ML14175A803
| ML14175A803 | |
| Person / Time | |
|---|---|
| Site: | Robinson  |
| Issue date: | 04/04/1984 |
| From: | Office of Nuclear Reactor Regulation |
| To: | |
| Shared Package | |
| ML14175A802 | List: |
| References | |
| NUDOCS 8404240505 | |
| Download: ML14175A803 (3) | |
Text
SAFETY EVALUATION BY THE OFFICE OF NUCLEAR REACTOR REGULATION RELATED TO AMENDMENT NO. 79 TO FACILITY OPERATING LICENSE NO. DPR-23 CAROLINA POWER AND LIGHT COMPANY H. B. ROBINSON STEAM ELECTRIC PLANT, UNIT NO. 2 DOCKET NO. 50-261 Introduction By Letter dated January 11, 1983, the Licensee proposed certain changes to the TechnicaL Specifications for H. B. Robinson, Unit 2, concerning the allowable containment internal pressure.
The Licen see has proposed these changes to make the TechnicaL Specifications consistent with the current safety analysis for the pLant.
Technical Specification (TS) 3.6.2 currently requires that action be taken to reduce the containment internal pressure if it exceeds 2 psig, or to shut down the plant within eight hours.
The 2 psig Limit is based on a previous safety analysis which calculated a peak accident pressure inside containment of 37.8 psig.
Since the containment design pressure is 42 psig, the pre-accident containment pressure could have been as high as 4 psig; when this initial value is added to the peak accident pressure (37.8 psig), the containment pressure would not exceed its design value.
The TS Limit of 2 psig was originaLLy chosen to provide additional safety margin.
The Licensee has since discovered an error in the calculation of the containment net free volume stated in the facility FSAR.
This volume was recalculated and found to be Less than originaLLy stated.
As a result, caLcuLated peak accident pressure is now 40 psig; the previous value was 37.8 psig.
Since the containment design pressure is 42 psig, 8404240505 840404 PDR ADOCK 05000261 P
-2 the containment. internal pressure at the onset of a LOCA must be no more thon 2 psig to prevent exceeding the containment design pressure.
The Licensee has proposed that TS 3.6.2 be revised to reduce the containment internal pressure Limit from 2 psig to 1 psig, to provide a 1 psig safety margin.
The associated basis in the TS would atso be revised to indicate that the TS 3.6.2 Limit of 1 psig is based on using 50% of the calculated difference of 2 psig between the peak accident pressure and the design pressure.
The staff finds the proposed changes to the facility Technical Specifications to be consistent with the Licensee's revised safety anaLysis and, therefore, acceptable.
Environmental Consideration We have determined that the amendment does not authorize a chanae in effluent types or total amounts nor an increase in power level and will not result in any significant environmental impact. Having made this determination, we have further concluded that the amendment involves an action which is insignificant from the standpoint of environmental impact and, pursuant to 10 CFR §51.5(d)(4),
that an environmental impact statement or negative declaration and environmental impact appraisal need not be prepared in connection with the issuance of this amendment.
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 he
-3 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 this amendment will not be inimical to the common defense and security or to the health and safety of the public.
Dated: April 4, 1984 Principal Contributor:
J. Pulsipher