ML20203C270
| ML20203C270 | |
| Person / Time | |
|---|---|
| Site: | Davis Besse  |
| Issue date: | 12/02/1997 |
| From: | NRC (Affiliation Not Assigned) |
| To: | |
| Shared Package | |
| ML20203C155 | List: |
| References | |
| NUDOCS 9712150269 | |
| Download: ML20203C270 (8) | |
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UNITED STATES
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,j NUCLEAR REGULATORY COMMISSION i
WASHINGTON D.C. enmaa anni gs,*****/
SAFETY EVALVATION BY THE OFFICE OF NUCLEA*4 REACTOR REGULATION RELATED TO AMENDMENT NO. 216 TO FACILITI OPERATING LICEf.SE NO. NPF-3 TOLEDO EDISON COMPANY CENTERIOR SERVICE COMPANY MQ THE CLEVELAND ELECTRIC ILLUMINATING COMPANY DAVIS-BESSE NUCLEAR POWER STATION. UV T NO.___1 DOCKET NO. 50-343
1.0 INTRODUCTION
By letter dated January 20, 1997, Toledo Edison Company, Centerior Service Company, and lhe Cleveland Electric Illuminating Company (the licensees),
submitted a request for changes to the Davis-Besse Nuclear Powe Station (DBNPS), Unit No.1, Technical Specifications (TSs).
The proposed amendment would c: vise TS Section 3/4.5.2, " Emergency Core 2 280*F," TS Section 3/4.5.3, Cooling Systems, ECCS Subsyst sms - T ' Subsystems - T,y <
"EmergencyCoreCoolingSystems,ECC$y 280'F," and TS Section 3/4.7, " Plant Systems." Several surveillance in ervals would be changed from 18 months to once each refueling interval.
2.0 BACKGROUND
Improved reactor fuels allow licensees to consider e', increase in the duration of the fuel cycle for their facilities.
The staff bc reviewed requests for individual plants to modify surveillance intervals to be compatible with a 24-month fuel cycle.
The NRC issued Generic Letter (GL) 91-04, " Changes in Technical Specification Surveillance Intervals to Accommodate a 24-Month Fuel Cycle," on April 2,1991, to provide generic guidance to licensees for preparing such license amendment requests.
TSs that specify an 18-month surveillance interval could be changed to state that these surveillances are to be performed once per refueling interval. The notation for surveillance intervals would then be changed to include the definition of a " Refueling Interval" with the existing "R" notation for surveillances that are generally performed during a refueling outage.
The frequency for the interval indicated by this notation would also be changed from 18 months to "at least once every 24 months." The provision to extend surveillances by 25 percent of the specified interval would extend the time limit for completing these surveillances from the existing limit of 22.5 months to a maximum of 30 months.
ENCLOSURE 2 9712150269 971202 PDR ADOCK 05000346 P
4 s
Licensees must address -instrument drift when proposing an increase in the surveillance interval for calibrating instruments that perform safety functivos including providing the capability for safe shutdown.
The effect of the increased calibration interval on instrument errors must be addressed because instrument errors caused by drift were considered when determining safety system setpoints and when performing safety analyses.
For other-18-month surveillances, licensees should evaluate the effect on safety of the change in surveillance intervals to accommodate a 24-month fuel.
cycle. This evaluation should support a conclusion that the effect on safety is small.
In additian, licensees should confirm that historical maintenance and surveillance data do not invalidate this conclusion.
Licensees should confirm that the performance of surveillances at the bounding surveillance interval limit provided to accommodate a 24-month fuel cycle would not invalidate any assumption in the plant licensing basis, in consideration of these confirmations, the licensees need not quantify the effect of the change in surveillance intervals on the availability of individual systems or components.
3.0 EVALUATION This license amendment request will extend surveillance testing intervals from every 18 months to each refueling interval.
The licensees propose replacing "at least once per 18 months" with "at least once each REFUELING INTERVAL" for the TSs described below.
The proposed changes allow the continued application of TS 4.0.2.
This TS allcws surveillance intervals to be increased up to 25 percent on a nonroutine basis (30 months) in accordance with the GL, A paragraph was added (Amendment 213, dated February 10,1997) to TS Bases 4.0.2, consistent with GL 91-04, that ensures that surveillances are performed in an operational mode consistent with safe plant operation.
This TS Bases section already included clarification that the allowable tolerance not be used as a convenience to repeatedly schedule the performance of surveillances at the allowable tolerance limit.
The licensees performed the safety assessment for the proposed changes to the surveillance test intervals in accordance with the GL 91-04 criteria stated above. This assessment entailed reviewing historical maintenance and surveillance test data, performing an evaluation to ensure that a 24-month surveillance test interval would not invalidate any assumption in the plant licensing bases, and determining that the effect on safety is small. Only the period since 1985 was reviewed.
This is most representative of current operating conditions since many changes occurred after the loss of feedwater event-in 1985. This period includes five refueling outages and four operating cycles of test results.
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3.1 TS Section 3/4.5,2. "Emeroency Core Coolino Systems. ECCS Sybsystems - Tm > 280*F" TS surveillance requirement (SR) 4.5.2.d.2.a requires that a visual inspection of the containment emergency sump be conducted at least once per 18 months.
This inspection must verify that the subsystem suction inlets are not restricted by debris and that the sump components show no evidence of structural distress or corrosion. SR 4.5.2.e requires that, at least once per 18 months, the licensees verify that each automatic valve in the ECCS flow path actuates to its correct position on a safety injection test signal, and verify that each high pressure injection (HPI) and low pressure injection (LPI) pump starts automatically upon receipt of a Safety Features Actuation System 'SFAS) test signal.
SR 4.5.2.g.2 requires that, at least once per 18 months,.he licensees verify the correct position of each mechanical position stop for valves DH-14A and DH-148.
The function of the ECCS is to mitigate the consequences of breaks of the reactor coolant system (ftCS) pressure boundary which result in a loss of reactor coolant greater than the makeup system can handle.
The operability of the ECCS subsystems with T 2 280*F ensures that sufficient emergency core cooling will be available M the event of a loss of coolant accident (LOCA) coincident with a loss of one subsystem through any single failure.
Each ECCS subsystem also provides long-term core cooling capability during accident recovery.
The staff reviewed the proposed changes and the licensing basis.
In addition to the license and TSs, the licensing basis includes the Updated Safety Analysis Report (USAR), Section 6.3, " Emergency Core Cooling System," and Regulatory Guide (RG) 1.82, " Sumps for Emergency Core Cooling and Containment Spray Systems."
The licensees determined that during the period since 1985, which includes five refueling outages and four operating cycles, the results of all surveillance tests were acceptable, with one exception which is included in the following maintenance discussion.
The licensees also reviewed maintenance records related to these surveillance requirements.
This review identified failures and degradation, including problems with pumps, valves, and breakers.
Each of these concerns was evaluated.
Corrective actions included design changes and part and component replacement.
The licensees determined that these concerns were not attributable to the fuel cycle length.
The licensees concluded that, based on the results of the maintenance and surveillance review, the change to a 24-month fuel cycle was acceptable.
In addition, the licensees concluded that the licensing basis would not be invalidated by increasing the surveillance interval; and that the impact on safety would be small.
Further, the licensees determined that it would be acceptable to continue with the application of TS 4.0.2 on a nonroutine basis.
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The staff determined that all actions specified in the GL were completed.
The effect on safety would be small, historical data does not contradict this conclusion, and no assumptions in the plant-licensing basis would be invalidated. Therefore, this change is acceptable.
3.2 LS Section 3/4.5.3. "Emeroency Core Coclina Systems. ECCS Subsystems
_.lg < 280*F" 280*F, TS 3.5.3 only requires one ECCS subsystem to be operable.
With T@e< failure criterion is not considered due to the stable reactivity The si condition of the reactor and the limited cooling requirements.
TS SR 4.5.3 requires that, "The ECCS subsystems shall be demonstrated OPERABLE per the applicable Surveillance Requirements of 4.5.2."
Therefore, the licensing basis, surveillance test result, maintenance record, and TS 4.0.2 reviews for TS Section 3/4.5.2 are also applicable to this section.
Regarding TS Section 3/4.5.2 discussed in Section 3.1 above, the licensees concluded that, based on the results of the maintenance and surveillance review, the change to a 24-month fuel cycle was acceptable.
In addition, the licensees concluded that the licensing basis would not be invalidated by increasing the surveillance interval, that the impact on safety would be small, and that continued use of TS 4.0.2 on a nonroutine basis would be acceptable.
The staff determined that these conclusions are also applicable to TS Section 3/4.5.3. All actions s)ecified in the GL were completed.
The effect on safety would :ee mil, listorical data does not contradict this conclusion, and no assumptions in the plant licensing basis would be invalidated.
Therefore, this change is acceptable.
3.3 TS Section 3/4.7.1.2. " Plant Systems. Auxiliary Feedwater System" TS SR 4.7.1.2.1.c requires that each auxiliary feedwater (AFW) train shall be demonstrated operable at least once per 18 months by:
(1) verifying each automatic valve actuates to its correct position on a Steam and Feedwater Rupture Control System (SFRCS) actuation test signal; (2) verifying each pump.
starts automatically upon receipt of an SFRCS test signal; and (3) verifying that there is a flow path from each AFW pump to both steam generators (SGs).
The function of the AFW system is to provide feedwater to the SGs when the main feedwater pumps are not available. The AFW pumps can be used to rer.ove decay heat while shutting the unit down until the decay heat removal system can be placed in service. The AFW system includes two steam turNne-driven pumps, condensate storage tanks, feedwater and steam piping, valse;, and
-associated instrumentation and controls.
The staff reviewed the proposed changes and the licensing basis.
In addition to-the license and the TSs, the licensing basis includes USAR Section 7.4.1.3,
" Steam and Feedwater Line Rupture Control System (SFRCS)," Section 9.2.7,
" Auxiliary Feedwater System," and Section 15.2.8, " Loss of Normal Feedwater."
e
- The licensees determined that during the period since 1985, which includes i
five refueling outages and four operating cycles, the results of all surveillance tests were acceptable.
The licensees also reviewed maintenance j
records related to this SR. This review identified several failures, including problems with pumps, valves, and associated components.
Each of these concerns was evaluated. Corrective actions included part and component repair and replacement, personnel training, hat these concerns were notmore frequen design changes.
The licensees determined t attributable to the fuel cycle length.
The licensees concluded that, based on the results of the maintenance and surveillance review, the change to a 24-month fuel cycle was acceptable.
In addition, the licensees concluded that the licensing basis would not be invalidated by increasing the surveillance '.aterval, and that the impact on t
safety would be small.
Further, the licensees determined that it would be acceptable to continue with the application of TS 4.0.2 on j nonroutine basis.
The staff determined that all actions specified in the GL were completed.
The effect on safety would be set 11, historical data does not contradict this conclesien, and no assumptions in the plant licensing basis would be invalidated.
Therefore, this change is acceptable.
3.4 TS Section 3/4.7.i.7. " Plant Systems. Motor Driven Feedwater Pumo System" TS SR 4.7.1.7.d requires that the motor driven feedwater pump (MDFP) and flow paths to the AFW system be demonstrated operable at least once per 18 months by:
(1) verifying that there is a flow path between the MDFP system and the AFW system by pumping water from the condensate storage tanks to the SGs; (2) verifying proper operation of the MDFP lube oil interlocks; and (3) verifying propar operation of manual valves by shifting the MDFP between the main teedwr'.f system and the AFW system.
The function of the MDFP system is to provide feedwater to the SGs during norual r.tartup and shutdown.
The system also provides backup feedwater to the SGs in the event of a loss of both auxiliary and main feedwater.
Though the MDFP is nonsafety-related, it does provide a diverse means for supplying feeddater to the SGs, backing up the safety-related AFW system.
Tht staff reviewed the proposed changes and the licensing basis, in addition to the license and the TSs, the licensing basis includes USAR Section 9.2.8,
" Motor Driven feedwater Pump," and Section 10.4.7.2, "Condensat., and Feedwater System."
Iha licenstes determined that during the period since 1985, which includes five refueling outages and four operating cycles, the results of all surveillance tests were acce) table.
However, the licensees did not review the results of SR 4.7.1.7 d.1, witch requires verification that th(.re is a flow path between the MDFP system and the AFW system. They stated that this reqJirement only verifies the existence of a flow path, and not the verificstion of automatic valve actuaticn or MDFP flow rate.
The staff has
o reviewed this exception and finds it acceptable sir.e the proper performance of the subject components is verified by other 3Rs.
The licensees reviewed maintenance records related to all sections of SR 4.7.1.7.d.
No failures or degradations were identified.
The licensees concluded that, based on the results of the maintenance and surveillance review, the change to a 24-month fuel cycle was acceptable.
In addition, the licensees concluded that the licensing basis would not be invalidated by increasing the surveillance interval, and that the impact on safety would be small.
Further, the licensees determined that it would be acceptable to continue with the application of TS 4.0.2 on a nonroutine basis.
The staff determined that all actions specified in the Gl. were completed.
The effect on safety would be small, historical data does not contradict this conclusion, and no assumptions in the plant licensing basis would be invalidated.
Therefore, this change is acceptable.
3.5 JS Secticn 3/4.7.3. " Plant Systems. Component Coollnu Watet System" 15 SR 4.7.3.1.b requires that each component cooling water loop shall be demonstrated oporable at least once per 18 months, during shutdown, by verifying that each eutomatic valve in the flow path actuates to its correct position a d each component cooling water emergency pump starts automatically on an SFAS test signal.
The component cooling water (CCW) system provides cooling water to reactor auxiliaries and the ECCS components.
The CCW c.mponents are designed to remove the maximum heat load during normal operation with 85'F service water, and the maximum heat load from ECCS components during accident conditions with service water at ultimatt heat sink conditions.
The staff reviewed the proposed changes ano the licensing basis.
In addition to the license and the TSs the licensing basis includes USAR Section 9.2.2,
" Component Cooling Water System."
The licensees determined that during the period since 1985, which includes five refueling outages and four operatin cycles, only one failure occurred during surveillance testing.
A CCW valve failed to stroke due to a broken air line.
The air line and associated fittings were replaced and retested, with satisfactory results, and no other problems have occurred. The licensees determined that this failure was not attributable to fuel cycle length.
The licensees reviewed maintenance records related to this SR.
Two, mblems were identified, a pump motor performance degradation and a potential valve performance issue. The pump motor was satisfactorily repaired and a valve design modification was successfully implemented.
These problems were not related to fuel cycle length.
The licensees concluded that, based on the results o" the maintenance and surveillance review, the change to a 24-month fuel cycle was acceptable.
In
o 1-9 addition, the licensees concluded that the licensing basis would not be invalidated by increasing the surveillance interval, and that the impact on safety would be small.
Further, the licensees determired that it would be acceptable te continue with the application of TS 4.0.2 on a nonroutine basis.
The staff determined that all actions specified in the GL were completed.
The effect on safety would be small, historical data does not contradict this conclusion, and no assumptions in the plant licensing basis would be invalidated. Therefore, this change is acceptable.
3.6 TS Section 3/4.7.4. " Plant Systems. Service Water System" TS SR 4.7.4.1.b requires each service water loop to be demonstrated operable at least once per 18 months, during shutdown, by verifying that each automatic valve in the flow path actuates to its correct position, and each service water emergency pump starts automatically, on an SFAS test signal.
During normal operations, the service water system (SWS) supplies cooling water to the cox.ponent cooling heat exchangers, the containment air coolers, and the cooling water heat exchangers in the turbine building.
During an emergency, the SWS provides redundant cooling to the engineered safety features components.
One pump provides adequate cooling during an emergency, though three 100%-capacity pumps are available.
The staff reviewed the proposed changes and the licensing basis.
In addition to the license and the TSs. the licensing basis includes USAR Section 9.2.1,
" Service Water System."
The licensees determined that during the period since 1985, which includes five refueling outages and four operating cycles, only one failure occurred during surveillance testing. A valve failed to stroke open.
The licensees evaluated this failure and determined that it was a valve design issue.
The issue was resolved by modifying the valve design.
This failure was not related to fuel cycle length.
The licensees also reviewed maintenance records related to this SR.
This review identified several failures and two deficiencies, including problems with pumps, valves, and breakers.
Each of these concerns was evaluated.
Corrective actions included periodic valve exercising and component adjustment, repair, and/or replacement.
Tne licensees determined that these concerns were not attributable to the fuel cycle length.
The licensees concluded that, based on the results of the maintenance and surveillance review, the change to a 24-month fuel cycle was acceptable.
In addition, the licensees concluded that the licensing basis would not be invalidated by increasing the surveillance interval, and that the impact on safet) would be small, further, the licensees determined that it would be acceptable to continue with the application of TS 4.0.2 on a nonroutine basis.
o O The staff determined that all actions specified in the GL were completed.
The effect on safety would be small, historical data does not contradict this conclusion, and no assumptions in the plant licensing basis would be-invalidated.
Therefore, this change is acceptable.
4.0 STATE CONSULTATION
[
In accordance with the Commission's regulations, the Ohio State official was notified of the proposed issuance of the amendment.
The State official had no courient s.
5.0 ENVIRONMENTAL CONSIDERATION
This 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 or changes a surveillance requirement.
The staff ha.
etermined that the amendment involves no significant increase in the amounts, and no significant change in the types, of any effluent that may be re. eased offsite, and that there is no significant increase in individual or cumulative i
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 11498). 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
i The staff has concleded, 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 pro)osed manner; (2) such activities will be conducted in compliance wit 1 the Commission's regulations; and (3) the issuance of this amendment will not be inimical to the common defense and security or to the health and safety of the public.
Principal Contributor:
A. Hansen Date:
December 2 1997 1
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