ML13310B541
| ML13310B541 | |
| Person / Time | |
|---|---|
| Site: | San Onofre  |
| Issue date: | 07/06/1984 |
| From: | Office of Nuclear Reactor Regulation |
| To: | |
| Shared Package | |
| ML13310B539 | List: |
| References | |
| TAC-42131 NUDOCS 8407090235 | |
| Download: ML13310B541 (5) | |
Text
REG UNITED STATES 0
NUCLEAR REGULATORY COMMISSION WASHINGTON, D. C. 20555 SAFETY EVALUATION BY THE OFFICE OF NUCLEAR REACTOR REGULATION SUPPORTING AMENDMENT NO. 77 TO PROVISIONAL OPERATING LICENSE NO. DPR-13 SOUTHERN CALIFORNIA EDISON COMPANY SAN ONOFRE NUCLEAR GENERATING STATION, UNIT NO. 1 DOCKET NO. 50-206
1.0 INTRODUCTION
By letter dated December 5, 1983, Southern California Edison Company (the licensee) proposed changes to the Technical Specifications for San Onofre Nuclear Generating Station, Unit No. 1. The proposed changes provide for functional redundancy in the decay heat removal methods during all methods of plant operation. This amendment application was submitted in response to I&E Bulletin 80-12 and the model Technical Specifications provided by NRC letter dated June 11, 1980. The proposed changes supersede
-Section 3.1.2, Section 3.8 and Table 4.1.2 of Proposed Change No. 96 which was submitted by letter dated December 1, 1980.
A Notice of Consideration of Issuance of Amendment and Proposed No Significant Hazards Consideration Determination and Opportunity for Hearing related to the requested action was published in the Federal Register on March 22, 1984 (49 FR 10746). A request for hearing and public comments were not received.
2.0 DISCUSSION AND EVALUATION The proposed Technical Specifications (TSs) were evaluated against the model Technical Specifications (June 1980) or against the Westinghouse Standard Technical Specifications (NUREG-0452), Revision 4 (November 1981), for those areas where the Standard Technical Specifications have changed since issuance of the model specifications.
2.1 Section 1.0 - Definitions A new definition has been added to section 1.0 to define "residual heat removal (RHR) train" as the set of components including one RHR pump aligned with one RHR heat exchanger, one component cooling water pump aligned with the same RHR heat exchanger and with one component cooling water heat exchanger, and one salt water cooling water pump aligned with the same component cooling water heat exchanger.
-2 This definition addresses the heat removal paths from the reactor to the ultimate heat sink. The term "RHR train" is used in the proposed technical specification changes below.
It should be noted, for the discussion which follows, that section 1.0 of the San Onofre 1 Technical Specifications already contains the definitions of "OPERABLE" as well as of the operational modes.
2.2 Specification 3.1.2 Operational Components Existing Technical Specifications 3.1.2.B through 3.1.2.F have been deleted. A new section 3.1.2.B has been added which contains the specification on operability of both pressurizer safety valves that was formerly specification 3.1.2.C(1).
The remaining aspects of existing specifications 3.1.2.B through F have been expanded as discussed below to describe requirements for operability of equip ment such as reactor coolant pumps and steam generators during Modes 1 through 4.
The basis for section 3.1.2 has also been revised to discuss the reasons for the functional redundancy requirements in each mode.
A. Modes 1 and 2 (Power Operation and Startup).
Proposed TSs 3.1.2.C and 3.1.2.D state that while in these modes, all three reactor coolant loops and associated steam generators and reactor coolant.
pumps shall be in operation. With less than the required loops in operation, the unit must be in at least HOT STANDBY within 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br />, with exceptions for physics testing and limited time periods at low power. The operation and circulating of reactor coolant of the specified loops shall be verified every 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br />, per Table 4.1.2 of the Technical Specifications.
These TSs are-consistent with the model Technical Specifications provided in the NRC letter of June 11, 1980 and are, therefore, acceptable.
B. Mode 3 (Hot Standby)
Proposed TS 3.1.2.E provides that during this mode at least two reactor coolant loops shall be operable and at least.one loop shall be.in operation.
Action statements are specified for when less than the required number of loops are operable. The surveillance requirements are provided in Table 4.1.2. These proposed specifications are consistent with the model Technical Specifications and are, therefore, acceptable.
C. Mode 4 (Hot Shutdown)
In this mode, proposed TS 3.1.2.F would-require that two of the reactor coolant loops or residual heat removal trains be operable, and that at least one train/loop shall be in operation. Certain exceptions are
-3 allowed for limited time periods when additional conditions are met, such as margin to saturation for the core outlet temperature. Action statements and surveillance requirements are also specified.
The specifications for this mode are consistent with the corresponding
_sections of the Westinghouse Standard Technical Specifications, with one exception: the specified margin to saturation for San Onofre 1 is 400 F.
This provides more margin than the 100Frequired by the Westinghouse.
Standard Technical Specifications.
Therefore, these specifications are acceptable.
D. Mode 5 (Cold Shutdown).- Reactor Coolant Loops Filled.
Specification 3.1.2.G applies to this condition. At least one RHR train shall be operable and in operation and either one additional RHR train shall be operable or the secondary side of at least two steam generators shall be filled. The surveillance requirements are given in Table 4.1.2. These requirements are consistent with the corresponding Westinghouse STS requirements and are, therefore, acceptable.
E. Mode 5 (Cold Shutdown) - Reactor Coolant Loops§Not Filled.
For this mode, proposed specification 3.1.2.H specifies that two RHR trains shall be operable with one RHR train in operation. These requirements, the action statements and the surveillance statements (in Table 4.1.2) are in conformance with the Westinghouse Standard Technical Specifications and are, therefore, acceptable.
2.3 Specification 3.8 Fuel Loading and Refueling Existing TS 3.8.A.3 is deleted and replaced by new sections 3.8.A.3 and 3.8.A.4 (discussed below). In addition, TSs 3.8.A.4 through 3.8.A.7 were renumbered to 3.8.A.5 through 3.8.A.8 to accommodate insertion of the above specifications. Reference to section A.4 in two places was changed to section A.5 to correspond. The basis for section 3.8 has also been revised to reflect the above changes.
A. Mode 6 (Refueling) - Level in Refueling Pool above 40' 3".
Proposed TS 3.8.A.3 requires one heat removal path to be in operation and circulating reactor coolant at a minimum flow rate of greater than or equal to 400 gallons per minute (gpm).
The basis for selection of a flow rate of 400 gpm was provided in a letter dated May 17, 1984 from M. Medford to D. Crutchfield. This flow rate provides turbulent mixing to prevent boron stratification and to minimize the reactivity addition effects of any boron dilution event. A plant-specific number was selected rather than the number given in the model specification which is applicable for larger plants. The flow rate required for decay heat removal will vary during the refueling
-4 operation depending on core conditions.
Reactor coolant system temperature is monitored and recorded to ensure that the water in the reactor vessel remains below 140 0F. The action statements and surveillance frequencies are consistent with the Westinghouse Standard Technical Specifications. Therefore, these proposed changes are acceptable.
B. Mode 6 (Refueling) - Level in Refueling Pool Below 40' 3" Proposed TS 3.8.A.4 requires that one heat removal path be in operation and that an additional path be operable. The allowable paths.are the two RHR trains and a path consisting of a refueling water pump taking suction on the refueling pool through the recirculation heat exchanger and back to one of the reactor cold legs.
This differs from the Westinghouse Standard Technical Specifications in that the recirculation flow path is given as an alternative to an RHR train. In the refueling mode, this flow path also provides forced circulation flow at a flow rate sufficient to provide decay heat removal and adds functional redundancy since it relies for the most part on components not part of the RHR train.
The action statements and surveillance requirements are consistent with the Westinghouse Standard Technical Specifications.
Therefore, the proposed specifications are acceptable.
2.4 Table 4.1.2 Minimum Equipment Check and Sampling Frequency A new item has been added to Table 4.1.2 which contains the surveillance requirements for TS 3.1.2.C through H and 3.8.A.3 and 3.8.A.4. As discussed under the corresponding sections above, these required checks and their frequencies are consistent with the model TS provided by the NRC or the Westinghouse Standard Technical Specifications and are, therefore, acceptable.
3.0 ENVIRONMENTAL CONSIDERATION
This amendment involves a change in the installation or use of a facility component located within the restricted area as defined by 10 CFR 20. The staff has determined that the amendment involves no significant 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 occupation 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 or environmental assessment need be prepared in connection with the issuance of this amendment.
-5
4.0 CONCLUSION
The Staff has 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 this amendment will not be inimical to the common defense and security or to the health-and safety of the public.
5.0 ACKNOWLEDGEMENT E. McKenna prepared this evaluation.
Dated: July 6, 1984