ML20095D815
| ML20095D815 | |
| Person / Time | |
|---|---|
| Site: | North Anna  |
| Issue date: | 04/21/1992 |
| From: | Office of Nuclear Reactor Regulation |
| To: | |
| Shared Package | |
| ML20095D808 | List: |
| References | |
| NUDOCS 9204270226 | |
| Download: ML20095D815 (3) | |
Text
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SAFETY EVALUATION BY THE OFFICE OF HUCLEAR REACTOR REGULATION RELATED TO AMENDMENT NOS.156 AND 138 TO FACILITY OPERATING LICENSE N05. NPF-4 AND NPF-7 VIRG1HIA ELECTRIC AND POWER COMPANY OLD DOMINION ELECTRIC COOPERATIVE NORTH ANNA POWER STATION, UNITS NO. 1 AND NO. 2 DOCKET NOS. 50-338 AND 50-339
1.0 INTRODUCTION
By letter dated April 16, 1991, the Virginia Electric and Power Company (the licensee) proposed changes to the Technical Specifications (TS) for the North Anna Power Station, Units No. I and No. 2 (NA-1&2). The propu.ed changes would clarify the emergency (power supplies which must be operable in mode 5 (coldAlso shutdown) and mode 6 refueling).
applicability section of the TS the case of moving irradiated fuel assemblies or any loads over irradiated fuel assemblies with the reactor defueled.
Finally, the proposed changes would remove the requirement to establish containment integrity if a bus is lost while shut down.
A discussion of the proposed changes and the staff's evaluation is provided below.
2.0 DISCUSSION 2.1 TS 3.8.1.2. Electrical power Systems:
Shutdown-LCO The applicability section of the NA-1&2 TS 3.8.1.2 would be expanded by adding movement of irradiated fuel assemblies or any loads over irradiated fuel assemblies with no fuel assemblies in the reactor. This change would ensure that power is available to systems necessary to recover from a fuel handling accident. Therefore, the licensee would be better equipped to cope Also, Action "a" of TS 3.8.1.2 would be with a fuel handling accident.
changed to stop movement of irradiated fuel assemblies or loads over irradiated fuel assemblies if the TS can not be met. This proposed change is consistent with the Standard Technical Specifications (STS) wording with the exception of the requirement to depressurize and vent the reactor coolant systeni(RCS).
The NA-1&2 TS 3.4.9.3 LCO provides this action if the power-operated relief valves (PORVs) become inoperable. Therefore, this action in TS 3.8.1.2 would be In addition, this change is consistent with TS redundant and is not necessary.
approved by the NRC for other facilities.
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-2 2.2 TSs 3.4.8.2.2 and 3.4.8.2.4:
Electrical power Systems /A.C. and D.C.
Distribution-Shutdown LCO TSs 3.4.8.2.2 and 3.4.8.2.4 were combined and rewritten to designate the equipment'and busses for two complete trains (H and J) of the A.C. and D.C.
sources. The current NA-1&? TS allow busses from different trains (H and J) to be used for recuired busses and equipment. This proposed change would specifically designate the NL-1&2 TS 3.8.2.2 LCO as requiring, as a minimum, one complete train (J or H) of the A.C. and D.C. busses to be operable.
This change is more conservative than the current NA-182 TS and will reduce the probability and consequences of accidents in modes S and 6.
Stating the number and type of components required is consistent with the wording of the NA-1&2 TS LCOs 3.8.2.1 knd 3.8.2.3.
The proposed changes would also require that the vital busses be powered from the inverters connected to the D.C. busses.
This operability requirement for the inverters is consistent with the STS.
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_ proposed changes would also allow using(the swing chargers w en a normaswing cha charger is out of' service. The spares Class IE chargers.
In addition, the applicability section of the proposed TS would be changed to include the movement of irradiated fuel assemblies or loads over irradiated fuel assemblies with no fuel assemblies in the reactor vessel.
The current action section for the NA-1&2 TS 3.4.8.2.2 and 3.4.8.2.4 requires that containment integrity be established within 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> if a required bus is lost. The proposed change would delete this requirement and is in conformance with the Westinghouse STS, Revision 4.
The licensee would retain the requirements for containment closure during irridated fuel movement (TS 3/4.9.4) when residual heat removal is lost in mode 6 (TSs 3/4.9.8.1 and 3/4.9.8.2) and when the containment purge and exhaust system is lost in mode 6 (TS 3/4.9.9). However, work in the fuel building may be in progress and the potential for a release to.the environment is not precluded.
Therefore, if the A.C. and D.C. distribution LCO cannot be met, then any operations involving core alterations, positive reactivity changes, movement of irradiated fuel assemblies, and movement of loads over irradiated fuel assemblies would be stopped.
Finally, combining the current NA-1&2 TSs 3.4.8.2.2 and 3.4.8.2.4 into a revised -TS 3.4.8.2.2 would eliminate the current NA-1&2 TS 3.4.8.2.4.
3.0 EVALUATION The proposed changes would clarify the NA-1&2 TS and provide consistency with the STS.
In addition, the. changes would clarify the emergency power supplies which must be available in modes 5 and 6 and add to the TS LCOs the case of moving irradiated fuel assemblies or loads over irradiated fuel. assemblies-with the reactor defueled.- These changes are more conservative than the current NA-1&2 TS and would better allow the licensee to cope with a fuel.
handling accident and therefore reduce the probability and consequences of an accident in modes 5 and 6.
Also, the proposed change to delete the current requirement to establish containment integrity if an electrical bus is lost is consistent with the STS. Finally, required containment integrity in modes 5 and 6 is retained in the current NA-1&2 TS. Based on all of the above, the staff finds the proposed changes to be acceptable.
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3.0 STATE CONSULTATION
in accordance with the_ Comission's regulations, the Virginia State official' was notified of-the proposed issuance of the amendments. The State official had no - coment.
4.0 ENVIRONMENTAL CONSIDERATION
- These amendments change 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-amendments involve no significant increase in the amounts, and no significant change in the types, of any effluents'that may be released offsite, and that there is no significant increase in individual or cumulative occupational
. radiation exposure. The Comission has previously issued a proposed finding that the amendments involve no significant hazards consideration and there has-been no public coninent on such finding (56 FR 22481). Accordingly, these amendments meet 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 stetement or environmental assessment need be prepared in conrection with the issuance of these amendments.
5.0 CONCLUSION
The Comission.has concluded, based on the considerations discussed above, that:
not be endangered by; operation in the proposed manner, (2) y of the (1) there is reasonable assurance that the health and safetsuch activities will
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be conducted in compliance with the.Comission's regulations, and (3) the issuance of the amendments will not be inimical to the coninon defense and security or to the. health and safety of the public.
E Principal Contributor:
L. Engle Date:
April 21,1992 W