ML13316B749
| ML13316B749 | |
| Person / Time | |
|---|---|
| Site: | San Onofre  |
| Issue date: | 06/09/1980 |
| From: | Baskin K Southern California Edison Co |
| To: | Engelken R NRC/IE, NRC/RGN-V |
| References | |
| IEB-80-06, IEB-80-6, NUDOCS 8008060061 | |
| Download: ML13316B749 (6) | |
Text
Southern California Edison Company P. 0. BOX 800 2244 WALNUT GROVE AVENUE ROSEMEAD. CALIFORNIA 91770 K. P. BASKIN TELEPHONE MANAGER, NUCLEAR ENGINEERING (213)572-1401 AND LICENSING June 9, 1980 U. S. Nuclear Regulatory Commission Office of Inspection and Enforcement Region V 1990 North California Boulevard Suite 202, Walnut Creek Plaza Walnut Creek, California 94596 Attention:
Mr. R. H. Engelken, Director DOCKET NO. 50-206 SAN ONOFRE -
UNIT 1
Dear Sir:
IE BULLETIN 80-06 ENGINEERED SAFETY FEATURE (ESF)
RESET CONTROLS Reference is made to your correspondence of March 13, 1980, forwarding IE Bulletin.80-06. Identified therein were inquiries concerning the effect of reset on the function of Engineered Safeguard Systems.
Responses to the individual items specified in the Bulletin are listed below:
ITEM 1 Review the drawings for all systems serving safety-related functions at the schematic level to determine whether or not upon the reset of an ESF actuation signal, all associated safety-related equipment remains in its emergency mode.
Response
Table I summarizes the results of a review of drawings for all systems connected to the ESF actuation/reset signal. Components not listed remain in the Emergency Mode on Reset.
An evaluation of each item indicates that the following actions are required.
8008 06006t
U. S. Nuclear Regulatory Commission I. E.Bulletin 80-06 Page 2 Component
- 1. No corrective action is required. Charging flow to the core via this path is not required during the injection phase of Safety Injection (SI). Since this path is in parallel to that of MOV 356, 357 and 358, adequate flow will reach the core even if FCV 1112 was closed. After reset of the ESF signal, this valve will be operated manually to provide a hot leg injection flowpath.
- 2. This is being corrected during the current refueling outage. Control of the reset of the recirculation valves will be by the position of the feedwater pump discharge valves instead of the ESF signal.
- 3.
No corrective action is required.
Once the emergency siren has started it will operate for the required 2 minute run independent of the ESF signal.
- 4. This is being corrected during the current refueling outage by requiring a manual reset in addition to reset of the ESF signal in order to restore electrical protection.
- 5. This is being corrected during the current refueling outage by requiring a manual reset in.addition to reset of the ESF signal in orderto restore electrical protection.
- 6. This is being corrected during the current refueling outage. Control of the reset of the recirculation valves (see 2 above) will be by the position of the feedwater pump discharge valves instead of the ESF signal.
- 7. This results in the addition of a small additional load (<30KW) to the diesel generator. Since reset occurs after start of major ESF loads, sufficient diesel generator capacity is available to carry the small additional load.
- 8. a. The bypass valves will be modified prior to return to service from the next refueling outage by installation of a seal in/reset scheme. During the interim period, the applicable Operating Instruction will be revised to require that the valve controller be put in the close position prior to reset of the ESF signal.
- b. No corrective action is required on FCV 456, 457 and 458 as MOV 21, 22 and 23 in the same lines are closed by the ESF signal.
- 9. No corrective action is required as this contact provides annunciation only. This annunciator should reset on ESF signal reset to inform the operators that reset has occurred.
- 10. No corrective action is required as once the event recorder has been initiated it will continue to operate until it times off or is manually reset. The information recorded by the event recorder is normally
U S. Nuclear Regulator mission I. E.Bulletin 80-06 Page 3 utilized in analyzing the first few minutes/seconds of a transient.
The recorder is for information only and has no control function.
- 11.
This is being corrected during the current refueling outage by installation of a seal in/reset circuit in the valve control scheme.
- 12. This is being corrected during the current refueling outage by installation of a seal in/reset circuit in the pump control circuit.
- 13. This is being corrected during the current refueling outage by installation of a seal in/reset circuit in the CSAS control scheme.
- 14. This item will be corrected prior to return to power from the next refueling outage by installation of a seal in/reset circuit. During the interim period, a caution note will be added to the applicable Operating Procedure alerting the operator that these electrical trips are reactivated on reset of the ESF signal.
ITEM 2 Verify the actual installed instrumentation and controls at the facility are consistent with the schematics reviewed in Item 1 above by conducting a test to demonstrate that all equipment remains in its emergency mode upon removal of the actuating signal and/or manual resetting of the various isolating or actuation signals. Provide a schedule for the performance of the testing in your response to.this Bulletin.
Response
A test demonstrating that the validity of the analysis presented above will be performed prior to the return to power from the current refueling outage.
ITEM 3 If any safety-related equipment does not remain in its emergency mode upon reset of an ESF signal at your facility, describe proposed system modifi cation, design change, or other corrective action planned to resolve the problem.
Response
Dur response to Item 1 above identified 14 areas where components do not remain in the Eergency Mode on ESF reset.
Of the 14 areas we have determined that no corrective action is required on areas 1, 3, 7, 8.b, 9 and 10. Our basis for this determination is discussed above.
Corrective action for areas 2, 4, 5, 6, 11, 12 and 13 were identified prior to the issuance of the subject Bulletin and corrective action will be completed and included in the test program as discussed in response to Item 2 above prior to return to power following the current refueling outage.
U. S. Nuclear Regulatory mmission I. E.Bulletin 80-06 Page 4 Corrective action for areas 8a and 14 has been identified as a result of the review required by Item 1 of the Bulletin. The corrective action shown above will be implemented during the next outage of sufficient length to permit accomplishment of the work following the current refueling outage and after required engineering and procurement actions have been completed, but not later than prior to return to service from the next refueling outage.
ITEM 4 Report in writing within 90 days, the results of your review and include a list of all.devices which respond as discussed in item 3 above, actions taken or planned to assure adequate equipment control, and a schedule for implementation of corrective action. This information is requested under the provisions of 10 CFR 50.54(f).
Accordingly, you are requested to provide within the time period specified above, written statements of.the above information, signed under oath or affirmation.
Reports shall be submitted to the Director of the appropriate NRC Regional Office and a copy shall be forwarded to the NRC Office of Inspection and Enforcement, Divison of Reactor Operations Inspection, Washington, D.C. 20555.
Response
This letter constitutes our response to item 4.
Should you have any questions regarding this matter, please contact me.
Subscribed on this
/?R day of 1980.
By________
K. P. Baskin Manager, Nuclear Engineering and Licensing Subscribed and sworn to before me on this OFFIIAL SEALdy f190 AGNES CRABTREE
_ _day of 1980.
NOTARY PUBLIC - CALIFORNIA PRINCIPAL OFFICE IN LOS ANGELES COUNTY My Commission Exp. Aug.27, 1982 Notary./Public in and for the County of Los Angeles, State of California cc:
Director, Nuclear Safety Analysis Center (1)
Director, Office of Inspection and Enforcement (1)
U. S. Nuclear Regulatory Commission I. E.Bulletin 80-06 TABLE I COaMPONENTS CONNECTED TO THE ESF ACTUATION/RESET SIGNAL WHICH DO NOT REMAIN IN DERGENCY MODE OR RESET COMPO-SEQUENCER CCMPONENT(s)
EMERGENCY EFFECT EFFECT ON NENT #
CONTACT #
CONTROLLED MODE OF RESET PLANT/ESF SYSTEM1 1
l-Bl FCV-1112 Open Valve returns to auto None.
Flow to core charging control via this path is not required during the injection phase of SI.
2 1-B7 CV 875 A, B Open Closed Recirculation Feedwater System routed to condenser recirculation to instead of RWST.
IST 3
1-Bll Emergency Start 2 minute None None 2-Bll Siren timer.
4 1-B16 SI Pump Blocks electrical Restores trip Would trip pump if 2-B16 protection trips an electrical trip had occurred during ESF actuation.
5 1-B17 Feedwater Pump Blocks electrical Restores trip Would trip pump if 2-B17 protection trips an electrical trip had occurred during ESF actuation.
6 1-Cl CV 37, 38 Closed Reopen Routes feedwater 2-Cl Feedwater pump recirculation recirculation to to condenser condenser instead of RNST.
TABLE I Page 2 COMPO-SEQUENCER COMPONENT(s)
EMERGENCY EFFECT EFFECT ON NENT #
CONTACT #
CONTROLLED MODE OF RESET PLANT/ESF SYSTEM 7
1-A13A Motor heater Off Motor heater for Small aditional load 2A-15A panels secured components on diesel generators will restart.
8 1-AlC,1-A-2C
- a.
CV 142,143,144 Closed Would reopen as If a single failure l-A3C,2-A-lC b. FCV 456,457 directed by Feedwater of a feedwater pump 2-A2C FCV 458, Control System discharge valve has 2-A3C Feedwater occurred, Borated k
Control Valves water will flow tow steam generators.
9 l-A5C SI Alarm Alarm Clear Alarm None-Annunciator only 2-A56 10 l-Al5C Event Recorder Initiate Remove initiate signal None-Once recorder 2-Al5C Initiate initiates it either times out or is manually stopped.
11 1-Al7C CV202,203,204 Closed Could reopen if control Letdown restored 2-Al7C Letdown orifice switch had been OPEN.
isolation This is the normal mode.
12 1-D3 Standby charging Block out start of Restore auto start of If in service pump pump auto start standby pump standby pump fails due to. low block suction pressure standby pump could also start and fail.
13 1-D5 Containment Spray ON OFF Containment Spray 2-D5 Actuation System actuation removed.
14 l-A9A-3 Diesel Generator Block some Restore trips If a blocked 2-AllA-1 electrical trip electrical trips electrical trip had occurred, electrical trip would occur.