ML13331A441
| ML13331A441 | |
| Person / Time | |
|---|---|
| Site: | San Onofre  |
| Issue date: | 06/18/1990 |
| From: | Nandy F SOUTHERN CALIFORNIA EDISON CO. |
| To: | NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM) |
| Shared Package | |
| ML13331A442 | List: |
| References | |
| NUDOCS 9006200154 | |
| Download: ML13331A441 (4) | |
Text
Southem California Edison Company 23 PARKER STREET IRVINE, CALIFORNIA 92718 F. R. NANDY TELEPHONE MANAGER OF NUCLEAR LICENSING June 18, 1990 (714) 587-5400 U. S. Nuclear Regulatory Commission Attention: Document Control Desk Washington, D. C. 20555 Gentlemen:
Subject:
Docket No. 50-206 Amendment Application No. 180 Supplement, 480 Volt System Reconfiguration and Equipment Operability During Cycle 11 Refueling Outage San Onofre Nuclear Generating Station, Unit 1 By letter dated April 19, 1990, Southern California Edison (SCE) submitted Amendment Application No. 180, which proposed changes to the San Onofre Unit 1 Technical Specifications to reflect the 480 volt system modifications planned for the Cycle 11 refueling outage. The system configuration changes are described by the before and after drawings enclosed as Figures 1 and 2. A full core off-load will also be conducted during this outage in order to perform work on the thermal shield and the 10-year reactor vessel in-service inspection. Administrative controls will be imposed and temporary modifications will be implemented as described below to ensure that identified systems and equipment remain capable of performing their required functions during the full core off-load and 480 volt system modifications. This letter also provides an editorial revision to two pages submitted in Amendment Application No. 180 and clarifies the need for fire protection of new Station Service Transformer 3.
DESCRIPTION OF ADMINISTRATIVE CONTROLS Since the core will be fully off-loaded during the outage, few technical specifications will continue to apply. The SONGS 1 Technical Specifications define mode 6 as the condition in which the average coolant temperature is less than or equal to 140*F with "the reactor vessel head unbolted or removed and fuel in the vessel."
Some specifications do not specify applicable modes but describe the specific conditions in which they are applicable. For example, Section 3.2, "Chemical and Volume Control System," states that it applies "when fuel is in the reactor."
However, several plant systems will F'
FDC
Document Control Desk June 18, 1990 nonetheless need to be in-service during the core off-load. Administrative controls will ensure identified systems and components remain capable of performing required functions where technical specifications do not specify applicability.
- 1.
Auxiliary Electrical Supply Specification 3.7.111 will be extended by administrative controls to apply while the reactor vessel is defueled. One operable off site power source and one operable diesel generator will provide one train of diverse and redundant electrical power.
- 2.
Spent Fuel Pool Cooling System Specification 3.8.B, which specifies the spent fuel pool (SFP) water level and heavy loads restrictions, will remain in effect. In addition, administrative controls will require one safety-related (SR) SFP cooling train to be operable and in operation, and one non safety related (NSR) train to be operable and in standby mode.' The SR SFP cooling train will consist of the primary spent fuel pool cooling pump, the common SFP heat exchanger, one component cooling water (CCW) pump, one CCW heat exchanger, one saltwater cooling pump, associated flow paths, and valves. The standby NSR SFP cooling train will consist of the spare SFP cooling pump, an additional CCW pump, the auxiliary saltwater cooling pump, and associated heat exchangers, flow paths and valves. The standby cooling train components will be provided with NSR power from the construction load center prior to the initiating core off-load.
In order to maintain the primary SFPC pump operable during modification of its normal power supply (Motor Control Center 2
[MCC-2] from 480V bus 2), a temporary facility modification will realign MCC-2 to 480V bus 1 (See Figure 3 for sequence of events).
This power switchover will be completed prior to the core off-load while the heat load in the spent fuel pool is very low. Recent outages of the SFPC System demonstrate that the pool temperature will not increase significantly. Upon completion of the 480V bus 2 outage, we will reconnect MCC-2 to 480V Bus 2.
A second temporary outage of the primary SFPC pump will occur approximately 50 days into the Cycle 11 outage. At this time the full core off-load will be in the SFP. During this brief pump outage, the spare pump, and its associated standby SFP cooling train
'The NSR train will consist of the spare SFP cooling pump installed as described in Amendment Application No. 182, submitted on May 16, 1990.
Document Control Desk June 18, 1990 will be placed in-service. We will conservatively limit the primary pump outage to 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br />. As stated in Amendment Application No. 182, this will ensure the pool temperature remains below 150F at all times during the Cycle 11 outage.
- 3.
Control Room Emergency Air Treatment System Although no requirement presently exists in the SONGS 1 Technical Specifications, we have implemented an administrative control for the control room emergency air treatment system (CREATS) to be operable in MODES 5 and 6. The administrative control will provide an action statement to suspend core alteration and positive reactivity insertion should the system become inoperable. This administrative control will apply during the full core off-load.
Temporary SR power will be supplied to the CREATS during part of the outage. The CREATS is a single train system on MCC-1, normally fed by 480V Bus 1. The temporary facility modification will align MCC-1 to newly designated Train B 480V Bus 4 prior to 480V Bus 1 being taken out of service (See Figure 3 for sequence of events).
Upon completion of the 480V Bus 1 outage, we will reconnect MCC-1 to 480V Bus 1.
- 4.
Spent Fuel Pool Makeup The refueling water filter pump provides one source of makeup water to the spent fuel pool from the refueling water storage tank. This pump will be required to be operable during the outage except for an outage of less than 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> to allow for power switchover discussed above.
Makeup to the spent fuel pool is provided in the event of a loss of cooling resulting in eventual pool boiling. The maximum boil-off rate in the SFP based on recent calculations is bounded by the 40 gpm stated in UFSAR Section 9.1.
The refueling water filter pump is normally powered from MCC-2 on 480V Bus 2. Similar to the primary SFP cooling pump, the refueling water filter pump will be powered from a safety-related power source for the duration of the outage (See Figure 3 for sequence of events). Additional makeup capability will be available from the primary makeup tank, the fire water system, and the condensate storage tank as described in UFSAR Section 9.1.
ADDITIONAL INFORMATION CONCERNING STATION SERVICE TRANSFORMER 3 In a discussion concerning Amendment Application 180, the NRC staff questioned whether a technical specification is required for fire protection of new Station Service Transformer (SST) 3. New SST 3 is
- /1e Document Control Desk June 18, 1990 manufactured by Asea Brown Boveri and rated at 1,500 kVA. The transformer is an outdoor, ventilated, and dry type design, which does not require a fire protection system. Therefore, an associated fire protection technical specification change is not required.
EDITORIAL CHANGES IN AMENDMENT APPLICATION NO. 180 Amendment Application No. 180 included an operability requirement for new manual transfer switch, MTS-8. The amendment application indicated that the normal power supply for MTS-8 was 8-1491. However, after submittal of the amendment application, the breaker number for the normal power source of MTS-8 was reassigned as 8-1480B. Enclosed is a revision of Page 4.4-4 of the proposed technical specifications and a revision of Figure 3 of to Amendment Application No. 180 which reflect this change.
If you have any questions or comments, please contact me.
Sincerely, Enclosure cc: J. B. Martin, Regional Administrator, NRC Region V C. Caldwell, NRC Senior Resident Inspector, San Onofre Units 1, 2 and 3 J. H. Hickman, California Department of Health Services