ML20128A420

Safety Evaluation Supporting Amend 91 to License DPR-46

ML20128A420
Person / Time
Site:	Cooper
Issue date:	05/13/1985
From:	Office of Nuclear Reactor Regulation
To:
Shared Package
ML20128A409	List: ML20128A406 ML20128A420
References
TAC-55005, NUDOCS 8505240217
Download: ML20128A420 (3)

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UNITED STATES w

. g, NUCLEAR REGULATORY COMMISSION O

j WASHINGTON, D. C. 20555

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SAFETY EVALUATION BY THE OFFICE OF NUCLEAR REACTOR REGULATION SUPPORTING AMENDMENT NO. 91 TO FACILITY OPERATING LICENSE NO. DPR-46 NEBRASKA PUBLIC POWER DISTRICT COOPER ~ NUCLEAR STATION DOCKET NO. 50-298 f

1.0 INTRODUCTION

This amendment modifies the Cooper Nuclear Station Technical Specifications to (1) reflect modifications perfonned as a result of the Mark I Containment Long-Term Program, and (2) remove the requirement for continuous monitoring i

of the containment for gross leakage of nitrogen. These Technical Specification changes were proposed by the Nebraska Public Power District, the licensee for Cooper Nuclear Station, in a letter dated May 7,1984.

2.0 EVALUATION 2.1 Mark I Containment Long-Term Program 1

As a result of modifications performed relative to the Mark I Containment Long-Term Program, the licensee proposes to delete the Technical Specification requirements to establish and maintain a drywell to suppression chamber differential pressure during all reactor operating modes.

In conjunction with this change, the licensee also proposes to delete from the Technical Specifications the limiting conditions for operation and surveillance requirements for the drywell-suppression chamber differential pressure instrumentation. To support these proposed changes, the licensee states that the containment structural evaluation, that was performed and reported in the Plant Unique Analysis Report (PUAR), used as initial conditions differential pressures of both 1.0 psid and 0.0 psid.

The analysis determined that although the zero differential pressure resulted in higher loads in some cases, the minimum structural design margins were still met. The staff agrees that the proposed Technical Specification changes are consistent with the PUAR analysis and that.

maintaining a drywell-suppression chamber differential pressure. is not required. The PUAR was approved by the staff in a letter from D. B. Vassallo to J. M. Pilant dated January 20, 1984.

The licensee also proposes to change the maximum suppression pool water 3 volume in Section 3.7.A.1 of the Technical Spgcifications from 91,000 ft to 3

91,100 ft. The proposed volume of 91,100 ft is consistent with the volume used in the Mark I evaluations as reported in the PUAR. These evaluations were previously approved by ghe staff in the January 20, 1984 letter cited above. The use of 91,100 ft as the maximum suppression pool volume is, therefore, acceptable.

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Based on our review we have determined that the proposed Technical Specifications discussed above are consistent with previously-approved modifications involved in-the Mark I Containment Long-Term Program and are, therefore.. acceptable.

2.2 Containment Monitoring for Nitrogen Leakage The licensee proposes to delete item 4.7.A.2.g from the Technical Specifications to remove the requirement to continuously monitor the containment for gross leakage of nitrogen.. The licensee correctly notes that the specification, as written, is ambiguous with no quantitative criteria given to define gross leakage or time allowed for the monitoring system to be out of service.

Ue have reviewed the licensee's application and have determined that continuous monitoring of the containment is not required because other Cooper Nuclear Station Technical Specifications are.provided to:

a) i

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monitor and maintain the oxygen concentration at less than 4% by volume 4

during operating modes 1, 2 and 3;

-b) conduct a drywell-to-suppression chamber bypass leak test; and c) conduct a containment leak rate test.

i-The leak rate tests specified in items b) and c) above are performed in i

accordance with the acceptance criteria of Standard Review Plan Section 16.0 1

in that they are consistent with NUREG-0123, Revision 3, Standard Technical Specifications.-

I; Based on our review, we conclude that continuous monitoring of the L

c.ontainment for gross leakage of nitrogen as required by item 4.7.A.2.g of the Technical Specifications is not required and the proposed Technical i-Specification change is, therefore, acceptable.

3.0 ENVIRONMENTAL CONSIDERATION

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.This amendment involves a change in the installation or use of a facility component located within the restricted area as defined in 10 CFR Part 20 and L

a change in a surveillance requirement. The staff has determined that the amendment involves no significant increase in the amounts, and no significant f

change in the types, of any effluents that may be released offsite, and that l

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 51.22(c)(9). Pursuant to 10 CFR 51.22(b) no environmental impact statement

3-or' environmental assessment need be prepared in connection with the issuance of this amendinent.

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4.0 CONCLUSION

We have 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, and (2) such activities will.be conducted in compliance with the Commission's regulations and the issuance of the amendment will not be inimical to the common defense and security or to the health and safety of the public.

Principal Contributor:

F. Eltawila Dated:

May 13,1985 4

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