ML17290A825
| ML17290A825 | |
| Person / Time | |
|---|---|
| Site: | Columbia  |
| Issue date: | 12/06/1993 |
| From: | Parrish J WASHINGTON PUBLIC POWER SUPPLY SYSTEM |
| To: | NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM) |
| Shared Package | |
| ML17290A826 | List: |
| References | |
| GO2-93-282, NUDOCS 9312160180 | |
| Download: ML17290A825 (22) | |
Text
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'e j DEMONSTION SYSTEM REGULATORY INFORMATION DISTRIBUTION SYSTEM (RIDS)
ACCESSION NBR:9312160180 DOC.DATE: 93/12/06 NOTARIZED: YES DOCKET FACIL:50-397 WPPSS Nuclear Project, Unit 2, Washington Public Powe 05000397 AUTH. NAME AUTHOR AFFILIATION PARRISH,J.V. Washington Public Power Supply System RECIP.NAME RECIPIENT AFFILIATION Document Control Branch (Document Control Desk) R
SUBJECT:
Application for amend to license NPF-21,revising TS 3/4.6.1.4, "MSIVLCS" to allow band of acceptable values for MSIVLCS blower dilution flow to be same in content as MSIVLCS improved TS.
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WASHINGTON PUBLIC POWER SUPPLY SYSTEM P.o. Boot 968 ~ 3000 George 1Wasbtrtgtort Way ~ Rlcblartd, 1Pasbtrtgtort 99352968 ~ (509) 372-5000 December 6, 1993 G02-93-282 Docket No. 50-397 U.S. Nuclear Regulatory Commission Attn: Document Control Desk Washington, D.C. 20555 Gentlemen:
Subject:
%NP-2, OPERATING LICENSE NPF-21 REQUEST FOR AMENDMENT TO TECHNICAL SPECIFICATION 3/4.6.1.4, MAIN STEAM ISOLATION VALVE LEAKAGE CONTROL SYSTEM
References:
Letter GO2-92-015, dated January 21, 1992, GC Sorensen (SS) to NRC, same subject 1',
In accordance with the Code of Federal Regulations, Title 10 Parts 50.90 and 2.101, the Supply System hereby submits a request for amendment to the WNP-2 Technical Specifications.
Specifically, the Supply System is requesting that the Main Steam Isolation Valve Leakage Control System (MSIVLCS) Specification be changed as attached to allow a band of acceptable values for MSIVLCS blower dilution flow (30 + 6 cfm), to be the same in content as the MSIVLCS Improved Technical Specifications (ITS), and to correct the Bases to reflect the changes in adapting the ITS and correct a typographical error. The Supply System has reviewed the MSIVLCS Technical Specifications as issued in NUREGs 1433 and 1434 and considers them to be clearer and more easily understood than the current WNP-2 MSIVLCS Specification.
Therefore, as provided for in SECY-93-067, "Final Policy Statement on Technical Specifications Improvements" the Supply System is requesting that this change request be considered as a line item improvement to the WNP-2 Technical Specifications.
The reason for proposing a change to this Specification is that the blower flow (presently 30 cfm, Surveillance 4.6.1.4.c.2) at which the vacuum is measured to prove operability cannot be consistently me'asured at precisely 30 cfm and a band of values is necessary to assure compliance to the Technical Specifications. Also, this Technical Specification change proposes an
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Page Two REQUEST FOR AMENDMENTTO TECHNICAL SPECIFICATIONS 3/4.6.1.4, MAINSTEAM ISOLATION VALVELEAKAGE CONTROL SYSTEM alternative method of verifying heater circuit integrity. Further, because the industry has been encouraged to adapt the ITS where possible, and because a change is required to blower dilution flow the ITS MSIVLCS Specification was evaluated for adaptation at WNP-2. As a result, the Supply System has evaluated the design requirements of the system and is proposing a tolerance band for measuring the blower dilution flow in addition to adapting the ITS MSIVLCS Specification. Adapting the NUREG 1433/1434 ITS MSIVLCS Specification consists of the following:
(5 A. Delete the descriptor "independent" from 3.6.1.4: "Two MSIV leakage control system (LCS) subsystems shall be OPERABLE." The independence of the two subsystems is a design feature beyond the capability of the operator to affect and an unnecessary term in considering system status from an operator's perspective.
B, Add an ACTION statement, 3.6.1.4.b, for inoperability of both subsystems.
Presently inoperability of both subsystems requires adherence to Limiting Condition for Operation 3.0.3 and an expedited shutdown.
C. Revise Surveillance 4.6.1.4.a.2, which measures current, with a requirement to verify electrical continuity.
D. Delete Surveillance 4.6.1.4.b which cycles depressurizing and steam isolation valves, as this requirement is addressed by Specification 4.0.5, ASME Section XI testing requirements. And, E. Relocate the specifics of the 18 month surveillance requirements, 4.6.1.4.c.1 and 4.6.1.4.c.2 that verify valve operation and blower suction, to the Bases.
It should be noted that Surveillance 4.6.1.4.d has been retained. The ITS removes 4.6.1.4.d (renumbered 4.6.1.4.c, the requirement for a Channel Function Test and Channel Calibration).
They were removed because the ITS considered them to be obvious indications of operability and verified in operability testing required by the ITS. The Supply System has decided to retain this Surveillance until total implementation of the ITS.
The MSIVLCS supplements the isolation function of the MSIVs by processing the fission products that could leak through the closed MSIVs after a Design Basis Accident (DBA) Loss of Coolant Accident (LOCA) and directing the leakage to the suction of the Standby Gas Treatment Units. It consists of two independent subsystems: an inboard subsystem, connected between the inboard and outboard MSIVs, and an outboard subsystem, connected downstream of the outboard MSIVs. Each subsystem is capable of processing leakage from the MSIVs following a DBA LOCA. After main steam line isolation and reactor depressurization following
Page Three REQUEST FOR AMENDMENTTO TECHNICAL SPECIFICATIONS 3/4.6.1.4, MAINSTEAM ISOLATION VALVELEAKAGE CONTROL SYSTEM a LOCA the subsystems are designed to depressurize their respective section of main steam piping once pressure decays to below 41 psig. The piping could remain pressurized post LOCA, Once depressurized MSIVLCS blowers draw and maintain a vacuum with respect to atmospheric pressure on the steam lines. The discharge from the MSIVLCS blowers is routed to the Standby Gas Treatment (SGT) System suction for processing prior to release.
A justification and significant hazards evaluation for each of the changes described above is as follows:
A. Deletion of "independent " from 3.6.1.4.
The independence of the two subsystems is a design feature and not affected by any controls available to the operator. It is a fixed condition that can only be changed by plant modification which is, in turn, controlled by the Code of Federal Regulations 10 CFR 50.59 process governing plant modifications. The "independence" of the subsystems cannot be altered by the operator, as such the term is an unnecessary description for. the operator to consider when evaluating the operability of the MSIVLCS.
This change is an editorial change and has no safety significance, however the Supply System has evaluated the proposed Technical Specification change and determined that it does not represent a significant hazards consideration because it does not:
- 1) Involve a significant increase in the probability or consequences of an accident previously evaluated. This is an administrative change that has no impact on the operation of the plant and cannot have a credible impact on the possibility or consequences of a previously evaluated accident. The change does not result in any hardware or operating procedure changes or in any manner contribute to the probability or consequences of a previously evaluated accident. Hence, it cannot increase the probability of a previously evaluated accident. Because it does not involve any equipment modifications or operating mode changes the consequences of an accident occurring with this change are the same as the consequences of an accident occurring without the change. Therefore, deletion of the word "independent" in Specification 3.6.1.4 will not increase the probability or consequences of a previously evaluated accident.
- 2) Create the possibility of a new or different kind of accident from any accident previously evaluated because the change does not introduce any new modes of plant operation nor does it require physical modification of the plant. Hence, the possibility of a new or different kind of accident than those previously evaluated is not created by this change.
Page Four REQUEST FOR AMENDMENTTO TECHNICAL SPECIFICATIONS 3/4.6.1.4, MAINSTEAM ISOLATION VALVELEAKAGE CONTROL SYSTEM
- 3) Involve a significant reduction in a margin of safety. An administrative change that has no impact on the operation of the plant cannot significantly impact the margin of safety created by the affected Specification. This change simplifies the understanding of the Specification. Because it does not have a technical or operational impact the margin of safety created by the specification is not significantly affected by the change.
B. Addition of Action 3.6.1.4.b.
This action allows, for a limited time, having both subsystems inoperable without being required to commence an expedited shutdown. The present Technical Specification allows one subsystem to be inoperable 30 days before commencing a shutdown.
However, because the inoperability of two subsystems is not addressed, if both subsystems become inoperable an expedited shutdown in accordance with Specification 3.0.3 is required. Under this condition, Action Statement 3.6.1.4.b would allow 7 days to return one of the inoperable subsystems to operable before commencing a shutdown.
With both subsystems inoperable MSIV leakage, post LOCA, will not be treated by the SGT System. However, significant improvements have been made in MSIV maintenance and leak tightness which further reduces the potential for the significant leakage the MSLC System was designed and installed for. The 7 day allowed outage time (AOT) is based on the low probability of the occurrence of a DBA LOCA over the 7 day period, the minimal risk of having both subsystems inoperable, and the offsetting risk of avoiding an expedited shutdown and exposure to potential transients during shutdown. Further, this is the same AOT that has been accepted in the Improved Technical Specifications, NVREGs 1433 and 1434.
The Supply System has evaluated the proposed Technical Specification change and determined that it does not represent a significant hazards consideration because it does not:
- 1) Involve a significant increase in the probability or consequences of an accident previously evaluated. The MSIVLCS is designed to mitigate accidents and is not capable of initiating an accident. Therefore, operation with both subsystems inoperable cannot increase the probability of a previously evaluated accident.
However, with both subsystems inoperable the ability to mitigate the consequences of a DBA LOCA is impacted. Leakage past the MSIVs willnot be processed through the SGT System, hence the consequences of a previously evaluated accident are increased. However, minor increases in containment leakage, such as the leakage through the MSIVs, have been found to have no significant impact on the risk to the public, and improved MSIV maintenance has
I Page Five REQUEST FOR AIVKNDMENTTO TECHNICAL SPECIFICATIONS, MAINSTEAM ISOLATION VALVELEAKAGE CONTROL SYSTEM consistently maintained observed leakage rates below the presently accepted 11.5 scfh per valve. Further, this increase in the consequences is also deemed to be slight because 7 days is the maximum time period that both subsystems will be out of service before action is commenced to shut down the plant and the probability of a DBA LOCA occurring during this period is small. Considering that minor leakage, as discussed above, has been found to have no significant impact on the risk to the public, and that the probability of a DBA LOCA occurring during the 7 day AOT is small, the actual probability of experiencing significant consequences is small. Also, the opportunity to avoid a plant shutdown by returning one of the units to service within the 7 day AOT offsets this slight increase in consequences because it avoids maneuvering the plant to shutdown conditions and allows the plant to remain at stable plant conditions.
Although acceptable, maneuvering to shutdown conditions has more inherent risk than operation at steady state. Therefore, the additional opportunity to avoid a shutdown maneuver offsets the risk of increased consequences that operating for the 7 day AOT, with both subsystems inoperable, represents. Hence, the probability or consequences of a previously evaluated accident are not significantly increased by the addition of this Action Statement.
- 2) Create the possibility of a new or different kind of accident from any accident previously evaluated because the change does not introduce any new modes of plant operation nor does it require physical modification of the plant. It does permit operation of the plant with equipment not capable of performing its safety function. However, loss of the collection and filtration function does not impact the reactor coolant pressure boundary or its support systems, and therefore, does not create the possibility of a new or different kind of accident from any previously analyzed accident.
.3) Involve a significant reduction in a margin of safety. The change may allow an increase in the unfiltered leakage following an accident. However, such small amounts of additional unfiltered leakage have been determined not to add significant risk to the general public. Further, as discussed above, the slight increase in risk is offset by the avoidance of a plant shutdown and the minimal risk therein and by the small probability of a DBA LOCA occurring during the 7 day AOT. For these reasons the change does not involve a significant reduction in the margin of safety.
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Page Six REQUEST FOR AMENDMENT TO TECHNICAL SPECIFICATIONS 3/4.6.1.4, MAINSTEAM ISOLATION VALVELEAKAGE CONTROL SYSTEM C. Revise Surveillance 4.6.1.4.a.2.
This change requires verifying electrical continuity instead of measuring current. The intent of this surveillance is to verify heater operability. Although a continuity check is not the same as a current measurement, system operation and system alarms provide a continuous indication of heater operability. The heaters are divided into two separate functions: temperature maintenance and heatup. During operation the maintenance heaters operate continuously and are designed to maintain temperatures between 265-275'F. Should temperature drop to 260'F the heatup heaters come on. If temperature decreases to 240'F an alarm alerts the operator of the situation so that action can be initiated to restore temperature. During system startup both heaters operate to raise system temperature into the operating range. Hence during system startup and operation, heater operability is confirmed by continuous temperature monitoring with an alarm to alert the operator if temperature cannot be maintained. The heaters are Thermon electrical resistance wire, magnesium oxide insulated in a stainless steel sheath. The expected failure mode is an impact to the sheathing causing a short which in turn causes the wire to overheat and open. Gradual degradation that could affect the capability of the cable to maintain temperature is not a known failure mode and would be noticed in the system alarm on decreasing temperatures. The heaters will either be operable, indicative of a continuous circuit, or be failed open. Both a continuity check or temperature monitoring alarm will be capable of discovering a failed heater. Plant surveillances verify, at acceptable frequencies, that power supply breaker alignment to the MSIVLC systems is correct. The continuous temperature monitoring and alarm provides assurance that the heaters are functioning correctly and meeting design specifications. Therefore,'ecause power supply will be assured and system operation, temperature monitoring and alarm functions assure that the heaters are functioning correctly a continuity check, rather than a current measurement, provides another appropriate method, in addition to temperature monitoring and alarm, of confirming heater operability.
Continuity can be verified by resistance measurements, rate of temperature increase, or current or wattage draw as compared to design. Any of these methods, combined with the temperature monitoring and alarm functions discussed above, confirm that the heaters are operable. Further, it is not necessary that the method of verification be of immediate attention to the operator and receive the same emphasis that other more dynamic plant parameters receive. Therefore, this requirement should be revised to allow the Plant Support Staff to choose the most appropriate method of verifying heater operability and control the activity by plant surveillance procedures.
L~L Page Seven REQUEST FOR AMENDMENTTO TECHNICAL SPECIFICATIONS 3/4.6.1A, MAINSTEAM ISOLATION VALVELEAKAGE CONTROL SYSTEM This change does not impact the ability of the operator to manage the plant. As'such, this change is an administrative change that reduces the amount of material confronting the operator in the Specifications and has no safety significance. The Supply System has evaluated this proposed change and determined that it does not represent a significant hazards consideration because it does not:
- 1) Involve a significant increase in the probability or consequences of an accident previously evaluated. This is an administrative change that has no impact on the operation of the plant and cannot have a credible impact on the possibility or consequences of a previously evaluated accident. The change does not result in any hardware or operating procedure changes or in any manner contribute to the probability or consequences of a previously evaluated accident. Plant surveillance procedures describing the method of verifying electrical continuity willchange but these have no significant impact on the operator's ability to operate the plant.
Hence, it cannot increase the probability of a previously evaluated accident.
Because it does not involve any equipment modifications or operating mode changes the consequences of an accident occurring with this change are the same as the consequences of an accident occurring without the change. The heaters will continue to be proven operable on the same schedule. Therefore, deletion of the prescriptive method by which operability is proven in Specification 3.6.1.4 will not alter the probability nor increase the consequences of a previously evaluated accident.
- 2) Create the possibility of a new or different kind of accident from any accident previously evaluated because the change does not introduce any new modes of plant operation nor does it require physical modification of the plant. Hence the possibility of a new or different kind of accident than those previously evaluated is not created by this change.
- 3) Involve a significant reduction in a margin of safety. An administrative change that has no impact on the operation of the plant cannot significantly impact the margin of safety created by the affected specification. This change simplifies the details of the specification without impacting the operability of the MSIVLCS subsystems. Continuous temperature monitoring and alarm on temperature loss will continue to prove the heaters operable. For these reasons this change does not represent a technical change to the operation of the heaters or plant, the system will provide a continuous surveillance of heater operability. Because it does not have a technical or operational impact the margin of safety created by the specification is not significantly affected by the change.
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Page Eight REQUEST FOR AMENDMENTTO TECHNICAL SPECIFICATIONS 3/4.6.1.4, MAINSTEAM ISOLATION VALVELEAKAGE CONTROL SYSTEM D. Delete Surveillance 4.6.1.4.b This surveillance is redundant to Specification 4.0.5, ASME Section XI testing requirements. As such, it serves no purpose to repeat these requirements in this specification. Adequate testing is now prescribed for these valves in the WNP-2 Pump and Valve Program which complies with Specification 4.0.5. For this reason the redundant requirement should be removed from the Specification. The WNP-2 Pump and Valve Program is controlled per 10 CFR 50.59, hence changes to it will be controlled and meet the criteria therein. In this manner, assurance is provided that this requirement will not,be arbitrarily changed and the degree of safety afforded by the specification not degraded.
This change does not impact the ability of the operator to manage the plant. It does not reduce the testing nor impact the technical capabilities of the subsystems. It eliminates a requirement redundant to an approved and accepted test program. As such, this change is an administrative change that reduces the amount of material confronting the operator in the specification and has no safety significance. However, the Supply System has evaluated the proposed change and determined that it does not represent a significant hazards consideration because it does not:
- 1) Involve a significant increase in the probability or consequences of an accident previously evaluated. This is an administrative change that does not impact the operation of the plant and cannot have a credible impact on the possibility or consequences of a previously evaluated accident. The valves will continue to be tested under the WNP-2 Pump and Valve Program. The change does not result in any hardware or operating procedure changes or in any manner contribute to the probability or consequences of a previously evaluated accident. As a result, this change does not represent a significant increase in the probability or consequences of a previously evaluated accident.
- 2) Create the possibility of a new or different kind of accident from any accident previously evaluated because the change does not introduce any new modes of plant operation nor does it require physical modification of the plant. No testing requirements are reduced as a result of this change. Hence, the possibility of a new or different kind of accident than those previously evaluated is not created by this change,
Page Nine REQUEST FOR AM<22fDMENT TO TECHNICAL SPECIFICATIONS 3/4.6.1.4, MAINSTEAM ISOLATION VALVELEAKAGE CONTROL SYSTEM
- 3) Involve a significant reduction in a margin of safety. An administrative change that has no impact on the operation of the plant cannot significantly impact the margin of safety created by the affected specification. This change simplifies the details of the specification without impacting the operability of the MSIVLCS
-subsystems. Because it does not have a technical or operational impact the margin of safety created by the specification is not significantly affected by the change.
E. Relocate the specifics of the 18 month surveillance'equirements, 4.6.1.4.c.l and 4.6.1.4.c.2, to the Bases and change the dilution flow measurement corresponding to
-17" H,O at the blower suction from 30 to 30 + 6 cfm.
The attached addition to the Bases addresses each requirement in surveillances 4.6.1.4.c.1 and 4,6.1.4.c.2. Procedures based on the current surveillances are in place that perform these tests. The procedures are controlled in accordance with 10 CFR 50.59, hence changes to the procedures will be controlled and reviewed per plant administrative controls. Moving the specifics of the testing to the Bases is in keeping with the guidance of. the Improved Technical Specifications and again removes detail tPat is not necessary for operator control of the plant. Because the details remain in the Bases, and remain as requirements, this change is administrative and has no safety significance.
The Supply System has evaluated the proposed change to move the details of surveillances 4.6.1.4.c.l and 4.6.1.4.c.2 to the Bases and determined that it does not represent a significant hazards consideration because it does not:
- 1) Involve a significant increase in the probability or consequences of an accident previously evaluated. This is an administrative change that does not impact the operation of the plant. The subsystems will continue to be tested in accordance with existing procedures which in turn will be controlled so that changes are not made without adequate safety review. The requirements will remain applicable and testing will continue to confirm adequate system operation. Relocating test specifics to the Bases in no way decreases the requirement to perform the tests.
The change does not result in any hardware or operating procedure changes or in any manner contribute to the probability or consequences of a previously evaluated accident. As a result, this change does not represent a significant increase in the pr'obability or consequences of a previously evaluated accident.
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Page Ten REQUEST FOR AMENDMENTTO TECHNICAL SPECIFICATIONS 3/4.6.1.4, MAINSTEAM ISOLATION VALVELEAKAGE CONTROL SYSTEM
- 2) Create the possibility of a new or different kind of accident from any accident previously evaluated because the change does not introduce any new modes of plant operation nor does it require physical modification of the plant. No testing requirements are reduced as a result of this change. Hence, the possibility of a new or different kind of accident than those previously evaluated is not created by this change.
- 3) Involve a significant reduction in a margin of safety. An administrative change that has no impact on the operation of the plant cannot significantly impact the margin of safety created by the affected specification. This change simplifies the details of the specification without impacting the operability of the MSIVLCS subsystems. Because it does not have a technical or operational impact the margin of safety created by the MSIVLCS surveillance tests is not significantly affected by the change.
In addition to relocating the specifics of the surveillances to the Bases it is requested that the dilution flow corresponding to at least -17" H,O at the suction blower be changed from 30 cfm to 30 + 6 cfm. As stated in the Bases, page B 3/4 6-2, the subsystems are required "to accommodate a leak rate of five times the Technical Specification leakage allowed for the MSIVs while maintaining a negative pressure downstream of the MSIVs." The allowed Technical Specification leakage is 11.5 scfli per valve. As discussed further in the submittal, the Bases states this value as 11.5 scfm, A correction to the Bases is also requested in this submittal. Five times the Technical Specification value for all four steam lines is a total of 230 scfli (3.8 scfm). Besides maintaining adequate vacuum with the blower, the blower dilution flow is also required to dilute the leakage drawn off to the point where given worst case flow, temperature and humidity dilution is such that the process stream delivered to the SGT is within the SGT capacity.
Accepting flow values of between 24 to 36 cfm provides adequate margin to the flow necessary to create sufficient vacuum to maintain proper operation of the MSIVLCS (design specification value of five times the Technical Specification allowed leakage) and is sufficient to maintain adequate margin to preserve blower operation given worst case conditions of flow, temperature and humidity. The proposed band (30 + 6 cfm) is adequate to meet the design requirements for leakage accommodation (maintaining a sufficient vacuum) and blower fan cooling. It is necessary to request a band of flow values because the measurement of the fiow rate is not precise enough to consistently measure 30 cfm and a band should be specified in order to maintain compliance with the WNP-2 Technical Specifications. Additionally, the minimum flow, 24 cfm, has enough margin above the design required flow so that degrading conditions will be recognized and corrective actions initiated before the flow can degrade below the design requirements.
Page Eleven REQUEST FOR AMENDMENTTO TECHNICAL SPECIFICATIONS 3/4.6.1.4, MAINSTEAM ISOLATION VALVELEAKAGE CONTROL SYSTEM The Supply System has evaluated the proposed change to allow an acceptable band of values (30 + 6 cfm) for dilution flow to the blower while maintaining at least -17"H>O vacuum at the blower suction and determined that it does not represent a significant hazards consideration because it does not:
- 1) Involve a significant increase in the probability or consequences of an accident previously evaluated. The MSIVLCS is not an active system and is started after a DBA LOCA, hence changes to the system cannot increase the probability of a previously evaluated accident. The system does not act in the initiation of a previously. evaluated accident. Because the minimum flow proposed, 24 cfm, can create the required system vacuum, dilute the worst case flow, temperature and humidity to within the capability of the SGT and maintain blower cooling, the ability of the system to limit the consequences of a previously evaluated accident is not affected. Further, the band is high enough above the design requirements so that degrading conditions will still be recognized and corrective action initiated well before jeopardizing the design capacity of the MSIVLCS. For these reasons this change does not represent a significant increase in the probability or consequences of a previously evaluated accident.
- 2) Create the possibility of a new or different kind of accident from any accident previously evaluated because the change does not introduce any new modes of plant operation nor does it require physical modification of the plant. No testing requirements are reduced as a result of this change. Significant fan degradation will not occur because the minimum allowed flow will be significantly above the required flow so that a degraded condition can be recognized and corrective action initiated before flow conditions degrade to the design requirements. As a result, the capability of the MSIVLCS willremain above the design requirements.
Hence, the possibility of a new or different kind of accident than those previously evaluated is not created by this change.
- 3) Involve a significant reduction in a margin of safety. As discussed above, the capability of the MSIVLCS to meet design requirements is not affected by this change.. Further, degraded conditions will continue to be recognized and corrected well before jeopardizing the capability of the MSIVLCS to meet design requirements. Hence, the margin of safety created by the MSIVLCS is not significantly affected by the change.
Page Twelve REQUEST FOR AMF22lDMENT TO TECHNICAL SPECIFICATIONS 3/4.6.1.4, MAINSTEAM ISOLATION VALVELEAKAGE CONTROL SYSTEM Also a typographical error in Bases 3/4.6.1.4, page B 3/4 6-2 requires correction. The Bases states that the allowed leakage rate value for each MSIV is 11.5 scfm, it should state 11.5 scfh as specified in Technical Specification Surveillance 3.6.1.2.c, page 3/4 6-2.
In considering adapting the ITS MSIVLCS Specification to WNP-2 the Supply System reviewed NUREGs 1433 and 1434 and determined that the MSIVLCS ITS could be adapted independently of the remainder of the ITS. There is no additional ITS Specification that the MSIVLCS Specification interacts with, supports, or is supported by, that in combination with the MSIVLCS Specification assures overall plant safety.
As discussed above, the Supply System concludes that these changes do not involve a significant hazards consideration, nor is there a potential for a significant change in the types or significant increase in the amount of any effluents that may be released offsite, nor does the change involve a significant increase in individual or cumulative occupational radiation exposure. Accordingly, the proposed change meets the eligibility criteria for categorical exclusion set forth in 10 CFR 51.22(C)(9) and therefore, per 10 CFR 51.22(b), an environmental assessment of these changes is not required.
This Technical Specification change request has been reviewed and approved by the WNP-2 Plant Operations Committee and the Supply System Corporate Nuclear Safety Review Board.
In accordance with 10 CFR 50.91, the State of Washington has been provided a copy of this letter.
. V. Parrish (Mail Drop 1023)
Assistant Managing Director, Operations PLP/bk Attachments cc: 'H Faulkenberry - NRC RV NS Reynolds - Winston & Strawn JW Clifford - NRC DL Williams - BPA/399 NRC Site Inspector - 901A W Bishop - EFSEC
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