ML20093L285

From kanterella
Jump to navigation Jump to search
Requests Schedular Extensions Until 1985 Refueling Outage for Encl List of Electrical Components,Required to Be Environmentally Qualified Prior to Startup from 1984 Refueling Outage.Rev 1 to Justification for Operation Encl
ML20093L285
Person / Time
Site: Vermont Yankee File:NorthStar Vermont Yankee icon.png
Issue date: 07/25/1984
From: Hunter D
VERMONT YANKEE NUCLEAR POWER CORP.
To: Harold Denton
Office of Nuclear Reactor Regulation
References
FVY-84-92, NUDOCS 8407310353
Download: ML20093L285 (16)


Text

c. td

'\TI sill &IC)Pilf 'Y'/LPil(IIII NUCLEAR POWER CORPORATION FVY 84-92

.- RD 5, Box 169, Ferry Road, Brattleboro, VT 05301 y,gg iff July 25, 1984 ENGINEERING OFFICE 1671 WORCESTER ROAD

  • 7ELEPHONE 617-872-8100 United States Nuclear Regulatory Commission Washington, D. C. 20555 Attention: Mr. Harold R. Denton, Director Office of Nuclear Reactor Regulation

References:

(a) License No. DPR-28 (Docket No. 50-271)

(b) Letter, VYNPC to USNRC, FVY 84-34, dated April 11, 1984 (c) Letter, VYNPC to USNRC, FVY 84-81, dated July 10, 1984 (d) Letter, VYNPC to USNRC, FVY 84-90, dated July 19, 1984 (e) Letter, USNRC to VYNPC, NVY 83-192, dated August 19, 1983 (f) Letter, VYNPC to USNRC, Proposed Change No. 121 to Facility Operating License No. DPR-28, dated June 26, 1984 (g) Letter, VYNPC to USNRC, FVY 84-61, dated June 12, 1984 (h) Letter, VYNPC to USNRC, FVY 84-74, dated June 29, 1984

Subject:

Additional Requests for Schedular Extensions for Environmental Qualification of Certain Electrical Components at Vermont Yankee

Dear Sir:

In accordance with the provisions of 10CFR50.49(g), Vermont Yankee Nuclear Power Corporation hereby requests schedular extensions for certain clectrical components required to be environmentally qualified prior to chartup from our 1984 refueling outage, in accordance with the provisions of 10CFR50.49. A list of these components is provided in Enclosure 1 to this letter.

For each of the components listed in Enclosure (1), we have included a Justification for Continued Operation (JCO). In most cases, the associated JC0 was previously submitted to you in Enclosure (7) to the Vermont Yankee Upgraded Environmental Qualification (EQ) Program, which was forwarded by letter, dated April 11, 1984 [ Reference (b)]. However, for the purposes of cxpediting your review, all associated component JCOs are provided in Enclosure (2) to this letter. The components include:

o 6 motor operated valves f

o 4 solenoid valves o The Local Power Range Monitors (LPRds) and associated components o The Control Rod Position Indication proben and associated componento 8407310353 040725 )

PDR ADOCK 05000271 P PDR #

'0

p: ~

s United States Nuclear Regulatory Commission July 25, 1984 Attention: Mr. Harold R. Denton, Director Page 2 We are requesting schedular extensions for these components until no later than startup from our 1985 refueling outage which is presently scheduled to commence in early September 1985.

The basis for schedular relief is discussed in Enclosure (1). We trust that this information, coupled with the associated component JCO, provide an adequate basis for your approval of our extension requests. Because your review and approval of our requests is required prior to restart from our-present refueling outage, which is now scheduled for August 2,1984, we request your prompt attention to this matter.

The components listed in Enclosure (1) incorporate and supersede the component schedular extension requests forwarded to you by letters, dated July 10, 1984 [ Reference (c)], and July 19, 1984 (Reference (d)].

Finally, since the submittal of our Upgraded Environmental Qualification Pr) gram, we have continued our engineering effort to verify that all electrical components within the scope of 10CFR50.49 are environmentally qualified prior to startup from our 1984 refueling outage. With the exception of those components for which we are requesting schedular relief, to the best of our knowledge we will have ensured that all components within the scope of our Upgraded EQ Program comply with ths provisions of 100FR50.49 upon startup feom our present refueling outage.

We trust that this information is deemed acceptable; however, should you have any questions regarding this matter, please contact us. Your expedited review of our component schedular extension requests will be greatly appreciated.

Very truly yours, VERMONT YANKEE NUCLEAR POWER CORPORATION s /' I --

ac s

D. Hunter Vice President JBS/smh Enclosure L

f., ,

Enclosure (1)

VERMONT YANKEE NUCLEAR I

POWER CORPORATION 1

l SCHEDULAR EXTENSION REQUEST 8 FOR

! ENVIRONMENTAL QUALIFICATION OF CERTAIN l

ELECTRICAL COMPONENTS l

l i

l i

l l

l l

[

L t I

i Enclosure (1)

List of Vermont Yankee Environmental Qualification Program Electrical Components Reeutrina Schedular Extensions Justification ,

Reason for For Continued 1 Component TAG # Component Tyne Extension Request Operation Reference #

NOV-14-12A Motor-Operated Delivery 52 Valve j NOV-14-128 Motor-Operated Delivery 52 l

Valve NOV-13-15 Motor-operated See Note (1) 46 Valve l

NOV-10-135 Motor-Operated See Note (1) 68 Valve MOV-10-39A Motor-Operated See Note (1) 49 l Valve 1

NOV-10-32 Notor-Operated See Note (2) 43 Valve l

SE-10-4A Solenold-Operated See Note (3) 66 Valve SE-70-48 Solenold-Operated See Note (3) 66 Valve SE-70-4C Solenold-Operated See Note (3) 66 Valve SE-70-4D Solenold-Operated See Note (3) 66 Valve

- Local Power Range See Note (4) 39 Monitors (LPRMs)  :

- Control Rod See Note (5) 29 PosLtion Indication i

l i l

t

f Enclosure (1)

IL9191

1) During our field veriftention walkdowns performed during this outage, the serial numbers on the valves were discovered to be different than what our EQ records indicated.

The manufacturer is being contacted to determine the qualification status of these cctapenents.

2) This component is the inboard motor-operated isolation valve on the Residual Heat Removal (RHR) Head Spray line. The Head Spray line has been pomanently disconnected from the reactor vessel and is blanked off with a blind flange inside the drywell.

Because of this modification, Nov-10-32 is no longer requLeod to be leak rate tested in accordance with 10CFR, part 50, Appendix J, and is not withln the scope of our EQ program since it is no longer rolled upon for primary contalnment isolation. As described in Section 3.2 of the NRC'r Appendix J Safety EvaluatLon Report (SER), dated August 19, 1983

[ Reference (e)], Type C testlng Ln not required for lines forming a closed, seiselcally-qualified loop, with a water seat, within the Reactor But1 ding.

NOV-10-32 leak rate testing requirements have been deleted from our current AppendLx J Leak Rate Testing program. This program was submitted to thw NRC f or approval by letter, dated June 26, 1984 (Reference (f)]

and is currently under review.

3) Intended replae.ement component did not function properly during i post installation testing. Original component type has been re-innta11ed. We are present?,y uvaluating h resolution for this j component.
4) Local power Range Monitora (LpkH.)

The LpHMs provide neutron flux post-accident monitorinr. information to verify the reactor is shut down. Reactor shutdown will be verifled very shortly af ter scram signals are generated.

Due to a lack of qualification information, we have not been able to document the environmental qualification of the LpRMs.

We intsnd to investigate this problem further under our Regulatory cuide 1.97 Assessment program, being implemented in response to NURNG-0137 Supplement 1. As stated in our letter, dated June 12, 1984

, (Reference (g)), the results of our program, as well as a schedule for implementing any necessary component modifications, will be submitted to the NRC in October 1984, w _ _ ____ _ ___- _ _ _ _ _ _ _ _ _ _ _ _ - _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ . . _ _ _ _ _ - _ _ _ _ _ _ - - - . _ _ - - _ _ - _ _ _ _ _ _ _ _ _ _ -

(- .

Enclosure (1)

Netta (Continued) l

5) Control Rad Position Indication l The Control Rod Position Indication Probes and associated components provide information to verify a reactor scram. Reactor scram will be verified very shortly after scram signals are generated.

Due to a lack of qualification information, we have not been able to document the environmental qualification of this equipment.

We intend to investigate this problem further under our Regulatory Guide 1.97 Assessment Program, consistent with the schedule discussed in our letter dated June 12, 1984 [ Reference (g)).

1 l

l l

l I

l l

l i

i

Enclosure (2)

VERMONT YANKEE NUCLEAR POWER CORPORATION ENVIROIPGENTAL QUALIFICATION JUSTIFICATIONS FOR CONTINUED OPERATION (JCOs)

Revision 1 July 25, 1984 e

l l

L

. - . -.. .. - - . _ - , , . _ . . _ . . . - _ . , . . _ , , . _ _ . _ ~. . . . . . _ , , _ . . ,,

!~

]

l Enclosure (2)

Revision 1 JCO Index-Component / Service JC0 No.

Control Rod Drive System CR Position Information Components 29 Neutron Monitoring System LPRMs 39 Residual Heat Removal System MOV-10 -32 43 MOV-10-13B 68 MOV-10-39A 69 Reactor Core Isolation Cooling System NOV 13-15 46 Core Spray System MOV-14-12A, B S2 Service Water and Cooling Water System SE-70-4A, B, C, D 66

JC0 29 VERMONT YANKEE JUSTIFICATION FOR CONTINUED OPERATION COMPONENT: Control Rod Pos* tion Indication SYSTEM: Neutron Monitoring MANUFACTURER: General Electric MODEL:

LOCATION: Primary Containment FUNCTION: Reactor Shutdown Verification SERVICE: Fosition Indication and Acsociated Switches, Cables, and Connectors OUALIFICATION DISCREPANCY:

Lack of qualification documentation.

. JUSTIFICATION FOR CONTINUED OPERATION:

For a BWR, core reactivity design is such that it is shut down with rods-in.

This is verified within seconds after a scram. Rod position does not need to be known af ter that , as rods cannot be withdrawn.

It is our engineering judgement that this equipment will function post-LOCA to provide verification of rods-in within seconds after a scram. Subsequent loss of indication is not relevant.

Backup indication is provided by neutron monitoring.

Therefore justification for continued cperation is justified, b

JC0 39 VERMONT YANKEE JUSTIFICATION FOR CONTINUED OPERATION COMPONENT: Local Power Range Monitors (LPRM)

SYSTEM: Neutron Monitoring MANUFACTURER: General Electric MODEL: 729E989P6 LOCATION: Primary Containment FUNCTION: Reactor Shutdown Verification SERVICE: LPRMs and Associated Cables cnd Connectors QUALIFICATION DISCREPANCY:

Lack of qualification documentation.

JUSTIFICATION FOR CONTINUED OPERATION:

The LPRMs are designed to provide local power indication in the power range.

They can indicate that the reactor is shutdown by showing zero power, but this is not definitive.

For a boiling water reactor, the core reactivity design is such that it is shut down at any temperature and pressure with control rods inserted.

Therefore, the only indication that an operator needs is rod position at full-in. The rod position indication system provides this, and rods-in is quickly verified by operators after a scram. After that, they do not need to know rod position, as rods cannot be withdrawn.

The LPRMs are backup indication to rod position, and are also consulted within seconds after a scram. They are not required after that. It is our engineering judgement that this equipment will function to provide verification of reactor shutdown prior to any environmental degradation post-LOCA.

Therefore, continued operation is justified.

JC0 43 VERMONT YANKEE JUSTIFICATION FOR CONTINUED OPERATION COMPONENT: Motor-Operated Valve SYSTEM: RHR MANUFACTURER: Limitorque MODEL: SMB-00 LOCATION: Primary Containment (Volume PC)

FUNCTION: RHR Head Spray Isolation SERVICE: MOV-10-32 I I

OUALIFICATION DISCREPANCY:

No radiation data available.

JUSTIFICATION FOR CONTINUED OPERATION:

The RHR head spray valve's only purpose is to provide containment isolation.

The head spray line is blanked off inside the drywell.

l l

A second qualified valve, NOV-10-33, is in series with this valve and is located in the Reactor Building (Volure 21). Both these valves are normally closed during operation.

The blanking off of the line serves as a second alternative piece of equipment which accomplishes the safety function.

Therefore, justification for the continued safe operation of the plant is demonstrated.

I.

Q.. _

JCO 68 VERMONT YANKEE JUSTIFICATION FOR CONTINUED OPERATION COMPONENT: MOTOR-OPERATEP VALVE SYSTEM: -RHR MANUFACTURER: Limitorque MODEL:

LOCATION: Reactor Building (Volume 32)

FUNCTION: "B" RHR Pump Suction From Torus SERVICE: MOV 10-13B OUALIFICATION DISCREPANCY:

Lack of documentation on motor.

JUSTIFICATION FOR CONTINUED OPERATION:

This valve is normally open and during an accident it would remain in the open position. Failure of the motor will not cause the valve to close.

Although for long-term LOCA flexibility, it may be desirable to operate this valve, all essential accident safety functions are normally performed with this valve open.

This valve services the "B" RHR pt.mp of the "B" RHR Subsystem. A qualified "D" RHR pump, which operates in parallel with the "B" pump, is availablo.

Therefore, justification for the continued safe operation of the plant is demonstrated.

i I

l

. l u_

c JCO 69 '

VERMONT YANKEE JUSTIFICATION FOR CONTINUED OPERATION COMPONENT: MOTOR-OPERATED VALVE SYSTEM: RHR MANUFACTURER: Limitorque MODEL:

LOCATION: Reactor Building (Volume 46)

FUNCTION: "A" RHR Torus Cooling and Spray Outboard Isolation SERVICE: MOV 10-39A QUALIFICATION DISCREPANCY-Lack of documentation.

JUSTIFICATION FOR CONTINUED OPERATION:

This valve is normally closed and is required to open shortly after an accident for Torus Cooling and spray functions.

It is likely that Torus Cooling will be initiated within ten (10) minutes after an accident in which blowdown to the Torus is involved. The environmental stress received by this valve within the first ten (10) minutes of an accident should not prevent it from opening in our judgement.

If this valve fails to operate properly during an accident, the redundant, qualified "B"-RHR Torus Cooling Subsystem is also available.

Therefore, justification for the continued safe operation of the plant is demonstrated.

l l

i

. .lCO 46 VERMONT YANKEE JUSTIFICATION FOR CONTINUED OPERATION COMPONENT: Motor-Operated Valve SYSTEM: RCIC MANUFACTURER: Limitorque MODEL: SMB-000 LOCATION: Primary Containment FUNCTION: Inboard RCIC Steam Isolation SERVICE: MOV-13-15 OUALIFICATION DISCREPANCY:

No radiation data on motor. .

JUSTIFICATION FOR CONTINUED OPERATION:

This valve isolates the RCIC steam line following any event where isolation is required. Failure of the motor due to radiation damage will result in the valve failing "as is". Normally this valve is open, and it is required to close immediately following a RCIC break, immediately following a large LOCA, and approximately 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> following a small LOCA.

MOV-13-16 which, although not qualified, receives significantly less radiation, is in series with this valve and receives the same automatic isolation signals. There are other valves, which are not required to be qualified, in series located near the RCIC turbine which can isolate steam to the turbine. These valves require operator action to actuate them.

It is highly unlikely that this valve will fail as a result of radiation damage. The incramental increase in accumulated radiation dose from a large

' break LOCA should not prevent valve closure since the valve operates within the first minutes of the accident.

Thereforc, justification for the continued safe operation of the plant is demonstrated.

l' L

1 JCO 52 VERMONT YANKEE JUSTIFICATION FOR CONTINUED OPERATION COMPONENT: Motor-Operated Valve SYSTEM: Core Spray MANUFACTURER: Limitorque MODEL: SMB-2 LOCATION: Reactor Building (A-Volume 23. B-Volume 29)

FUNCTION: Core Spray Injection SERVICE: MOV-14-12A NOV-14-12B OUALIFICATION DISCREPANCY:

No radiation data on motor and motor brake.

JUSTIFICATION FOR CONTINUED OPERATION:

These valves are normally closed and are required to automatically open to inject core spray water into the reactor vessel following a LOCA. Valve 12A is in the "A" Core Spray Train, and 12B is in the "B" Train.

The core spray systems function as backups to the LPCT Systems.

There is no radiation data available on the motor or motor brake. Failura of these components would result in the valve not opening or only partially opening.

The valves are located in an area which normally has low radiation level and they open in the first minutec following a large LOCA before a harsh radiation environment develops. It is highly unlikely that they will fail due to the incremantal increase in accumulated radiation dose from a large break LOCA.

Subsequent repositioning of the valves could be desirable during the long-term courec of the event but this is not essential.

Therefore, justification for the continued safe operation of the plant is demonstrated.

u. l

JC0 66 VERMONT YANKEE JUSTIFICATION FOR CONTINUED OPERATION COMPONENT: Solenoid-Operated Valve SYSTEM: Residual Heat Removal Service Water Cooling MANUFACTURER: ASCO MODEL: HPX-8211 C13 LOCATION: Reactor Building (see Service) Elevation 232'-6" FUNCTION: RHR Service Water Pump Motor Cooling SERVTCE: SE-70-4A (Volume 45)

SE-70-4B (Volun.e 4 7)

SE-70-4C (Volume 45)

SE-70-4D (Volume 47)

OUALIFICATION DISCREPANCY:

No qualification documentation available.

JUSTIFICATION FOR CONTINUED OPERATION:

Each of these valves supply cooling water to their respective RHR service watcr cooling pump motor thrust bearing. Motor cooling is required when the pump is operating.

These solenoids are energized to close. Electrical failure of the solenoid will result in the vpening of the solenoid valve which is the desired fail-safe position.

Each solenoid has a manual bypass valve which could be opened if the area was accessible.

In the absolute worst case scenario these valves are exposed to an environment which gradually heats up to a maximum of 1040 F at ambient pressure and relative humidity. The worst case radiation exposure af ter 40 years plus 1 year post-accident is only 1.3 x 106 rads.

The harsh environment for which this equipment must be qualified results from low probability events.

Therefore, justification for the continued safe operation of the plant is demonstrated.

i

%_