ML17291B088

Responds to GL 95-07 & Provides Requested Info Re Implementation Actions & Completion Schedule

ML17291B088
Person / Time
Site:	Columbia
Issue date:	10/13/1995
From:	Parrish J WASHINGTON PUBLIC POWER SUPPLY SYSTEM
To:	NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
References
GL-95-07, GL-95-7, GO2-95-221, NUDOCS 9510250151
Download: ML17291B088 (12)

Text

RIORITY CCELERATED RZDS PROCESSZNG)

REGULATORY INFORMATION DISTRIBUTION SYSTEM (RIDS)

ACCESSION NBR:9510250151 DOC.DATE: 95/10/13 NOTARIZED- YES DOCKET FACIL:50-397 WPPSS Nuclear Project, Unit 2, Washington Public Powe 05000397 AUTH. NAME AUTHOR AFFILIATION PARRISH,J.V. Washington Public Power Supply System R RECIP.NAME RECIPIENT AFFILIATION Document Control )branch (Document Control Desk)

SUBJECT:

Responds to GL 95-07 & provides requested info re implementation actions & completion schedule.

DISTRIBUTION CODE- A056D COPIES RECEIVED:LTR ENCL SIZE:

TITLE: Generic Ltr 95-07 Pressure Locking & Thermal Banding of Safety Rela R NOTES RECIPIENT COPIES RECIPIENT COPIES ID CODE/NAME LTTR ENCL ID CODE/NAME LTTR ENCL NRR/DRPE/PDl-1 1 1 PD4-2 PD 1 1 CLI 1 1 INTERNAL: E CENTER 0 1 1 NRR/EMEB/B 1 1 EXTERNAL: NO C 1 1 NRC PDR 1 1 NUDOCS ABSTRACT 1 1 D

N NOTE TO ALL "RZDS" RECZPZENTS:

PLEASE HELP US TO REDUCE WASTE! CONTACT THE DOCUMENT CONTROL DESK, ROOM OWFN 5DB (415-2083) TO ELZMZNATE YOUR NAME FROM DZSTRZBUTZON LZSTS FOR DOCUMENTS YOU DON'T NEED!

TOTAL NUMBER OF COPIES REQUIRED: LTTR 8 ENCL 8

0 si WASHINGTON PUBLIC POWER SUPPLY SYSTEM PO. Box 968 ~ 3000 George Washington Way ~ Richland, Washington 99352-0968 ~ (509) 372-5000 October 13, 1995 G02-95-221 Docket No. 50-397 U. S. Nuclear Regulatory Commission Attn: Document Control Desk Washington, D. C. 20555 K

Gentlemen:

Subject:

WNP-2, OPERATING LICENSE NO. NPF-21 RESPONSE TO GENERIC LETTER 95-07, "PRESSURE LOCKING AND THERMAL BINDING OF SAFETY-RELATED POWER-OPERATED GATE VALVES"

Reference:

NRC Generic Letter 95-07, dated August 17, 1995, "Pressure Locking and Thermal Binding of Safety-Related Power-Operated Gate Valves" The Supply System hereby responds to the referenced generic letter and provides the requested information regarding implementation action(s) and completion schedule. In the generic letter, the NRC staff requested a preliminary evaluation of pressure locking and thermal binding of safety-related power-operated gate valves and, subsequently, a more detailed evaluation and resolution of the issue. The Supply System will implement the requested actions described in the generic letter. However, the completion schedule has been amended consistent with evaluations already completed and the potential safety significance associated with the requested evaluations.

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response and dfiHi commitment h bj schedule:

g "Within 90 days of the date of this generic letter, each addressee of this generic letter is requested to perform and complete the following actions:

Perform a screening evaluation of the operational configurations of all safety-related power-operated (i.e., motor-operated, air-operated, and hydraulically operated) gate valves to identify those valves that are potentially susceptible to pressure locking or thermal binding; and l (gQQ Q 9510250151 951013 PDR ADaCK O5OOO397

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Page 2 RESPONSE TO GENERIC LETTER 95-07

2. Document a basis for the operability of the potentially susceptible valves or, where operability cannot be supported, take action in accordance with individual plant Technical Specifications."

Su 1 tern Re ns nd Sched le The Supply System has performed a susceptibility screening evaluation of safety-related power-operated gate valves that are potentially susceptible to pressure locking or thermal binding. A comprehensive review of the motor-operated gate valves installed at WNP-2 was performed jointly by the Supply System and a contracted valve expert to determine those valves susceptible to pressure locking or thermal binding. The results of the review showed that no valves were significantly susceptible to thermal binding.

However, seven valves were identified that should have a disk bypass modification to prevent pressure locking. Three of the seven valves have been modified. The remaining four valves were subsequently shown to be acceptable without modification. Nine additional valves were identified as being marginally susceptible to pressure locking.

These valves were typically small valves subject to low differential pressure during design basis conditions. Subsequent calculations showed all nine valves to be acceptable.

One additional valve was identified as being susceptible to pressure locking during test conditions. Testing procedures were changed to preclude the potential for pressure locking. The calculations demonstrating the capability to overcome'pressure locking were performed using industry accepted methodology.

The motor-operated gate valves identified as being susceptible (or marginally susceptible) to pressure locking are documented in WNP-2 Pressure Locking and Thermal Binding (PLTB) Report WPPSS-ENT-0136, issued December 29, 1993. Safety-related air and hydraulically operated gate valves were subsequently evaluated for susceptibility to pressure locking or thermal binding and none were identified as being susceptible.

Operability evaluations of the potentially susceptible motor-operated gate valves were performed and the bases are documented in Problem Evaluation Report (PER) 294-0074, dated February 1, 1994. These valves were determined to be operable. Therefore, the 90-day requested actions are complete. A copy of the PLTB report and PER 294-0074 were presented to the NRC inspectors during a preliminary Generic Letter 89-10 closeout inspection (NRC Inspection 95-24) in July 1995.

yh ill lgh ld h lhd-dy~Ai dll ll h hj g (pp. 6) and includes the Supply System response and commitment schedule:

"Within 180 days of the date of this generic letter, each addressee of this generic letter is requested to implement and complete the guidance provided in Attachment 1 to perform the following actions:

Page 3 RESPONSE TO GENERIC LETTER 95-07

1. Evaluate the operational configurations of safety-related power-operated (i.e., motor-operated, air-operated, and hydraulically operated) gate valves in its plant to identify valves that are susceptible to pressure locking or thermal binding;

2. Perform further analyses as appropriate, and take needed corrective actions (or justify longer schedules), to ensure that the susceptible valves identified in 1 are capable of performing their intended safety function(s) under all modes of plant operation, including test configuration."

m Re n e nd chedule The Supply System will re-evaluate the screening criteria already used at WNP-2 to identify safety-related power-operated valves that are susceptible to pressure locking or thermal binding in accordance with Attachment 1 of the generic letter and as discussed during NRC Inspection 95-24. This action will be completed by July 15, 1996.

Corrective actions will be taken as appropriate for any additional valves determined to be susceptible to pressure locldng or thermal binding. The Supply System will schedule corrective actions commensurate with safety significance.

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6 and 7) and includes the Supply System response and commitment schedule:

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"Alladdressees, including those who have already satisfactorily addressed pressure locking and thermal binding for MOVs [motor-operated valves] by implementing the guidance in Supplement 6 to GL 89-10 (or equivalent industry methods), are requested to provide a summary description of the following:

The susceptibility evaluation of operational configurations performed in response to (or consistent with) 180-day Requested Action 1, and the further analyses performed in response to (or consistent with) 180-day Requested Action 2, including bases or criteria for determining that valves are or are not susceptible to pressure locking or thermal binding;

2. The results of the susceptibility evaluation and the further analyses referred to in 1 above, including a listing of the susceptible valves identified;

3. The corrective actions, or other dispositioning, for the valves identified as susceptible to pressure locking or thermal binding, including: (a) equipment or procedural modifications completed and planned (including the completion schedule for such .

actions); and (b) justification for any determination that particular safety-related power-operated gate valves susceptible to pressure locking or thermal binding are acceptable as II

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Page 4 RESPONSE TO GENERIC LETTER 95-07 I emRe ne nd h le The Supply System willprovide summary descriptions of the actions taken in accordance with the 180-day Requested Actions 1 and 2. A listing of the valves found susceptible to pressure locking or thermal binding will also be provided, including a description of the corrective actions, or other dispositioning, identified. This information will be provided by July 15, 1996.

The following provides the 60-day Re uired Re nse criteria defined in the subject generic letter (pp. 7) and includes the Supply System response and commitment schedule:

"Within 60 days from the date of this generic letter, a written response indicating whether or not the addressee will implement the action(s) requested above. If the addressee intends to implement the requested action(s), provide a schedule for completing implementation. If an addressee chooses not to take the requested action(s), provide a description of any proposed alternative course of action (if applicable), and the safety basis for determining the acceptability of the planned alternative course of action;"

Su I s em Res n e and chedule This letter satisfies the criteria and 60 day submittal schedule.

The following provides the 180-day Re uired Re n e criteria defined in the subject generic letter (pp. 7) and includes the Supply System response and commitment schedule:

2. "Within 180 days from the date of this generic letter, a written response to the information request specified above."

Su 1 stem Res onse and Schedule The Supply System will provide a re-evaluation summary of the current power-operated gate valve pressure locking and thermal binding susceptibility screening program. This written response will include summary descriptions of the actions taken in accordance with the 180-day Requested Actions 1 and 2, a listing of the valves found to be susceptible to pressure locking or thermal binding, and a description of the corrective actions, or other dispositioning, identified. Since the content of the written response is dependent on the Requested Actions and Information specified in the generic letter, the submittal schedule must be based on the scheduled completion of tasks not yet identified.

Therefore, the requested response will be submitted by July 15, 1996.

With the information contained in this submittal and its identified commitments, the Supply System considers the requests specified in Generic Letter 95-07 to be complete.

Page 5.

RESPONSE TO GENERIC LETTER 95-07 Should you have any questions or desire additional information regarding this matter, please call me or D. A. Swank at (509) 377-4563.

Sincerely, V. Parrish (Mail Drop 1023)

Vice President, Nuclear Operations CDM/ml CC: LJ Callan - NRC RIV KE Perkins, Jr. - NRC RIV, Walnut Creek Field Office NS Reynolds - Winston & Strawn JW Clifford - NRC DL Williams - BPA/399 NRC Sr. Resident Inspector - 927N

STATP. OF WASHINGTON )

Subject:

Response to Generic Letter 95-07, r ) "Pressure Locking and Thermal Binding COUNTY OF BENTON ) of Safety-Related Power-Operated Gate "Valves I, J. V. PARRISH, being duly sworn, subscribe to and say that I am the Vice-President, Nuclear Operations for the WASHINGTONPUBLIC POWER SUPPLY SYSTEM, the applicant herein; that I have the full authority to execute this oath; that I have reviewed the foregoing; and that to the best of my knowledge, information, and belief the statements made in it are true.

DATE , 1995 J . Parrish, Vice-President uclear Operations On this date personally appeared before me J. V. PARRISH, to me known to be the individual who executed the foregoing instrument, and acknowledged that he signed the same as his free act and deed for the uses and purposes herein mentioned.

GIVEN under my hand and seal this ~today of 1995.

Notary Public in and for the STATE OF WASHINGTON Residing at My Commission Expires

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