2CAN129013, Responds to Generic Ltr 90-06 Re Resolution of Generic Issue 70, Power-Operated Relief Valve & Block Valve Reliability & Generic Issue 94, Addl Low-Temp Overpressure Protection for Lwrs
| ML20066A267 | |
| Person / Time | |
|---|---|
| Site: | Arkansas Nuclear  |
| Issue date: | 12/21/1990 |
| From: | James Fisicaro ENTERGY OPERATIONS, INC. |
| To: | NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM) |
| References | |
| REF-GTECI-070, REF-GTECI-094, REF-GTECI-NI, TASK-070, TASK-094, TASK-OR 2CAN129013, GL-90-06, NUDOCS 9101030126 | |
| Download: ML20066A267 (10) | |
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Operations December 21, 1990 2CAN129013 U. S. Nucionr Regulatory Commission Docnment Control Desk Hail Station P1-137
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Washington, D. C.
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Subject:
Arkansas Nucicar One-Unit 2 J
Docket t'a. 50-368 1,1conse No. NPI-6 Response to tieneric Let ter 90-06 Gentlemen:
Generic Lnt'.cr 90-06, Resolution of Gnneric Issue 70, " Power-Operated Rollof Valvo and Block Valvo Rnifability," and Generic issuo 94, " Additional I,ow-Temperaturn Overpressure Protection for hight-Water Reactors" was issued on Juno 25, 1990 (0CNA069027) to advise licensees of the NRC St af f positions with rnspect. to resolution of theso Generic Is<iuen.
The Sta f f posit ions are delinnat.ed in Enclosures A and B to thn Generic Letter.
With respect to the Staf f positions delineated Jn Enclosure A, Entergy Operationn, Inc. commits to implement the intent of the improvements Jdentifled in Section 3 of Enclosure A.
Since the design of Arkansas Nuclear One-Unit 2 does not ut (lino power-oporated r el tof valves for low-temperaturn overpressure protection, the specific actions of Enclosure A cannot be totally implemented.
However, a majority of the improvement actions identified in the Staf f positions hnvn already been implemented at Arkansas Nuc1 car One-Unit. 2 for the installed low-temperaturn ovorpressure protection system components.
As sach, the Intent of the improvement actions has bonn satisfied with the-exception of Technical Spec 1fication requirements.
Information regarding the unique design configuration and current status of Arkansas Nuclear One-Unit 2 with respect to the Stof f positions are provided in the enclosed Attachment. to this letter.
Entergy Operations, Inc. will proposo Technical Specification changes for Arkansas Nuclear Ono-Unit 2 t:at provido limiting conditions for operation in Hodos 4, 5 and 6 for the low-t empernt.ure overpressure protnct ion r,ystem based en the guidanco provided in Attachment B-1 of Enclosure B.
As discussed above, the proposed Technical Specification changes can only utilize the guidanco ptovided in Enclosure B since Arkansas Nuclear One-Unit. 2 has a unique design for low-temperaturn overpressure protection.
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U. S. NRC December 21, 1990 j
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Entergy Operations, Inc. will also propose Technical Speciffention changes for Arkansas Nuclear Onn-Unit. 2 that consider block valvo operability in Moden 1 2 and 3 for the low-temperaturn overpressure protection system.
Since the design of Arkansas Nuclonr One-Unit 2 for low-temperature overpressurn prot ection is uniquo when compared to other Combustion Enginocring designed plants, thn Technical Spectfication changes provided in Attachmnnt A-1 of Enclosure A are not directly applicable.
I Generic Letter 90-06 requests that the proposed Technical Specification changes be submitted prior to startup from the first refueling outage that occurs six mont hs af ter thn dato of the Generic hetter.
Entergy Operations, Inc. proposes an altornate schedulo due to the near term constraint on i
Arkansas Nucinar One Unit 2 outngo resources (outagn to begin in February 1991) and to utilize consistent timing on submittal of Technical Specification changes for revised prostiurn-temporaturn operating limits.
Submittal of Technical Specification changes for the low temperature overpressure protection system componnnts will coincide with a currently plannnd submittal of Technical Specification changes to modify the pressure-temperaturn operating limits for Arkansas Nucient One-Unit 2.
This submittal schedule has been selected since the revised pressurn-temperature opernting limits may modify the low-temperature overpressure protection setpoints part, way into Cycle 9 operation. The proposed schedulo for submittal of these Technical Specificat.iori changes is June 1, 1991.
This Information 18 being provided under affirmnLion pursuant to 10 CPR 50.54(f).
please advlan if you requirn any additional information.
Very truly yours, us,Ut-A c- - -,
James J$ Fin (caro Manngor, Licensing JJF/SAB/sgw Attachment c
U. S. NRC Der, ember 21, 1990
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cet Mr. Robert Hartin U. S. Nucinar Regulatory Cornmission Region IV 611 Ryan Plaza Drive, Suite 1000 Arlington, TX 76011 1,oman W. Alexion NRR Project Manager, Region IV/ANO-1 U. S. Nuclear Regulatory Comniission NRR Mail Stop 11-B-19 One White Flint North 11555 Rockville Piko
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Rockville, Maryinnd 20852 NRC Senior Resident Inspector Arkansas Nuclear One - ANO-1 & 2 Number 1, Nucicar Plant Road Russellville, AR 72801 Hn. Sherl Potorson NRR Project Manager, Region IV/ANO-2 U. S. Nucionr Regulatory Commission NRR Hall Stop 11, 19 Ono Whito Flint North 11555 Rockville Piko Rockv1110, Marylard 20852 I
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STATE OF ARKANSAS
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SS COUNTY OF !.00AN
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- 1. J. J. Fiscaro, being duly sworn, subscribe to and say that I am Manager, Licensing ANO for Entergy Operations, Inc.; that I have full authority to execute this onth; that I have rend the document numbered 2CAN129013 and know the contents thereof; and that to the best of my knowledge, information and bollef, the statements in it. are trun.
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Q.J.Fidiento SUllSCR111ED AND SWORN To before mn, a Notary Public in and for thn County and Stato above named, this 2/Jd day of 3d81/6 1990.
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Attachment to 2CAN129013 Pagn 1 a
Arkans.ns Nucl. ear _One: Unit _2 Low-Temperaturo overpressure Protection Designs.
The design of the LTOP system at Arkansas Nuclear One-Unit 2 (ANO-2) is unique when compared to othnr Combustion Engineering designed plants since the design does not employ power-operated relief valves on the pressuriznr or rollef valves on the shutdown cooling system to provide low-temperaturn overpressure I
protection of the reactor vessel. As described in Sections 5.2.2.4, 5.5.13, 7.6.1.3 and 7.6.2.3 of the ANO-2 Safety Analysis Report (SAR), overpressure protection of the reactor coolant system (RCS) during low temperature operation is provided by two redundant Low-Temperature Overpressure protection (LTOP) relief valves through a single dischargo hondor.
Each relief valve has the capacity to accommodate a worst case full safety injection initiation from a water solid RCS condition.
Each LTOP relief valve is mounted to the top of the RCS pressurizer through two isolation (or block) valves and connecting piping.
Tha LTOP relief valves are operator enabled (by opening the block valves) during cooldown when the RCS corresponds to the temperature conditions wh,to LTOP is required, and isolated from the RCS during heatup when the RCS is above the LTOP temperature conditians.
An alarm circuit is provided to alert thn operator if the RCS temperature drops to the LTOP temperature condition and any block valvo fs not fully open.
The design only requires that thn operator line up the relief vnives during cooldown and isolats during heatup. No other operator action is reqcited to prevent. an overpressurization event at low temperature.
S AFETY_FUNCTI 0.NS_OF_PORVe_A_ND_B LOCK _V ALVESjGL 90__06xEn c 1 o a u r o A., S oc t i on 2)2 Generic Let ter 90-06 Enclosurn A, Section 2 states that over a period of time the role of PORVs has changed such that PORVs are now rolled upon by many plants t.o perform one, or more, of tho following sa fet y-related funct ions :
1.
Mitigation of a design-basin steam generator tube rupture accident, 2.
Low-temperature overpressure protection of the reactor vessel during startup and shutdown, or 3.
Plant cooldown in complianen with Branch Technical Position kSB 5-1 to SRP 5.4.7, " Residual Heat. Removal (RHR) System."
Section 2 fat ther states that where PORVs are used or could be used to perform one, or more., of these safety-related functions or to perform any other safety-related function in the future, it is appropriato to reconsider the i
safety classification of PORVs and the associated block valves,
Attachment to 2CAN129013
' Page 2 Arkansas Nucicar_One-ynit 1 _ Response:
As describnd above, the uniquo design of the LTOP system for ANO-2 employs relief valves and block valves ircunted to the top of the RCS pressurizer.
As such, the design does not rely upon power-operated reller valves to perform any of the safety-related functions identified in Section 2 of Enclosure A.
Ilowever, the LTOP system components are rolled upon to provido low-temperature overpressure protection of the reactor vessel during startup nnd shutdown.
The block valves also function as passive reactor coolant pressure boundary integrity volves during operation in Modes 1, 2 and 3.
The following provides a descriptfon of the ANO-2 design with respect to reliance upon LTOP system components for each safety-related function:
1.
tiltigation of a desjgn-t> asis steam generator tubn rupture accident.
Section 15.1.18 of the ANO-2 SAR describes the analysis and the results for the Steam Generator Tubo Rupture accident.
Since the design of the LTOP system for ANO-2 does not incorporate PORVs, the LTOP system components are not relind upon to perform this safety-related function.
2.
Low-temperaturn overpressure protection of the reactor vessel during startup and shutdown.
As described above, the ANO-2 design of the LTOP system includes relief valves and associated block valves which are relied upon to perform this safety-related function.
3.
Plant cooldown in compliance with Branch Technical Position RSD 5-1 to SRP 5.4.7, " Residual llent Removal (PilR) System."
ANO-2 was licensed prior to issuance of the Standard Review Plan and Branch Technical Position RSB 5-1.
Thereforo, the licensing basis for ANO-2 does not require complianen with Branch Technical Position RSB 5-1 to SRP 5.4.7, " Design Requirement s of the Residual linat Removal (RilR) System."
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Attachaent to 2CAN129013
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. IMPROVEMENTS TO ALL_PORVs AND B. LOCK _VALVESJ GL_90._0_6; Enclosuro A, Section 3)J Generic Lotter 90-06 Enclosure A, Section 3 provides the Nr0 Staf f pos1Llon with respect to actions which should be taken by licensees improve the rollability of PORVs and block valves.
Even though the LTOP system does not incorporate PORVs, Information regarding the LTOP relief valves and associated block valves for ANO-2 are provided below to address the three separate actions presented in Section 3.
NRC Staff Position 3.1, Item 1:
Include PORVs and block valves within the scope of an operational quality assurance program that is in compliance wit.h 10 CFR Part 50, Appendix B.
This program should include the following elements:
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- a. The addition of PORVs and block velves to the plant operational Quality Assuranco List.
b Implomontation of a maintenance / refurbishment program for PORVs and block valver 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 s tandards.
Arkansas Nuclear _One-Unit 2 Response:
The AND-2 LTOP rollef valves and associeted block valves a a within the scope of the Arkansas Nuclear one Quality Assuranco Manual Oper'.tlons (QAMO).
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QAMO monts the requirements of 10 CFR Part 50, Appendly a.
Component Level Q-List phich is maintained current in t', Station Information Management System (SIMS) Component Data Base.
The relief valves are -classified as QA Category S, Safety Class 2 components (non-Q, non-Fire protection equipment / components subject to the QA Program requirements of 10CFR50 Appendix B as imposed by the NRC and/or committed l
to by Entergy Operations, Inc.) with a Q-Function of T1 (docketed NRC l
correspondence, commitments including SAR).
The rollof valves worn originally procured (valve manufacturer was the J. E. Lot.crgan Company) as Seismic Class I, ASME Section III, Class II valves.
The LTop block valves (2CV-4730-1, 2CV-4731-2, 2CV-4740-2 and 2CV-4741-1)
-are also included in the ANO-2 Component Lovel Q-List in the SIMS Component Dnta Base.
These valves arn classified as QA Category Q, Safety Class 1 components with a Q-Function of C4 (RCS Pressure Boundary Integrity; Passive).
The valvo manufacturer (Borg-Warner Corporation) is on the ANO QVL and has an approved ASME Section III NCA QA program.
Attachment to 2CAN129013
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- b. Hafntenai.ce t.r.
? pair activities which affect quality and safety-at Arkansas Nuc.lc no are implemented through controlled procedures by trained plant personnel an described in the QAMO.
Each proceduto is suf ficiently detalled such that a qualified individual may perform the rnquired functions without direct supervision.
Maintenance or refurbishment of the LTOP relief valves is controlled through Hechanical Maintenance Procedure No. 2402.08T which was prepared using the manufacturer's technical manual. Maintenance or refurbishment of the associated block valves is controlled through the issuance of specific Work I'lans in accordance with Administrative Procedure No. 1000.006.
W( -k Plans r.cet the review and approval requirements of existing procedures.
- c. Repiocament. parts and spares, as well as complete components for tao Lf0P Relief valves and block valves (and associated control systems) are procured in accordance with the applicable codes and standards as required by the QAMO.
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Attachment to 2CAN129013
' Pago 5' NRC Staff Position 3.1; Item 2:
Include PORVs, valves in PORY control air systems, and block valves within the scope of a program covered by.9ubsection IWV, "Inservico Testing of Valves in Nuc1 car Power Plants," of Section XI of the ASME Boller and Pressure Vessel Code.
Stroke testing of PORVs should only be performed during Mode 3 (il0T STANDBY) or Mode 4 (liOT SHUTDOWN) and in all cases prior to establishing conditions where the PORVs are used for low-temperature overpressure protection.
Stroke test.ing of the PORVs should not be performed during power operation.
Additionally, the PORV block valves should be included in the licensons' expanded MOV test 1ogram discussed in NRC Generic Letter 89-10, 3
" Safety-Related Motor Operated Valve Testing and Surveillance," dated June 28, 1%19.
Arkansas Nuclear One-Unit 2 Respons_e:
As described above, the LTOP system for AND 2 dons not Incorporato PORVs (or control air systems).
The ANO-2 LTOP relief valves and associated block valves are within the scopo of the Inservice Testing Program of pumps and valvos for ANO-2 ' Engineering Programs Proceduro No. 1092.033).
This program is in compliance with Subsection IWV, "Innervico Testing of Valves in Nuclear Power Plants," of Section XI of the ASME Boiler and Pressure Vessel Code with exceptions authorized by the NRC.
LTOP rollof valves 2PSV-4732 and 2PSV-4742 are clas, fled as Category C valves por Subsection IWV in the SIMS Component Data Base.
The setpoints of the rollof valves are tested in accordance with Mechanical Porlodic Tests Proceduro No. 2306.09 during each refueling outage.
Block valves 2CV-4730-1, 2CV-4731-2, 2CV-4740-2 and 2CV-4741-1 are classified as Category B valves por Subsection IWV in the SIMS Component Data Base and will be stroke time tested in the open and closo directions during cold s_atdown.
The procedure that will be used for stroka time testing of the block valves is currently under developi ent and will bo issued and implemented during the 2R8 refueling outage.
l The LTOP block valves are included in t e ANO Motor Operated Valvo Testing and Surveillanco (MOVATS) program (Maintenance Administrative Procedure No.
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1025.011) in response to NRC Generic Letter 89-10.
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i Attachmont to 2CAN129013
' Page 6 NRC_ Staff _ Position _3._1, Item 3:
For operating PWR plants, modify the limiting conditions of operation of p0RVs and block valves in the technical specifications for Hodos 1, 2, and 3 to incorporate the position adopted by the staf f in recent licensing actions.
Attachments A-1 through A-3 are provided for guidance.
The staff recognizes that some roc atly licensed PWR plants already have tocht.ical specifications in accordance with the staf f position.
Such plants are already in compliance with this position and need merely state that in their response.
Those recent technical specifications require that plants that run with the clock 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 sont leakage is not permitted for period; of more than 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br />.
Arkansas Nuclear One-Unit 2 Response:
Entergy Operations, Inc. will proposo Technical Specification changes for ANO-2 that provido limiting conditions for operation in Modos 4, 5 ant' 6 for the low-temperature overprossure protect. ion system based on the guidanco provided in Attachment B-1 of Enclosure B.
The proposed Technical Specification changes can only utilize the guidance provided in Enclosure B since ANO-2 has a unique design for low-temperature overpressure protection.
The specification changos will address requirements for the LTop rollof valvos and associated block valves that are consistent with the intent of the requirements for p0RVs and block valvos identiflod in Attachment B-1 of Enclosure B to Generic Letter 90-06, the Bases (Attachment B-2) for these requirements and the gnidanco provided in Attachment B-3.
Entergy Operations, Inc. will also proposo Technical Specifications changes for ANO-2 that considor block valve operability in Modos 1, 2 and 3 for the lew-temperaturn overpressuro prc,tection system.
Since the design of ANO-2 for low-Lemperature overpressure protection is unique when compared to other Combustion Engineering designed _ plants, the Technical Specification changes provided in. Attachment A-1 of Enclosure A are not directly applicabic. The specification changes will address requirements for the block valvos and the Bases for these requirements.
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