ML20065S917
| ML20065S917 | |
| Person / Time | |
|---|---|
| Site: | Callaway  |
| Issue date: | 12/18/1990 |
| From: | Schnell D UNION ELECTRIC CO. |
| 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 GL-90-06, GL-90-6, ULNRC-2343, NUDOCS 9012260164 | |
| Download: ML20065S917 (8) | |
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1901 Ctwtenu Annue -
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December 18, 1990 p
U.S. Nuclear Regulatory Commission ATTN:
Document Control Desk Mail Station Pl-137 Washington, D.C.
20555 Genticmon:
ULNRC-2 34 3 CALLAWAY PLANT DOCKET NUMBER 50-483-GENERIC' LETTER 90-06 i=
On: June 25, 1990, the NRC issuod Generic-Lotter (GL) 90-06, " Resolution of-Generic Issue 70, ' Power-Operated Relief Valvo and Block Valve R211 ability', and Generic Issuc'94, ' Additional Low-Temperature overpressure Protection For Light Water Reactors', Pursuant-to 10 CFR 50.54=(f)".- The generic letter rcquired PWR:licenscos to
-advisc-the NRC' staff, under oath or_ affirmation _within 180 days of.the date of this lotter, of our current plans relating to pressurizer power operated relief valves (PORVs) and block valves and to: low-temperature overpressure protection.
Unio'n=Electricf.?ill follow the staff positions. presented:
in Enclosures A and B of the generic letter-as discussed-below._-Enclosure A of GL 90-06 requests-theLfollowing:
"1.
-Include PORVsfand block valves within the scopc-of an operational quality assurance' program that'is_in-compliance-with--10 CFR Part 50,.
3
' Appendix B.
This program should includo the follouing elements:
a.-
The addition of PORVs and block valves lto-the plant-operational Quality ~ Assurance List.
a b.
Implomontation of a.maintenanec/ refurbish-ment-program for:PORVs and block. valves
- that is based on the manufacturcr's recommendations or guidelines and is-implemented by trained plant maintenance.
personnel._
Oli 9012260164 901218
-PDR -ADOCK 05000483 A
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-P PDR 4 % s J a a.
c.
When replacement parts and spares, as well as complete components, are required for existing non-safety grado PORVs and block valvos (and associated control systems),
it is the intent of this goncric letter that these items may be procured in accordance with the original construction codes and standards".
At the Callaway Plant the PORVs and block valvos arc safety-related as described in sections 5.4 and 3,ll(B) of the Final Safety Analysis Report (FSAR).
This classification subjects the PORVs and block valves to the Callaway Quality Assurance Program.
They were designed in accordance with the A3ME code and are qualified via the Westinghouse pump and valve operability program which is described in Section 3.10(N) of the FSAR.
The maintenance / refurbishment program for the PORVs and block valves is based on the manufacturer's recommendations.
Replacement parts and spares are processed in accordance with the original construction codes and standards.
Itc.n 2 of Enclosure A requests that licenscos:
"2.
Include PORVs, valycs in PORV control air systems, and block valves within the scope of a program covered by Subsection IWV, 'Inservico Testing of Valves in Nuclear Power Plants,' of Section XI of the ASME Boiler and Pressure Vessel. Code.
Stroke testingaof the 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 overpressuro protection.
Stroke testing of the; PORVs should not be performed during power operation. -Additionally, the PORV block valves should be included in the licensees' expanded MOV test program discussed in NRC Generic Letter 89-10, ' Safety-Related Motor Operated Valvo Testing and Surveillances, dated June 28, 1989".
At Callaway, the PORVs are full stroke tested at a cold shutdown frequency in accordance with the Inservice Test Program (IST) and Callaway Technical Specifications 4.4.4.1, 4.4.4.2, 4.4.9.3.1, and 4.0.5.
Additionally, the PORV block valves are Page 2
stroke tested quarterly in accordance with the Technical Specifications and have been included in our expanded MOV test program as required by NRC GL 89-10, " Safety-Rolated Motor Operated Valvo Testing and Surveillance".
Item 3 of Enclosure A states:
"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 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 />."
Attachment A-1 proposes a technical specification for Combustion Engineering and Westinghouse Plants with two PORVs.
A request to ammond Callaway Technical Specification 3.4.4 will be submitted por Attachments A-1 and A-3 as follows:
1)
ACTION a will require that power be maintained to closed block valves; 2)
ACTIONS a, b, and c will be changed to terminate the forced shutdown requirements with the plant being in HOT SHUTDOWN rather than COLD SHUTDOWN because the APPLICABILITY requirements of the LCO do not extend past the HOT STANDBY mode; and, 3)
ACTION d will be modified to establish remedial measures that are consistent with the function of the block valves with the following exception Attachment ?-3 states that the OPERABILITY of the PORVs is based, in part, on their being able to automatically control reactor coolant system Page 3
LC.
pressure to reduce challenges to the safety valves.
However, Westinghouse standards'for transient and accident analyses state that control systems are not assumed to operato unless their operation will cause the results of-tho transient or accident analysis to be more severe.
In kooping with Westinghouse standards, the Callaway accident analyses do not rely on automatic actuation of the PORVs to provent overpressurization.
Thorofore, callaway Technical Specification 3/4.4.4, "Rolief Valves," is adequato to ensurc that the PORVs are available for manual operation for mitigation of a steam generator tube rupture accident and achieving plant cooldown in accordance with Branch Technical Position RSB 5-1 to Standard Review Plan Section 5.4.7.
The callaway Technical Specification surveillance requirements for the PORVs and block valvos do not need to be changed because:
1) the IST Program requires full stroke testing _of the PORVs at a cold shutdown frequency and full stroke testing of the block valves overy 3 months (The Callaway IST Program has been approved by NRC);
2) there cro no pncumatic components associated with the PORVs or block valves; and, 3) the callaway PORVs.and block valvon were originally designed as safety-related components.
Therefore, their normal power supplics arc from IE busses with no-cmergency power supply transfer required.
In Enclosurc B of GL 90-06, the Staff provides an extended discussion of positions resulting from the resolution of Generic Issue 94, " Additional Low-Temperature Overpressure Protection For Light-Water Reactors".
Low temperaturc overpressure protection is discussed in subsections 5.2.2.10 and 5.2.2.11 of_the PSAR.
At Callaway, the operability of two PORVs, or two RHR suction relief valves, or_a reactor coolant system vent opening of at least 2 square inches ensures that the RCS will be protected as required by.10CFR50, Appendix G.
Either PORV or cither RHR-suction relief valve has boon K
_chown by plant specific analysis to have adequate relieving capability to protect the RCS from overpressurization when the transient is limited to either:
Page 4
1)'
the start of an id3c reactor coolant pump (RCP) with the secondary water temperature of the steam generator less than or equal to 50*F above the RCS cold log temperatures, or 2)-
the start of a single centrifugal charging pump and its injection into a water-solid RCS.
In addition, callaway has deleted the Auto closure Interlock (ACI) Function as part of Callaway License Amendment 42.
The dolction of the ACI circuitry helps to insure the availability of the RHR suction relief valvos to provido cold overprossure protection.
Union Electric believes that the protection provided by the PORVs and/or RHR suction relief valves in addition to the limitations on safety injection pump operability, starting of RCPs and other administrativo controls arc adequato to meet the intent of GL 90-06 (i.e., to minimize the potential for cold overpressurization events).
-Union Electric is cooperating with six other utilitics in developing a common approach to GL 90-06, Enclosure B.
The plants involved in this effort are:
Wolf Crock, Vogtle, Comancho Peak, Millstonc 3, Scabrook, Byron, Braidwood, and Callaway.
A joint effort is possible due to the similarity of plant types and technical specifications.
All the plants arc Westinghouse PWRs which utilize the PORVs and RHRS suction relief valvos for low-temperature overpressure protection.
Cal away Plant Cold Overpressure Technical Specification 3.4.9.3 currently allows use of cither the PORVs or RHR suction relieve valves.
A sample specification for this configuration was not provided in the GL.
A revised Technical Specification which reflects this configuration will propose a 24-hour allowed outage time when only one means of cold overpressure protection is availabic.
The proposed Technical Specifications will require that at least two of these devices must~be. operable.
That is, 2 PORVs or 2 RHR Suction Relief Valves or 1 PORV and 1 RRR
~
Suction Relief Valve must be operabic when cold.
. overpressure protection is required.
For Callaway, the overpressure protection system is-((
required to be'operabic in Modo 3 below 368'F and in modos 4, 5 and 6.
An additional ACTION statement will be proposed to address Mode 3 (below 368'F) and Mode 4 when.
only one pressure relief device is operable.
This-is consistent with GL 90-06 Attachment B-1.
No changes to the surveillance requirement are required.
Page 5-
9 i
L Union Electric anticipatos that a revision to Callaway Technical Specifications 3/4.4.4, Relief Valves and 3.4.9.3, Overpressure Protection System will be submitted by the end of the first refucling outage that starts six months or later from the date of the Goncric Lotter (Spring, 1992).
j l-Very truly yours, Nt
SUBSCSIBED and swot. to before me this day of
- M */,'u 1990.
A4lLt4 h f)NX,/
0/umiuu\\.
t \\t P NOI31 PUtuiC, SI ATE OF M!5;0URI Mr COMM:S 'Orl IXNRES ArRR 22. 1993 ST. LOUIS COUNTY
1 e cci T. A.
Baxter, Esq.
Shaw, Pittman, Potts & Trowbridge 2300 N.
Street, N.W.
Washington, D.C.
20037 Dr.
J.
O.
Cermak CFA, Inc.
4 Professional Drive (Suite 110)
Gaithernburg, MD 20879 R.
C.
Knop Chief, Reactor Project Branch 1 U.S.
Nuclear Regulatory Commission Region III 799 Roosevelt Road Glen Ellyn, Illinois 60137 Bruce Bartlett Callaway Resident Office s
U.S.
Nuclear Regulatory Commission RR#1 Steedman, Missouri 65077 4
Anthony T.
Gody, Jr. (2)
Office of Nuc. lear Reactor Regulation U.S.
Nuclear Regulatory Commission 1 White Flint, North, Mail Stop 13E21 11555 Rockville Pike Rockville, MD 20852 Manager, Electric Department Missouri Public Service Commission P.O.
Box 360 Jefferson City, MO 65102
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