ML20128H278

Application for Amends to Licenses DPR-39 & DPR-48, Clarifying & Adding Mode of Applicability for Rod Position Indicator Channels

ML20128H278
Person / Time
Site:	Zion  File:ZionSolutions icon.png
Issue date:	10/04/1996
From:	Mueller J COMMONWEALTH EDISON CO.
To:	NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
Shared Package
ML20128H282	List: ML20128H278 ML20128H301
References
NUDOCS 9610090296
Download: ML20128H278 (6)

Text

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Commonw calth 1.dison Company Zion Generating Nation

• ,101 Shiloh floulevant zion, iuamer Tcl M C? K,-lOS 1 October 4,1996

..t U.S. Nuclear Regulatory Commission Attn: Document Control Desk Washington, D.C. 20555

Subject:

Zion Station Units I and 2 Application for Amendment to Facility Operating Licenses DPR-39 and DPR-48 '

NRC Docket Nos.;50-295 and 50-304 This letter transmits, pursuant to 10 CFR 50.90, an application for an amendment to Appendix A of the Zion Unit I and 2 Facility Operating License, DPR-39 and DPR-48, to clarify the Mode of Applicability for the Rod Position Indicator Channels. The proposed amendment will add a Mode of Applicability to Technical Specification 3.2.3.D, Rod Position Indicator ,

Channels. The Modes of Applicability will be Mode 1 and Mode 2, and the Required Action for more than one inoperable Rod Position Indicator Channel per group or two per bank will require the unit to be in Hot Shutdown in four hours. This will allow calibration of the Rod Position Indicator Channels, which requires closing the trip breakers and withdrawing the control rod, prior to reaching a condition where the Rod Position Indicator Channels are required OPERABLE.

This application for amendment is comprised of the following attachments to this letter:

Attachment A provides a description and safety analysis of the proposed changes to the Technical Specifications.

Attachment B provides an annotated copy and a clean copy of the affected pages of the Current Technical Specifications (CTS).

Attachment C provides an evaluation of Significant Hazards Considerations for the proposed changes to the Technical Specifications in accordance with 10 CFR 50.92.

Attachment D provides an Environmental Assessment Statement for the proposed changes to the Technical Specifications in accordance with10 CFR 51.21 and 10 CFR 51.22.

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9610090296 961004 PDR ADOCK 05000295 P PDR A i nicor., Company

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i This proposed amendment has been reviewed and approved by Zion Station Onsite and

Offsite Review personnel in accordance with Comed procedures.

To the best of my knowledge and belief, the statements contained in this amendment application are true and correct. In some respects these statements are not based on my personal knowledge, but obtained information furnished by other Commonwealth Edison

employees, contract employees, and consultants. Such information has been reviewed in accordance with company practices, and I believe it to be reliable.

i Commonwealth Edison is notifying the State ofIllinois of this application for amendment by 1

transmitting a copy of this letter and its attachments to the designated state official.

1 Please direct any questions you may have concerning this submittal to this office.

i ,

I Respectfully,

),

J. H. Mueller i Site Vice President Zion Station Subscribed and swom to before me, a Notary Public in and for the State of UMimb and County of dd this MfL day of /VAfAd/As ,1996.

4,::- '0FFICIALSEAUR D Notary Pu e tate o 1 of l Notary Public (/ [:My Commission Expires 7/13/99 1

_a Attachments cc: NRC Regional'^dministrator - RIII Zion Station Project Manager - NRR Senior Resident Inspector - Zion Station Office of Nuclear Facility Safety -IDNS IDNS Resident Inspector Master Files Reg. Assurance File DCD Licensing 2

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ATTACHMENT A ZION NUCLEAR GENERATING STATION DESCRIPTION AND SAFETY ANALYSIS l FOR PROPOSED CHANGES TO FACILITY OPERATING LICENSES DPR-39 AND DPR-48 APPENDIX A TECHNICAL SPECIFICATIONS ROD POSITION INDICATOR CHANNELS OPERABILITY

DESCRIPTION OF PROPOSED CHANGE Comed proposes to amend Appendix A, Technical Specifications, of Facility Operating

' Licenses DPR-39 and DPR-48, to add a Mode of Applicability far the Rod Position Indication System, by requiring the Rod Position Indicator Channels to be operable during MODE I and MODE 2. This change is necessary in order to correct an ambiguous applicability associated i

with Limiting Conditions for Operation (LCO) 3.2.3.D.1, Inoperable Rod Position Indicator Channels, which effectively precludes operations necessary to declare the rod position indicator channels operable. .

The current Technical Specifications do not explicitly state a Mode of Applicability for LCO 3.2.3.D. The implied applicability of greater than or equal to Hot Shutdown with the Reactor Trip Breakers closed can be determmed through LCO 3.2.3.D.2, which requires the unit to be

placed in Hot Shutdown with the Reactor Trip Breakers open, within four hours.

LCO 3.2.3.D will be modified to have a Mode of Applicability when the Rod Position Indication Channels are required OPERABLE, which will be MODE I and MODE 2. LCO 3.2.3.D.1 will continue to require that not more than one rod position indicator channel per control rod group nor two rod position indicator channels per control rod bank shall be permitted to be inoperable at any time, except during hot rod drop timing measurements.

LCO 3.2.3.D.2 will be rewritten to be the Required Action, if the conditions of Section 3.2.3.D.1 cannot be met, the reactor shall be brought to at least the Hot Shutdown condition within four hours. This will allow calibration of the Rod Position Indicator Channels, which requires the control rods to be individually cycled their full length.

DESCRIPTION OF CURRENT REQUIREMENT LCO 3.2.3.D.1 states that not more than one rod position indicator channel per control rod group nor two rod position indicator channels per control rod bank shall be permitted to be inoperable at any time, except during hot rod drop timing measurements. LCO 3.2.3.D.2 states that if the conditions of Section 3.2.3.D.1 cannot be met the teactor shall be brought to at least a Hot Shutdown condition within four hours and the reactor trip breakers shall remain open. In addition, with a single Rod Position Indicator Channel out of service, continued operation is permitted, and with power greater than 50%, control rod positions are required to be checked indirectly at least once per shift by excore detectors, thermocouple or moveable incore detectors. During operation with power less than 50%, no special monitoring is required.

BASES FOR THE CURRENT REQUIREMENT The acceptance criteria for control rod position indication is that control rod positions must be known with sufficient accuracy in order to verify the core is operating within the group sequence, overlap, design peaking limits, ejected control rod worth, and with minimum SDM.

Power peaking, ejected control rod worth, or SDM limits may be violated in the event of a

0FSAR' accident with control bank or shutdown bank control rods operating outside their limits undetected. The control rod positions must also be known in order to verify the alignment limits are preserved. Control rod positions are continuously monitored to provide I operators with information that control rods are within their alignment limits.

REASON FOR REQUESTING AN AMENDMENT In order to perform the testing necessary to ensure a rod position indicator channel operable, l

the associated control rod must be withdrawn to verify proper tracking of the rod position j i

indicator channel. This requires closing of the Reactor Trip Breakers, which is implicitly  ;

prohibited by the current Technical Specification unless the Rod Position Indicator Channels

are operable. As such, the implied applicability of this LCO will not allow the trip breakers to be closed to perform the calibration. To avoid any possible conflict between the ability to

' perform rod position indicator channel calibration, which require the reactor trip breakers closed, and the implied applicability for the Rod Position Indicator Channels, a specific Mode of Applicability for LCO 3.2.3.D has been proposed. .

DESCRIITION OF THE PROPOSED REQUIREMENT A Mode of Applicability has been proposed for LCO 3.2.3.D. The proposed Applicability is j that Rod Position Indicator Channel operability would be required in MODE I and MODE 2. )

This would allow performing rod position indication system calibration, which requires the i reactor trip breakers closed, prior to the Mode where the rod position indication system is i required to be OPERABLE. In addition, LCO 3.2.3.D.2 will be renamed to be the Required l Action, and state that if the conditions of Section 3.2.3.D.1 cannot be met the reactor shall be brought to at least the Hot Shutdown condition within four hours.

The proposed changes are based on the requirements of all Amendments up to and including Amendment 172 for Unit I and Amendment 159 for Unit 2. The pages of Technical ,

Specifications indicating proposed changes are provided in Attachment B. '

BASES FOR THE PROPOSED REQUIREMENT The requirements on the Rod Position Indicator Channels are only needed in MODE I and MODE 2 because these are the only MODES in which power peaking factors are a concern. In this case, OPERABILITY of the Rod Position Indicator Channels has a potential to affect the safety of the plant. Control rod alignment limits ensure that power distribution and reactivity limits defined by the design power peaking and shutdown margin limits are preserved. As such, it is appropriate to require control rod position indication for verification of control rod alignment limitations in MODE I and MODE 2.

Control bank and shutdown bank control rod position accuracy is required during power operation. Rod Position Indicator Channels are not required in shutdown modes since shutdown margin limits can be ensured by chemical shim if indication is not available.

! NUREG-1431, Revision 1, " Improved Standard Technical Specifications," also has a Mode of Applicability of MODE I and MODE 2 for the Rod Position Indication System. The

' proposed change, adding a Mode of Applicability for the Rod Position Indication System, is consistent with the manner in which this issue is addressed by the Improved Technical Specifications and is consistent with the Zion submittal to adopt the Improved Technical Specifications. l Attachment C contains an Evaluation of Signi5 cant Hazards Considerations which concludes i that the proposed changes will not 1) Significantly increase the probability of occurrence or consequences of any accident previously evaluated,2) Create the possibility of a new or different kind of accident from those previously analyzed, or 3) Significantly reduce a margin of safety.

Attachment D contains an Environmental Assessment Statement which concludes that since the proposed changes do not involve a significant hazards consideration, a significant change in the types or amounts of effluents that may be released off-site, or a significant increase in individual or occupational radiation exposure, no environmental impact statement need be prepared in conjunction with issuance of a license amendment incorporating these proposed changes.

SCHEDULE REQUIREMENTS This amendment is required prior to completion of the Z2R14, Zion Unit 2 refueling outage.

Rod Position Indicator Channels are required to be calibrated whenever the reactor vessel head is removed and will require calibration following this outage. The Rod Position Indicator Channel calibration will require rod withdrawal as part of the calibration. The estimated date for implementation of this LAR is November 4,1996, l

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