2CAN029912, Requests Enforcement Discretion from Requirements of TS Table 3.3-1,Action 2 to Allow Startup & Operation of Unit While Exigent TS Is Processed Re Channel D Detector.Encl Documents Util Position Discussed with NRC on 990223

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Requests Enforcement Discretion from Requirements of TS Table 3.3-1,Action 2 to Allow Startup & Operation of Unit While Exigent TS Is Processed Re Channel D Detector.Encl Documents Util Position Discussed with NRC on 990223
ML20207M745
Person / Time
Site: Arkansas Nuclear Entergy icon.png
Issue date: 02/24/1999
From: Vandergrift J
ENTERGY OPERATIONS, INC.
To:
NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
Shared Package
ML20207M748 List:
References
2CAN029912, 2CAN29912, NUDOCS 9903190174
Download: ML20207M745 (11)
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Text

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  • Enttrgy Opir:tisns, Inc.

1448 SR 333 RasseLdc. AR 72601 ic!50185S 5X.

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February 24,1999 2CAN029912 U. S. Nuclear Regulatory Commission Document ControlDesk Mail Station OPI-17 Washington, DC 20555

Subject:

Arkansas Nuclear One-Unit 2 Docket No. 50-368 License No. NPF-6  :

Request For Enforcement Discretion Gentlemen:

l This letter documents the Arkansas Nuclear One, Unit-2 (ANO-2) position (enclosed) discussed on February 23,1999, with members of the Nuclear Regule. tory Commission staff and formally requests enforcement discretion from the requirements of Technical Specification Table 3.3-1, Action 2, to allow startup and operation of the unit while an exigent Technical Specification change is processed to allow startup and continuec, operation with the Reactor Protective System ,

Channel "D" Linear Power Level-High, Logarithmic Power Level-High, and Core Protectio.n Calculator trips on Local Power Density and Departure from Nucleate Beiling Ratio in bypass until a new detector is procured and installed during the ANO-2 Mid-Cycle outage currently scheduled for November 1999. This request also includes discretion from the requirements of Technical Specification 3.0.4 with respect to this issue.

If ANO-2 enters a mode in which the detector can be replaced without creating undue risk to plant personnel and/or equipment before Mid-Cycle Outage 2P99, and a new detector is on site, the Channel "D" execre detector will be replaced at that time.

The enclosed request was reviewed and approved by the ANO Plant Safety Committee at approximately 1820 CST on February 23,1999. Verbal approval of this enforcement discretion request was granted at approximately 2003 CST on February 23,1999. This discretion will be in ,

effect until the staff acts on the proposed technical Specification change requat.

Very truly yours, i

f Jimrpf D. Vander Il Director, Nuclear Safety b

JDV/rhs Enclosure 1NgQG )O 9903190174 990224 "

PDR ADOCK 05000368 3 P

PDR d i

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. U.S.NRC February 24,1999 2CAN029912 Page 2 cci Mr'. Ellis W. Merschoff Regional Administrator U. S. Nuclear Regulatory Commission Region 1V 611 Ryan Plaza Drive, Suite 400 l Arlington, TX 76011-8064 NRC Senior Resident Inspector Arkansas Nuclear One l P.O. Box 310 London, AR72847 Mr. Chris Nolan NRR Project Manager Region IV/ANO-2 U. S. Nuclear Regulatory Commission NRR Mail Stop 13-H-3 One White Flint North 11555 Rockville Pike Rockville, MD 20852 i

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Encl::sure to 1

2CAN009912 Page 1 of 9 REQUEST FOR ENFORCEMENT DISCRETION REGARDING AN INOPERABLE CHANNEL OF EXCORE NUCLEAR INSTRUMENTATION Delcrintkn.of Condition /Reauirements for which Enforcement Discretion is Reauested Applicable Technical Specifications (TS.;

Arkansas Nuclear One - Unit 2 (ANO-2) 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 the Control Element Assembly (CEA) drive system is capable of CEA withdrawal. Action 2 of Table 3.3 1 states, "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 hours5.555556e-4 days <br />0.0133 hours <br />7.936508e-5 weeks <br />1.8264e-5 months <br />, the desirability of maintaining this channel in the bypassed condition shall be reviewed at the next regularly scheduled PSC meeting in accordance with the QA Manual Operations. The channel shall be returned to OPERABLE status prior to startup l following the next COLD SHUTDOWN."  !

LCO 3.0.4 prohibits entry into an operational mode or other specified condition when the i conditions of the limiting condition for operation are not met and the as.ociated action requires a shutdown if they are not met within a specified time interval. Entry into an operational mode or other specified condition may be made in accordance with the action requirement when conformance to them permits continued operation of the facility for an unlimited period of time.

The associated bases explain that LCO 3.0.4 precludes placing the facility in a higher mode of operation when the requirements for a limiting condition for operation are not met and continued noncompliance to these conditions would result in a shutdown to comply with the action requirements if a change in modes were permitted. The purpose of this specification is to ensure that facility operation is not initiated or that higher modes of operation are not entered when correc'.ive action is baing taken to obtain compliance with a specification by restoring equipment to operc.ble status or parameter to specified limits. Coinpliance with action requirements that permit continued operation of the facility for an unlimited period of time provides an acceptable level of safety for continued operation without regard to the status of the plant before or after a mode change. Therefore, in this case, if the requirements for continued operation have been met in accordance with the requirements of the specification, then entiy into that mode of operation is permissible. The provision of this specification should not, however, be interpreted as endorsing the failure to exercise good practice in restoring systems or components to operable status before plant startup.

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Enclosure to I 2CAN029912 Page 2 of 9 Condition Description The ANO-2 excore nuclear instrumentation system includes four safety channels. Each safety

) channel utilizes a fission chamber assembly made up of three detectors which are used to measure the flux in the upper, middle, and lower regions of the core independently. The safety I channels have two ranges: wide range log power (2x104 -200%) and wide range linear power I (0-200%).

Each detector feeds a linear amplifier which provides input to the Reactor Protective System (RPS) CPC trips for LPD - high and DNBR - low. Outputs of the three linear amplifiers (per channel) are also provided to a summer which averagee 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, with ANO-2 operating in Mode 1, the upper detector of the "D" safety channel of excore nuclear instrumentation failed to mio dudng the performance of surveillance l testing. This condition rendered the Channel "D" linear power level - high, 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 ,

I the TS requirements to place the inoperable chanr.el in bypass within one hour. The channel was maintained in bypan 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.

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 tn initial criticality. The replacement detector was subsequently refurbished by the manufacturer. The replacement detector passed all electrical tests prior to installation in l 2R13 and all post installation surveillance tests. The detector was declared operable on February 5,1999.

On February 22,1999, during startup with the unit in Mode 3 and the tdp 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. j I

The ANO-2 TS do not prohibit operation with a channel of RPS in bypass. However, Table  !

3.3-1, Action 2 requires that the inoperable channel be returned to an operable status prior to j startup from the next cold shutdown. Since Channel "D" was inoperable when the unit was

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shutdown for 2R13, the TSs require that it be returned to an operable status prior to restart.

Although Table 3.3-1, Action 2 allows operation with an inoperable channel for an indefinite i period of time and does not contain an explicit shutdown statement, LCO 3.0.4 could be l l

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A Encl:sure to 2CAN029912 Page 3 of 9 interprete'd to prohibit entry into the applicable operational mode since Table 3.3-1, Action 2 requires an inoperable channel to be returned to operable status prior to restart following the next ;

Cold Shutdown. This would require that the Channel "D" excore be replaced prior to entering an ap;;licable mode of operation for the affected functional units.

ANO does not have another 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. Therefore, ANO is requesting 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. Since the safety function of the RPS is unaffected by this request, sufficient time exists to process the j exigent TS change. 1 Criterion for Discretion Approval ,

1 ANO believes that tids request satisfies criterion 3.a of Operations - Notice of Enforcement Discretion (NUREG-1600, Enforcement Policy Section VII C - Exercise of Discretion).

Criterion 3.a states,"The equipment or syvem does not perfor.n a safety function in the mode in which operation is to occur (e.g., a TS which requires the equipment to be operable in a mode not required by the UFSAR)." Channel "D" excore detector is not needed to perform a safety function for startup or power operation. The ANO-2 Safety Analysis Report in Section 7.2 Reactor Protective System describes the function of the RPS. Section 7.2.1.1 System Description notes that "Four measurement channels, wit . electrical and physical separation, are provided for each parameter used in the generation of 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 necd 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 one-out-of-two logic) is that no provision is made to bypass another channel for periodic maintenance. The system logic must be restored to at least a two-out-of-three condition prior to removing another channel for maintenance." In the Safety Evaluation Report (SER) supporting Amen (. ment 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 devi:<s. 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 results 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 concludcd 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 ,

Safety Analysis Report. The Amendment 159 Safety Evaluation Report goes en to conclude that ANO's analyses and tests were performed in accordance with the staff acceptance criteria and m

Enclosure to 2CAN029912 Page 4 of 9 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 (ESh. ).

However, the ptoceding discussion has been determined to be applicable only to the RPS.

Although the excore nuclear instrumentation 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 (Safety Analysis Report and Safety Evaluation Report for Amendment 159) clearly indicates the system is capable of perfonning its safety function with l one channel of RPS inoperable. Therefore, while the technical specification requires the channel l to be returned to OPERABLE status prior to startup following the next COLD SHUTDOWN, the FS AR clearly does not require all four channels of Linear Power Level - High, LPD - High, Log l Power Level - High, CPC and DNBR-Low to be operable in order to startup and operate safely. l i

Two scenarios can be hypothesized to demonstrate that the TS recognize that only three channels  ;

ofRPS are redred to be operable to fulfill the safety function of the system.

Had the "D" excore detector functioned until the unit had completed its startup and then failed, enforcement discretion would not be required. The TS action statement from the previous failure l would have been satisfied with the replacement of the detector even though it only functioned for a short period of time. A new TS action statement would be entered upon the subsequent failure, requiring repair of the detector at the next entry into cold shutdown. l Additionaltv, had a different detector than the "D" excore failed during startup, enforcement i discretion would not have been required because the TS would have allowed startup and i operation until the next cold shutdown.

2 The safety implications of the existing condition for which enforcement discretion is requested is no different then these scenarios, in which the TS allow operation to continue until the next cold shutdown.

Evaluation of SafeN Significance Failure Analysis i

The four safety channels provide neutron flux information from startup neutron flux levels to 200 percent of rated power covering a single range of approximately 2x10 to 200 percent power (10 decades). Each safety channel consists of three fission chambers, a preamplifier and a signal conditioning drawer containing power supplies, a logarithmic amplifier (including combination counting and mean square variation techniques), linear amplifiers, test circuitry and a rate-of-change of power circuit. These channels feed the RPS and provide information for rate-of-change of power display, DNBR, local power density, and overpower protection.

t = - - .

Enclosure to '

' 2CAN029912 Page 5 of 9 1

The details of the sensor input to the signal conditioning equipmen: are shown in ANO-2 SAR Figure 7.2 20. The input Qnals to the core protection calculators are shown in ANO-2 SAR Figure 73-11.

The detector assembly provided for each safety channel consists of three identical fission chambers stacked vertically along the length of the reactor core. The use of multiple tubchannel detectors in this arrangement permits the measurement of axial power shape dunng power operation.

The fission cleambers are mounted in 1: older assemblies which in turn are located in four dry instrument wells (thimbles) in the reactor cavity near the biological shield. The wells ara spaced around the reactor vessel to provide optimum neutron flux information. ,

I Preamplifiers for the fission chambers are mounted outside the biological shield but ins *de the l containment. Physical and electrical separation of the preamplifiers and cabling between channels is provided.

With Channel "D" excore detector inoperable, only three excore detectors will be available. If 1 another detector fails in a non-trip condition or is out of service during surveillance, the remaining two detectors will be capable of detecting unacceptable asymmetric power distributions due to an event and produce a trip.

As discussed in the SER for TS Amendment 159, the CEA ejection accident was the only design and licensing basis event affected by excore response to an asymmetric power distribution. At the time the SER was written, a 10% measurement uncertainty was included 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 of interest 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 fael management techniques have required that the power measurement uncertainty be increased in order to account for the asymmetric power effects of a CEA ejection with one excore detector indefinitely bypassed and an additional detector failed. These power measurement uncertainties are up to 20% in some cases. These uncertainties are included in the CEA ejection analyses for Cycle 14. The Cycle 14 analyses showed no fuel failure would result from a CEA ejection event.

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. Enclosure to 2CAN029912 Page 6 of 9 l Risk Assessment The rlsk resulting from inadvertem 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 rernain .in hypass unless surveillance testing of the other channels of the RPS (i.e., CPCs / i CEACs, high logarithmic power, or high linear power) is required. In these cases, Channel "D" j will be placed in the trip condition and the channel being tested will be placed in bypass. In this configuration, a failure in one of the two remaining channels of RPS will not prevent a reactor trip. However, a failure in one of the two remaining channels of RPS could result in a reactor trip. The rirk associated with a reactor trip is that with additional failures it could lead to core damage.

An assessment of the change in the ANO-2 core damage frequency (CDF) due to perfonning 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.

Engineering Report 97-R-1010-02, Revision 0, "ANO-2 Probabilistic Safety Analysis," reports the frequency of e 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:

CCDP(T6) = 2.449E-06 /1.44 = 1.701E-06 The following assumptions are made in this assessment.

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 start in November 1999. As ofFebruary 23,1999, there are 311 days left in 1999,
2. There are 4 spurious trips of a RPS channel in a year, based upon 11 years of operating data.

The mode the plant was in did not enter into the criterir. Sensor failures were not ccunted since they did not lead to a channel trip.

3. The amount of time in which the system is configured as described above was conservatively assumed to be 1000 hours0.0116 days <br />0.278 hours <br />0.00165 weeks <br />3.805e-4 months <br />.

Br. sed on the assumptions listed above, the number of spu-ious RPS channel trips.during the remaining portion of the cycle is:

(4 trips / yr) * (320 days / 365 days / yr) = 3.507 trips

. Enclasure to 2CAN029912 Page 7 ofP The fraction of time during the remaining portion of the cycle in which testing will be ongoing is:

(1000 hours0.0116 days <br />0.278 hours <br />0.00165 weeks <br />3.805e-4 months <br />) / (320 days

  • 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> / days) = 1.302E-01 Therefcre, the probability of a reactor trip while the system is configured as described above due to a spurious RPS channel trip for the remaining portion of the cycle is:

3.507

  • 1.302E-01 = 4.566E-01 The increased probability of a core damaging event due to a reactor trip as described above for the remaining portion of the cycle is.

1.701E-06

  • 4.566E-01 = 7.77E-07 This change in the CDF due to performing required RPS surveillance testing with the Channel  ;

"D" functions in a trip condition is considered to be non-risk significant using the criteria for i non-risk significance provided it. the PSA Applications Guide -(EPRI TR-1053%, August  ;

1995). j Comnensatory Measures Entergy Operations will follow the requirements of the ANO-2 TS associated with an inoperable "D" excore detector. Additionally, expeditious actions will be taken to acquire a suitable replacement for the inoperable "D" excore detector. The "D" excore detector will be replaced no later than ?he planned mid-cycle outage currently scheduled for November 1999.

Enrineerine Evaluation and Basis For No Sinnificant Hazard Consideration An evaluation of the proposed change has been perforrned in accordance with ICCFR50.91(a)(1) regarding no sigt;ificant hazards considerations using the standards in 10CFR50.92(c). A discunion of these standards as they relate to this enforcement discretion request follows:

Criterion 1 - Does Not Involve a Sinnificant Increase in the Probability or Conseauences of an Accident Previousiv Evaluated.

Start up and operation with the ANO-2 Reactor Protective System (RPS) linear power level -

high and logarithmic power level - high functional units, and the Core 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 mode has no effect on the probability of any accidents previously evaluated as it has no impact on the causes ofinitisdng events in the plant.

Startup and operation with these function 1 unita in a 2-out-of-3 logic mode has no 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 one. This ensures protective

. Enclosure to 2CAN029912 Page 8 of 9 sys' tem actuation in accordance with the assumptions of the accident analysis. The accident analysis has accounted for those events that might have an effect on the functional units due to ,

the geometry of the installed sensors, and demonstrated acceptable results in such a case, l assuming a single failure and a channel in bypass. j l

Therefore, startup and operation with the ANO-2 RPS linear power level - high and logarithmic I power level - high functional units, and the CPC LPD - high, and DNBR - low functional units l in a 2-out-of-3 logic mode does not involve a significant increase in the probability or i consequences of an accident previously evaluated.

Criterion 2 - Does Not Create the Possibility of a New or Different Kind of Accident from any Previousiv Evaluated.

The only way the proposed change could alter the course of an event would be by 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 failing to actuate when required. These functional l units maintain a functional redundancy of one when operating in a 2-out-of-3 logic mode, thus

'he 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 Sinnificant Reduction in the Marnin of Safety.

The ANO-2 technical specification (TS) for RPS linear power level - high and logarithmic power level - high functional units, and the CPC LPD - high, and DNBR - low functional units allows operation through the ruainder of the cycle with only three channels operable, providing that the desirability of maintaining this configuration is reviewed at the next regularly scheduled Plant Safety Committee (PSC) meeting. The TS requires that the inoperable functional unit be returned to operable status prior to startup following the next Cold Shutdown. Per the Safety Evaluation Report for Amendment 159, which added these provisions to the TS, 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 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 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 functional units will provide the protection assumed in the accident analysis.

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-oot-of-3 logic mode does not involve a significant reduction in the margin of safety.

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. Enclosure to 2CAN029912 Page 9 of 9 Based upon the reasoning presented above, Entergy Operations has determined that startup arid 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 consideration.

EnvironmentalImnact Evaluation Entergy Operations, Inc. has reviewed the proposed changes to the Arkansas Nuclear One - Unit 2 (ANO-2) operating license associated with the requested enforcement discretion with respect to their environmentalimpact.

10 CFR 51.22(c) provides criteria for and identification of licensing and regulatory actions eligible for categorical exclusion from performing an environmental assessment. Per 10 CFR 51.27(c)(9), a proposed 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 I exposure. Entergy Operations, Inc. has reviewed the proposed changes to the ANO-2 eperating license and has determined that they meet the eligibility criteria for categorical exclusion set forth in 10 CFR 51.22(c)(9). Pursuant to 10 CFR 51.22(b), no environmental linpact 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:

1. The proposed license amendment does not involve a significant hazards consideration 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 Accident. The proposed license amendment d :s 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 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 retains the required degree of functional redundancy, ensuring the ability of these functional units to function in the event of a single failure.

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