2f.6)a) at power.

11. APPROVED LINE ITEM IMPROVEMENTS:

Prior adoption of approved line item improvements to the Technical Specifications or the improved Standard Technical Specifiestions would not have obviated the need for this enforcement discretion request.

12. ADDITIONAL INFORMATION REQUESTED BY THE NRC STAFF:

The NRC staff has requested no additional information.

CONCLUSION:

TV Electric requests the NRC grant the requested enforcement discretion to allow CPSES to credit the performance of Surveillance Requirements 4.8.1.1.2f.4)a) and 4.8.1.1.2f.6)a), for the undervoltage relays during POWER OPERATIONS.

If there is a significant change in the circumstances associated with this exercising of enforcement discretion. TU Electric will notify the NRC. A response is requested by 5:18 p.m. CST on March 13. 1998, i

a

1 a

TXX-98078 Page 7.pf 7 This communication contains the following new commitment which will be completed as noted:

[DF Number Commitment 27130 A separate license amendment request (LAR) will be submitted by March 18. 1998. under a different letter.

This LAR will request a temporary Technical Specification change which provides a one time exception to the requirement to perform testing required by Surveillance Requirements 4.8.1.1.2f.4)a) and 4.8.1.1.2f.6)a) during shutdown.

Sincerely, d2, $, V C. L. Terry By: M '

Roger'D. Walker Regulatory Affairs Manager RTB/rb c Mr. E. W. Merschoff. RIV Mr. T. J. Polich. NRR Mr. J. I. Tapia.-RIV CPSES Resident Inspectors l

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