ML20096C217

Application for Amend to License NPF-3,changing TS 3/4.1.3.1 Re Group Height - Safety & Regulating Rod Groups & TS 3/4.1.3.3 Re Position Indicator Channels to Clarify Proper Progression of TS 3/4.1.3.1 Action Statement

ML20096C217
Person / Time
Site:	Davis Besse
Issue date:	04/30/1992
From:	Shelton D CENTERIOR ENERGY
To:
Shared Package
ML20096C205	List: ML20096C200 ML20096C217 ML20096C232
References
2028, NUDOCS 9205130229
Download: ML20096C217 (8)

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, Docket Number 50-346 License Number NPP-3 S.erial Number 2028 Enclosure

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APPLICATION FOR AMENDMENT TO l I

FACILITY OPERATIt;G LICENSE NUMBER NPF-3 DAVIS-BESSE NUCLEAR POVER STATION UNIT NUMBER 1 Attached are requested changes to the Davis-Besse Nuclear Fover Station, Unit Number 1 Facility Operating License Nutrber NPF-3. Also l included is the Safcty Assessment and Significant Hazards Consideration.

The proposed changes (submitted under cover letter Serial Number 2028) -j concern:

Appendix A, Technical Specification 3/4.1.3.1, Reactivity Control Systems, Group Height - Safety and Regulating Rod Groups  !

Appendix A, Technical Specification 3/4.1.3.3, Reactivity Control.

Systems, Position Indicator Channels 1

I For: D. C. Shelton Vice President - Nuclear By: _/ I' f

T . jf . yers Dh e tor - Technical Services Sworn and Subscribed before me this 30th day of April, 1992.

K$/h 6 IAt?L Notary P/.1611c, State 6f Ohio EVELYNL DRESS NOTARY PUEUC,STATEOFOHIO MyConurmaEpirosJiy28,24 9205130229 920430 PDR ADOCK 05000346

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, Docket' Number 50-346'

+ "+- License Number NPP-3

Serial Number 2028 Enclosure-Page 2 The following information is provided to. _ port issuance of the requested _ changes to the Davis-Besse Nuclear Power Station (DBNPS),

Unit Number 1 Operrting-License Number NPP-3,: Appendix A, Technical

- Specification (TS) 3/4 l.3.1, Group Height - Refety and Regulating Rod Groups, and 3/4.1.3.3, Position Indicator Channels.

A. Time Required to-Implement inil.s change is to be implemented within 90 days after the NRC issuance of the License Amendment, B. Reason IEr Change (License *ndment Request Uumber 91-0020):

This change is being proposed to remove unwarranted restrictions in the Technical Specifications ubich have resulted in delays in plant-startups and to also clarify portions-of Technical Specifications 3/4.1.3.1 and 3/4.1.3.3.

This request-proposes changes to the_TS 3/4.1.3.1_ Action statement- -

'to clarify the proper progression of tha Action. This-request also proposes-to revise the TS-3.1.3.3 Action statement as follows:-

Revising Action 3.1.3.3.a.2 by stating that Startup and Power Operation may continuel Adding references to Specifications 3.1.3.5

-and 3.1.3.9 to Action 3.1.3.3.a.2.c; Revising' Action 3.1.3.3.b to clarify that the action applies for the situation of more than one relative ~ position indicator channel per control-rod group inoperable, to clarify that the requirements of either^ Action 3.1.3.3.a.1 or 3.1.3.3.a.2 must-be met, and to allow-Startup or

-Power Operation to continue provided the absolute position indicator channels are operable for the affected control rods, and; Adding new Action 3.1.3.3.c to state that the provisions of Specification 3.0.4 are not applicable.

- C. Sa'ety:AssessmentahdSignificantHazardsConsideration: See Attachment.

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Docket Number 50-346 License Number NPF-3 S.erial Number 2028 Attachment Page 1=

SAFETY ASSESSMENT AND SIGNIFICANT HAZARDS CONSIrPRATION TITLE:

Revision of Technical Specification (TS) 3/4.1.3.1, Reactivity Control Systems, Group Height --Safety and Regulating Rod Groups, and 3/4.1.3.3, Reactivity Control Systems, Position Indicator Channels.

DESCRIPTION:

The purpose of the proposed change is to modify the Davis-Besse Nuclear Power Station (DBNPS) Operating License NPF-3, Appendix A Technical Specifications. The proposed chanFes (see attached marked up Technical Specifications) revise TS 3/4.1.3.1, Group Height - Safety and Regulating Rod Groups, and 3/4.1.3.3, Posi; ion Indicator Channels.

This request proposes changes to the TS 3/4.1.3.1 Action statement to clarify the proper progression of the Action. This request also proposes to revise the TS 3.1.3.3 Action statement as follows:

. Revising Actions 3.1.3.3.a.2 by stating that Startup and Power Operation may continue; Adding references to Specifications 3.1.3.5 and 3.1.3.9 I to Action 3.1.3.3.a.2.cl Revising Action 3.1.3.3.b to clarify that the action applies for the situation of more than one relative position indicator' channel per control rod group inoperab~1e, to clarify that the

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requirements of either Action 3.1.3.3.a.1 or 3. 3.3.a.2 must be met, and to allow Startup or Power Operation to continue provided the absolute position indicator channels are OPERABLE for-the affected control rods, and; Adding new Action 3.1.3.3.c to state that the provi.sions of Specification 3.0.4 are not applicable.

SYSTEMS, COMPONENTS, AND ACTIVITIES-AFFECTED:

Control Rod Drive Control System, including Control Rod Assembly Absolute Position Indication and Control Rod Ascembly Relative Position Indication.

SAFETY FUNCTIONS OF THE AFFECTED SYSTEMS, COMPONENTS, AND ACTIVITIES:

The control rod drive control system (CRDCS) consists of three basic components: (1) motor conttol system, (2) system logic, and (3) trip l

- circuitry. Updated Safety Analysis Report _(USAR) Section 7.4.1.1 i discusses-that the control portion of the CRDCS is not required for I safety. -Updated Safety Analysis Report Section 7.7.2.3, Control Rod Drive Control System (CRDCS), further. states that.only the-CRDCS trip circuitry performs a safety function and that the other portions of the CRDCS are not required to function in any safety analysis.

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, Docket Number 50-346 License Number NPF '

Serial Number 2028_

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. Attachment

~ Page-2 The CRDCS'- Vithout Trip' Portion la described in USAR Section 7.7.1.3.

Major'subsysteme of the' system logic include the operator's control panel,-control rod =asse'bly m position indication, automatic control

- logic. functions and system monitoring functions. The CRDCS provides for withdrawal and insertion of groups of control rod assemblies (CRAs), or " control rod groups" to produce the desired reactor power output.

Updated Safety Analysis Report Section 7.7.1,3.2, Equipment Description, describes the available indication to determine the control' rod. assembly positions. Two methods of position indication are described: abselute position indicati_on (API) and relative position indication (RPI).

The primarv mear.s of providing position indication of a control rod assembly i. the API. The absolute position transducer consists of a series of ragnetically operated reed switches mounted in a tube i

parallel to the Control Rod Drive Mechanism (CRDM) motor tube L extension. Switch contacts close when a permanent magnet mounted on the upper end of the CRA leadscrev extension comes neat. As the leadscrev '(and the ; control rod assembly) moves, the switches operate sequentially, producing'a' voltage proportional to position.

The secondary means of providing position indication.of a control rod assembly is tiie' RPI. The relative position transducer is a small pulse stepping motor driven from the power supply for the control rod drive motor. The pulse-stepping motor drives a potentiometer whose output L

- voltage provides relative position indication. Relative position l' _ indication informs the operator what the expected position of the control rod assembly __should be. However, this is r.ot as direct a method of determining control. rod assembly position as is the absolute position indication, which involves the actuation-or a switch at a known location.

l Another means of providing position indication of a control' rod D assembly are the position =referance indicators (" zone reference lights") refesred to in TS Action 3.1.3.3. -2. The zone reference

- light indication-is developed from reed switches (similar to those used in the API system) located at discrete positions corresponding to 0,

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L 25, 50,.75, and-lCO preent- vithdrawn f rom the co*e.

I L The control rod position indication panel in the control room displays enh-control rod assembly position. Both relative and absolute control-rod assembly positions can.be'shown on the same meter through switching

, via the use of the position indication select switch.

The zone reference lights are located on a local panel (outside the control room).

--In summary, the function of the position indicators is to provide the means for determining control rod assembly positions _and thereby ensure compliance with the control rod alignment and insertion limits (Reference TS Bases 3/4.1.3, Movable Control Assemblies). Only the l.

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Docket Number 50-346 License Number MPF-3 Serial Number 2028 Attachment Page 3 separate CRDCS-Trip Portion has a safety function and the position indicators do not have a safety function in any safety analysis.

EFFECTS ON SAFETY:

1 The proposed change to TS 3.1.3.1, adding the word "and" to the end of the first three portions of Action 3.1.3.1.c.2 clarifies that Actions 3.1.3.1.c.2.a. b, and c must be performed with either Actions 3.1.3.1.c.2.d or e. This change is administrative and has no adverse effect on plant safety.

The proposed change to TS 3.1.3.3 adding additional references to TS 3.1.3.5 and 3.1.3.9 to Action 3.1.3.3.a.2.c is a clarification.

Technical Specification 3.1.3.5 requires all safety rods to be fully withdravn. Technical Specification 3.1.3.6 (currently referenced),

requires that the regulating rod groups be positioned within the ateeptchle operating limits for regulating rod positions provided in the Core Operating Limits Report (COLR). Technical Specification 3.1.3.9 requires that the APSR group be within the acceptable operating limits for APSR position specified in the COLR. This change clarifies that TS 3.1.3.5 and 3.1.3.9 remain applicable when in Action 3.1.3.3.a.2, and has no adverse effect on plant safety.

The proposed change to TS 3.1.3.3 revising Action 3.1.2.3.b to add the vords "per control rod group" is a clarification. Action 3.1.3.3.a provides the action to take "vith a maximum of one absolute position indicator channel per control rod group or one relative position indicator channel per control rod group inoperable ..." (emphasis added). Since Action 3.1.3.3.a allows up to one RPI channel per control rod gro.p to be inoperable, the position indicator channels being referred to in Action 3.1.3.3.b address the progression to more than one RPI channel pet control rod group. This changa is a clarification and has no adverse effect on plant safety.

The proposed change to TS 3.1.3.3 revisinr Action 3.1.3.3.b to state that the requirements of either Action 3.1.3.3.a.1 or 3.1.3.3.a.2 must be met, is a clarification. Action 3.1.3.3.b addresses the progression of an increased number of inoperable relative position indicator channels from that of a single inoperable relative position indicator channel per control rod group. Since this is a progression from the situation of a single relative position indicator per control rod group, the requirements of Action 3.1.3.3.a must also be met.

Explicitly stating this requirement clarifies the proper accion to be taken in the event Action 3.1.3.3.b is entered directly. This change is a clarification and has no adverse effect on plant safety.

Technical Specification Action 3.1.3.3.b currently allows operation in Modes 1 and 2 to continue for up to 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> in the event this Action statement is entered. As described above, the proposed change to Action 3.1.3.3.b would allov operation in Modes 1 (Pover Operation) and 2 (Startup) to continue provided the API channels are operable for the associated control rod assemblies. Vitu an RPI channel inoperable, the primary means of position indication fnr the rod is still provided by I

Docket Number-50-346 License Number NPF-3 Serial Number 2028 Attachment Page 4~

the operable API channel, and therefore the requirement to shut down is overly restrictive. The API is a more diro'.t indication since it utilizes fixed switches as a means of deteraining-control rod position, while the RPI utilizes an indirect means of determining control rod position. . Recognition of the API as the more reliable control rod assembly position indicator is reflected in the fact that during normal operation the RPI is reset as necessary to malch the API; therefore, the-API is used as the "knovn" position of a control rod assembly.

Typically, inoperable RPI channels can be restored with the plant undergoing startup (Hode 2) or continued power operation (Mode 1). It should also be noted that the position reference indication required by TS Actions 3.1.3.3.a 2.a and 3.1.3.3.a.2.b provides another means of position indicatiot, in addition to API. Should both the API and RPI be inoperable for tha same control rod assembly, then the shutdown -

requirements of TS 3.0.3 vould apply and shut down from a Hode 1 er Mode 2 condition would be required to be initiated within one hour.

With both-the API and RPI inoperable for the same control rod assembly, startup entry into Mode 2 would be prohibited. Since reliable control rod assembly position indication continues to be provided by the operable API channels and the zone reference lights, and gisen the fact that the rod position indication systems do not perform a safety-related function, this change has no adverse effect on plant safety.

The proposed change ~to TS 3.1.3.3 clarifying Action 3.1.3.3.a.2 by stating that "Startup and Power Operation may continue" in lieu of the present wording " Opera + ion may continue" reflects the proposed change to take-exception to TS 3.0.4. This change is discussed below and has no adverse effect on plant safety.

Technical Specification 3.0.4 states, in part, " Entry into an OPERATIONAL H0DE or' other specified applicability cor.dition shall not be~made unless the conditions of the Limiting condition for Operation are met vithout reliance on provisions contained in the ACTION statements unless otherwise excepted." The proposed change to TS 3.1.3.3 adding a new Action 3.1.3.3.c exempting TS 3.1.3.3 from the

-provisiv s of TS.3.0.4 is in accordance with NRC guidance provided in beneric Letter (GL) 87-09 "Sectior 3.0 and 4.0 of the Standard Technical Specitications (STS) on the Applicability of Limiting Conditions.for Operatiei cnd Surveillance Requirements", dated June 4, 1987. Generic Letter 87-09' states: "For an LCO that has Action Requirements permitting continued operation for an unlimited period of time,-entry into an operational mode or other specified condition of operation should be permitted in accordance with.those Action Requirements." TS 3.0.4 vould unduly restrict plant operatita since conformance to-the Action Requirements provides an acca-table level of safety for.concinued operation. Therefore, the exception to TS 3.0.4 should apply to existing TS Action 3.1.3.3.a which permits continued plant operation. With NRC approval of the proposed change to TS Action 3.1.3.3.b, this Action vill also meet the criterien described in GL 87-09. Therefore, since conformance to the Action requirements establishes an acceptable level of safety for continued plant operation, this change vill have no adverse effect on plant safety.

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-1 Docket-Number 50-346 License Number NPF-3 Serial Number 2028 Attachment Page 5 SIGNIFICANT HAZARDS CONSIDERATION:

The NRC har provided standards in 10CFR30.92(e) for determining whether a significant hazard exists due to a proposed amendment to an operating License for a facility. A proposed amendment to an Operatitig License for'a facility involves no significant hazards it operation c3 the facility in accordance with the proposed changes vould (1) Not involve a significant increase in the probability or consequences of an accident previously evaluated; (2) Not create the possibility of a new or different kind of accident from any racident previously evaluated; or (3) Not involve a significant reduction in a margin of safety.

Toledo Edison has reviewed the proposed change and determined that a significant hazards consideration does not exist because operation of thi Davis-Besse Neelear Power Station, Unit Number 1, in accordance with these changes vouldt la. Not involve a significant increase in the probability of an accident previously evaluated because no Updated Safety Analysis Report accident initiators are affected by the proposed changes.

The proposed change to TS Action 3.1.3.3.b to allow startup and operation in Modes 1 and 2 to continue (provided the conditions of the Action statement are met) has no bearing on experiencing an accident previously evaluated. The remaining proposed changes are clarifications only and have no adverse effect on the probability of experiencing an accident previously evaluated.

Ib. Not _ inv >lve a significant increase in the radiological consequences of an acc$ dent previously evaluated because the proposed' changes do.not invalidate accident conditions o assumptions used in evaluating the radiological consequencer of any accident. The proposed enange to TS Action 3.1.3.3.b to allow startup_and operation in Modes 1 and 2 to continue (provided the conditions of the Action statement are met) does not alter the source term, contain:aent it.olation, or allovable releases, and therefore vill:not increase the radiclogical consequences of a-previously evaluated accident. The re aining changes are clarifications only and have no adverse effect on the consequences of an_ accident previously evaluated.

2a. Not create the possibility of a new kind of accident from any accident previously evaluated because no new types of failures or accident-initiators are introduced by the proposed changes.

-2b. Not create the possibility of a different kind of accident from any' accident previously evaluated because no different accident initiators or failure mechanisms are introduced by the proposed changes.

-3. Not involve a significant reduction in the margin of safety. The ,

proposed change to TS Action 3.1.3.3.b to allov startup and I operation in Modes 1 and 2 to continue (provided the conditions of the Action statement are met) vill not have an adverse effect on margin of safety. Reliable rod position indication vill continue j i

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Docket Number 50-3461 License Number NPF-3 Serial = Number 2028 Attachment-Page 6-:

U -to be:provided. All accident analyses vill remain valid.- The

-remaining changes are clarifications only and.no adverse changes in mergins~ of safety vill cccur.

CONCLUSION -

On the basis of the above, Toledo Edison has determined that the License-Amendment Request does not involve a significant hazards consideration. As the License Amendment Request concerns a proposed change to the Technical Specifications that must be revieved by the NRC, this. License Ansndment Request.does not constitute an unreviewed safety question.

ATTACHMENT

• Attached are the proposed marked-up changes to the Operating License.

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