ML20198S483

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Safety Evaluation Supporting Amend 188 to License DPR-40
ML20198S483
Person / Time
Site: Fort Calhoun Omaha Public Power District icon.png
Issue date: 12/31/1998
From:
NRC (Affiliation Not Assigned)
To:
Shared Package
ML20198S447 List:
References
NUDOCS 9901110338
Download: ML20198S483 (6)


Text

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-p k UNITED STATES c ,- g } NUCLEAR REGULATORY COMMISSION WASHINGTON, D.C. 30866 0001

. $ l l *****p SAFETY EVALUATION BY THE OFFICE OF NUCLF.AR REACTOR REGULATION BELATED TO AMENDMENT NO. 188 TO FACILITY OPERATING LICENSE NO. DPR-40 j OMAHA PUBLIC POWER DISTRICT I

FORT CALHOUN STATION. UNIT NO.1 DOCKET NO. 50-285 L l i

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1.0 INTRODUCTION

i By applicati::n dated April 17,1997, Omaha Public Power District (OPPD) requested changes j to the Technical Specifications (Appendix A to Facility Operating License No. DPR-40) for the l c Fort Calhoun Station, Unit No.1. The requested changes would modify some technical l specifications (TS) to be consistent with the Standard TS for Combustion Engineering (CE)

Plants (NUREG-1432); removing or relocating requirements that do not meet the criteria of 10 CFR 50.36(c)(2)(ii), reorganizing existing TS requirements, and revising some TS requirements. Guidance on the proposed changes was developed by the NRC and provided in j the Standard Technical Specifications (STS) for CE Plants, NUREG-1432 (Rev.1), issued on
April 7,1995.

v 2.0 - BACKGROUND  ;

l Section 182a of the Atomic Energy Act (the "Act") requires applicants for nuclear power plant operating licenses to state technical specifications to be included as part of the license. The ,

. Commission's regulatory requirements related to the content of TS are set forth in 10 CFR  !

j 50.36. Section 50.36 of 10 CFR requires that the TS include items in five specific categories, i

including (1) safety limits, limiting safety system settings and limiting control settings; (2) limiting i conditions for operation; (3) surveillance requirements; (4) design features; and (5) i

, administrative controls.

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$ The regulation sets forth four criteria to be used in determining whether a particular matter is required to be included in an LCO, as follows: (1) Installed instrumentation that is used to

' detect, and indicate in the control room, a significant abnormal degradation of the reactor coolant pressure boundary; (2) a process variable, design feature, or operating restriction that

.. is an initial condition of a design basis accident or transient analysis that either assumes the failure of or presents a challenge to the integrity of a fission product barrier; (3) a structure, i- system, or component that is part of the primary success path and which functions or actuates to mitigate a design basis accident or transient that either assumes the failure of or presents a i challenge to the integrity of a fission product barrier; or (4) a structure, system, or component 4 which operating experience or probabilistic safety assessment has shown to be significant to 4

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public health and safety. LCOs and related requirements which fall within or satisfy any of the criteria must be retained in the TS, while those requirements which do not fall within or satisfy these criteria may be relocated to licensee-controlled documents.

3.0 EVALUkTION The discussions below detail the staff's conclusions regarding the proposed modifications to the t Fort Calhoun Station (FCS) Unit 1 TS.

a. TS 2.12. Control Room Systems l The existing TS 2.12 LCO and associated surveillance requirement addresses control' room temperature and air filtration system operability. The proposed change replaces TS 2.12 with two new LCOs,2.12.1 addressing control room air filtration system operability and 2.12.2 addressing the control room air conditioning (A/C) system operability and temperature. The changes ensure that the L' 3 and SR are consistent with the design basis of a fuel handling accident as documented it, e FCS Updated Safety Analysis Report (USAR); two trains of control room air filtration and A/C are now required to be operable when reactor coolant temperature is above 210*F. The control room temperature does not meet any of the criteria of 10 CFR 50.36(c)(2)(ii) for inclusion in the TS because it is not a function or equipment protection feature which is: (1) Installed iristrumentation that is used to detect, and indicate in the control room, a significant abnormal degradation of the reactor coolant pressure boendary; (2) A process variable, design feature, or operating restriction that is an initial condition of a design basis accident or transient analysis that either assumes the failure of or presents a challenge to the integrity of a fission product barrier; (3) A structure, system, or component that is part of the primary success path and which functions or actuates to mitigate a design basis accident or transient that either assumes the failure of or presents a challenge to the integrity of a fission product barrier; nor is it, (4) A structure, system, or component which operating experience or probabilistic safety assessment has shown to be significant to public health and safety. Therefore this requirement is relocated into the USAR, and will be adequately controlled by 10 CFR 50.5g requirements. The control room air filtration and A/C systems meet criterion 3 in that they function to mitigate a design basis accident by maintaining the control loom in a habitable environment and therefore they remain in the TS.

The FCS Probabilistic Risk Assessment (PRA) validates the proposed TS completion times (CT) of the new control room A/C specification; specifically, the 30 day CT for restoring one inoperable train of control room A/C is validated as "non-risk significant." The changes are also consistent with the CE Standard Technial Specification (STS), NUREG-1432 and are

. acceptable.

b. TS 2.1. Reactor Coolant System (RCS)

The existing TS 2.1 LCO and associated surveillance requirement addresses RCS system operability. The proposed change to TS 2.1.1(3) is to include shutdown cooling (SDC)

! requirements when the RCS temperature is below 210*F with fuel in the reactor and the reactor head fully +ensioned. This modification is needed to more accurately control decay heat load and boron concentration which affects shutdown margin (SDM); definitions are i

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.. - ea revised for shutdown conditions to better clarify boron concentration requirements. The existing TS 2.1,1(4) addresses SDC requirements during MODE 5 with fuel in the reactor and the reactor head removed, and is replaced with two new refueling TS (TS 2.8.1(3) and TS 2.8.1(4)). TS 2.8.1(3) and TS 2.8.1(4) differ from TS 2.1.1(3) in that they are applicable as soon as a closure bolt is loosened and two SDC loops are required when water level is less than 23 feet. They are consistent with the CE Standard Technical Specifications (STS),

l NUREG-1432, except that current water level requirements and the current exception allowing l SDC to be inoperable for a limited time are retained. The proposed TS are more restrictive than the current TS and enhance safety during refueling operations by expanding the time of applicability of the TS and more explicitly defining requirements. The staff therefore finds j these changes acceptable.

c. TS 2.6. Containment System
l. The existing TS 2.6(1)c requires containment integrity when the reactor vessel head is

(- removed if refueling boron concentration is below the required limit. If TS 2.6(1)c is not met there are no required actions stipulated other than TS 2.0.1 entry (a shutdown sequence similar to STS 3.0.3), and in the refueling mode TS 2.0.1 entry is ineffective. While TS 2.6(1)a does not require containment integrity when the reactor is in cold shutdown or refueling shutdown, TS 2.6(1)d requires containment integrity regardless of the operating mode for all oositive reactivity additions made by control element assembly (CEA) motion and boron dilution (which is overly conservative). These existing Section 2.6 specifications are proposed to be replaced by new TS 2.8 requirements that eliminate containment integrity requirements when the reactor is in refueling shutdown, and require a refueling SDM of not less than 5 l percent and if it is exceeded specific actions to suspend reactivity additions and restore boron concentration are added. USAR 14.18 indicates that the fuel handling accident does not take l credit for containment isolation, and therefore, requiring containment integrity for fueling handling accidents is unnecessary. Proposed TS 2.8.2(1) requires SDM limits and containment closure requirements, is consistent with the CE Standard Technical Specifications i (STS), NURc.G-1432, and adequately addresses the applicable USAR accident analyses.

Therefore, tnis change is acceptable.

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! d. TS 2.8. Refuelina Operations TS 2.8 is being rewritten to be consistent with the CE Standard Technical Specifications l (STS), NUREG-1432.

The existing "I S 2.8(1), on equipment hatch requirements, is inadequate in that it does not L define what is meant by a properly closed equipment hatch and it requires that all automatic

! containment isolation valves be operable or at least one valve in a line closed, rather than just l those with direct access to the outside atmosphere. The proposed change is to replace TS 2.8(1) with new TS 2.8.2(1), on containment penetrations, which more specifically and correctly requires that closure be initiated by the ventilation isolation actuation signal (VIAS) for

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the containment pressure relief, air sample, and pressure relief, air sample, and purge system l- valves.

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.,.a The existing TS 2.8(2), on containment requirements, is proposed to be replaced by new TS 2.8.2(3)and 2.8.3(5), on VIAS, which more correctly require that VIAS be maintained operable with inputs from the containment atmosphere gaseous and auxiliary building exhaust stack gaseous radiation monitors.

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! The existing TS 2.8(5), on SDC equipment requirements, is proposed to be replaced with new TS 2.8.1(3) and 2.8.1(4), on SDC System requirements, which adds the requirement to maintain at least one SDC loop in operation (with the exception that the loop may be removed from operation for one hour in every eight hour period), and is consistent with the CE STS, l NUREG-1432.

The existing TS 2.8(7), on auxiliary building requirements during fuel handling, is proposed to be replaced by new TS 2.8.3(4), on Spent Fuel Pool Area requirements, which clarifies that the spent fuel pool ventilation system is only required to be in operation for refueling operation in l

the spent fuel pool and not inside containment, and that TS 2.0.1 is not applicable for spent fuel pool operations, consistent with the CE STS, NUREG-1432.

The existing TS 2.8(g), pertains to water level at the top of active fuel. The proposed change is to clarify that the required 23 feet of water is to be above the reactor vessel flange and not the top of active fuel.

Information contained in existing TS 2.8(10), on fuel racks, is proposed to be moved to the l

Design Feature section of the TS.

The existing TS 2.8(11), on spent fuel storage, is being replaced by a new TS 2.8.3(1), on spent fuel assembly storage, which will include the action to immediately move a misloaded fuel assembly, in addition to existing requirements.

The existing TS 2.8(12), on boron concentration in the spent fuel pool, is being replaced by new TS 2.8.3(3), on spent fuel pool boron concentration. The proposed change which will include the requirement to maintain 500 ppm boron concentration in the spent fuel pool whenever unitradiated fuel is stored, in addition to existing requirements.

New TS 2.8.1(1), on boron concentration, will include actions to take if boron concentration is below the refueling limit.

New TS 2.8.3(2), on spent fuel water level, will includo spent fuei pool water level requirements.

The existing TS 2.8(3) on radiation monitoring,2.8(4', on core geometry, and 2.8(6) on communication, do not meet any of the criteria of 10 CFR 50.36(c)(2)(ii) for inclusion in the TS because they are not a functions or equipment protection features which are: (1) installed l

instrumentation that is used to detect, and indicate in the control room, a significant abnormal i degradation of the reactor coolant pressure boundary; (2) a process variable, design feature, or operating restriction that is an initial condition of a design basis accident or transient snalysis that either assumes the failure of or presents a challenge to the integrity of a fission l'

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5-product barrier; (3) a structure, system, or component that is part of the primary success path and which functions or actuates to mitigate a design basis accident or transient that either assumes the failure of or presents a challenge to the integrity of a fission product barrier, nor are they, (4) etpctures, systems, or components which operating experience or probabilistic safety assessment has shown to be significant to public health and safety. Therefore these requirements are relocated into the USAR, and will be adequately controlled by 10 CFR 50.5g requirements. In addition, administrative requirements on the movement of irradiated fuel are moved to the Bases.

The above changes are consistent with the CE STS, NUREG-1432, and enhance safety by more clearly and precisely presenting TS requirements and are therefore acceptable.

e. TS 3.1. Table 3-3. Surveillance Reauirements Changes to the surveillance requirements (SRs) listed in Table 3-3 are made in conjunction with the above TS changes. A SR has been added to verify the operability of the control room

- A/C system required by TS 2.12, and replaces the SR on the control room thermometer. SRs have been added to verify the status of: containment penetrations during refueling operations, SDC loops, refueling water level, and spent fuel pool water level, in accordance with NUREG-1432 and enhance safety by confirming equipment operability. Some SR frequencies verifying boron concentration have been modified slightly to conform with NUREG-1432 requirements with no effect on safuA in addition, editorial changes in presentation have been made (i.e.,

from "7 days" to "W"ist weekly). The SR verifying spent fuel enrichment has been moved from TS 2.8 to TS 3.2, Table 3-5, consistent with the NUREG-1432 location. Overall these changes enhance safety and are therefore acceptable.

f. Definitions in addition to some editorial changes to the definitions, the definition of Refueling Operation has been revised to be consistent with the changes made herein to the current TS, with no impact on safety. Editorial changes have been made to the definitions of Cold Shutdown Condition, Refueling Shutdown Condition, The Refueling Boron Concentration, Plant Operating Cycle, in Operation, Core Alteration, and Axial Shape Index.
g. Conclusion

. The staff has concluded that the above changes are consistent with 10 CFR 50.36 and the model technical specifications provided in the CE STS, NUREG-1432. Therefore, the staff finds these changes acceptable.

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4.0 STATE CONSULTATION

In accordance with the Commission's regulations, the Nebraska State official was notified of the proposed issuance of the amendment. The State official had no comments.

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5.0 ENVIRONMENTAL CONSIDERATION

The amendment changes a requirement with respect to installation or use of a facility component located within the restricted area as defined in 10 CFR Part 20 and changes surveillance requirements. The NRC staff has determined that the amendment invohies no significant increase in the amounts, and no significant change in the types, of any effluents that may be rel eased offsite, and that there is no significant increase in Individual or cumulative occupational radiation exposure. The Commission has previously issued a proposed finding that the amendment involves no significant hazards consideration, and there has been no public comment on such finding (62 FR 30639). Accordingly, the amendment meets the eligibility criteria for categorical exclusion set forth in 10 CFR 51.22(c)(9). Pursuant to 10 CFR 51.22(b) no environmental impact statement or environmental assessment need be prepared in connection with the issuance of the amendment.

6.0 CONCLUSION

j The Commission bus concluded, based on the considerations discussed above, that: (1) there is reasonable assurance that the health and safety of the public will not be endangered by operation in the proposed manner, (2) such activities will be conducted in compliance with the Commission's regulations, and (3) the issuance of the amendment will not be inimical to the l common defense and secunty or to the health and safety of the public.

Principal Contributor: T. Tjader Date: December 31, 1998 j l

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