RBG-46870, License Amendment Request (LAR 2008-08) Surveillance Frequency Extension Request

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License Amendment Request (LAR 2008-08) Surveillance Frequency Extension Request
ML083460043
Person / Time
Site: River Bend Entergy icon.png
Issue date: 12/08/2008
From: Roberts J
Entergy Operations
To:
Document Control Desk, Office of Nuclear Reactor Regulation
References
RBF1-08-0148, RBG-46870
Download: ML083460043 (18)
v • d • e


Text

Entergy Operations, Inc.

River Bend Station 5485 U. S. Highway 61 N

'd Entergy St. Francisville, LA 70775 Tel 225 381 4149 Fax 225 635 5068 jrober3@entergy.com Jerry C. Roberts Director, Nuclear Safety Assurance December 8, 2008 U. S. Nuclear Regulatory Commission Attn: Document Control Desk Washington, DC 20555

SUBJECT:

License Amendment Request (LAR 2008-08)

Surveillance Frequency Extension Request River Bend Station - Unit I Docket No. 50-458 License No. NPF-47 RBG-46870 RBF1-08-0148

Dear Sir or Madam:

Pursuant to 10 CFR 50.90, Entergy Operations, Inc. (Entergy) hereby requests an amendment for River Bend Station - Unit 1 (RBS). The proposed amendment adds a license condition for a one-time extension of a limited number of Technical Specification (TS) Surveillance Requirements (SRs) to account for the effects of rescheduling the next refueling outage (RF15) from early 2009 to late 2009. The proposed extension is two months.

The affected surveillances involve the 18-month channel calibration and logic system functional tests for one specific channel of the reactor water level instrumentation system. This instrumentation provides signals to the following functions: main steam line isolation, primary containment and drywell isolation, reactor water cleanup system isolation, secondary containment and fuel building isolation, and the control room fresh air system.

The surveillances being extended were performed on September 28, 2007, during a plant outage. The next required due date, including the 25% allowed extension time, is August 15, 2009. Based on the original schedule for RF15, this surveillance performance schedule was acceptable. When the date for RF15 was recently moved from early 2009 to late 2009, the need for an extension of two months was recognized.

The decision to request the extension was based upon the need to avoid plant configurations or activities that are inappropriate during plant operation. In particular, the surveillance for the reactor water level instrumentation would increase the potential for a

-ADOI

plant transient. Therefore, this extension request was deemed more prudent than performing-the surveillance on-line.

Moving the RF15 outage date will allow the station to optimize the fuel burnup for the current cycle. This has been necessitated by the duration of RF14, and unplanned outage time since then, the majority of which resulted directly from the effects of Hurricane Gustav.

This surveillance is scheduled to be performed during a shutdown of sufficient duration should one occur prior to RF1 5.

The proposed change has been evaluated in accordance with 10 CFR 50.91 (a)(1) using criteria in 10 CFR 50.92(c) and it has been determined that this change involves no significant hazards consideration. The bases for these determinations are included in the attached submittal. The proposed change does not include any new commitments.

The NRC has approved surveillance extensions for delayed refueling outages at other plants, including Kewaunee in 2006 and Cooper in 2004. The surveillance associated with the reactor water level instrument channel is currently required to be performed by August 15, 2009. Therefore, Entergy requests approval of the proposed amendment by August 1, 2009, to avoid a shutdown to perform the surveillance.. Once approved, the amendment shall be implemented within 15 days. Although this request is neither exigent nor emergency, your prompt review is, requested.

If you have any questions or require additional information, please contact David Lorfing at 225-381-4157.

I declare under penalty of perjury that the foregoing is true and correct. Executed on December 8, 2008.

Sincerely,

,ý4Je~rry C.ýRoberts Director, Nuclear Safety Assurance Attachments:

1. Analysis of Proposed Technical Specification Change
2. Proposed Technical Specification Changes (mark-up) cc: Regional Administrator U. S. Nuclear Regulatory Commission Region IV 612 E. Lamar Blvd., Suite 400 Arlington, TX 76011-4125

NRC Senior Resident Inspector P. O. Box 1050 St. Francisville, LA 70775 U.S. Nuclear Regulatory Commission Attn: Mr. Carl F. Lyon Washington, DC 20555-0001 Jeffrey P. Myers Louisiana Dept. of Environmental Quality Attn: OEC-ERSD P.O. Box 4312 Baton Rouge, LA 70821 -4312

Attachment 1 RBG-46870 Analysis of Proposed Technical Specification Change

RBG-46870 Page 1 of 12

1.0 DESCRIPTION

This evaluation supports a request to amend Operating License NPF-47 for River Bend Station - Unit 1 (RBS).

The proposed change will add a License Condition that allows specific Technical Specifications (TS) surveillance intervals to be extended on a one-time basis for the 15th fuel cycle. The proposed extension is two months. The affected surveillances involve the 18-month channel calibration and logic system functional tests for one specific channel of the reactor water level instrumentation system. The reactor water level instruments provide signals to the following functions: main steam line isolation, primary containment and drywell isolation, reactor water cleanup system (RWCU) isolation, secondary containment and fuel building isolation, and the control room fresh air system (CRFA).

2.0 PROPOSED CHANGE

The proposed change will extend these TS surveillance intervals on a one-time basis to account for the effects of delaying the next refueling outage. Specifically, Entergy proposes to add the following License Condition to paragraph 2.C. of NPF-47.

(21) Temporary Surveillance Interval Extensions During the 15th fuel cycle, in lieu of the Technical Specification specified frequencies, the maximum allowed surveillance test interval for the following Surveillance Requirements will be 24.5 months.

TS Function Surveillance Requirement TS Table 3.3.6.1-1 Function 1.a, SR 3.3.6.1.5, Channel Calibration, Main Steam Line Isolation, and, Reactor Vessel Level - Low Low SR 3.3.6.1.6, Logic System Functional Low, Level 1, Channel A Test TS Table 3.3.6.1-1 Function 2.a, SR 3.3.6.1.5, Channel Calibration, Primary Containment and Drywell and, Isolation, Reactor Vessel Water SR 3.3.6.1.6, Logic System Functional Level - Low Low, Level 2, Test Channel A TS Table 3.3.6.1-1 Function 4J, SR 3.3.6.1.5, ChannelCalibration, Reactor Water Cleanup System and, Isolation, Reactor Vessel Level - SR 3.3.6.1.6, Logic System Functional Low Low, Level 2, Channel A Test TS Table 3.3.6.2-1 Function 1, SR 3.3.6.2.4, Channel Calibration, Secondary Containment and Fuel and, Building Isolation, Reactor Vessel SR 3.3.6.2.5, Logic System Functional Water Level - Low Low, Level 2, Test Channel A

RBG-46870 Page 2 of 12 TS Table 3.3.7.1 Function 1, SR 3.3.7.1.4, Channel Calibration, Control Room Fresh Air System and, Instrumentation, Reactor Vessel SR 3.3.7.1.5, Logic System Functional Water Level - Low Low, Level 2, Test Channel A There are no proposed changes to the TS BASES.

3.0 BACKGROUND

The affected surveillances involve the 18-month channel calibration and logic-system functional tests for one specific channel of the reactor water level instrumentation system. This instrumentation provides signals to the following functions: main steam line isolation, primary containment and drywell isolation, reactor water cleanup system isolation, secondary containment and fuel building isolation, and the control room fresh air system.

The surveillances being extended were performed on September 28, 2007, during a plant outage. Its next required due date including the 25% allowed extension time is August 15, 2009. Based on the schedule for RF15 in the spring 2009, this surveillance performance schedule was acceptable. When the date for RF15 was recently moved from the spring 2009 to the fall 2009, the need for an extension of two months was recognized. The decision to. request the extension was based upon the need to avoid plant configurations or activities that are inappropriate during plant operation. In particular, the surveillance for the reactor water level instrumentation would increase the potential for a plant transient. Therefore, the extension request was deemed more prudent than performing the surveillance on-line.

Moving the RF15 outage date will allow the station to optimize the fuel burnup for the current cycle. This has been necessitated by the duration of RF14, and unplanned outage time since then, the majority of which resulted directly from the effects of Hurricane Gustav.

This surveillance is scheduled to be performed during a shutdown of sufficient duration should one occur prior to RF1 5.

The normal surveillance test interval for the subject SRs is 18 months. For scheduling purposes, Entergy uses 550 days as the surveillance interval. Using the maximum extension of 25 percent of the surveillance interval allowed by TS 3.0.2ý the 18-month surveillance requirement must be completed within 22.5 months (i.e., within 687 days) of its last performance. The surveillance interval plus the allowed extension will be exhausted on August 15, 2009.

SR 3.0.1 states that failure to perform a surveillance within the specified frequency shall be failure to meet the Limiting Condition for Operation (LCO), except as provided in SR 3.0.3. Therefore, once the surveillance is not completed within the specified frequency (i.e., within 18 months plus the 25% extension allowed Ly LCO 3:0.2), the associated

RBG-46870 Page 3 of 12 LCOs would have to be considered not met and the plant would have to comply with the TS actions. There is one surveillance test procedure affected by the delayed refueling outage. This test procedure pertains to one specific channel of the reactor water level instrumentation system. Since the instruments provide multiple functions, multiple SRs are affected by the test. The particular surveillances and functions affected are discussed below.

3.1 Reactor Water Level Instrumentation Surveillances Surveillance Test Procedure (STP)-051-4201, "NSSSS - Reactor Vessel Water Level -

Low Low Level 2, Low Low Low Level 1 Channel Calibration Test and Logic System Functional Test," was last performed on September 28, 2007. The STP affects only the "A" channel of a four-channel instrumentation system and must be performed by August 15, 2009, to meet the specified TS frequency requirement (within 18 months plus the 25% extension allowed by LCO 3.0.2). The remaining three channels do not require an extension.

Portions of this STP are scheduled to be performed during plant shutdown to avoid potentially causing a plant transient. While this STP can be performed during power operations, there are multiple reactor water level instruments associated with a common reactor level reference tap. If some or all of these instruments were actuated, they could cause a half-trip signal to the associated actuation logic, including the reactor protection system (RPS) and emergency core cooling system (ECCS) actuation logic.

If the test were to be performed during power operations, it would be necessary to bypass or render inoperable a number of other functions to avoid possible actuations associated with. this reactor vessel water level instrumentation tap point. Instrumentation associated with this tap point, in addition to those functions tested by this STP, that may be bypassed or rendered inoperable includes:

  • RPS scram signals on reactor water level,
  • reactor recirculation system pump trip signals,

The STP was planned to be performed during RF15, previously scheduled early in 2009.

However the outage has been delayed until late 2009.

SR 3.0.1 states that failure to perform a surveillance within the specified frequency shall be failure to meet the LCO, except as provided in SR 3.0.3. Therefore, once the surveillance is considered late, the affected channel would have to be placed in a tripped condition to comply with the TS Actions.

If the affected channel was placed in the tripped condition as required by the TS Actions, a single failure of the redundant instrument channel could cause a plant transient, such as a complete isolation of all MSIVs. Operating for over a month with the channel in trip

RBG-46870 Page 4 of 12 increases the potential for a plant transient. Because of the increased potential for a plant transient, Entergy believes it is prudent to avoid performing the STP during power operations or continuing to operate with the channel in the tripped condition. ,

This STP performs channel calibrations and logic system functional tests for reactor water level transmitter B21-LTNO81A and associated trip units B21-ESN681A and B21-ESN682A. Trip unit B21-ESN681A actuates on Reactor Vessel Water Level -'Low Low Low, Level 1, and trip unit B21 -ESN682A actuates on Reactor Vessel Water Level - Low Low, Level 2.

The required TS functions affected by the STP are primary containment and drywell isolation instrumentation, secondary containment and fuel building isolation instrumentation, and CRFA system instrumentation. The following table provides specific information on each affected TS function and associated TS surveillance requirements.

TS Function Affected Surveillance Requirements TS Table 3.3.6.1-1 Function 1.a, SR 3.3.6.1.5, Channel Calibration, Main Steam Line Isolation, and, Reactor Vessel Water Level - Low SR 3.3.6.1.6, Logic System Low Low, Level 1 Functional Test TS Table 3.3.6.1-1 Function 2.a, SR 3.3.6.1.5, Channel Calibration, Primary Containment and Drywell and, Isolation, Reactor Vessel Water SR 3.3.6.1.6, Logic System Level - Low Low Low, Level 1 Functional Test TS Table 3.3.6.1-1 Function 4.i, SR 3.3.6.1.5, Channel Calibration, RWCU System Isolation, Reactor and, Vessel Water Level - Low Low, SR 3.3.6.1.6, Logic System Level 2 Functional Test TS Table 3.3.6.2-1 Function 1, SR 3.3.6.2.4,Channel Calibration, Secondary Containment and Fuel and, Building Isolation, Reactor Vessel SR 3.3.6.2.5, Logic System Water Level - Low Low, Level 2 Functional Test TS Table 3.3.7.1 Function 1, SR 3.3.7.1.4, Channel Calibration, CRFA System Instrumentation, and, Reactor Vessel Water Level - Low SR 3.3.7.1.5, Logic System Low, Level 2 Functional Test 4.0 Technical Analysis Entergy has evaluated the effect of extending the surveillance intervals on a one-time basis and has concluded that the extensions are acceptable. The basis for this conclusion is provided below.

RBG-46870 Page 5 of 12 4.1 Reactor Water Level Instrumentation Surveillance Entergy is requesting a one-time surveillance interval extension of 2 months for the "A" channel of a four-channel reactor vessel water level instrumentation logic system. The reactor vessel water level signals for the affected functions are initiated from four level transmitters that sense the difference between the pressure due to a constant column of water (reference leg) and the pressure due to the actual water level (variable leg) in the vessel. The level transmitters provide signals to two associated trip units that actuate the above listed mitigation functions. The instrumentation devices affected by the surveillance extension are reactor water level transmitter B21-LTN081A and associated trip units B21-ESN681A and B21-ESN682A.

Trip unit B21-ESN681A actuates on Reactor Vessel Water Level - Low Low Low, Level 1 to provide the "A" channel isolation signal to the main steam lines and main steam line drain valves. Trip unit B21-ESN682A actuates on Reactor Vessel Water Level - Low Low, Level 2 to provide the "A" channel isolation signal to primary containment and drywell isolation valves, and the secondary containment and fuel building isolation valves. The Level 2 signal also starts the standby gas treatment system (GTS) and the CRFA system. These isolation functions are provided to limit fission product release during and following postulated design basis accidents (DBAs), such that offsite radiation exposures are maintained within the requirements of 10CFR50.67. The function of the CRFA System is to provide a radiologically controlled environment to ensure the habitability of the control room for the safety of control room operators.

The interval extension from 22.5 months to 24.5 months for the subject surveillances was evaluated based upon the following:

1. The TS requires other, more frequent surveillances that provide assurance that the instrumentation system remains operable.
2. The affected channel has demonstrated consistent reliability during previous surveillances, and there are no outstanding maintenance or operating experience issues that affect performance of the system, or that would affect performance with an extended test interval.
3. The current instrument settings and acceptance limits have been calculated assuming that the surveillance intervals are 30 months, which bounds the requested extension to 24.5 months.
4. Adequate defense-in-depth is provided through redundancy and diversity of the instrumentation system design. The instrumentation logic for each of the above functions is designed with sufficient defense-in-depth such that a failure of a single channel will not prevent the function from occurring nor cause an inadvertent actuation of the function. Additionally, there are other diverse methods of automatically isolating the affected systems to limit the release of radioactive material to the environment in the event of a DBA. Also each of the functions can be actuated manually from the control room.

These considerations are discussed in more detail in the following sections.

RBG-46870 Page 6 of 12 4.1.1 Testing and Reliability of the Affected Instruments The TS requires other more frequent surveillances that help to ensure that the instrumentation system is operable between performance of the 18-month calibration and the 18-month logic system functional test. SR 3.3.6.1.2, SR 3.3.6.1.3, SR 3.3.6.2.2, SR 3.3.6.2.3, SR 3.3.7.1-2, and SR 3.3.7.1.3 require channel functional tests and trip unit calibrations of the instrument system on a 92-day frequency. This includes a calibration of trip units B21-ESN681 A and B21-ESN682A, if necessary. 'A review of the last six performances of these surveillances shows that they were performed successfully and that the trip unit setpoints were within calibration tolerances.

In addition, the TS requires a channel check of the instrumentation to be performed on a 12-hour frequency (SR 3.3.6.1.1, SR 3.3.6.2.1, and SR 3.3.7.1.1). A channel check is typically a comparison of the parameter indicated on one channel to a similar parameter on other channels. It is based on the assumption that instrument channels monitoring the same parameter should read approximately the same value. The channel check is performed once every 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> primarily to ensure that a gross failure of instrumentation has not occurred. Abnormal instrument readings can also be indicative of instrument problems occurring prior to gross failure, such as a 'channel transmitter not indicating water level as accurately as other channels. The surveillance procedure for the channel checks requires any abnormal readings to be identified and reported to the Operations Shift Manager.

The last four performances of the 18 month channel calibrations and logic system functional tests for these functions were reviewed and found to be performed satisfactorily with the instrument loop setpoints within calibration tolerances. The maximum drift of the setpoint values between these surveillances, the longest interval being 19 months, was less than 0.3 inches water column. Since there is a four inch margin between the nominal trip setpoint and the TS allowable value, the expected setpoint drift for the extended interval of 24.5 months is insignificant. In addition, there are no outstanding maintenance or operating experience issues that affect performance of the system, or that would adversely affect performance with an extended test interval.

4.1.2 Instrument Setpoint Calculations No new calculations were needed to determine the effect of the extended surveillance interval. The current instrument settings and acceptance limits were calculated based upon a 24-month operating cycle, although RBS currently operates on a nominal 18-month cycle. That is, the calculations assume that the surveillance intervals are 30 months apart (24 months plus a 25% allowed extension). This bounds the requested extension to 24.5 months.

r The RBS methodology for calculating instrument setpoints is described in the Updated Safety Analysis Report (USAR) section 7.1.2.5 and in RBS Engineering Department Guide EDG-EE-003, "Methodology for the Generation of Instrument Loop Uncertainty &

Setpoint calculations." As discussed in USAR section 7.1.2.5, the methodology used in determining NSSS safety system setpoints is documented in NEDC-31336P-A, "General Electric Instrument Setpoint Methodology." This document was developed by the

RBG-46870 Page 7 of 12 Instrument Setpoint Methodology Owners Group (ISMG) and approved by the Staff on February 9, 1.993.

RBS Engineering Department Guide EDG-EE-003 establishes a calibration tolerance or "as-left" band above and/or below the desired output. Plant procedures require any as-found setpoints outside of the calibration tolerance band to be returned to within the band. The calibration tolerance band is typically equal to plus or minus the instrument accuracy.

The following tables provide summaries of calculation results performed for a 30-month calibration interval and comparisons to analytical and TS limits.

B21-ESN681A, Reactor Vessel Level - Low Low Low, Level 1 Analytical Calculated Tech Spec AV Calculated Actual NTSP Limit Allowable Nominal Trip Setting Value (AV) Setpoint (NTSP)

-158.8 in. > -149.025 in. > -147.0 in. -146.025 in. -143.0 in.

Loop Channel Drift Total Loop M&TE Maximum Uncertainty Uncertainty Accuracy Loop Tolerance (As-

_,_ left Band)

+ 4.299 in. + 4.303 in. + 6.771 in. + 0.446 in. + 1.4 in.

B21 -ESN682A, Reactor Vessel Level - Low Low, Level 2 Analytical Calculated AV Tech Spec AV Calculated Actual NTSP Limit NTSP Setting

-53.8 in. > -49.47 in. > -47.0 in. -45.81 in. -43.0 in.

Loop Channel Drift Total Loop M&TE Maximum Uncertainty Uncertainty Accuracy Loop Tolerance (As-left Band)

+ 4.33 in. + 4.644 in. + 7.113 in. + 0.444 in. + 1.4 in.

As can be seen from the above tables, the calculated allowable values and the calculated nominal trip setpoints are conservative relative to the TS limits. Actual NTSPs in plant procedures provide margin to the calculated NTSP. In addition, calibration tolerance bands are established by plant .procedures that are within the maximum tolerance used in the calculations.

4.1.3 Defense-in-Depth for Affected Instrument Functions Adequate defense-in-depth is provided through redundancy and diversity of the instrumentation system design. The instrumentation logic for each of the affected

RBG-46870 Page 8 of 12 functions is designed with sufficient defense-in-depth such that a failure of a single channel will not prevent the function from occurring or cause an inadvertent actuation of the function. This defense in depth ensures that safety is maintained. Additional details on these capabilities are described below for each affected function.

TS Table 3.3.6.1-1 Function 1.a, Main Steam Line Isolation, Reactor Vessel Water Level

- Low Low Low, Level 1 Low reactor pressure vessel (RPV) water level indicates that the capability to cool the fuel may be threatened. Therefore, isolation of the main steam isolation valves (MSIVs) and other interfaces with the reactor vessel occurs to prevent offsite dose limits from being exceeded. The Reactor Vessel Water Level - Low Low Low, Level 1 function is one of the many functions capable of providing isolation signals. Other instrumentation provided for MSIV isolation includes: low main steam line pressure, high main steam line flow, low main condenser vacuum, and high main steam line tunnel temperature. ,

The main steam line Level 1 isolation logic is one-out-of-two taken twice, by which, upon actuation of channel A or C and channel B or D, all the MSIVs close. The main steam line drain valve isolation logic is two-out-of-two, by which, upon actuation of channels A and D, the outboard main steam line drains close. Upon actuation of channels B and C, the inboard main steam line drains close. Therefore, the failure of a single channel will not prevent the isolation function from being completed.

TS Table 3.3.6.1-1 Function 2.a, Primary Containment and Drywell Isolation, Reactor Vessel Water Level - Low Low, Level 2 Low RPV water level indicates the capability to cool the fuel may be threatened. The valves whose penetrations communicate with the primary containment are isolated to limit the release of fission products. The Reactor Vessel Water Level - Low Low, Level 2 function associated with isolation is implicitly assumed in the analysis, as these leakage paths are assumed to be isolated post LOCA. In addition, Function 2.a provides an isolation signal to certain drywell isolation valves. The isolation of the drywell isolation valves, in combination with other accident mitigation systems, functions to ensure that steam and water releases to the drywell are channeled to the suppression pool to maintain the pressure suppression function of the primary containment. The isolation also includes the actuation of the GTS and CRFA systems.

The containment isolation valve logic is two-out-of-two, where actuation of channels A and D will isolate the outboard containment isolation valves and initiate "A" train components, Actuation of channels B and C will isolate the inboard containment isolation valves and initiate "B" train components. Therefore, the failure of a single channel will not prevent the isolation function from being completed.

TS Table 3.3.6.1 -1 Function 4.i, Reactor Water Cleanup (RWCU) System Isolation, Reactor Vessel Water Level - Low Low, Level 2 Low RPV water level indicates the capability to cool the fuel may be threatened.

Therefore, isolation of some reactor vessel interfaces occurs to isolate the potential

RBG-46870 Attachment 1 Page 9 of 12 sources of a break. The isolation of the RWCU system on Level 2 supports actions to ensure that fuel peak cladding temperature remains below the limits of 1 OCFR50.46.

The Reactor Vessel Water Level - Low Low, Level 2 function associated with RWCU isolation is not directly assumed in any transient or accident analysis, since bounding analyses are performed for large breaks such as main steam line breaks.

The isolation valve logic is two-out-of-two, where actuation of channels A and D will isolate the outboard containment isolation valves. Actuation of channels B and C will isolate the inboard containment isolation valves. Therefore, the failure of a single channel will not prevent the isolation function from being completed.

TS Table 3.3.6.2-1 Function 1, Secondary Containment and Fuel Building Isolation, Reactor Vessel Water Level - Low Low, Level 2 Low RPV water level indicates that the capability to cool the fuel may be threatened. An isolation of the secondary containment and actuation of the GTS system are initiated in order to minimize the potential of an offsite dose release. The Reactor Vessel Water Level - Low Low, Level 2 function is one of the functions assumed to be operable and capable of providing isolation and initiation signals. Other instrumentation provided for secondary containment and fuel building isolation includes: high drywell pressure, high fuel building ventilation exhaust radiation, and manual initiation.

The isolation valve logic is two-out-of-two where actuation of channels A and D will isolate one division of isolation valves. Actuation of channels B and C will isolate the redundant division of isolation valves. Therefore, the failure of a single channel will not prevent the secondary containment isolation function from being completed.

TS Table 3.3.7.1 Function 1, Control Room Fresh Air (CRFA) System Instrumentation, Reactor Water Level - Low Low, Level 2 Low RPV water level indicates that the capability to cool the fuel may be threatened. A low reactor vessel water level could indicate a LOCA, and will automatically initiate the CRFA system, since a LOCA could be a precursor to a potential radiation release and subsequent radiation exposure to control room personnel. The CRFA system will also automatically initiate on a high drywell pressure signal or a control room local intake ventilation high radiation level signal.

The instrumentation logic for the Level 2 function is two-out-of-two, where actuation of channels A and D will isolate the control room and initiate CRFA train "A". Actuation of channels B and C will isolate the control room and initiate CRFA train "B". Therefore, the failure of a single channel will not prevent the control room isolation or the initiation of the CRFA system from being completed. This defense in depth ensures the safety function is maintained.

RBG-46870 Page 10 of 12

5.0 REGULATORY ANALYSIS

5.1 Applicable Regulatory Requirement Criteria The proposed changes have been evaluated to determine whether applicable regulations and requirements continue to be met.

Entergy has determined that the proposed changes do not require any exemptions or relief from regulatory requirements other than the TS, and do not affect conformance with any General Design Criterion (GDC) differently than described in the Updated Final Safety Analysis Report (UFSAR.)

10CFR50.36 sets forth the regulatory requirements for the content of the TS. This regulation requires, in part, that the TS contain SRs. 10CFR50.36(c)(3), states that SRs to be included in the TS are those relating to test, calibration, or inspection which assure that the necessary quality of systems and components is maintained, that facility operation will be within safety limits, and that the LCO will be met.,The proposed changes to the SRs are for a temporary extension of certain surveillance intervals, which are not specified in the regulations.

5.2 No Significant Hazards Consideration Entergy is proposing to extend certain surveillance intervals on a one-time basis to account for the effects of delaying the start of RF1 5. The affected surveillances involve the 18-month channel calibration and, logic system functional tests for one channel of a particular reactor water level instrument system. The reactor water level instrument channel provides an automatic signal to the following functions: main steam line isolation, primary containment and drywell isolation, RWCU system isolation, secondary containment and fuel building isolation, and the CRFA system.

Entergy has evaluated whether a significant hazards consideration is involved with the proposed amendment by focusing on the three standards set forth in 10CFR50.92, "Issuance of Amendment," as discussed below:

1. Does the proposed change involve a significant increase in the probability or.

consequences of an accident previously evaluated?

Response: No.

The requested action is a one-time extension to the performance interval of certain TS surveillance requirements. The performance of the surveillances, or the failure to perform the surveillances, is not a precursor to an accident.

Performing the surveillances or failing to perform the surveillances does not affect the probability of an accident. Therefore, the proposed delay in performance of the surveillance requirements in this amendment request does not increase the probability of an accident previously evaluated.

A delay in performing the surveillances does not result in a system being unable to perform its required function. Additionally, the defense in depth of the system

RBG-46870 Page 11 of 12 design provides additional confidence that the safety function is maintained. In the case of this one-time extension request, the relatively short period of additional time that the systems and components will be in service before the next performance of the surveillance will not affect the ability of those systems to operate as designed. Therefore, the systems required to mitigate accidents will remain capable of performing their required function. No new failure modes have been introduced because of this action and the consequences remain consistent with previously evaluated accidents. Therefore, the proposed delay in performance of the surveillance requirement in this amendment request does not involve a significant increase in the consequences of an accident.

Therefore, the proposed change does not involve a significant increase in the probability or consequences of an accident previously evaluated.

2. Does the proposed change create the possibility of a new or different kind of accident from any accident previously evaluated?

Response: No.

The proposed amendment does not involve a physical alteration of any system, structure, or component (SSC), or a change in the way any SSC is operated. The surveillance intervals of the level instrumentation are currently evaluated for 30 months, which bounds the requested interval extension. The proposed amendment does not involve operation of any SSCs in a manner or configuration different from those previously recognized or evaluated. No new failure mechanisms will be introduced by the one-time surveillance extension being requested.

Therefore, the proposed change does not create the possibility of a new or different kind, of accident from any previously evaluated.

3. Does the proposed change involve a significant reduction in a margin of safety?

Response: No.

The proposed amendment is a one-time extension of the performance-interval of certain TS surveillance requirements. Extending the surveillance requirements does not involve a modification of any TS Limiting Conditions for Operation.

Extending the surveillance frequency does not involve a change to any limit on accident consequences specified in the license or regulations. Extending the surveillance frequency does not involve a change to how accidents are mitigated or a significant increase in the consequences of an accident. Extending the surveillance frequency does not involve a change in a methodology used to evaluate consequences of an accident. Extending the surveillance frequency does not involve a change in any operating procedure or process. The surveillance intervals of the level instrumentation are currently evaluated for 30 months which bounds the requested interval extension.

RBG-46870 Page 12 of 12 The components involved in this request have exhibited reliable operation based on the results of the most recent performances of their 18-month surveillance requirements and the associated functional surveillances.

Based on the limited additional period of time that the systems and components will be in service before the surveillance is next performed, as well as the operating experience that these surveillances are typically successful when performed, it is reasonable to conclude that the margin of safety associated with the surveillance requirement will not be affected by the requested extension.

Therefore, the proposed change does not involve a significant reduction in a margin of safety.

Based on the above, Entergy concludes that the proposed amendment presents no significant hazards consideration under the standards set forth in 10CFR50.92(c), and, accordingly, a finding of "no significant hazards consideration" is justified.

5.3 Environmental Consideration The proposed amendment does not involve (i) a significant hazards consideration, (ii) a significant change in the types or significant increase-in the amounts of any effluent that may be released offsite, or (iii) a significant increase in individual or cumulative occupational radiation exposure. Accordingly, the proposed amendment meets the eligibility criterion for categorical exclusion set forth in 1 0CFR51.22(c)(9). Therefore, pursuant to 10CFR51.22(b), no environmental impact statement or environmental assessment need be prepared in connection with the proposed amendment.

6.0 Precedence The NRC approved a similar request to extend certain TS surveillances on a one-time basis due to the effects of a delayed outage for the Kewaunee Power Station by issuance of Amendment No. 187 dated July 12, 2006 (TAC No. MC9782, ADAMS Accession No. ML061640286).

The NRC also approved a similar request to extend certain TS surveillances on a one-time basis due to the effects of a delayed outage for the Cooper Nuclear Station by issuance of Amendment No. 205 dated July 14, 2004 (TAC No. MC1914, ADAMS Accession No. ML041960078).

The Entergy request for a license amendment is similar to the Kewaunee and Cooper requests, but is more limited in scope.

Attachment 2 RBG-46870 Proposed License Condition Changes (mark-up)

RBG-46870 Page 1 of 1 INSERT for License No. NPF-47 (New page 6d)

- 6d -

(21) Temporary Surveillance Interval Extensions During the 15th fuel cycle, in lieu of the Technical Specification specified frequencies, the maximum allowed surveillance test interval for the following Surveillance Requirements will be 24.5 months.

TS Function Surveillance Requirements TS Table 3.3.6.1-1 Function 1.a, Main SR 3.3.6.1.5, Channel Calibration, and, Steam Line Isolation, Reactor Vessel SR 3.3.6.1.6, Logic System Functional Water Level - Low Low Low, Level 1 Test TS Table 3.3.6.1-1 Function 2.a, Primary SR 3.3.6.1.5, Channel Calibration, and, Containment and Drywell Isolation, SR 3.3.6.1.6, Logic System Functional Reactor Vessel Water Level - Low Low Test Low, Level 1 TS Table 3.3.6.1-1 Function 4.i, Reactor SR 3.3.6.1.5, Channel Calibration, and, Water Cleanup System Isolation, Reactor SR 3.3.6.1.6, Logic System Functional Vessel Water Level - Low Low, Level 2 Test TS Table 3.3.6.2-1 Function 1, Secondary SR 3.3.6.2.4, Channel Calibration, and, Containment and Fuel Building Isolation, SR 3.3.6.2.5, Logic System Functional Reactor Vessel Water Level - Low Low, Test Level 2 TS Table 3.3.7.1 Function 1, Control Room SR 3.3.7.1.4, Channel Calibration, and, Fresh Air System Instrumentation, Reactor SR 3.3.7.1.5, Logic System Functional Vessel Water Level - Low Low, Level 2 Test

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