ML17056A788
| ML17056A788 | |
| Person / Time | |
|---|---|
| Site: | Nine Mile Point  |
| Issue date: | 04/25/1990 |
| From: | Office of Nuclear Reactor Regulation |
| To: | |
| Shared Package | |
| ML17056A787 | List: |
| References | |
| NUDOCS 9004300021 | |
| Download: ML17056A788 (4) | |
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UNITED STATES NUCLEAR REGULATORY COMMISSION WASHINGTON, O. C. 20555 SAFETY EVALUATION BY THE OFFICE OF NUCLEAR REACTOR REGULATION RELATED TO AMENDMENT NO.
115 TO FACILITY OPERATING LICENSE NO.
DPR-63 NIAGARA MOHAWK POWER CORPORATION NINE MILE POINT NUCLEAR STATION UNIT NO.
1 DOCKET NO. 50-220 INTRODUCTION By letter dated December 8, 1989, Niagara Mohawk Power Corporation (the licensee) submitted an application to amend the Nine Mile Point Unit No.
1 Technical Specifications Appendix A, Section 3.3.1, Oxygen Concentration and the associated Bases.
By this amendment, the oxygen concentration in the primary containment atmosphere would be expressed in percent by volume rather than percent by weight.
The proposed amendment would also delete in section 3.3.1a.
a reference to the startup test program which no longer applies.
DISCUSSION Technical Specifications Appendix A, Section 3.3.1 and associated Bases provide the requirements for oxygen concentration within the primary containment system.
Oxygen concentration limits assure that in the event of a loss of coolant accident any hydrogen generation will not result in a combustible mixture within the primary containment system.
As stated in Nine Mile Point 1 Updated Final Safety Analysis Report (UFSAR),Section VII G.1.0, Combustible Gas Control System:
The combustible gas control system is designed to prevent a combustible hydrogen-oxygen concentration from accumulating in the primary containment atmosphere immediately following or during a loss-of-coolant accident.
The system is capable of reducing and maintaining the oxygen content of the primary containment atmosphere below 4.0 percent by volume to preclude the possibility of hydrogen combustion regardless of the amount of hydrogen available.
In Section 3.3.1a and associated Bases of Nine Mile Point Unit 1 current Technical Specification the oxygen concentration is expressed in percent.
This terminology differs from the UFSAR chapter quoted above in that it fails to specify the units of quantity.
In Section 3.3.1b.
the oxygen concentration is expressed in percent by weight.
This terminology represents an error.
It is clear from the UFSAR chapter above that the requirement is to maintin the primary containment oxygen concentration below four percent by volume during power operation.
The Standard Technical Specifications applicable to NMP-1 desiqn support this assertion.
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Tbe proposed amendment would also remove in Section 3.3.1a.
a reference to the startup test program.
This reference is not applicable to the current or future operation condition since it applies to the initial startup test program already completed.
Therefore, the deletion of "After completion of the startup test program and demonstration of plant electrical output" in Section 3.3.1a is warranted.
On the basis that the proposed amendment does not affect safe operation at Nine Mile Point Unit 1 and maintains the plant within the design basis, the staff finds the proposed amendment acceptable.
ENVI RONMENTAL CONSIDERATION This amendment involves a change in the installation or use of the facility components located within the restricted areas as defined in 10 CFR 20.
The staff has determined that this amendment involves no significiant 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 Commission has previously issued a proposed finding that this amendment involves no significant hazards consideration and there has been no public comment on such finding.
Accordingly, this amendment meets the eligibility criteria for categorical exclusion set forth in 10 CFR Sec 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 this amendment.
CONCLUSION We have concluded, based on the consideration 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, and (2) such activities will be conducted in compliance with the Commission's regulations and the issuance of these amendments will not be inimical to the common defense and security or to the helath and safety of the public.
Dated:
April 25, 1990 PRINCIPAL CONTRIBUTOR:
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