ML18139A378

Responds to IE Bulletin 80-06 Requesting Review of Drawings for All Sys Serving safety-related Functions at Schematic Level,Verification of Controls & Proposed Design Mods. Actions & Schedules Delineated in Item 3

ML18139A378
Person / Time
Site:	Surry, North Anna
Issue date:	06/12/1980
From:	Sylvia B VIRGINIA POWER (VIRGINIA ELECTRIC & POWER CO.)
To:	James O'Reilly NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II)
References
421, IEB-80-06, IEB-80-6, NUDOCS 8006300349
Download: ML18139A378 (10)

Text

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• e VIRGINIA ELECTRIC AND POWER COMPANY RICHMOND,VIRGINIA 23261 i* .*

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Ju\ I June 12,1980 Mr. James P. O'Reilly, Director Serial No. 421

• Office of Inspection and Enforcement NO/RGS/jmj U.S. Nuclear Regulatory Commission Docket Nos 50..:280 Region II 50-281 101 Marietta Street, Suite 3100 50-338 Atlanta, Georgia 30303 50-339 License Nos. DPR-32 DPR-37 NPF-4 NPF-7

Dear Mr. O'Reilly:

IE BULLETIN 80-06 NORTH ANNA POWER STATION UNIT NOS. 1 AND 2 SURRY POWER STATION UNIT NOS. 1 AND 2 This letter is in response to IE Bulletin 80-06: "Engineered Safety Feature (ESF) Reset Controls".

We have completed our review of the subject bulletin and have determined that certain safety-related equipment does not remain in the emergency mode upon the reset of an ESF actuation signal. Until design modifications can be imple-mented, changes to station procedures have been made to incorporate the re-quirements that the safety-related equipment will remain in its emergency mode following the reset of an ESF signal.

NRC Request

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 emergency mode. in~

_/ II I Response I On November 6, 1979, during a review at our North Anna Power Station of syst~' /

.operation subsequent to a unit trip and safety injection actuation, it was discovered that certain safety-related equipment returned to its non-safety mode upon reset of an ESF actuation signal. This condition was reported to the NRC for Unit 1 pursuant to Technical *specification 6.9.1.8.i and for Unit 2 pursuant to 10 CFR 50. 55 (e)

• At that tim.e a review of the drawings for all systems serving safety-related functions was immediately initiated to determine if any other deficiencies existed. This review was performed by our architect ~ngineer and Vepco for North Anna.

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e VIRGINIA ELECTRIC AND POWER COMPANY TO e

Mr. James P. O'Reilly 2 When the discrepancies in the ESF control circuits were discovered at North Anna, we instructed our architect-engineer to review the control circuitry of ESF systems at Surry Power Station Units 1 and 2 to determine if similar problems existed at that facility.

The results of our review of North Anna and Surry drawings for all safety-related equipment serving as protective functions indicate that certain equipment will not remain in the emergency mode when the ESF actuation signal is reset. The affected control circuits are addressed in our response to Item 3 of the Bulletin.

NRC Request

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 resetti~g of the various isolating or actuation s.ignals. Provide a schedule for the per-formance of the testing in your response to this Bulletin.

Response

A review was performed by Vepco North Ann~ and Surry site personnel of station procedures used to verify that all safety-related equipment remains in its emergency mode upon the removal of ESF signals. The results of our.review are as follows:

.* North Anna Units 1 and 2

. -~

Test procedures for both units have been modified to demonstrate that all equipment remain in its emergency mode upon resetting of the actuation signals.

The following tests were modified:

.a. Safety Injection Functional Test

.b. Contairnnent Depressurization Actuation Functional Test Verification tests will be performed as a part of required system functional tests during the next unit refueling outage. The refueling outages for Units

. . ,. ~- 1 and 2 are scheduled for December 1980 and September 1981 respectively *

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• .-.... The following test will be developed to test main steam line isolation

• Main Steam Line Isolation Reset Test This test will also be performed during the refueling shutdown of the applicable

,. unit.

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It should be noted that individual control circuit tests have been performed on the modified circuits as listed in Item.3. These were performed as a part of the implementation of the design change.

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'~' e e VIRGINIA ELECTRIC AND POWER CoMPA1Y TO Mr. James P. O'Reilly 3 Surry Units 1 artd 2 The following test procedures have been modified for both units to demonstrate that all equipment remains in its emergency mode upon the resetting of the ESF actuation signals:

a. Safety.Injection Functional Test

b. Consequence Limiting Safeguards Functional Test Verification tests will be.performed as a part of required system functional tests during the next Unit 1 refueling outage scheduled for the fall of 1980 and prior to the Unit 2 start-up.

NRC Request

3. If any safety-related equipment does not remain in its emergency mode upon reset of an ESF s_ignal at your facility, describe proposed system modifi-cation, design change, or other corrective action planned to resolve the problem.

Response

It has been determined that design modifications should be made to certain safety-related equipment control circuits, as detailed below, to ensure that the equipment remains in its emergency mode upon the reset of an ESF signal.

NORTH ANNA UNIT NOS. 1 AND 2 Des_ign Change Implementation Component/System *problem *solution *schedule

1. Inside/Outside CDA Signal Add an auxiliary Design Change Recirc. Spray energizes a timer relay in parallel implementation Pumps after reset with timer and seal- completed.

time delay in CDA contact such timer starts that if CDA is reset pump. If the prior to timer starting CDA signal is pump, timer will remain reset before energized, the operator timer starts must place control switch the pump, the in "stop" or "Pull-to-pump will not Lock" Position to then start which is defeat pump starting.

its non-safe mode.

2. Control Room An S. I. signal Wire a*seal-in contact Design Change Supply and closes all AOD's such that when S.I. is implementation Exhaust AOD when S. I. is reset the S.I. output completed.

reset the A;OD's relay remains energized.

reopen. Manual reset switch from bottled air system used to return system to normal.

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e VIRGINIA ELECTRIC AND POWER COMPANY TO Mr. James P. O'Reilly e 4

3. Iodine Filter CDA s_ignal de- Added an auxiliary relay Des_ign Change Bank AOD's energizes SOV to* to seal-in CDA signal implementation admit air to such that operator must completed.

charcoal filter. also place AOD selector Resetting CDA swi.tch* in "Open" position signal re-energizes to reposition AOD's after SOV diverting air resetting CDA.

flow around ..

charcoal.filter.

4 *. Safeguards CDA signal de-* Added an auxiliary relay . . Design Change Area Exhaust energizes SOV to to seal-in CDA s_ignal. such implementation Fan Filter admit air to that operator must also completed.

SOV's charcoal filter. place AOD selector switch Resetting CDA in "Open" position tore-signal re-energizes position AOD after re-SOV diverting air setting CDA.

flow around charcoal filter.

5. Containment CDA signal trips . Removed auto start contact Des_ign Change Recirc *. the Containment on control switch from implementation Cooling fans Recirc. Cooling control circuit. This completed.

Fans, resetting forces operator to*

the CDA signal manually restart the fans restarts fan *. if required.

6. Service Water CDA signal operates A letter to the NRC from None required valves to

• associated SW . Vepco dated Dec *. 14, 1979 containment valves. Should discussing CDA/SI.reset Recirc *. Air Service Water mode modifications at North Coolers selector switch be *Anna 1 committed to using in Service Water administrative procedures position, resett~ng to adequately control these CDA will auto- devices.

matically shift valves to nonsafety mode.

7. Service Water CDA s_ignal. Utilize existing spare Des_ign Change

" Radiation energizes timer relay in MCC circuit to is to be Monitoring after reset

• seal-in CDA signal such implemented at Sample Pumps time delay timer that resetting CDA will .the next refueling

.starts pump. If not defeat pump.starting. outage.

.CDA signal is The operator must also reset before timer place pump selector switch starts pump, pump ** .in the "Stopf' position to will not start defeat.starting.

which is the nonsafe mode

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e e VIHGINIA ELECTRIC AND POWER COMPANY TO Mr. James P. O'Reilly 5 Design Change Implementation Component/System Problem Solution Schedule

8. Main Condenser Normally closed Install an additional Design Change Air Ej ec te>r to contaimnent relay & selector switch to be containment isolation valves to achieve the two implemented between condenser operator actions required at the next and contaimnent when resetting a safety refueling outage.

open on high signal.

radioactivity level in condenser and close on containment isolation Phase A (CI~A)

Problem arises when operator resets Contaimnent Isolation Phase A (CI-¢A) signal and containment isolation valves re-open.

9. Control Rod CDA signal Provide seal-in CDA Design Change Drive Cooling stops Control output relay in relay . is to be Fans Rod Drive cabinet and add reset implemented at Cooling Fans. switch such that operator the next Resetting CDA must reset CDA signal refueling outage signal starts and reset seal-in for Unit 1.

fans returning CDA output relays via Design Change them to non- .. reset switch. completed for safety mode. Unit 2.

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10. Turbine A SI signal Add relay to seal-in SI Design Change Driven starts pump. contact since resetting is to be Auxiliary Resetting SI SI will not.stop pump. implemented at Feedpump signal.stops Pump selector switch the next the pump, must also be placed refueling outage J*.!

returning in "stop" position to for Unit 1. *

• ...~:,. it to the non- stop pump

• Design Change

{ safetymode. completed for

§

'* Two delibrate -~ Unit 2.

operator.actions

,. should be required

~

t to return pump to I~

nonemergency *. mode.

11. Main.Steam With a main.steam Modify controlcircuit* Des_ign Change Line Trip line isolation for SOV' s such*- that *it

• is to be Valves SOV's signal, the trip will be necessary to implemented at valves will*. close.* press an open switch

• the next When CDA is reset~ . to break a seal-in refueling outage.

• \

• the trip valve

• of the sov to open'

.1'.:

will attempt to the trip valve.*

open which is the nonsafety mode.

VIRGINIA ELECTRIC AND POWER COMPANY TO e Mr. James P. O'Reilly e 6 SURRY UNITS NOS. 1 AND 2 Design Change Component/ Implementation System Problem Solution Schedule

1. Inside/Outside Resetting CLS The capability of re- None Required Rec ir. Spray signal before setting the CLS signal Pumps .time delay will prior to the completion defeat starting of the time delay may be of pumps. desirable, but could only occur if the containment-were subatmospheric which would not represent a safety hazard.

2. Control Room Control Room No problem None Required Supply and Ventilation exists with Exhaust MOV's Valves are present MOV's not AOD's circuits.

as on North Anna Units.

3. Iodine Filter Resetting CLS

• Auxiliary Modified circuits Bank AOD's signal will Building are to be divert air Ventilation installed in flow around System is the fall of 1980.

charcoal being filter. extensively modified.

Problem will be mitigated by administra-tive control in the interim.

4. Safeguards Resetting CLS Auxiliary Modified Area Exhaust signal will Building circuits Fan Filter divert air Ventilation are to be SOV's flow around System is being installed in charcoal extensively the fall of 1980.

filter. modified.

Problem will be mitigated 'by administrative control in the interim *

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VIHOINIA ELECTRIC AND POWER COMPANY TO e Mr. James P. O'Reilly e 7 j Design Change Component/ Implementation System Problem Solution Schedule

5. Containment Containment No problem None required Recirc. Recirc. Fans exists with Cooling Fans trip on CLS, present no auto start. circuits.

6. Service Water . No mode No problem None required Valves to selector exists with Containment switch is used. presen~

Recirc. Air The control circuits.

Coolers circuits operate properly.

No change in mode when the CLS signal is reset.

7. Service Water CLS Signal No problem exists None required Radiation starts Rad. with- present Monitoring Monitoring circuits.

Sample Pumps Pumps with no time delay in circuit. The CLS contact is sealed in by a starter contact, therefore resetting CLS signal causes no problem.

8. Main Condenser TV-SV-102 A containment isolation None required Air Ejector to will reopen valve has been Containment when CLS installed between the (both trains) containment and TV-SV-is reset with 102 which does not a high radiation receive an air ejector signal from high radiation signal.

condenser. This TV-SV-102 is no longer considered to be a containment isola-tion valve.

9. Control Rod These circuits No problem None required Drive Cooling contain no CLS exists with Fans inputs, only present manual on-off circuits.

selector switches.

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VIRGINIA ELECTRIC AND POWER ColNY TO Mr. James P. O'Reilly e 8 Design Change Component/ Implementation System Problem Solution Schedule

10. Turbine Driven An MOV and a No pr-0blem None required Auxiliary PCV are used to exists with Feedpump supply the motive present force to the Aux. circuits.

Feedpump (turbine driven). SI or CLS contacts are not used for pump start initiation.

11. Main Steam With CLS signal Modify control Design Change Line Trip initiated, the circuit for SOV's to be imple-Valve SOV's trip valves such that it will mented at the will close. be necessary to next refueling When CLS is reset the seal-in outage.

reset, the feature of the trip valves SOV to open should not attempt the trip valve.

to open as the Interim administra-Train A control tive procedures circuit is are being utilized designed with until the Design a seal-in Change can be function. implemented.

Should control power be lost to the Train A circuit, resetting the CLS signal will attempt to open the trip valves which is the nonsafe mode.

NRC Request

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 Division of Reactor Operations Inspection, Washington, D. C. 20555.

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> e e VIROINIA ELECTRIC AND POWER COMPA?IY TO Mr. Jame_s P. O'Reilly 9 t

Response

The actions taken or planned to assure adequate equipment control and a sche-dule for implementation of corrective action have- been delineated in our response to Item 3 of the subject Bulletin.

Very truly yours,

~RJ?:__

B. R~l::a --

Manager - Nuclear Operations and Maintenance cc: Mr. Victor Stello, Director NRC Office of Inspection and Enforcement Division-of Reactor Operations Enforcement Washington, D. C. 20555

COMMONWEALTH OF VIRGINIA )

) s. s.

CITY OF RICHMOND )

Before me, a Notary Public, in and for the City and Commonwealth aforesaid, today personally appeared B. R. Sylvia, who being duly sworn, made oath and said (1) that he is Manager-Nuclear Operations and Maintenance of the Virginia Electric and Power Company, (2) that he is duly authorized to execute and file the foregoing statements in behalf of that Company, and (3) that the state-ments are true to the best of his knowledge and belief.

Given under my hand and notarial seal this .*2 -th day of Jene My Commission expires  ; Ja 111/,T';Y 2/,, I 9L4 I *

(SEAL)

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