ML20071D133

Forwards Response to IE Bulletin 80-06 & SER Outstanding Issue 12 Re ESF Reset Controls.List of Equipment Which Returns to pre-LOCA State After Reset Encl

ML20071D133
Person / Time
Site:	Clinton
Issue date:	03/01/1983
From:	Wuller G ILLINOIS POWER CO.
To:	Schwencer A Office of Nuclear Reactor Regulation
References
REF-SSINS-6820 IEB-80-06, IEB-80-6, U-0605, U-605, NUDOCS 8303090206
Download: ML20071D133 (7)

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Blinois Power Company ug605

_33<03-01)6 500 SOUTH 27TH STREET, P. o. BOX 511, DECATUR, ILLINOIS 62525-1805 Docket Number 50-461 March 1, 1983 Director of Nuclear Reactor Regulation Attention Mr. A. Schwencer, Chief Licensing Branch No. 2 Division of Licensing U.S. Nuclear Regulatory Commission Washington, D.C 20555

References:

(1) IP Letter U-0355 from J. D. Geier to J. R. Miller, December 1, 1981; "IE Bulletin 80-06, Engineered Safety Feature Reset Controls."

(2) IP Letter U-0481 from G. E. Uuller to J. R. Miller, May 17, 1982; " Update of Earlier Submittal to Include Results of the Balance of Plant Review."

(3) NRC Letter from C. O. Thomas to G. E. Wuller, October 29, 1982. " Question Relating to the Loose Parts Monitoring System and IE Bulletin 80-06."

Clinton Power Station Unit #1 Engineered Safety Function Reset Controls (IE Bulletin 30-06)

(SER Outstanding Issue #12)

Illinois Power Company's (IP) original response to IE Bulletin 80-06 was provided in reference 1. Reference 2 was a follow-up letter to include the results of the Balance of Plant (BOP) review.

Reference Letter 3 provided IP with four questions from the staff regarding their review of our earlier tubmittals. The purpose of this letter is to transmit IP's responses to these four questions.

The first three questions deal with NSSS valves in the General ,

Electric (GE) scope of design. Of the nine valves covered in this category, IP is committing to make logic modifications for eight valves, requiring the operator to take deliberate operator action to open the valve after an isolation signal reset. For the remaining valve, justification is provided for the existing logic design. The last question deals with BOP equipment. In response to this question, IP is committing to revise the logic for 32 valves to bring them in compliance with IE Bulletin 80-06. In addition, justification is provided for the existing design for 14 valves that do not have a logic seal-in function.

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e L30-83(03-01)6 March 1, 1983 It is believed that the above information and commitments are adequate to close CPS-SER Outstanding Issue #12 in the next SER Supplement. Please let us know at your earliest convenience if you have any additional questions or concerns.

Sincerely,

. <$5 G. E. Uuller Supervisor-Licensing Nuclear Station Engineering AJH/jmm enclosure cc: H. Abelson, NRC Clinton Project Manager R. Kendall, NRC ICSB H. H. Livermore, NRC Resident Inspector Illinois Department of Nuclear Safety l

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Response to Questions on CPS-SER Outstanding Issue No. 12 Engineering Safety Features Reset Controls

1. Question:

Item 4f of letter U-0481 dated May 17, 1982 indicates that the RCIC inboard / outboard isolation valves (lE51-F063 and lE51-F064) reopen on a RCIC isolation signal reset. Will these valves be modified to require operator action to open them subsequent to the reset of~a RCIC isolation signal (consistent with the LRG-II response to item 4-ICSB; Volume 4 of the LRG-II Position Papers dated March 12, 1982)? If not, justify the existing design.

Response

Under the existing design, the RCIC inboard / outboard isolation valves (E51-F063 and E51-F064) reopen on a RCIC isolation signal reset. . This design has been evaluated against IE Bulletin 80-06 and it.has been determined that in order to gain compliance, these valves should be modified to require operator action to open them subsequent to the reset of the RCIC isolation signal.

This. modification is consistent with the LRG-II response in Position Paper 4-ICSB.

2. Question:

Why is it acceptable for RCIC suppression pool suction valve lE51-F031 to reopen on a RCIC isolation reset? ,

Response

It is acceptable for the RCIC suppression pool suction valve lE51-F031 to reopen as the result of RCIC isolation reset, because the only time the valve will open is when needed to meet an emergency situation. The operator will not reset the RCIC isolation reset unless the RCIC system is needed, and the valve will not open except to facilitate use of the RCIC system. lE51-F031 will not open unless the RCIC/HPCS storage tank level is at the low level setpoint or the suppression pool water level is at the high level setpoint. This logic is necessary for proper operation of the RCIC system. Requiring the operator to perform additional actions to open this valve is undesirable because of the delay it would cause in making the RCIC system available for use. This delay is further increased by the fact that this valve is slow opening (approximately 30 seconds).

3. Question:

The LRG-II response to item 4-ICSB identifies valves E12-F060A, B and E12-F075A, B (RHR Sample Line Valves) and B33-F019 and B33-F020 (Reactor Water Sample Valves) as reopening on an isolation signal reset. The LRG-II position is to modify the subject valve control circuits to require operator action to reopen these valves following a reset. These same valves exist at Clinton.

Describe the corrective actions planned to modify these valves or justify the existing design.

Response

Under the existing design valves E12-F060A, B and, E12-F075A, B (RHR Sample Line Valves) and B33-F019 a'nd B33-F020 (Reactor Water Sample Valves) reopen upon an isolation reset signal if they were opened originally.

This design has.been evaluated against IE Bulletin 80-06 and it has been determined that in order to gain compliance, these valves should be modified to require operator action to open them subsequent to the appropriate reset. This modification meets the requirements of NUREG-0737 Item II.E.4.2 and is consistent with the LRG-II response in Position Paper 4-ICSB.

4. Question:

Item 5 (BOP ESF) of letter U-0481 indicates that BOP safety-related equipment which has a prescribed mode during normal conditions may revert to this mode upon the ESF actuation condition returning to normal and the ESF actuation signal being reset. The staff is concerned that the protective actions of this equipment may be compromised once the associated actuation signal is reset. For example, although an initiating parameter may return to normal following an accident condition, equipment which changes state automatically on a reset could still lead to an unsafe condition. Therefore, identify each case 'qhere safety-related BOP equipment reverts to its normal mode on an ESF reset and either propose corrective actions to require operator action to realign this equipment following the reset, or justify the existing design.

4. Response:

Table 1 lists the Class IE non-NSSS electrical equipment that automatically reverts to the pre-LOCA condition after a general LOCA reset. The status of this equipment is contained in the following descriptions:

The logic for Component Cooling Valves 1CC071, 1CC072, ICC073, ICC074, and Process Sampling Valves 1PS003, 1PS004, 1PS005, 1PS009, 1PS010, 1PS016, 1PS017, 1PS022, 1PS031, 1PS032, 1PS034, 1PS035, 1PS037, 1PS038, 1PS043A, 1PS043B, 1PS044A, 1PS044B, 1PS047, 1PS048, 1PS055, 1P9056, 1PS069, 1PS070 will be modified to provide a_ seal-in on a LOCA signal.

The logic for Containment Combustible Gas Control Valves lHG001, lHG004, lHG005, and 1HG003 will be modified such that when the HG system is in either normal or test, the valves will close and seal-in on a LOCA signal. However, when the HG system is running, the valves will not close and seal-in on a LOCA signal, since the HG system is designed to operate under LOCA conditions.

Reactor Feedwater Valves 1B21-F032A and 1B21-F032B do not require a seal-in since these check valves are held in their LOCA position by system back-pressure, even if the LOCA signal is reset. No logic modification is necessary.

Fuel Pool Cooling Valves 1FC004A and 1FC004B automatically return to their pre-LOCA position after a general LOCA reset. During normal operations one of these valves is open and the other is closed. A LOCA signal causes the closed valves to open, and a LOCA reset causes it to close again. The valve previously open remains open.

Since during and after a LOCA only one open valve is required to provide sufficient fuel pool cooling, no logic modification is necessary.

Fuel Pool Cooling and Cleanup Valve 1FC038 isolates a safety related system from a non-safety related system.

It closes on a LOCA signal, and if the LOCA signal resets, it automatically reopens. If the non-safety related system fails during the LOCA and valve 1FC038 subsequently reopens, the non-safety related system remains isolated by means of a check valve on the downstream safety related side of valve 1FC038. No logic modification is necessary.

Fuel Pool Cooling and Cleanup Valves 1FC017 and 1FC023 close but do not seal-in on a LOCA signal. These valves isolate a safety related system from a non-safety related system. This same function is accomplished by valves 1FC016A, 1FC016B, 1FC024A, and 1FC024B which close on a LOCA signal and must be manually reset via a control switch after a general LOCA reset. Therefore valves 1FC017 and 1FC023 require no logic modification.

Suppression Pool Makeup Valves ISM 001A, 1SM001B, 1SM002A, and 1SM002B do not seal-in on a LOCA signal only. However on LOCA plus low suppression pool level signals these valves perform their safety function by sealing-in to dump the upper fuel pool into the suppression pool. There-fore, no logic modification is necessary.

Valves IVQ001A & IVQ001B are the drywell purge supply valves and valve IVQ005 is the drywell head exhaust valve.

These valves are closed and have administrative controls placed upon them-during normal plant operating modes (Operating conditions 1, 2 and 3). A seal-in feature in the logic for these valves is not needed since the valves would stay closed upon a LOCA signal and would stay closed following a general LOCA reset.

TABLE 1 EQUIPMENT WHICH RETURNS TO THE PRE-LOCA STATE AFTER A GENERAL LOCA RESET Schematic ' Schematic Equipment Diagram Equipment Diagram Number E02- 99 SH Number E02- 99 SH 1B21-F032A 1FW-24

• 1PS031 1PS-16 1B21-F032B 1FW-24 1PS032 1PS-17 1CC071 1CC-10 1PS034 1PS 1CC072 1CC-11 1PS035 1PS-17 1CC073 1CC-11 1PS037 1PS-16

-lCC074 1CC IPS038 1PS-17 1FC004A 1FC-9 1PS043A 1PS-16 1FC004B IFC-9 1PS043B 1PS-16 1FC017 1FC-10 1PS044A 1PS-17

' 1FC023 1FC-10 1PS044B 1PS-17 1FC038 1FC-10 1PS047 1PS-16 1HG001 lHG-4 1PS048 1PS-17 1HG004 1HG-5 1PS055 1PS-17 1HG005 lHG-6 1PS056 1PS-16 1HG008 lHG-7 1PS069 1PS-17

- 1PS003 1PS-17 1PS070 1PS-16 1PS004 1PS-16 ISM 001A ISM-1 1PS005 1PS-17 ISM 001B 1SM-2 l

1PS009 1PS-16 ISM 002A ISM-1 l 1PS010 1PS-17 ISM 002B 1SM-2

1PS016 1PS-16 1VQ001A. IVQ-6 j 1PS017 1PS-17 1VQ001B IVQ-4 1PS022 1PS-16 IVQ005 1VQ-4 2

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• The schematic diagram number would be read as E02-lFW99 sheet 24.

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