ML19331E137
| ML19331E137 | |
| Person / Time | |
|---|---|
| Site: | Oconee  |
| Issue date: | 10/23/1974 |
| From: | US ATOMIC ENERGY COMMISSION (AEC) |
| To: | |
| Shared Package | |
| ML19331E131 | List: |
| References | |
| NUDOCS 8009050551 | |
| Download: ML19331E137 (3) | |
Text
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O) e UNITED STATES ATOMIC ENERGY COMMISSION U
l WASHINGTON, D.C. 20545 p
SAFETY EVALUATION BY THE DIRECTORATE OF LICENSING SUPPORTING AMENDMENT NO. 5 TO FACILITY LICENSE NO. DPR-38 CHANGE No. 15 TO TECHNICAL SPECIFICATIONS; AMENDMENT No. 5 TO FACILITY LICENSE NO. DPR-47 CHANGE No. 10 TO TECHNICAL SPECIFICATIONS; AMENDMENT NO. 2 TO FACILITY LICENSE NO. DPR-55 CHANGE NO. 2 'r0 TECHNICAL SPECIFICATIONS; DUKE POWER COMPANY OCONEE NUCLEAR STATION, UNITS 1, 2, AND 3 DOCKET NOS. 50-269, 50-270, AND 50-287 Introduction By letter dated September 4,1974, Duke Power Co' pany requested changes m
to the Technical Specifications appended to Facility Operating Licenses No. DPR-38, DPR-47, and DPR-55 for the Oconee Nuclear Station. The proposed changes involve the action to be taken should a containment personnel hatch, emergency hatch, or isolation valve become inoperative or require maintenance when the plant is in an operating condition.
Discussion Air locks are provided to allow personnel to ent.er the containment when the plant is operational without violating containment integrity. Both the inner and outer doors on these air locks meet the design specifications for structural integrity and leak rate. This design feature allows one door to be open without violating containment integrity.
Containment integrity presently requires that al1~ isolation valves be operable, locked closed, or secured by a blind flange.' Should an isolation valve be found to be inoperable, prompt action is necessary either to repair the valve, secure the valve, or shut down the reactor.
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The current Technical Specifications do not permit continued operation should a containment personnel hatch, emergency hatch, or isolation valve become inoperative when the plant is in an operating condition.
However, the allowable times for remedial action are not specified.
This proposed change would prescribe the time allowable for remedial action and specify the action that must be taken should the equipment be inoperable at the end of this period.
Evaluation In reviewing this request, the staff determined that it was not the original intent of the Technical Specifications to preclude timely remedial action to restore inoperable containment doors and isolation valves to an operable condition.
The proposed Technical Specification change would add a new Section 3.6.4 as folk ws:
3.6.4 Exceptions to 3.6.1, 3.6.2, and 3.6.3 shall be as follows:
a.
If either the personnel or emergency hatches become inoperable, except as a result of an inoperable door gasket, the hatdt shall be restored to an operable status within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />, or the reactor shall be in cold shutdown within the next 36 hours4.166667e-4 days <br />0.01 hours <br />5.952381e-5 weeks <br />1.3698e-5 months <br />.
If a hatch is inoperaole due to an inoperable door gasket:
1.
The remaining door of the affected hatch shall be l
closed and sealed.
2.
The hatch shall be restored to operable status within seven days or the reactor shall be in cold shutdown within the next 36 hours4.166667e-4 days <br />0.01 hours <br />5.952381e-5 weeks <br />1.3698e-5 months <br />.
b.
A containment isolation valve may be inoperable provided either:
1.
The inoperable valve is restored to operable status within four hours.
j 2.
The affected penetration is isolated within four hours by the use of a deactivated automatic va1Lve secured and locked in the isolated position.
1 3.
The affected penetration is isolated within four hours by the use of a closed manual valve or blind flange.
4.
The reactor la in the hot shutdown coadition within 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> and cold shutdown within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />.
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These limitations are. consistent with the current staff position as represented by technical specifications being issued with new operating licenses.
This proposed change was also reviewed to determine the effect on con-tainment integrity. In the case of a defective air lock door or gasket, Section 5.1.4.4 of the Oconee Final Safety Analysis Report states that the personnel air lock doors are designed to withstand all reactor building design conditions with either one or both doors closed. These doors are equipped with interlocks which prevent both doors being open at the same time. Thus, continued operation with a defective door for the very short periods of time allowed for repair does not represent a significant degra-dation of safety margin.
The containment isolation system is addressed in the Oconee Final Safety Analysis Report. Section 5.2.1 states that no single failure of an active component could result in a loss of isolation or intolerable leakage.
Thus, with this available redundancy, continued operation of the reactor with an inoperable isolation valve for the very short period of time allowed for repair (four hours) does not represent a significant degradation of safety margin.
Based on this review, the staff concluded that the containment integrity assumed in the design basis loss of coolant accident analysis will not be jeopardized by this change and that the probability or consequence of an accident will not be significantly affected.
Conclusion i
We have concluded, based on the reasons discussed above, that the authori-zation of these changes does not involve a significant hazards consideration.
We also conclude that there is reasonable assurance (i) that the activities authorized by these amendments can be conducted without endangering the health and safety of the public, and (ii) that such activities will be conducted la compliance with the CommisMon's regulations and the issuance of these amendments will not be inimical to the common defense and security or to the health and safety of the public..
..a Date: October 23, 1974
UNITED STATES ATOMIC ENERGY COMMISSION DOCIET HOS. 50-269, 50-270. AND 50-287 DUKE POWER COMPANY NOTICE OF ISSUANCE OF AMENIMENTS TO FACILITY OPERATING LICENSES Notice is hereby given that the U.S. Atomic Energy Commission (the Coinnission) has issued Amendments No. 5, 5, and 2 to Facility Operating Licenses No. DPR-38, DPR-47, and DPR-55, respectively,. issued to Duke Power Company which revised Technical Specifications for operation of the Oconee Nuclear Station, Units 1, 2, and 3, located in 'Sconee County, South Carolina. The==ndman.ts are effective as of the date of issuance.
These amendments prescribe the action required should a containment personnel hatch, emergency hatch, or isolation valve become inoperative or require maintenance when the plant is in an operating condition.
The application for the amendments complies with the standards and requirements of the Atomic Energy Act of 1954, as amended (the Act), and the Commission's rules and regulations. The Commission has made appro-priate findings as required by the Act and the Commission's rules and regulations in 10 CFR Chapter I, which are set forth in the license i
amendments.
For further details with respect to this action, see (1) the appli-cation for amendments dated September 4, 1974, (2) Amenden ts No. 5, 5,
and 2 to Licenses No. DPR-38, DPR-47, and DPR-55, with any attachments, and (3) the Comunission's related Safety Evaluation. All of these items l
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r 2-are available for public inspection at the Commission's Public Document Room,1717 H Street, NW., "Jeahington, D.C. and at the Oconee County Library, 201 South Spring Street, Wm1h=11a, South Carolina 29691.
A copy of items (2) and (3) may be obtained upon request addressed to the U.S. Atomic Ensegy Commission, Washington, D.C.
20545, Attention:
Deputy Director for Reactor Projects, Directorate of Licensing - Regulation.
Dated at Bethesda, Maryland, this 23rd day of October 1974.
FOR THE ATOMIC ENERGY COMMISSION
> y4' Robert A. Purple, Chief Operating Reactors Branch #1 Directorate of Licensing l
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