View source for 2CAN029913, Application for Amend to License NPF-6,adding Footnote to Action 2 Allowing Startup with Functional Units Associated with Channel D Excore Inoperable.Action 2 Is Associated with TS Table 3.3-1, Reactor Protective Instrumentation

{{Adams
| number = ML20207C054
| issue date = 02/25/1999
| title = Application for Amend to License NPF-6,adding Footnote to Action 2 Allowing Startup with Functional Units Associated with Channel D Excore Inoperable.Action 2 Is Associated with TS Table 3.3-1, Reactor Protective Instrumentation
| author name = Hutchinson C
| author affiliation = ENTERGY OPERATIONS, INC.
| addressee name = 
| addressee affiliation = NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
| docket = 05000368
| license number = 
| contact person = 
| document report number = 2CAN029913, 2CAN29913, NUDOCS 9903080337
| package number = ML20207C060
| document type = OPERATING LICENSES-APPLIATION TO AMEND-RENEW EXISTING, TEXT-LICENSE APPLICATIONS &amp; PERMITS
| page count = 13
| project = 
| stage = Request
}}

=Text=
{{#Wiki_filter:.         .      _ . _ . _ _           _ _ _     -__ _ _ . .   - . . . . . _ _ _ .         .____ . ~~-             _ _ - . . _ . - _ . _ _ _ . . _ _ _ . _
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Entergy operations,Inc.
h                                                                                                      .AR 72901 T* 501858 4880 I
C. Randy Hutchinson We Presdml Febmary 25,1999                                                                               """
2CAN029913 U. S. Nuclear Regulatory Commission i
Document Control Desk Mail Station OPI-17 Washington, DC 20555                                                                                                                        -
l

==Subject:==
Arkansas Nuclear One - Unit 2 Docket No. 50-368                                                                                                       l License No. NPF-6                                                                                                      :
Proposed Exigent Technical Specification Change Revising Teble 3.3-1 Actions Gentlemen:
Attached for your review and approval is a proposed technical specification (TS) change l
revising Action 2 associated with TS Table 3.3-1, Reactor Protective Instrumentation. The proposed change adds a footnote to Action 2 allowing startup with the functional units                                                      l l-                             associated with the Channel "D" excore inoperable. The proposed footnote only allows this                                                   ;
!                              exception until the startup following the ANO-2 planned mid-cycle outage, 2P99, currently                                                   i scheduled for November 1999.
l On February 23, 1999, Entergy Operations verbally requested enforcement discretion (in l             .
accordance with guidance contained in NUREG-1600, " Enforcement Policy Section VII C -
Exercise of Discretion,") from the requirements of TS limiting condition for operation (LCO) 3.0.4 and Table 3.3-1, Action 2, with respect to startmg up with an inoperable excore detector. The NRC verbally granted the requested enforcement discretion at approximately 2002 CST on February 23,1999. Entergy Operations formally documented the requested enforcement discretion by {{letter dated|date=February 24, 1999|text=letter dated February 24,1999}} (2CAN029912).
s NUREG-1600, " Enforcement Policy Section VII C - Exercise of Discretion," requires that follow-up license amendments for NRR-issued notices of enforcement discretion (NCEDs) be processed on an exigent basis in accordance with'the process for exigent amendments.
,                             NUREG-1600 also requires the licensee to submit the follow-up license amendment within 48 hours of the oral request. This submittal satisfies this requirement.
i                             Entergy , Operations requests that this proposed change be considered under exigent l                             circumstances as described in 10 CFR 50.91(a)(6) in that failure to act quickly could prevent
!                              startup from the next cold shutdown if a replacement excore is not available on site. As                                                    ;
required by 10 CFR 50.91(a)(6), a statement of the exigent circumstances surrounding this
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l       i     U. S. NRC February 25,1999 2CAN029913 Page 2 request is attached. Entergy Operations requests that the effective date for this change be inuhediately upon issuance.
The proposed change has been evaluated in accordance with 10CFR50.91(a)(1) using criteria in 10CFRSO.92(c) and it has been determined that this change involves no significant hazards considerations. The bases for these determinations are included in the attached submittal.
I l             Very truly your                     _ ///
                                                             ._'            s                                                        i
                .RH/cws                                                                                                              j Attachments To the best of my knowledge and belief, the statements contained in this submittal are true.
SUBSCRIBED AND SWORN TO before me, a Notary Public in and for                                           &
County and the State of Arkansas, thisJ5" day of Mh ,1998. '
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J. U. S. NRC                                                                    j
               . February 25,1999 2CAN029913 Page 3 cc:'   Mr. Ellis W. Merschoff                                                I Regional Administrator t                      U. S. Nuclear Regulatory Commission
                      - Region IV 611 Ryan Plaza Drive, Suite 400 Arlington, TX 76011-8064 NRC Senior Resident Inspector Arkansas Nuclear One
                      . P.O. Box 310 -
London, AR 72847                                                      ,
l
                      .Mr. Chris Nolan                                                       I NRR Project Manager Region IV/ANO-2 U. S. Nuclear Regulatory Commission NRR Mail Stop 13-H-3 One White Flinc North                                                 !
11555 Rockville Pike                                                 i Rockville, MD 20852                                                  1 l
Mr. David D. Snellings;                                              l Director, Division ofRadiation                                        1 Control and Emergency Management                                   I
!                      Arkansas Department ofHealth                                          j 4815 West Markham Street                                              <
!                      Little Rock, AR 72205                                                 )
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l      .                                                                               i ATTACHMENT                                   i
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l TD                                     i 2CAN029913 PROPOSED TECHNICAL SPECIFICATION                          j
                                                                                     .i AND                                     j RESPECTIVE SAFETY ANALYSES IN THE MATTER OF AMENDING LICENSE NO. NPF-6 ENTERGY OPERATIONS. INC.                           .
i l
ARKANSAS NUCLEAR ONE. UNIT TWO DOCKET NO. 50-368 l
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i    Attachm:nt to 2CAN029913 l'Page1of9  .
DESCRIPTION OF PROPOSED CIIANGES Arkansas Nue: ear One - Unit 2 (ANO-2) technical specification (TS) Table 3.3-1 requires that three of four channels of the linear power level - high, local power density - high (LPD -
high), departure from nucleate boiling ratio - low (DNBR - low) and core protection calculator (CPC) functions be operable in Modes 1 and 2, that three of four channels of the
)             logarithmic power level - high function be operable in Mode 2 and in Modes 3,4, and 5 when
     \       the protective system trip breakers are closed and t% control element assembly (CEA) drive system is capable of CEA withdrawal. Action 2 of Table 3.3-1 *tates, "With the number of channels OPERABLE one less than the Total Number of Channels, operation in the applicable
]           MODES may continue provided the inoperable channel is placed in the bypassed or tripped condition within I hour. If the inoperable channel is bypassed for greater than 48 hours, the desirability of maintsining this channel in the bypassed condition shall be reviewed at the next g           regularly scheduled PSC meeting in accordance with the QA Manual Operations. The channel shall be returned to OPERABLE status prior to startup following the next COLD SHUTDOWN."
g           TS Table 3.3-1, Action 2, has been revised by the addition of a footnote. The footnote allows
]           ANO-2 to startup with the functional units associated with the Channel "D" excore                 '
inoperable. These functional units are: linear power level - high (functional unit 2);
g logarithmic power level - high (functional unit 3a); locd power density - high (functional unit l-9); departure from nucleate boiling ratio - low (functional unit 10); and core protrtion calenlators (functional unit 14). The footnote also limits this exception to startups prio .o the mid-cycle outage,2P99, currently scheduled for November 1999.                                     '
p           BACKGROUND q.g         The ANO-2 excore nuclear instmmentation system, as described in ANO-2 Safety Analysis Report (SAR) Section 7.2.1.1.2.3, includes four safety channels. Each safety channel utilizes f          a fission chamber assembly made up of three detectors which are ud to measure the flux in the uppr, middle, and lower regions of the core independently. The safety channels have two ranges: wide range log power (2x10t200%) and wide range linear power (0-200%).
Each detector feeds a linear amplifier which provides input 16 the reactor protective system (RPS) CPC trips for LPD - high and DNBR - low. The RPS is described in ANO-2 SAR n .       Section 7.2. Outputs of the three linear amplifiers (per channel) are also provided to a summer which averages the signals and provides input to the linear power level - high trip.
The center detector also inputs to the logarithmic power circuitry which inputs to the logarithmic power - high trip.
On November 3,1998, vi ANO-2 operating in Mode 1, the upper detector of the "D" safety channel of excore nuclear instrumentation failed to zero during the performance of smveillance testing. This condition rendered the Channel "D" linear power level - high, Channel "D" CPC, LPD - high, and DNBR - low functions inoperable.
m

i           - Attachment to                                                                                                    r 2CAN029913
['                       Page 2 of 9 l^
RPS Channel "D" was in bypass for testing at the time of the detector failure, thereby                           '
satisfying the TS requirements to place the inoperable channel in bypass within one hour. The l                        channel was maintained in bypass or trip until the unit was shutdown for Refueling Outage
!                      ' 2R13 on January 9,1999. This configuration was reviewed and approved by the Plant Safety Committee (PSC) on November 4,1998.
L                        During early February 1999, the Channel "D"' detector assembly was replaced with a spare
!                        detector assembly. The replacement detector was originally installed in the plant but was                        ;
!                        removed prior to initial criticality. The replacement detector was subsequently refurbished by the manufacturer. The replacement detector passed all electrical tests prior to installation and
!                        all post installation surveillance tests.'                     The detector _ was declared operable on l                        February 5,1999.
On February 22,1999, during startup with the unit in Mode 3 and the trip breakers closed, the Control Board Operator identified that the Channel "D" logarithmic power channel was reading approximately one decade higher than the other channels. Channel "D" logarithmic power was placed in bypass in accordance with the TS. Subsequent troubleshooting identified
                      . that the center detector or associated cables for the Channel"D" excore assembly was faulty.                      ,
l l                        ANO does not have another new or refurbished spare detector assembly on site and there are no r milar detectors available. Initial discussions with the detector vendor indicate that the                   .
lead time for procuring a new detector is greater than two months. Therefore, ANO verbally requested enforcement discretion regarding TS LCO 3.0.4 and Table 3.3-1, Action 2, to allow startup of the unit while an exigent TS change is processed to allow startup and continued operation with the functional units associated with the Channel "D" excore in bypass until a new detector is procured and installed during the ANO-2 Mid-Cycle _ outage currently scheduled for November 1999. This enforcement discretion 'was verbally requested by                              l Entergy Operations on February 23, 1999. The NRC verbally granted the requested enforcement discretion at approximately 2002 CST on February 23, 1999. Entergy Operations formally documented the requested enforcement discretion by {{letter dated|date=February 24, 1999|text=letter dated February 24,1999}} (2CAN029912).
l Operation of the RPS in a 2-out-of-3 logic with the fourth channel placed in indefinite bypass was reviewed and approved by the NRC in a Safety Evaluation Report (SER) for ANO-2 Amendment 159, dated April 3,1995.
DISCUSSION OF CHAN,CE The ANO-2 SAR, in Section 7.2, " Reactor Protective System," describes the function of the i                        RPS. Section 7.2.1.1, " System Description," notes that "Four measurement channels, with electrical and physical separation, are provided for each parameter used in the generation of l                     - trip signals... A 2-out-of-4 coincidence oflike trip signals is required to generate a reactor
;                        trip signal. These same features include the capability of the RPS to operate, if need be, with up to two channels out of service (one bypassed and another tripped) and still meet the single
[                       failure criteria. The only operating restriction while in this condition (effectively 1-out-of-2 i
5

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Attachment to 2CAN029913 Page 3 of 9 logic)is that no provision is made to bypass another channel for periodic maintenance. The
            ' system logic must be restored to at least a 2-out-of-3 condition prior to removing another channel for maintenance." In the SER supporting Amendment 159 to the ANO-2 Technical Specifications it is noted: "In addition, the licensee submitted an updated ' Failure Modes and Effect Analysis (FMEA)' which is currently part of the ANO-2 FSAR and addresses failures in the PPS system from the sensors to the activation devices. The FMEA also addresses failures of the power supplies to the PPS. This analysis was performed to demonstrate defense against single failure with one of the four PPS channels in a bypass condition. The resuts of this analysis shows that with one channel in bypass, no single failure in the remaining channels will prevent the PPS from performing its safety function. Therefore, based on the matrix relay design, operating history, and test results, the licensee concluded that a single bus failure would not cause multiple failures of the matrix trip relays and would not prevent the PPS from performing its protection function with a single PPS trip channel in bypass." The above referenced FMEA table is Table 7.2-5 in the ANO-2 SAR. The Amendment 159 SER goes on to conclude that ANO's analyses and tests were performed in accordance with the Staff aceptance criteria ad adequately demonstrated that: "With one channel in bypass and a second channel subject to a single failure, the PPS will provide the protection functions required by the accident analysis. .With one PPS protection channel in bypass, no credible single failure of a vital bus could be identified to affect the six matrix trip relays and jeopardize the actuation of PPS." The PPS consists of the RPS and the Engineered Safety Feature Actuation System (ESFAS). 'However, the preceding discussion is applicable only to the RPS.
Although the excore nuclear instmmentation system does provide a safety function at power, bypassing one channel does not prevent fulfillment ofits intended safety function as discussed above. The ANO-2 licensing basis (SAR and the SER for Amendment 159) clearly indicates the system is caoable of performing its safety function with one channel of RPS inoperable.
Therefore, while the technical specification requires the channel to be returned to operable status prior to startup following the next cold shutdown, the SAR clearly does not require all four channels of linear power level - high, LPD - high, log power level - high, CPC and l            DNBR-Low to be operable in order to startup and operate.
l            As discussed in the SER for TS Amendment 159, the CEA ejection acciden was the only design and licensing basis event affected by excore response to an asymmetric power l            distribution. At the time the SER was written, a 10% measurement uncertainty was included l            in the analyses of that event to conservatively account for power asymmetry effects on the excore detectors for any ejected CEA. A review of the ANO-2 SAR Chapter 15 events showed that CEA ejection and asymmetric steam generator transient (ASGT) are the events
;            ofinterest with respect to asymmetric power profile An ASGT trip will be initiated on high differential temperature between the cold legs associated with the two steam generators and does not credit the output from the excore detectors to trip the unit. CEA ejection relies on the excore detectors to provide the required reactor trip.
Recent core designs using more aggressive fuel management techniques have required that the power measurement uncertainty be increased in order to account for the asymmetric power

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Attachment to 2CAN029913
,                       Page 4 of 9                                                                                           1 l
l                       effects of a CEA ejection with one excore detector indefinitely bypassed and an additional            I l               '
detector failed. These power measurement uncertainties are up to 20% in some cases. These uncenaimies are included in the CEA ejection analyses for Cycle 14. The Cycle 14 analyses showed no fuel failure would result from SAR Chapter 15 CEA ejection event.
                    . The risk resulting from inadvertent plant trips associated with placing the RPS functional units
:                       associated with Channel "D" excore into indefinite bypass for the first half of Cycle 14 (from initial criticality to the mid-cycle outage in November 1999) was evaluated. Channel "D" will remain in bypass unless surveillance testing of the other channels of the RPS is in progress. In these cases, Channel "D" will be placed in the trip condition and the channel being tested will       i be placed in bypass. In this configuration, a failure in one of the two remaining channels of         I RPS will not prevent a reactor trip. However, a failure m one of the two remaining channels l                       ofRPS could result in a reactor trip.
l                       An assessment of the change in the ANO-2 core damage frequency (CDF) due to performing                i i                       the required testing of the remaining RPS channels with the Channel"D" functions in a trip            !
!                       condition was performed. A summary of the assessment is provided below.                               l l
Engineering Report 97-R-1010-02, Revision 0, "ANO-2 Probabilistic Safety Analysis,"
reports the frequency of a reactor trip (initiating event T6) to be 1.44 trips per reactor year.
This report also states the CDF associated with a reactor trip (T6) is 2.449E-06 per reactor year. The conditional core damage probability (CCDP) given a reactor trip is the ratio of the CDF given a reactor trip and the reactor trip frequency. Therefore i
CCDP(T6) = 2.449E-06 /1.44 = 1.701E-06
                                                                                                                              ]
l The following assumptions are made in this assessment.
i 1
: 1. The duration of this scenario is assumed to be 320 days. This conservatively bounds the time from February 23, 1999, until the start of 2P99, currently scheduled to stan in November 1999. As ofFebruary 23,1999, there are 311 days left in 1999.
l                       2. There are 4 spurious trips of a RPS channel in a year, based upon 11 years of operating l                             data. The mode the plant was in did not enter into the criteria. Sensor failures were not counted since they did not lead to a channel trip.
l
: 3. The amour.t of time in which the cystem is configured as described above was L                             conservatively assumed to be 1000 hours.
l
!                       Based on the assumptions listed above, the number of spurious RPS channel trips during the remaining portion of the cycle is:
(4 trips / yr) * (320 days / 365 days / yr) = 3.507 trips L                                                                                                                           l
 ;                                                                                                                            1 4
s 0

ft                                                                                                                              i f, '          i        Attachment to                                                                                            !
      ?*               2CAN029913'
                    " Pagi 5 of 9 ;                                                                                             i
!                                            .        .                                                                         I The fraction of time durit the remaining portion of the cycle in which testing will be ongoing           )
is:"    >
l
                                 .         (1000 hos A / (320 days
* 24 hours / days) = 1.302E-01 l                    .Therefore, the probability of a reactor trip while the system is configured as described above I                      due to a spurious RPS channel trip for the remaining portion of the cycle is:                             !
L,                                                      3.507
* 1.302E-01 = 4.566E-01 l
The increased probability of a core damaging event due to a reactor trip as described above p                      for the remaining portion of the cycle is:
l.
!                                                      1.701E-06
* 4.566E-01 =.7.77E-07 1-l This change in the CDF due to performing required FPS surveillance testing with the Channel              l l                      "D" functions in a trip condition is considered to be non-risk significant using the criteria for         l l                      non-risk' significance provided in the PSA Applications Guide (EPRI TR-105396, August 1995).                                                                                                   ,
Reviews and evaluations performed in conjunction with the review and approval of-Amendment 159 have shown that operation for an indefinite period of time with one channel i
of RPS bypassed is acceptable. The excore neutron instmmentation retains the ability to
: j.                     detect a CEA ejection with one channel inoperable and an additional single failure, using conservative assumptions. During surveillance testing of other RPS channels, Channel "D"
,                     will be placed in the trip condition and the channel being tested will be placed in bypass. In L                      this configuration, a failure in one of the two remaining channels of RPS will not prevent a
!                      reactor trip. While in this configuration, should a failure in one of the two remaining channels          ;
of RPS result in a reactor trip, the change in CDF has been shown to be non-risk significant.             i Therefore, the proposed change is acceptable.
1 L                      STATEMENT OF EXIGENT CIRCUMSTANCES i
l 10 CFR 50.91(a)(6) states that whenever an exigent condition exists, a licensee requesting an            l amendment must expl h why this exigent situation occurred and why it could not be avoided.
L                      On November 3,1998, with ANO-2 operating in Mode 1, the upper detector of the "D" l                      safety channel of excore nuclear instrumentation ~ failed to zero during the performance of
!~                   - surveillance' testing. This condition rendered the Channel "D" linear power level - high, L                      Channel "D" CPC, LPD - high, and DNBR - low functions inoperable.
                     ' RPS Channel "D" was in bypass for testing at the time of the detector failure, thereby satisfying the TS requirements to place the inoperable channel in bypass within one hour. The
 ;                     channel was maintained in bypass or trip until the unit was shutdown for Refueling Outage L
             . .-    -. ..                     -           -          ..-       -    -=    .                      - -.   - .- -

i            Attachment to                                                                                              i 2CAN029913                                                                                                 !
Page 6 of 9                                                                                                I L                    2R13 on January 9,1999. This configuration was reviewed and approved by the Plant Safety l                 -
                    " Committee (PSC) on November 4,1998.
i l
During early February 1999, the Channel "D" detector assembly was replaced with a spare                    l detector assembly. The replacement detector was originally installed in the plant but was removed prior to initial criticality and subsequently refurbished by the manufacturer. The replacement detector passed all electrical tests prior to installation and all post installation           '
surveillance tests. The detector was declared operable on February 5,1999.
On February 22, l'999, during startup with the unit in Mode 3 and the trip breakers cles-d, the Control Board Operator. identified that the Channel "D" logarithmic power channel was reading approximately one decade higher than the other channels. Channel "D" logarithmic -
l l                    power was placed in bypass in accordance with the TS. Subsequent troubleshooting identified that the center detector or associated cables for the Channel "D" excore assembly was faulty, 1
ANO does not have another new or refurbished spare detector assembly on site and there are no similar detectors available. Initial discussions with the detector vendor indicate that the lead time for procuring a new detector is greater than two months. Without this proposed TS
: l.                   change, the ability of ANO-2 to return to full power operation following an entry into cold I                    shutdown will be impacted if the postulated cold shutdown occurs before a replacement excore detector is'available. -Therefore, Entergy Operations requests that this proposed
!                    technical specification change be considered under exigent circumstances as described in
!                     10 CFR 50.91(a)(6).
DETERMINATION OF NO SIGNIFICANT HAZARDS CONSIDERATION                                            '
Entergy Operations, Inc. is proposing that the Arkansas Nucleu One Unit 2 (ANO-2)                          3 l                    Operating License be amended to allow startup from cold shutdown with the technical specification Table 3.3-1, " Reactor Protective Instruments," functional units associated with the Channel "D" excore not restored to operable status until the startup following the planned mid-cycle outage (2P99).
[
I                    An evaluation of 'the proposed change has been performed in accordance with l                     10CFR50.91(a)(1) regarding no significant hazards considerations using the standards in
: l.                    10CFR50.92(c). A discussion of these standards as they relate to this' amendment request
                    - follows:
Criterion 1 -        Does Not Involve a Significant Increase in the Probability or Consequences of an Accident Previously Evaluated.
                                                                                                                                )
g                             Startup and operation with the ANO-2 Reactor Protective System (RPS) linear power
,                            level - high and logarithmic power level - high functional units, and the Core l                            Protection Calculator (CPC) local power density - high (LPD - high), and departure from nucleate boiling ratio - low (DNBR - low) functional units in a 2-out-of-3 logic 1 -
4 4
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[          i                   - Attachment to 2CAN029913 L*
L*                                Page 7 of 9 -                                                                                                     i i                                                                                                                                                  l L                                         mode has no effect on the probability of any accidente previously evaluated as it has no l
impact on tha causes ofinitiating events in the plant.
L l                                         Startup and operation with these functional units in a 2-out-of-3 logic mode has no                      I i                                         effect on the consequences of an event previously evaluated since, with one channel of each functional unit in bypass, the functional units maintain a functional redundancy of                 i
                                        . one. This ensures protective system actuation in accordance with the assumptions of                      3
                                        . the accident analysis. The accident analysis has accounted for thosc events that might                  1
                                        > have an effect on the functional units due to the geometry of the installed sensors, and '
,                                         demonstrated acceptable results in such a case, assuming a single failure and a channel L                                         in bypass.                                                                                                l l                                         Therefore, startup and operation with the ANO-2 RPS linear power level -' high'and
!                                         logarithmic power level- high functional units, and the CPC LPD - high, and DNBR -
l                                         low functional units in a 2-out-of-3 logic mode does not involve a significant increase L                                         in the probability or consequences of an accident previously evaluated.
l l-                                        Criterion 2 -         Does Not Create the Possibility of a New or Different Kind of Accident from any Previously Evaluated.
The only way the proposed change could alter the course of an event would be by the                       ,
i-                                        ANO-2 RPS linear power level - high and logarithmic power level - high functional                        !
L                                         units, and the CPC LPD - high, and DNBR - low functional units failing to actuate                        I l
when required. These functional units maintain a functional redundancy of one when operating in a 2-out-of-3 logic mode, thus the functional units will not fail in this
,                                         manner.
Therefore, startup and operation with the ANO-2 RPS linear power level - high and logarithmic power level- high functional units, and the CPC LPD - high, and DNBR -                        ,
low functional units in a 2-out-of-3 logic mode does not create the possibility of a new                  !
or different kind of accident from any previously evaluated.
Criterion 3 -         Does Not Involve a Significant Reduction in the Margin of Safety.
The ANO-2 technical specification (TS) for RPS linear power level - high and L                                         logarithmic power level - high functional units, and the CPC LPD - high, and DNBR -                       l l                                         low functional units allows operation through the remainder of the cycle with ordy                        l
: l.                                      :three channels operable, providing that the desirability of maintaining this i                                         configuration is reviewed at the next regularly scheduled Plant Safety Committee                         '
                                        '(PSC) meeting. The TS requires that the inoperable functional unit be returned to i:                                        operable status prior to startup following the next Cold Shutdown. Per the Safety
[
1 Evaluation Report for TS Amendment 159, which added these provisions to the TS, 1
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    .                     Attachmsnt to i*                        2CAN029913 .                                                                                                 [
l                         Page 8 of 9 the goal of the PSC review and the requirement to return the system to an operable status prior to startup was to repair the inoperable channel and return it to service as           -
quickly as practical. Review of the design and installation of these functional units L                                   has demonstrated that, while starting up or operating in a 2-out-of-3 logic mode, their
                                  . functional redundancy is one. For any design bases event, with the occurrence of any l
L                                   postulated single failure, the ANO-2 RPS linear power level - high and logarithmic power level - high functional units, and the CPC LPD - high, and DNBR - low i                                   functional units will provide the protection assumed in the accident analysis.
Therefore, startup an.d operation with the ANO-2 RPS linear power level - high and logarithmic power level- high functional units, and the CPC LPD - high, and DNBR - -               ,
low functional units in a 2-out-of-3 logic mode does not involve a significant reduction           i in the margin of safety.
Based upon the reasoning presented above, Entergy Operations has determined that                   -
startup and operation with the ANO-2 RPS linear power level- high and logarithmic power level - high functional units,~ and the CPC LPD - high, and DNBR - low functional units in a 2-out-of-3 logic mode does not involve a significant hazards y                                   consideration.
There# ore, based upon the reasoning presented above and the previous discussion of the ann.ndment request, Entergy Operations has determined that the requested change does og                      .
involve a significant hazards consideration.
B ENVIRONMENTAL IMPACT EVALUATION l.
                       .10 CFR 51.22(c) provides criteria for and identification oflicensing and regulatory actions
;                         eligible for categorical exclusion from performing an environmental assessment. A proposed l                         amendment to an operating license for a facility requires no environmental assessment if operation of the facility in accordance with the proposed amendment would not: (1) involve a significant hazards consideration, (2) result in a significant change in the types or significant increase in the amounts of any effluents that may be released off-site, or (3) result in a significant increase in individual or cumulative occupational radiation exposure. Entergy Operations, Inc. has reviewed this license amendment and has determined that it meets the eligibility criteria for categorical exclusion set forth in 10 CFR 51.22(c)(9). Pursuant to 10 CFR 51.22(b), no environmental impact statement or environmental assessment need be prepared in connection with the issuance of the proposed license amendment. The basis for this determination is as follows:
l                          1.       The proposed license amendment does not involve a significant hazards consideration L                                   as described previously in the evaluation.
: 2.        As discussed in the significant hazards evaluation, this change does not result in a significant change or significant increase in the radiological doses for any Design Basis

1
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          !   2CAN029913                                                                                       i
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Page 9 of 9                                                                                     )
Accident. The proposed license amendment does not result in a significant change in the types or a significant increase in the amounts of any effluents that may be released off-site.
: 3. The proposed license amendment does not result in a significant increase to the           !
individual or cumulative occupational radiation exposure because startup and              i operation with the ANO-2 RPS linear power level- high and logarithmic power level
                     - high functional units, and the CPC LPD - high, and DNBR - low functional units in a     i 2-out-of-3 logic mode retains the required degree of functional redundancy, ensuring      l the ability of these functional units to function in the even: ef a single failure.
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