ML20065S800
| ML20065S800 | |
| Person / Time | |
|---|---|
| Site: | Wolf Creek  |
| Issue date: | 12/21/1990 |
| From: | Rhodes F WOLF CREEK NUCLEAR OPERATING CORP. |
| To: | 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 ET-90-0190, ET-90-190, GL-90-06, GL-90-6, NUDOCS 9012260069 | |
| Download: ML20065S800 (5) | |
Text
s.
l LF CREEK W8) NUCLEAR OPERATING 3
@,'N2nf December 21, 1990 ET 90-0190 U. S. Nuclear Regulatory Commission ATTH: Document Control Desk Mail Station Pl.137 Washington, D. C. 20555
Subject:
Docket No.
50-482:
Response to Generic Letter 90-06, j~
Resolution of Generic Issue 70,
" Power-Operated Relief I
Valve and Block Valve Reliability..' and Generic Issue 94,
' Additional Low-Temperature Overpressure Protection for Light-Water Reactors' Gentlemen The purpose of this-letter is to provide Wolf Creek Nuclear Operating Corporation's (WCNOC) response to Generic Letter 90-06, Resolution of Generic Issue.70, ' Power-Operated Relief Valve and Block Valve Reliability,'
and Generic Issue 94,
' Additional Low-Temperature Overpressure Protection for Light-Water Reactors".-
The Nuclear Regulatory Conunission (NRC) issued Generic Letter 90-06 to advise pressurized water reactor licensees of the staff'e position resulting from the resolution of Generic Issues (GI)70 and 94.
On the basis of technical studies for'GI 70 and 94,
~ he staff has t
requested that to enhance safety, the actions in the Generic Letter be-taken by licensees that use or could use power-operated relief valves (PORVs) to.
perform safety-related functions.
The Attachment provides WCNOC's plans relatiPd to the NRC requested actions concerning PORVs and block valves-and t r.
low-temperature-overpresi;f re protection.
4 If you have any questions concern 4 g this matter, please contact me or Mr. H. K. Chernoff of my staff.
Very truly yours, 1-Forrest T. Rhodes h0k kboh bbbbbkS2 Vice President p
PDR Engineering & Technical Services FTR/jra Attachment ecs
.A. T. Howell (NRC), w/a
'R D. Martin (NRC), w/a D. V. Pickett (NRC), w/a M. E. Skow (NRC), w/a P.O. Box 411/ Durtington, KS 66839 / Phone: (316) 3668831.
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O An Equal oppo*turuty Empsoyer M F+CVET
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STATE OF KANSAS
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) SS COUNTY OF COFFEY
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Forrest T. Rhodes, of lawful age, being first duly sworn upon oath says that he is Vice President Eagineering and Technical Services of Wolf Creek Nuclear Operating Corporatians that he has read the foregoing document and knows the content thereof:
that he has executed that same for and on behalf of said Corporation with full power and authority to do son and that the facts therein stated are true and correct to the best of his knowledge, information and belief.
M 57 Forrest T. Rhodes Vice President Engineering & Technical Services i
SUB ICRIBED and sworn to before me this $2 /
day of b = W 1990.
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Attachment to ET 90 0190 Page: 1:of-3-
RESPONSE TO GENERIC LETTER 90-06 REQUESTED ACTION:
1.
Include PORVs and block valves within the scope of an operational quality assurance program that is in compliance with 10 CFR Part 50, -
t Appendix B.
This Program should include the following elements:-
l a.
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.
RESPONSE
1.a.
The PORVs and block valves are safety-relat'ed as described in Sections 3.11(B)--and 5.4 of the Updated _ Safety Analysis Report and are included' on _the Wolf Creek Generating Station (WCGS) Q-list.
.The WCGS Q-list
_ provides a listing of-safety-related components.
1.b.
Preventative maintenance on the PORVs and block valves is based on the
-i manufacturer's recommendations and scheduled by the WCGS preventative maintenance program.
1.c.
Since the PORVs'and block valves are safety-related, replacement parts =
and spares are procured to _the appropriate technical and ~ quality _
requirements for-the procurement of safety-related items in accordance with procedure KGP-1250, " Requisition & Procurement-. Process".
REQUESTED ACTION:
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," of 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 perfcrmed during power operation.
Additionally, the PORY ' block valves should be included in the licensee's expanded MOV test program discussed in NRC Generic Letter 89-10,
" Safety-Related Motor Operated Valve Testing and Surveillance," dated June 28, 1989.
.. = -..
. -. =. -
s Attachment to ET 90-0190 Page 2 of 3 l
L l
RESPONSE
l The PORVs and block valves are included in the NRC approved WCGS Inservice Testing (IST) program.
The PORVs are full stroke tested on a cold shutdown frequency with the block valve open in accordance with the IST program and WCGS Technical Specifications.
The PORV block valves are stroke tested quarterly in accordance with Technical Specification Surveillance Requirement 4.4.4.1.
Aiditionally, the PORV block valves are contait.*d in the Generic Letter 89-10 Motor Operated Valve Test Program.
The t9st j
program for these valves is administered by procedure ADM 08-227, "Limitorque Valve Program".
REQUESTED ACTION:
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 licensing actions.
Attachments A-1 through A-3 are provided for 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 I
and need merely state that in their response.
These recent technical I
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 l
and block valves inoperable for reasons other than seat leakage is not t
l permitted for periods of more the 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br />.
l Revise current technical specifications for overpressure protection to reduce the allowable outage time for a single channel from 7 days to 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> when the plant is operating in Modes 5 or 6 (see Attachment B-1 to the Generic Letter).
RESPONSE
WCNOC participated with six other utilities to develop a common approach to Generic Letter 90-06.
The plants involved in this effort are:
- Callaway, Vogtle, Commanche Peak, Millstone 3. Seabrook,
- Byron, Braidwood, and Wolf Creek.
This group was formed due to the lack of specific guidance and a sample technical specification for the use of either the PORVs or the residual heat removal (RHR) suction relief valves.
A joint effort is possible due to the similarity of plant types and technical specifications.
l All the plants are Westinghouse pressurized water reactors which utilize the PORVs and RHR suction relief valves for low-temperature overpressure protection.
I Attachment A-1 to the generic letter proposes modified standard technical specifications for Combustion Engineering and Westinghouse plants with two PORVs. Wolf Creek Nuclear Operating Corporation (WCNOC) intends to submit a license amendment request to Technical Specification 3/4.4.4 which follows the staff positions with plant specific alternatives.
~
Attachment to E? 90-0190 Page 3 of 3 Enclosure B of the generic let*er was reviewed by the group and a proposed technical specification deve*4; ped that reflects the use of either the PORVs or the RHR suction relief vaives.
The proposed technical specification will require that at least two overpressure protection devices must_be operable.
That is, 2 PORVs or 2 RHR suction relief valves or 1 PORV and 1 RHR suction relief valve must be operable when cold overpressure protection is required.
Additionally, the revised specification will adopt a 24 hour2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> allowed outage time when only one overpressure protection device is available in Mode 5 or 6.
WCNOC intends to submit a license amendment request to Technical Specification 3/4.4.4, Relief Valves and 3.4.9.3, Overpressure Protection System, to reflect the above configuration by the end of the fifth refueling outage which is currently scheduled to start in September 1991.
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