ML17285A455
| ML17285A455 | |
| Person / Time | |
|---|---|
| Site: | Columbia  |
| Issue date: | 05/02/1989 |
| From: | Office of Nuclear Reactor Regulation |
| To: | |
| Shared Package | |
| ML17285A456 | List: |
| References | |
| NUDOCS 8905150035 | |
| Download: ML17285A455 (4) | |
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UNITED STATES NUCLEAR REGULATORY COMMISSION WASHINGTON, D. C. 20555 SAFETY EVALUATION BY THE OFFICE OF NUCLEAR REACTOR REGULATION REGARDING DENIAL OF AMENDMENT TO FACILITY OPERATING LICENSE NO.
,WASHINGTON NUCLEAR PROJECT NO. 2 DOCKET NO. 50-397
1.0 INTRODUCTION
In a letter dated October 4, 1985 (G02-85-694) the licensee requested an amendment to Facility Operating License No. NPF-21 that would remove technical specification requirements pertaining to the reactor core isolation cooling (RCIC) system.
The licensee argued that previous modifications to the automatic depressurization system (ADS) logic have made the ADS responsive to a wider range of transients and in conjunction with the low pressure emergency core coo1ing systems (ECCS
, the ADS provides a backup to the high pressure core spray (HPCS) systems for high pressure events.
By letter dated December 5, 1985 (G02-85-817) the licensee made two modifications to the amendment application:
to minimize the potential for spurious automatic actuations of the RCIC system, the licensee proposed retaining requirements for the automatic initiation instrumen-tation and its surveillance; and to minimize the potential for RCIC operation to overfill the reactor
- vessel, the licensee proposed retaining the requirements for the RCIC high reactor water level trip instrumentation.
By letter dated August 4, 1986 (G02-86-732) the licensee requested additional page changes to delete references to the operability of the RCIC system.
This final set of changes do not modify the intent or understanding of the original request but are essentially editorial.
- 2. 0 EVALUATION The modifications which the licensee made to the ADS were made in response to the findings of the studies of the TMI accident (NUREG-0892, "Outstanding Issue I.7(9), Modifications to ADS Systems Logic").
The modifications to the ADS provided additional capability for ensuring heat removal at high reactor pressure.
This gets away from total reliance on the RCIC system as the backup to the HPCS system.
On February 6, 1987 the Commission issued for public comment an Interim Policy Statement titled, "Commission Policy Statement on Technical Specification ImprovemeIIts for Nuclear Power Reactors,"
(Federal Re ister 52 FR 3788).
The generai intent was to focus technica1 ~spec>>cat on S905150035 S90502 PDR ADOCK 05000397,'
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requirements on features of a facility that are of controlling importance to safety.
Some reliance was placed on probabilistic risk assessment.
That interim policy statement provided guidance for use by licensees in requesting removal of extraneous license'equirements.
The policy state-ment set forth three criteria that would provide the basis for determining those constraints on design and operation of nuclear power plants that belong in Technical Specifications.
The interim policy.statement went on to declare that, in addition to structures,
- systems, and components captured by the three criteria, licensees should retain in their Technical Specifications Limiting Conditions for Operations, Action Statements and
'Surveillance Requirements for four systems.
One of these four explicitly identified is the reactor core isolation cooling system.
The Commission's position is based on their ob'servation that operating experience and
. probabi listic.risk assessment have generally shown the systems to be" important to public health and safety.
3.0 CONCLUSION
Based on the recognition that operating experience and probabi listic risk assessment have shown the reactor core isolation cooling system to be important to public health and safety, the request for the amendment is denied.
Principal Contributor:
R. Samworth Dated:
foray 2, 1989
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