ML13326A770
| ML13326A770 | |
| Person / Time | |
|---|---|
| Site: | San Onofre  |
| Issue date: | 05/13/1991 |
| From: | Morgan H SOUTHERN CALIFORNIA EDISON CO. |
| To: | NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM) |
| Shared Package | |
| ML13326A771 | List: |
| References | |
| GL-90-06, GL-90-6, NUDOCS 9105170308 | |
| Download: ML13326A770 (2) | |
Text
Southern California Edison Company P. 0.
BOX 128 SAN CLEMENTE, CALIFORNIA 92672 H. E. MORGAN TELEPHONE VICE PRESIDENT AND SITE MANAGER May 3
1991 714-368-9470 SAN ONOFRE U. S. Nuclear Regulatory Commission Attention:
Document Control Desk Washington, D. C. 20555 Gentlemen:
Subject:
Docket No. 50-206 Amendment Application No. 194 Overpressure Mitigation System SEP Topic V-11.B, "Residual Heat Removal System Interlock Requirements" Generic Letter 90-06 San Onofre Nuclear Generating Station, Unit 1
References:
A)
Letter, F. R Nandy, SCE to NRC, dated February 1, 1991.
B)
Generic Letter 90-06, "Resolution of Generic Issue 70,
'Power-Operated Relief Valve and Block Valve Reliability,' and Generic Issue 94, 'Additional Low Temperature Overpressure Protection for Light-Water Reactors,' Pursuant to 10 CFR 50.54(f)"
C)
NUREG-0829, "Integrated Plant Safety Assessment Systematic Evaluation Program," December 1986 The enclosure to this letter provides Amendment Application No. 194, which is requested to revise Specifications 3.1.2, "Operational Components," 3.1.3, "Combined Heatup, Cooldown and Pressure Limitations," 3.1.5, "Pressurizer Relief Valves," 3.2,"Chemical and Volume Control System," 3.20, "Overpressure Protection Systems," 4.1.6,"Pressurizer Relief Valves," and 4.20, "Overpressure Protection Systems," of the Appendix A Technical Specifications for San Onofre Nuclear generating Station, Unit 1.
The proposed change is being submitted to close SEP Topic V-11.B, "Residual Heat Removal System Interlock Requirements," and to incorporate a change in the design basis for the Overpressure Mitigation System (OMS).
The proposed change will revise the heatup/cooldown curves in accordance with current regulatory guidance, change the requirements for operation of the OMS, and incorporate the appropriate recommendations of Generic Letter (GL) 90-06.
Other information requested concerning quality assurance requirements, maintenence and replacement parts addressed in GL 90-06 will be provided in a separate letter. The proposed Technical Specifications are intended to replace the current administrative controls (Reference A) for operation of the OMS.
9105170)308 9 10513 PDR ADOCK 05000206 P
I*
Document Control Desk May 13, 1991 SEP Topic V-11.B consists of two subtopics, "Residual Heat Removal System Interlocks," and "Overpressure Protection of the Residual Heat Removal System."
The former subtopic addressing the interlocks was closed by NUREG 0829. The latter subtopic has an open item to submit new Technical Specifications to require operation of the OMS whenever the Residual Heat Removal (RHR) system is in operation. We request your approval of the enclosed submittal to close SEP Topic V-11.B.
We have completed a new analysis for overpressure protection of both the Reactor Coolant System (RCS) and RHR system. As discussed in the amendment application, our analysis has determined that the operation of the RHR relief valve, RV-206, is sufficient to protect both the RCS and RHR.system from low temperature overpressure transients without the operation of the.pressurizer Power Operated Relief Valves (PORVs). The amendment application proposes removing the requirement for operation of the PORVs for OMS and incorporates new requirements for operation of RV-206. The proposed specifications contain restrictions on charging pump flow, and path alignment to address OMS single failure concerns.
If you have any questions or require additional information, please contact me.
Very truly yours, cc:
George Kalman, NRC Project Manager, San Onofre Unit 1 J. B. Martin, Regional Administrator, NRC Region V C. Caldwell, NRC Senior Resident Inspector, San Onofre Units 1, 2 and 3 C. D. Townsend, NRC Resident Inspector, San Onofre Unit 1 J. H. Hickman, California Department of Health Services