ML20128Q224

Application for Amend to License NPF-3,revising Tech Spec Table 4.3.1 to Provide for Testing to Confirm Operability of Shunt & Undervoltage Trip Devices of CRD Trip Breakers.Fee Paid

ML20128Q224
Person / Time
Site:	Davis Besse
Issue date:	05/29/1985
From:	Crouse R TOLEDO EDISON CO.
To:	Stolz J Office of Nuclear Reactor Regulation
Shared Package
ML20128Q229	List: ML20128Q224 ML20128Q245
References
1155, TAC-55352, TAC-59932, NUDOCS 8506040126
Download: ML20128Q224 (6)

Text

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.f TOLEDO

%ms EDISON RCHARO P. CROUSE Vce prenders Docket No. 50-346 $,w License No. NPF-3 Serial No. 1155 May 29, 1985 Director of Nuclear Reactor Regulation Attention: Mr. John F. Stolz Operating Reactor Branch No. 4 Division of Licensing United States Nuclear Regulatory Commission

' Washington, DC 20555

Dear Mr. Stolz:

Under separate cover, we are transmitting three (3) original and forty (40) conformed copies of an application for Amendment to Facility Operating License Nc. NPF-3 for the Davis-Besse Nuclear Power Station Unit No. 1.

-This application requests that the Davis-Besse Nuclear Power Station Unit 1 Technical Specifications, Appendix A, be revised to reflect the changes attached. The proposed' changes involve Table 4.3-1.

The attachment identifies the proposed change and its safety evaluation

.and a significant hazard consideration. The proposed change provides for testing to independently confirm the operability of the shunt and under-voltage trip devices of the control rod drive trip breakers.

Toledo Edison requests that this amendment request be granted by January, 1986.

Enclosed is a check for $150 as required by 10CFR170.12(C) for license application.

Very truly yours, B P %Q +

RPC LCS: GAB f'

Attachment i p cc: DB-1 NRC Resident Inspector State of Ohio U g g 4

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8506040126 850529  !

PDR ADOCK 05000346 P PDR THE TOLEDO EDISCN COMPANY EDISON PLAZA 300 MADISON AVENUE TOLEDO, OHIO 43052 1

_ _ _ _ _ _ _ _ _ _ . _ _ ___________________.._____________________d

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- APPLICATION FOR AMENDMENT TO FACILITY OPERATING LICENSE NO. NPF-3 FOR DAVIS-BESSE NUCLEAR POWER STATION UNIT NO. 1 Enclosed are forty-three (43) copies of the requested changes to the Davis-Besse Nu: lear Power Station Unic No. 1 Facility Operating License No. NPF-3, together with the Safety Evaluation for the requested change.

The proposed changes include Table 4.3-1.

t By /s/ Terry D. Murray Terry D. Murray Assistant Vice President, Nuclear Operations t'

For R. P. Crouse Vice President, Nuclear Sworn and subscribed before me this 29th day of May, 1985.

/s/ Laurie A. Hinkle, nee (Brudzinski)

Notary Public -- State of Ohio My Commission Expires May 16, 1986 SEAL.

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Docket No. 50-346 License No. NPF-3

-Serial No. 1155 May 29. 1985 Attachment I. Changes to-Davis-Besse Nuclear Power Station Unit 1, Appendix A Technical Specifications Table 4.3-1 A. Time required to Implement. This change is to be effective upon NRC approval.

B. Reason for Change (Facility Change Request 85-0064, Rev. A).

This request is in response to the requirement in the Supplemental Safety Evaluation Report for Davis-Besse Unit 1 Generic Letter 83-28, Item 4.3, Reactor Breaker Automatic Shunt Trip. The attached change

'for Table 4.3-1 for testing to confirm the OPERABILITY of the shunt and undervoltage trip devices.

C. Safety Evaluation (See Attached)-

D. Significant Hazard Consideration (See. Attached)

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F SAFETY EVALUATION

. INTRODUCTION:

This'FCR is a result of a directive'from the NRC in.their safety evaluation report.on our addition of the shunt trip device in each of four Reactor

. Trip Breakers.(FCR 84-0026, Rev. A).

REFERENCE:

NRC Supplement Safety Evaluation Report Log No. 1683.

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-' B&W report on " Review of On-Line Test Intervals. for the Reactor Trip

' System."

'FCR 84-0026 (Rev. A) Addition of the shunt trip devices to each Reactor Trip Breaker.

DISCUSSION:

The directive states, "We require that technical specification explicitly note that testing independently confirms the operability of the shunt and undervoltage trip attachments (devices)." The term attachment applies to a Westinghouse breaker, whereas the term devices applies to our GE breakers.

The. safety function of the technical specification is to provide.a surveil-lance schedule for testing the reactor trip breakers, to assure the operability' requirements of the reactor trip system are met.

LThe. safety. function of the reactor trip breakers is to remove the power from the Control Rod Drive Mechanisms (CRDMS) allowing the safety &

. regulating rods to drop into the core, bringing the' reactor to a sub-

, ' critical condition whenever it receives'an automatic trip command signal-(undervoltage conditions) from the Reactor Protection System (RPS),

Anticipatory Reactor Trip Systems (ARTS). or a manual trip command signal; from the: operator. (

Reference:

FSAR para. 7.4.1.1). .The function of the

' shunt trip device is to provide additional assurance that the reactor trip breakers will open'when required. There is no. safety function associated.

, with the shunt trip devices.

The. addition to the Davis-Besse' Unit 1 technical specification,should not

-result in additional-testing.as procedures have previously been modified to incorporate the requirement to independently confirm the shunt and undervoltage trip device. This was accompli-hed following the addition of the shunt! trip' devices. We had made the interpretation that this was

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necessary to meet the existing technical specification operability require-ments.

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lThe only function of.this FCR is to meet the directive to incorporate the frequired verbiage in the technical specification.

.The frequency of testing as a result of'the independent verification was addressed by the B&W Owners Group in their report entitled " Review of On-Line. Test Intervals for the' Reactor Trip Systems."

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This report concluded:

"The wearout evaluation indicated that the RTS components are not susceptible to wearout caused by testing. The breakers are the major components affected by test cycling and the GE AK-2 breaker has a design cycle objective of 12,500 cycles. Aging of the trip shaft bearing lubricant is virtually eliminated as a concern when the Mobil 28 lubricant is installed." (This is completed at Davis-Besse.)

"Therefore, for the breakers, common mode failure due to wearout is not a significant source of RTS unavailability. Other components do not exhibit histories that indicate that wearout is a concern.

Reduced redundancy caused by testing does not significantly contribute to RTS unavailability. Reduced redundancy is primarily due to bypass testing of the RPS and ARTS sensor strings, which has the effect of reducing the trip logic from 2/4 to 2/3 for the duration of the tests. Other on-line tests (breakers, electronic trip, trip modules) are performed with the channel tripped and, therefore, in a " fail-safe" condition that does not affect (RTS) unavailability."

CONCLUSION:

Additional testing should not result from this technical specification change as Station procedures already include the requirement to independently confirm the operability of the shunt and undervoltage trip devices.

Surveillance testing now require 3 trips per month or 36 per year. The design number of cycles 12,500 over the 40 year plant life allows for an average of 312 per year. This margin is more than sufficient to allow for-reactor trips and bench testing (the 12 month schedule for maintenance of the breakers.)

Based on this, the technical specification change will not result in an unreviewed safety question.

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Significant Hazard Consideration This amendment request to add surveillance requirements for testing to confirm the OPERABILITY of the SHUNT and UNDERVOLTAGE trip devices does not involve a Significant Hazard.

Resulting from the Salem ATWS event and Generic Letter 83-28, Licensees were requested, as part of their response, to review their Technical Specifications and submit any needed changes. The attached amendment request provides Toledo Edisons changes to their Technical Specifications.

These changes provide that testing independently confirms the operability of the shunt and undervoltage trip' attachments (devices). 'These devices are checked as part of the monthly channel functional test and before start up if the surveillance has not.been performed in the past seven days.

These. changes are an additional testing requirement, not presently included in the Technical Specifications, to be performed to ensure the safety function of the reactor trip breakers.

The Commission has provided guidance concerning the application of the standards in 10 CFR 50.92 by providing certain examples (48 FR 14870).

One of the examples of actions involving no significant hazards consider-ations relates to a c.hange that constitutes an additional limitation, restriction, or control not presently included in the technical specifi-cations: for example, a more stringent surveillance' requirement. The testing of the reactor trip breaker is an additional testing limitation not presently included in our Technical Specifications.

Therefore, based on the above, this. amendment request is not a Significant Hazard.