ML17328A818
| ML17328A818 | |
| Person / Time | |
|---|---|
| Site: | Cook  |
| Issue date: | 12/21/1990 |
| From: | Alexich M INDIANA MICHIGAN POWER CO. (FORMERLY INDIANA & MICHIG |
| To: | Murley T NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM) |
| References | |
| REF-GTECI-070, REF-GTECI-094, REF-GTECI-NI, TASK-070, TASK-094, TASK-70, TASK-94, TASK-OR AEP:NRC:1131, GL-90-06, GL-90-6, NUDOCS 9012260154 | |
| Download: ML17328A818 (10) | |
Text
ACCELERATED D TRIBUTION DEMONS TION SYSTEM REGULATORY XNFORMATION DISTRXBUTXON SYSTEM (RXDS)
DOCKET g
05000315 05000316 SUBZECT: Forwards response to Generic Ltr 90-06 re Generic Issue 70 on PORV
& block valve reliability & Generic Xssue 94 on addi low temp overpressure protection for LWRs.Tech Spec change will be proposed in early 1991.
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TITLE: Generic Ltr 90-06 Resolution of GE 70N94 PORVs
& Block Valve Relxabil A
NOTES ACCESSION NBR: 9012260154 DOC. DATE: 90/12/21 NOTARIZED: YES FACIL:50-315 Donald C.
Cook Nuclear Power Plant, Unit 1, Indiana 50-316 Donald C.
Cook Nuclear Power Plant, Unit 2, Indiana AUTH.NAME AUTHOR AFFILIATION ALEXXCH,M.P.
(formerly Indiana
& Michigan Ele RECIP.NAME RECIPXENT AFFILIATION MURLEY,T.E.
Document Control Branch (Document Control Desk)
I RECIPIENT ID CODE/NAME PD3-1 LA COLBURN,T.
INTERNAL KIRKWOODI R NLS 3 NRR/SRXB L
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1 RECIPIENT ID CODE/NAME PD3-1 PD NRR/EMEB PICKETT,D 13H15 RES/DSIR/EIB NUDOCS-ABSTRACT COPIES LTTR ENCL 1
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NOTE TO ALL"RIDS" RECIPIENTS:
PLEASE HELP US TO REDUCE WASTE! CONTACT THE DOCUMENT CONTROL DESK, ROOM P 1-37 (EXT. 20079) TO ELIMINATEYOUR NAME FROM DISTRIBUTION LISTS FOR DOCUMENTS YOU DON'T NEED!
TOTAL NUMBER OF COPIES REQUIRED:
LTTR 12 ENCL 12 D
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Power Company P.O. Box 16631 Columbus, OH 43216 8
AEP:NRC:1131 Donald C.
Cook Nuclear Plant Units 1 and 2
Docket Nos.
50-315 and 50-316 License Nos.
DPR-58 and DPR-74 RESOLUTION OF GENERIC ISSUE 70, "POWER-OPERATED RELIEF VALVE AND BLOCK VALVE RELIABILITY,"AND GENERIC ISSUE 94, "ADDITIONALLOW-TEMPERATURE OVERPRESSURE PROTECTION FOR LIGHT-WATER REACTORS,"
PURSUANT TO 10 CFR 50.54(f)
(GENERIC LETTER 90-06)
U.S. Nuclear Regulatory Commission Attn: Document Control Desk Washington, D.C.
20555 Attn: T. E. Murley December 21, 1990
Dear Dr. Hurley:
This letter is in response to Generic Letter 90-06 dated June 25, 1990.
Enclosure A of the Generic Letter presents the staff position and recommendations for the resolution of Generic Issue 70, "Power-Operated Relief Valves and Block Valve Reliability,"
applicable to Westinghouse-designed plants with power-operated relief valves (PORVs).
Enclosure B of the Generic Letter presents the staff position and recommendations for the resolution of Generic Issue 94, "Additional Low-Temperature Overpressure Protection for Light-Water Reactors,"
applicable to Westinghouse-designed
- plants, with or without PORVs and block valves.
Cook Nuclear Plant Units 1
and 2 were designed by Westinghouse and have three sets of PORVs and block valves.
Our response to these recommendations is provided in the attachment to this letter.
Technical Specifications changes will be proposed for Cook Nuclear Plant in response to Generic Letter 90-06.
We propose to submit the changes early in 1991 with the intent to implement them by the end of the 1992 refueling outages.
Once our actions are completed, we will have implemented the staff recommendations with three exceptions, which are discussed in the attachment.
One exception concerns incorporating valves in the PORV control air system into the IST Program (see response to Enclosure A, Action Item 2).
The second exception concerns the limiting condition for operation for three PORVs and associated block valves in Modes 1, 2, and 3 (see response to Enclosure A, Action Item 3).
The third exception concerns the applicability of low temperature overpressure protection (LTOP) in Mode 4 (see response to Enclosure B Action Item).
9012260154 90i221 PDR'- ADOCK 05000315 P -"'- --
--'PDR-
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Dr. T. E. Murley AEP:NRC:1131 This letter is submitted pursuant to 10 CFR 50.54(f) and, as such, an oath is enclosed.
Sincerely, M. P. Alexic Vice President ldp Attachments cc:
D. H. Williams, Jr.
A, A. Blind J.
R. Padgett G. Charnoff A. B. Davis - Regi.on III NRC Resident Inspector
- Bridgman NFEM Section Chief
Dr. T.
E. Murley AEP:NRC:1131 STATE OF OHIO)
COUNTY OF FRANKLIN)
Milton P. Alexich, being duly sworn, deposes and says that he is the Vice President of licensee Indiana Michigan Power Company, that he has read the foregoing Response to Generic Letter 90-06 and knows the contents thereof; and that said contents are true to the best of his knowledge and belief.
Subscribed and sworn to before me this ~~w day of 199 o OTARY PUBLIC BITA D, HlLL NOTARY PUBLIC. STAIE OF OHIO
A
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ATTACHMENT TO AEP:NRC 1131
RESPONSE
TO ACTIONS REQUESTED IN GENERIC LETTER 90-06
ATTACHMENT TO AEP:NRC:1131 PAGE 2
Enclosure A - Section 3.1 Staff Positions Resultin from Resolution of Generic Issue 70 "PORV and Block Valve Reliabilit "
Action Item 1 "Include PORVs and block valves within the scope of an operational quality assurance program that is in compliance with 10 CFR Part 50, Appendix B.
This program should include the following elements:
The addition of PORVs and block valves to the plant operational Quality Assurance List.
b.
Implementation of a maintenance/refurbishment program for PORVs and block valves that is based on the manufacturer's recommendations or guidelines and is implemented by trained plant maintenance personnel, C.
When replacement parts and spares, as well as complete components, are required for existing non-safety-grade PORVs and block valves (and associated control systems),
it is the intent of this generic letter that these items may be procured in accordance with the original construction codes and standards."
~Res ense This action is already established at Cook Nuclear Plant and includes the following elements, as requested:
a.
The PORVs and block valves are classified as QA-N in the plant Facility Data Base as a result of their pressure retaining function for the reactor coolant pressure boundary.
It should be noted that the classification does not necessarily apply to non-pressure retaining components on these valves, as well as actuators, motor operators and associated air and control systems.
b.
Maintenance of the PORVs and block valves has been performed to date, on an as-required basis, in accordance with manufacturer's recommendations and by trained plant personnel.
This will be enhanced during 1991 when the PORVs and block valves will be evaluated during the reliability-centered maintenance analysis of the reactor coolant system as part of our preventive maintenance upgrade program.
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I ATTACHMENT TO AEP'NRC'1131 PAGE 3
C.
Pressure retaining components of the PORVs and block valves have been and will continue to be procured in accordance with original construction codes and standards.
This practice has not necessarily been applied to non-pressure retaining components, as well as actuators, motor operators and associated air and control systems.
In the future, these items will be procured in accordance with original construction codes and standards.
~ s Action Item 2 "Include PORVs, valves in PORV control air systems, and block valves within the scope of a program covered by Subsection
- IWV,
'Inservice Testing of Valves in Nuclear Power Plants,'f Section XI of the ASME Boiler and Pressure Vessel Code.
Stroke testing of PORVs should only be performed during Mode 3
(HOT STANDBY) or Mode 4 (HOT SHUTDOWN) and in all cases prior to establishing conditions where the PORVs are used for low-temperature overpressure protection.
Stroke testing of the PORVs should not be performed during power operation.
Additionally, the PORV block valves should be included in the licensees'xpanded MOV test program discussed in NRC Generic Letter 89-10,
'Safety-Related Motor Operated Valve Testing and Surveillance,'ated June 28, 1989."
~Res ense The purpose of the IST Program is to provide indication of component reliability.
The PORVs and block valves are currently in the Cook Nuclear Plant second 10-year IST Program.
A separate test of the valves in the PORV control air system, however, is not presently included in the IST Program.
Given the existing configuration of the control air system, separate testing of its components within the IST Program would not be possible without significant system modifications and/or numerous exemptions.
Since current in-service testing of the PORVs already indirectly provides assurance of proper operation of the control air system, we do not intend to separately include the control air system components in the IST Program.
Indirect testing will continue to be accomplished by testing the
- PORVs, on a cold shutdown frequency as covered by the IST Program, in accordance with plant procedures.
This will include testing to ensure that the valves stroke using normal and backup air supplies.
ATTACHMENT TO AEP:NRC:1131 PAGE 4 Action Item 2 also states that the PORV block valves should be included in the MOV testing program discussed in NRC Generic Letter 89-10, "Safety-Related Motor-Operated Valve Testing and Surveillance."
These valves have been included in the MOV testing program.
Action Item 3 "For operating PWR plants, modify the limiting conditions of operation of PORVs and block valves in the technical specifications for Modes 1, 2, and 3 to incorporate the position adopted by the staff in recent guidance.
The staff recognizes that some recently licensed PWR plants already have technical specifications in accordance with the staff position.
Such plants are already in compliance with this position and need merely state that in their response, These recent technical specifications require that plants that run with the block valves closed (e.g.,
due to leaking PORVs) maintain electrical power to the block valves so they can be readily opened from the control room upon demand.
Additionally, plant operation in Modes 1, 2, and 3 with PORVs and block valves inoperable for reasons other than seat leakage is not permitted for periods of more than 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br />."
~Res ense The Cook Nuclear Plant Technical Specifications for Modes 1, 2, and 3 will be modified to agree with those proposed by the staff with one exception.
Given that we have three
- PORVs, we will propose that plant operation in Modes 1, 2, and 3 be permitted with one PORV or block valve inoperable for reasons other than excessive seat leakage.
Operation in these modes with more than one PORV or block valve inoperable for reasons other than seat leackage will not be permitted for periods of more than 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br />.
Our proposed Technical Specifications
- changes, and related justification, to address this issue will be submitted to you separately in early 1991.
Enclosure B - Section 3
Staff Positions Resultin from Resolution of Generic Issue 94 "Additional Low Tem erature Over ressure Protection for Li ht Water Reactors" Action Item The current 7-day AOT for a single channel is considered to be too long under certain conditions'he staff has concluded that the AOT for a single channel should be reduced to 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> when operating in MODE 5 or 6 when the potential for an overpressure transient is highest."
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ATTACHMENT TO AEP'NRC'1131 PAGE 5
R~es ense The Technical Specifications will be revised using the guidance in Attachment B-1 as it specifically applies to Cook Nuclear Plant.
Recognizing that we rely on PORVs and the RHR safety valve for low temperature overpressure protection (LTOP) and that the applicability of the LTOP system is limited to temperatures below 170 F for Unit 1 and 152 F for Unit 2, the 7-day AOT for Mode 4 () 200 F) is not applicable to Cook Nuclear Plant.
Proposed Technical Specifications changes will also be addressed as part of the aforementioned submittal to be made in early 1991.