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{{Adams
#REDIRECT [[ET 08-0011, Revisions to Proposed Changes to Technical Specification 3.7.3, Main Feedwater Isolation Valves (Mfivs)]]
| number = ML080640632
| issue date = 02/26/2008
| title = Wolf Creek - Revisions to Proposed Changes to Technical Specification 3.7.3, Main Feedwater Isolation Valves (Mfivs)
| author name = Garrett T J
| author affiliation = Wolf Creek Nuclear Operating Corp
| addressee name =
| addressee affiliation = NRC/Document Control Desk, NRC/NRR
| docket = 05000482
| license number =
| contact person =
| case reference number = ET 08-0011
| document type = Letter
| page count = 12
}}
 
=Text=
{{#Wiki_filter:W0LF CREEK NUCLEAR OPERATING CORPORATION Terry J. Garrett February 26, 2008 Vice President, Engineering ET 08-0011 U. S. Nuclear Regulatory Commission ATTN: Document Control Desk Washington, DC 20555
 
==Reference:==
 
Letter ET 07-0004, dated March 14, 2007, from T. J. Garrett, WCNOC, to USNRC
 
==Subject:==
Docket No. 50-482: Revisions to Proposed Changes to Technical Specification 3.7.3, "Main Feedwater Isolation Valves (MFIVs)" Gentlemen:
The Reference provided a license amendment request that proposed revisions to Technical Specification (TS) 3.3.2, "Engineered Safety Feature Actuation System (ESFAS)Instrumentation," TS 3.7.2, "Main Steam Isolation Valves (MSIVs)," and .TS 3.7.3, "Main Feedwater Isolation Valves (MFIVs)," based on a planned modification to replace the MSIVs and associated actuators, MFIVs and associated actuators, and replacement of the Main Steam and Feedwater Isolation System (MSFIS) controls.
The Reference included changes to TS 3.7.3 to incorporate into the technical specifications, requirements associated-to .the Main Feedwater Regulation Valves (MFRVs) and MFRV bypass valves. The MFRVs and MFRV bypass valves are added to TS 3.7.3 as these valves are credited in the accident analyses to provide a backup to the MFIVs for a potential failure of an MFIV to close.Wolf Creek Nuclear Operating Corporation (WCNOC) personnel recently identified that the changes proposed in the Reference to the Applicability in TS 3.7.3 did not accurately reflect the design conditions when the Limiting Condition for Operation (LCO) should be applicable.
Attachment I provides information regarding the additional changes to TS 3.7.3 LCO and Applicability.
Attachment II provides revised markups of affected TS 3.7.3 pages. Attachment III provides revised markups of affected TS 3.7.3 Bases pages. Themarked-up TS Bases pages are provided for information only.The revisions to the proposed changes to TS 3.7.3 and, information provided in the Attachments do not impact the conclusions of the No, Significant Hazards Consideration provided in Reference
: 1. In accordance with 10 CFR 50.91, a-copy of this submittal is being provided to the designated Kansas State official.P.O. Box 411 / Burlington, KS 66839 / Phone: (620) 364-8831 An Equal Opportunity Employer M/F/HC/VET tAQ ET 08-0011 Page 2 of 3 This letter contains no commitments.
If you have any questions concerning this matter, please contact me at (620) 364-4084, or Mr. Richard Flannigan at (620) 364-4117.Sincerely, Terry J. Garrett TJG/rlt Attachment II IIl Additional Changes to TS 3.7.3 Revised Markups of TS 3.7.3 Revised TS Bases Markups (for information only)cc: E. E. Collins (NRC), w/a T. A. Conley (KDHE), w/a J. N. Donohew (NRC), w/a V. G. Gaddy (NRC), w/a B. K. Singal (NRC), w/a Senior Resident Inspector (NRC), w/a ET 08-0011 Page 3 of 3 STATE OF KANSAS COUNTY OF COFFEY))Terry J. Garrett, of lawful age, being first duly sworn upon oath says that he is Vice President Engineering of Wolf Creek Nuclear Operating Corporation; that he has read the foregoing document and knows the contents thereof; that he has executed the same for and on behalf of said Corporation with full power and authority to do so; and that the facts therein stated are true and correct to the best of his knowledge, information and belief.TerryJ eesarrett Vice Piesident Engineering SUBSCRIBED and sworn rl GAYLE SHEPH Notary Public -State c My Appt. Expires /to before me this2LpLday of tJo. , 2008.EARD Notar ublic f Kansas Expiration Date _______2__
Attachment I to ET 08-0011 Page 1 of 3 Additional Changes to TS 3.7.3 Wolf Creek Nuclear Operation Corporation (WCNOC) letter ET 07-0004, dated March 14, 2007, provided a license amendment request that proposed revisions to Technical Specification (TS)3.3.2, "Engineered Safety Feature Actuation System (ESFAS) Instrumentation," TS 3.7.2, "Main Steam Isolation Valves (MSIVs)," and TS 3.7.3, "Main Feedwater Isolation Valves (MFIVs)," based on a planned modification to replace the MSIVs and associated actuators, MFIVs and associated actuators, and replacement of the Main Steam and Feedwater Isolation System (MSFIS) controls.WCNOC proposed changes to TS 3.7.3 to incorporate into the technical specifications, requirements associated to the Main Feedwater Regulation Valves (MFRVs) and MFRV bypass valves. The MFRVs and MFRV bypass valves are added to TS 3.7.3 as these valves are credited in the accident analyses to provide a backup to the MFIVs for a potential failure of an MFIV to close. This change included revising the Limiting Condition for Operation (LCO) and Applicability to address the addition of the MFRVs and MFRV baypass valves and the valve specific configurations.
Specifically, WCNOC proposed the following wording for the Applicability:
LCO 3.7.3 Four MFIVs and their associated actuator trains, four MFRVs and MFRV bypass valves shall be OPERABLE.APPLICABILITY:
MODE 1 MODES 2 and 3, except when: a. MFIV is closed and de-activated; or b. MFRV is closed and de-activated or closed and isolated by a closed manual valve; or c. MFRV bypass valve is closed and de-activated, or closed and isolated by a closed manual valve, or isolated by two closed manual valves.WCNOC personnel recently identified that the changes proposed in letter ET 07-0004 to the Limiting Condition for Operation (LCO) and Applicability in TS 3.7.3 did not accurately reflect the design conditions when the LCO should be applicable.
Specifically, it was determined that the proposed wording could allow the valves on different feedwater lines to be closed and result in the potential to not properly isolate the feedwater line. Additionally, the proposed wording would not result in isolation of feedwater flow if only the MFRV (and associated manual valve) is closed or the MFRV bypass valve (and associated manual valves) is closed. Both the MFRV and MFRV bypass valve in the same feedwater line must be closed to provide isolation of feedwater flow to the steam generator.
Attachment I to ET 08-0011 Page 2 of 3 Based upon the above, WCNOC is proposing to revise the LCO and Applicability as follows: LCO 3.7.3 Each MFIV and its associated actuator trains, MFRV and MFRV bypass valve for the four main feedwater lines shall be OPERABLE.APPLICABILITY:
MODE 1 MODES 2 and 3, except for each affected main feedwater line when: a. The MFIV is closed and deactivated; or b. The MFRV is closed and deactivated or closed and isolated by a closed manual valve; and the MFRV bypass valve is either closed and deactivated, closed and isolated by a closed manual valve, or isolated by two closed manual valves.The proposed revision of the LCO and Applicability are revised to reflect the appropriate design conditions for when the LCO should be applicable.
Attachment II provides revised markups of affected TS 3.7.3 pages. Specifically, pages 2 and 3 of Attachment II to this letter replaces page 9 of 12 of Attachment II to letter ET 07-0004. Attachment III provides revised markups of affected TS 3.7.3 Bases pages. Specifically, pages 2 and 3 of Attachment III to this letter replace page 37 of 46 and page 38 of 46 of Attachment IV to letter ET 07-0004. The proposed changes to TS 3.7.3 do not affect the changes provided in letter ET 07-0052, dated 12/18/07, to footnote (j) of TS Table 3.3.2-1.Use of Manual Isolation Valves Letter ET 07-0004 proposed changes to the TSs that would allow the use of manual isolation valves. Provided below is information regarding the manual valves specified in the proposed TSs.Valves AEV0076, 0078, 0080, and 0082 -are the manual isolation valves associated with the MFRV (see attached P&ID). These valves are 14 inch Crane gate valves. The valves are carbon steel with a pressure rating of 900 lbs.Valves AEV0257, 0258, 0259, 0260, 0261, 0262, 0263, and 0264 -are the manual isolation valves associated with the MFRV bypass valves. These valves are 6 inch Crane gate valves.The valves are carbon steel with a pressure rating of 900 lbs.These valves were purchased under Specification No. 16577-M-245, "Technical Specification for 600- Through 1500-pound Critical Check, Gate and Globe Valves 2-1/2 inches and LARGER-Carbon Steel to ANSI B31.1 for the Wolf Creek Generating Station," which provided design requirements that the valves and their actuator have a design life of 40 years at the specified environmental and service conditions.
The environmental conditions are that the valves are exposed to ambient conditions of 1) temperature of 600 to 120 0 F, 2) atmospheric pressure, and 3) 100% relative humidity.
The design service conditions are that the contained fluid be steam and feedwater.
Manual gate valves are typically used for system isolation when automatic isolation is not required.
Attachment I to ET 08-0011 Page 3 of 3 The use of a closed manual isolation valve is consistent with the Improved Standard Technical Specification (ISTS) 3.7.3 and Table 3.3.2-1. The TS 3.7.3 Bases, Applicability, states, in part: 'When the valves are closed and de-activated or isolated by a closed manual valve, they are already performing their safety function."
Attachment 11 to ET 08-001 1 Page 1 of 3 Revised Markups of TS 3.7.3 Attachment II to ET 08-00111 Page 2 of 3 3.7.3 3.7 PLANT SYSTEMS .r-szv "ByV ,-SS V'%\I ,s4 3.7.3 Main Feedwater Isolation Valves (MFIVs)LCO 3.7.3 APPLICABILITY:
Fo MFI'y,%nd t ir ass~oratedA'ctua~rtrýi41s sh~alf be/,1ýRABWk.
ACTIONS CONDITION REQUIRED ACTION COMPLETION TIME A. One MFIV actuator train A.1 Restore MFIV actuator 7 days inoperable, train to OPERABLE status.B. Two MFIV actuator trains B.1 Restore one MFIV 72 hours inoperable for different actuator train to MFIVs when the inoperable OPERABLE status.actuator trains are not in the same separation group.C. Two MFIV actuator trains C.1 Restore one MFIV 24 hours inoperable when the actuator train to inoperable actuator trains OPERABLE status.are in the same separation group.D. Two actuator trains for one D.1 Declare the affected MFIV Immediately MFIV inoperable.
inoperable.(continued)
.1 Wolf Creek -Unit 1 3.7-8 Amendment No. 12-3, 171 Attachment II to ET 08-0011 Page 3 of 3 INSERT 3.7-8A Each MFIV and its associated actuator trains, MFRV and MFRV bypass valve for the four main feedwater lines shall be OPERABLE.INSERT 3.7-8B MODE 1 MODES 2 and 3, except for each affected main feedwater line when: a. The MFIV is closed and deactivated; or b. The MFRV is closed and deactivated or closed and isolated by a closed manual valve; and the MFRV bypass valve is either closed and deactivated, closed and isolated by a closed manual valve, or isolated by two closed manual valves.
Attachment III to ET 08-0011 Page 1 of 3 Revised TS Bases Changes (for information only)
Attachment III to ET 08-0011 Page 2 of 3 Ca~yv MFR\s MrIA tiFi'v 13R-vsVai MFIVs B3.7.3 (ine& &55ock'akeýA O.cLAaMof
-+ratn, ' WAI BASES LCO eachc- MF=V a.nA its a&scri&?reA a LtA&tor -rq i mc5- MFg.V o~v~cvL MFR.V byp~se. VAlve 16- t~eA:UX'OPER^15LE
.I This LCO ensures that the MFIVsY ilsolate MFW flow to the steam generators, following an FWLB or main steam line break. .xaW'-will also isolate the nonsafety related portions from the safety related portions of the system. A--. " zia e.This LCO requires that o MF ls and lHeir ap-gociat actu For trai-. be COP AE. T,46 MFI s are ,onid ie RAB wh isola' n kiittes ae witbn limi and they on isola 'on acu'ation srgnal."'-An MFIV actuator train is considered OPERABLE when it is capable of (j)closing the associated MFIV on demand and within the required isolation time. "hjs'includps havingadequAte ac mu latoepressye to'sup-jl6rt fst-cloq6 re of tJe MF IVithin req isopion tip re andy Failure to meet the LCO requirements can result in additional mass and energy being released to containment following an SLB or FWLB inside containment.
A feedwater isolation signal on high steam generator level is relied on to terminate an excess feedwater flow event, and failure to meet the LCO may result in the introduction of water into the main steam lines.APPLICABILITY The MFIVsmust be OPERABLE whenever there is significant mass and energy in the Reactor Coolant System and steam generators.
In , tr.V 5 KVS .- VV MODES 1, 2, and 3, the MFIV .are required to be OPERABLE to perform 6o..,5 yA1.e-., their isolation function and limit the amount of available fluid that could be 9 9 ýý;6 ýadded to containment in the case of a secondary system pipe break inside containment.
When the valves are closed, they are already performing their safety function.
The MFIV actuator trains must be OPERABLE in MODES 1, 2, and 3 to support operation of the MFIV.In MODES 4, 5, and 6, steam generator energy is low. Therefore, the MFIVscan be closed since MFW is not required.ACTIONS The LCO specifies OPERABILITY requirements for the MFIVs as well as for their associated actuator train The Conditions and Required Actions for TS 3.7.3 separately address inoperability of the MFIV actuator trains for and inoperability of the MFIVs themselves.
Wolf Creek -Unit 1 B 3.7.3-3 Revision 130 Attachment III to ET 08-0011 Page 3 of 3 INSERT B 3.7.3-3a The MFIVs are considered OPERABLE when isolation times are within the limits of Figure B 3.7.3-1 when given a close signal and they are capable of closing on an isolation actuation signal. The MFRVs and MFRV bypass valves are considered OPERABLE when isolation times are < 15 seconds when given an isolation actuation signal and they are capable of closing on an isolation actuation signal. For the MFRVs and the MFRV bypass valves, the LCO requires only that the trip close function is OPERABLE.INSERT B 3.7.3-3b Feedwater is supplied to the four steam generators by four feedwater lines. One MFIV is installed in each of the four feedwater lines downstream of the MFRV and MFRV bypass valve.When the feedwater line that feeds the steam generator is isolated, the safety function is being met. In MODES 2 and 3, a MFIV, MFRV and MFRV bypass valve on their associated main feedwater line are not required to meet the requirement of this LCO where the valve(s) are assured of performing their safety function as follows: a. When the MFIV is closed and de-activated, it is performing is safety function.
Requiring the valve closed and de-activated provides assurance that it is performing its safety function.
The MFIV is a system-medium actuated valve, opened by system pressure acting on the lower piston chamber, closed by the weight of the valve internals and system pressure acting on the upper piston chamber. To de-activate the MFIV, the electrical power sources are removed from the actuation solenoids and a drain or vent path is available from the lower piston chamber.b. Isolation of the feedwater line is accomplished by isolation of the MFRV and MFRV bypass valve. When the MFRV is closed and de-activated or is closed and isolated by a closed manual valve, it is performing its safety function.
Requiring the valve closed and de-activated provides dual assurance that it is performing its safety function.
When the valve is de-activated, power is removed from the actuation solenoids on the valves.Requiring the valve closed and isolated by a closed manual valve also provides dual assurance that it is performing its safety function.
When the MFRV bypass valve is closed and de-activated, or is closed and isolated by a closed manual valve, or is isolated by two closed manual valves, it is performing its safety function.
Requiring the valve closed and de-activated provides dual assurance that it is performing its safety function.
When the valve is de-activated, power is removed from the actuation solenoids on the valves. Requiring the valve closed and isolated by a closed manual valve also provides dual assurance that it is performing its safety function.
Finally, there is assurance that the safety function is being performed when the MFRV bypass valve is isolated by two closed manual valves.}}

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