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Provides Addl Info Re Compliance W/Reg Guide 1.97 W/Respect to Containment Isolation Valve Position Indication & Request Approval for Deviation from Guidance
	ML20141K140
Person / Time
Site:	Waterford
Issue date:	05/23/1997
From:	Ewing E; ENTERGY OPERATIONS, INC.
To:	; NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
References
	RTR-REGGD-01.097, RTR-REGGD-1.097 W3F1-97-0120, W3F1-97-120, NUDOCS 9705280340
	Download: ML20141K140 (16)
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, E.ntergy ww*"""c-Killona. LA 70066 Tel 504 739 6242 Early C. Ewing, lil J

afety & Regulatory Af'arrs W3F1-97-0120 A4.05 PR May 23,1997 U.S. Nuclear Regulatory Commission ATTN: Document Control Desk Washington, D.C. 20555

Subject:

Waterford 3 SES Docket No. 50-382 License No. NPF-38 Supplemental Response to RG 1.97, Revision 3 Gentlemen:

On February 28,1991, Waterford 3 submitted to the NRC letter W3F1-91-0019 which documented compliance with Regulatory Guide 1.97, Revision 3. This submittal was approved by the NRC on July 12,1993. The purpose of this letter is to provide additional information regarding compliance with RG 1.97 with respect to containment isolation valve (CIV) position indication and request approval for deviation from the guidance provided in RG 1.97 for several CIVs.

Table 1 of the 1991 submittal states that position indication is provided for all automatic containment isolation valves. ANSI N271-1976," Containment Isolation Provisions for Fluid Systems," defines " automatic isolation valve" as a valve whose closure is initiated by automatic means without any action by a plant operator upon receipt of an isolation signal from a protection system. Waterford 3 only included automatic isolation valves (i.e. only those which receive an automatic closure signal) in the scope of RG 1.97 submittal. Containment isolation valves which do not receive an automatic closure signal (i.e. those with a primary safety function to open) were not included in the submittal. That decision is believed to have been based on the following types of statements in RG 1.97: "At the start of an accident, it may be difficult for the operator to determine immediately what accident has occurred. For this reason, reactor trip and certain other safety actuations (e.g. containment isolation) have been designed to be performed automatically during the initial stages of an accident."

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,; n Supplemental Response to RG 1.97, Revision 3 W3F1-97-0120 Page 2 May 23,1997 Waterford 3 believes the 1991 submittal was clear as to which CIVs were included in the scope (valves were listed by component number); however, the submittal did not specifically identify the valves that were excluded. Thus, it is not clear that the NRC concurred with this exclusion. RG 1.97 does not appear to give exemption for CIVs which do not receive an automatic closure signal. ANSI /ANS-4.5-1980, which is endorsed by RG 197, states that position indication should be provided for remotely-operated primary reactor containment isolation valve positions (closed /not closed).

We recognize that although a number of CIVs have open safety functions, there may be a point in the accident when these valves may need to be closed to preserve containment and thus perform a closed safety function. Based on the above, we have determined that these additional remotely-operated CIVs should be included in the scope of RG 1.97. A review of the CIVs at Waterford 3 showed that nearly all of the remotely-operated CIVs have qualified position indication in the control room, including those which have an open safety function. Attachment 1 provides a list of the remotely-operated CIVs which were not included in Waterford 3's RG 1.97 submittal in 1991 with the exception of CS-129 A&B, and NG-412 A&B, which are passive components and are discussed below. The valves in Attachment 1 will be added to FSAR Table 7.5-3, " Accident Monitoring Instrumentation". The only valves in Attachment 1 which do not have RG 1.97 qualified position indication are MS-116

--A&B and CVC-209, which are also discussed below.

CS-129 A&B are the Containment Spray Riser Check Valve Bypass _ Valves and are located inside containment. These valves are solenoid-operated, normally closed, and fail closed on a loss of power (see Attachment 2). The purpose of these valves is to enable indication of containment spray riser level to be taken, which is performed once per shift per the requirements of TS 3/4.6.2.1. Riser level instrumentation is provided upstream of check valve CS-128 A(B). A reading is taken by depressing a push-button on the local control panel (RAB wing area) which energizes and opens CS-129 A(B) thus bypassing the check valve CS-128 A(B) and allowing the level instrument to measure riser level. When the push-button is released, CS-129 A(B) will close. Position indication lights are provided on the local control panel for CS-129 A(B) to ensure the valves re-close when deenergized. This local position indication loop is safety class 1E qualified and operates from magnetic reed switches on the valves which provide positive indication of physical valve

_ position.

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L Supplemental Response to RG 1.97, Revision 3 l

W3F1-97-0120 Page 3 j~

May 23,1997 NG-412 A&B are the Steam Generator Nitrogen Supply Valves. These valves are l

motor-operated and are normally locked closed during plant operation. These valves are opened during shutdown conditions to provide a nitrogen blanket for the steam generators (see Attachment 3). These valves are provided with Non-safety 120V

Vital AC Uninterruptable position indication in the control room which is provided by limit switches on the valve. However, for the purpose of containment isolation, NG-412 A(B) are considered to be passive components. The locked closed position of I

these valves (i.e., braker maintained open) is controlled by OP-100-009, " Control of Valves and Breakers" and by OP-903-031, " Containment Integrity Check." OP-903-031 implements TS surveillance requirement 4.6.1.1.a which requires monthly verification of certain CIV positions, including NG-412 A&B This monthly check includes independent verification of valve position. OP-100-009 provides for independent verification to ensure the valves are returned to their locked closed j

positions after being opened. These administrative controls provides positive indication of valve position at all times, and ensure these valves are closed during l'

l plant operation assuring containment isolation.

RG 1.97 states that Type B variables are those variables that provide information to indicate whether plant safety functions are being accomplished. For the purposes of containment isolation, CS-129 A&B and NG-412 A&B are considered to be passive -

components. The status of the safety function (closed) for these valves is positively known prior to the accident, and these valves remain closed throughout the accident.

l Thus, these valves are not considered to fall within the scope of RG 1.97 requiring post accident monitoring instrumentation. This conclusion is consistent with the Bases of NUREG-1432, "CE Revised Standard TS," which states, "In the case of CIV position, the important information is the isolation status of the containment penetration. For containment penetrations with only one active PCIV having control room indication, a single channel of valve position indication is required to be OPERABLE. This is sufficient to redundantly verify the isolation status of each isolable penetration via indicated status of the active valve, as applicable, and prior knowledge of passive valve or system boundary status." Waterford 3 requests the NRC's concurrence with this conclusion.

i MS-116 A&B are the main steam atmospheric dump valves (ADVs) (see Attachment 3). These valves are containment isolation valves and do not have RG 1.97 qualified position indication in the control room. These valves fait closed on a loss of actuator power and do contain safety-related limit switches which provide open and closed position indication in the control room (indication is on the plant computer and is non-l safety-related). The closed limit switch also provides an annunciator in the control

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l Supplemental Response to RG 1.97, Revision 3 W3F1-97-0120 Page 4

- May 23,1997 room which indicates when the valve is not fully closed..The AC power supply for the annunciator is classified as non-safety, but is supplied by the emergency diesel generator and is backed up by safety-related, seismically qualified batteries for a l

. Loss of Offsite Power (Non-safety 120V Vital AC Uninterruptable). The cables in this loop are designed to IEEE-383. The loop does not specifically meet Safety Class 1E requirements in that the cables are routed through non-safety-related raceways (i.e.

do not meet 1E separation criteria). The cable trays for these non-safety raceways are seismically-mounted; however, portions of conduit traversing from one tray to another may not be seismically qualified. This annunciator, however, is considered to be a reliable source of direct position indication (closed /not closed status) for these valves. Position indication for the ADVs was discussed in a letter to the NRC dated March 31,1986 titled " Supplement to the Detailed Control Room Design Review Summary Report." In this letter it was noted that monitoring of steam generator pressure along with valve demand indication and valve travel limit indication provide reasonable approximations of valve position. Safety-related 1E indication as well as RG 1.97 Category 2 non-1E Vital indication of Steam Generator pressure is provided in the control room. Additional alternative means to determine if 1

the ADVs are performing their containment isolation function include safety-related 1E (ARMIRD5028, ARMIRD5031) and non-safety-related (ARMIRD5500 A&B) radiation monitors which are located near each ADV on the roof of the Reactor Auxiliary Building and would indicate radiation releases in the area. Based on the above, Waterford 3 believes the ADVs possess reliable position indication and sufficient alternate means of indication to determine valve status should they be required for containment isolation purposes during an accident. Waterford 3 requests the NRC's approval for deviation from the RG 1.97 qualification requirements for these valves based on the above.

CVC-209 is the charging system header containment isolation valve outside containment. This valve contains direct position indication in the control room (control panel CP-4) which is non-safety powered. Leakage past this valve from the

. RCS is not expected while the charging system is in operation since the charging pumps are positive displacement thereby providing a higher pressure in the charging lines than in the RCS. The charging system receives an automatic SIAS signal to L

start two charging pumps, align the system to take a suction on the Boric Acid l

Makeup Tanks and inject borated water into the Reactor Coolant System. Flow l

through this penetration is guaranteed in this line under post-LOCA conditions, and L

credit is taken for flow in the small break LOCA analysis. During the post-LOCA period, the water in the Boric Acid Makeup Tanks may be depleted. When this happens, charging will be secured and the charging isolation valves will be shut.

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Supplemental' Response to RG 1.97, Revision 3 W3F1-97-0120 Page 5 May 23,1997 The need to close CVC-209 for containment isolation would only be expected for a line rupture. For most RCS break locations, the charging line will not be exposed to the containment atmosphere, since flow from the Safety injection system keeps the piping covered with fluid. In the event the break was in the RCS Cold Leg at a position which caused the charging line to be exposed to the containment atmosphere, there are still several barriers available. Inside containment there are 2 I

' valves in series in each charging path and outside containment there are check valves on each charging pump discharge in addition to the containment isolation valve. The charging pumps are positive displacement pumps further minimizing any j

back flow in the system. All of the piping is of high pressure design, and tho vaives l

. are subject to ASME section XI testing.

Waterford 3 is implementing procedural guidance to manually isolate the upstream manual isolation valve CVC-208 should this penetration need to be isolated. CVC-j 208 has local mechanical position indication and is accessible post-accident (this

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action is discussed in letter W3F1-97-0107 submitted to the NRC on May 6,1997).

In addition, the inside containment isolation valves, CVC-216 A&B and CVC-218 l

A&B (see Attachment 4) contain qualified position indication in the control room.

l-Waterford 3 believes that the non-safety position indication for CVC-209, the l

qualified position indication for the inside CIVs, and the proceduralized action to manually shut CVC-208 provide positive assurance the CVC penetration status will be available should it be required during an accident. Waterford 3 requests the-NRC's approval for temporary deviation from the RG 1.97 qualification requirements for this valve until safety-related position indication can be provided to fully meet RG 1.97. This qualified position indication will be installed during Refueling Outage 9 (RF09), which is currently scheduled for the Fall of 1998.

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Supplemental Respr

, to RG 1.97, Revision 3 W3F1-97-0120 Page 6 May 23,1997 i

Should you have'any questions concerning the above please contact me at l

(504) 739-6242.

Very truly yours, l

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E.C. Ewing Director Nuclear Safety & Regulatory Affairs ECE/DFUssf Attachments cc:

E.W. Merschoff, NRC Region IV C.P. Patel, NRC-NRR J. Smith N.S. Reynolds NRC Resident inspectors Office t

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ATTACHMENT 1 SUPPLEnENTAL RESPONSE TO RG 1.97 REVtSION 3 ADOmONAL CONTANGENT ISOLATION VALVE POSmON DOICATIONS RG1.97 POWER NUheER SERtAL TYPE /

LOOP COMP SUPPLY OF SPDS NUh4hER VARIABLE CAT COMPONENT TYPE LOCATION ENV SEIS QA CLASS RANGEANTS CHANNELS llo N

021 CN1MT ISOL B1 MS IZSO401A S

RB B

A A

1E EnERG CLOSED NOT CLOSED 1NALVE MA MSWAAA401A EnERGENCYSG VLV POSmON NOT AVAAABLE I

CP4 FEED PUhr TUR8HES. NOTE 1,2.

021 CNTMT ISOL.

81 MS IZSO4018 S

RB B

A A

1E EnERG CLOSED NOT CLOSED 1NALVE MA MSWAAA4016 EnERGENCYSG VLV POSITION NOT AVA8.ASLE I

CP4 FEED PUhr TUR91NES. NOTE 1.2.

021 CNTMT ISOL 81 MS IZS0116A2 S

RS B*

B A

N1E VITAL - CLOSED NOT CLOSED 1NALVE MA MSWAAA116A ATMOSPHERIC VLV POSmON AlWUN. RA0781 1

CP4 STEAM DUhr. NOTE 12 021 CNTMT ISOL 81 MS IZS011882 S

R8 B*

B A

NIE VITAL CLOSED NOT CLOSED 1NALVE MA MSWAAAttG8 ATMOSPHERIC VLV POSmON ANNUN. N8791 1

CP4 STEAM Dt.2@. NOTE 12 021 CNTMT ISOL B1 CVRIZS01011/2 S'

ANN A

A A

1E VITAL CLOSED NOT CLOSED 1NALVE N/A CVRMVAAA101 CONTAMENT VLV POSmON NOT AVAA.ABLE I

CP-18 VACUUM REUEF. NOTE 1.

021 CNTMT ISOL B1 CVRIZS02011/2 S

ANN A

A A

1E VITAL CLOSED NOT CLOSED 1NALVE MA CVRMVAAA201 CONTAMENT VLV POSmON NOT AVAILABLE I

CP-18 VACUUM RELIEF. NOTE 1.

021 CNTMT ISOL B1 CClZS0007A1/2 S

ML20141K140

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