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Revision as of 06:41, 3 April 2018

Millstone Power Station, Unit 3, Response to Request for Additional Information Regarding Relocation of Specific Surveillance Frequency Requirements to a Licensee Controlled Program (TAC No. ME9733)
ML13008A328
Person / Time
Site: Millstone Dominion icon.png
Issue date: 01/04/2013
From: Price J A
Dominion, Dominion Nuclear Connecticut
To:
Document Control Desk, Office of Nuclear Reactor Regulation
References
TAC ME9733
Download: ML13008A328 (16)


Text

Dominion Nuclear Connecticut, Inc.5000 Dominion Boulevard, Glen Allen, VA 23060 omIInionWeb Address: www.dom.com January 4, 2013U. S. Nuclear Regulatory Commission Serial No. 12-764Attention: Document Control Desk NSSLNVDC ROWashington, DC 20555 Docket No. 50-423License No. NPF-49DOMINION NUCLEAR CONNECTICUT, INC.MILLSTONE POWER STATION UNIT 3RESPONSE TO REQUEST FOR ADDITIONAL INFORMATION REGARDINGRELOCATION OF SPECIFIC SURVEILLANCE FREQUENCY REQUIREMENTS TO ALICENSEE CONTROLLED PROGRAM (TAC NO. ME9733)By letter dated October 4, 2012, Dominion Nuclear Connecticut, Inc. (DNC) submitted alicense amendment request (LAR) for Millstone Power Station Unit 3 (MPS3). Theproposed amendment would relocate certain technical specification (TS) surveillancefrequencies to a licensee controlled program by adopting Technical Specification TaskForce (TSTF)-425, Revision 3, "Relocate Surveillance Frequencies to Licensee Control-RITSTF [Risk-Informed Technical Specification Task Force Initiative] 5b." Theproposed change would also add a new program, the Surveillance Frequency ControlProgram, to the TSs, in accordance with TSTF-425. TSTF-425 is approved for use bythe Nuclear Regulatory Commission (NRC). In a letter dated December 18, 2012, theNRC transmitted a request for additional information (RAI) to DNC related to the LAR.DNC agreed to respond to the RAI by January 31, 2013.Attachment 1 provides DNC's response to the NRC's RAI with the exception ofQuestion 3, which will be addressed by January 31, 2013. Attachment 2 provides themarked-up TS page.If you have any questions regarding this submittal, please contact Wanda Craft at (804)273-4687.Sincerely,J.PriceVice President -Nuclear EngineeringCOMMONWEALTH OF VIRGINIACOUNTY OF HENRICOThe foregoing document was acknowledged before me, in and for the County and Commonwealth aforesaid, today byJ. Alan Price, who is Vice President -Nuclear Engineering of Dominion Nuclear Connecticut, Inc. He has affirmedbefore me that he is duly authorized to execute and file the foregoing document in behalf of that company, and that thestatements in the document are true to the best of his kn ledge and belief.Acknowledged before me this day of ,2013.My Commission Expires: 4. ,, Cx NOTARY PLy OREGISTRATIONWAý014, zg /I _0M--.....-.-7*N~oitaryElic .---

Serial No. 12-764Docket No. 50-423Page 2 of 2Attachments:1. Response to Request for Additional Information Regarding Relocation of SpecificSurveillance Frequency Requirements to a Licensee Controlled Program2. Marked-up Technical Specifications PageCommitments made in this letter: Nonecc: U.S: Nuclear Regulatory CommissionRegion I2100 Renaissance BlvdSuite 100King of Prussia, PA 19406-2713J. S. KimProject Manager -Millstone Power StationU.S. Nuclear Regulatory Commission'One White Flint North11555 Rockville PikeMail Stop 08-C2ARockville, MD 20852-2738NRC Senior Resident InspectorMillstone Power Station Serial No. 12-764Docket No. 50-423ATTACHMENT 1RESPONSE TO REQUEST FOR ADDITIONAL INFORMATION REGARDINGRELOCATION OF SPECIFIC SURVEILLANCE FREQUENCYREQUIREMENTS TO A LICENSEE CONTROLLED PROGRAMDOMINION NUCLEAR CONNECTICUT, INC.MILLSTONE POWER STATION UNIT 3 Serial No. 12-764Docket No. 50-423Attachment 1, Page 1 of 11By letter dated October 4, 2012, Dominion Nuclear Connecticut, Inc. (DNC) submitted alicense amendment request (LAR) for Millstone Power Station Unit 3 (MPS3). Theproposed amendment would relocate certain technical specification (TS) surveillancefrequencies to a licensee controlled program by adopting Technical Specification TaskForce (TSTF)-425, Revision 3, "Relocate Surveillance Frequencies to Licensee Control-RITSTF [Risk-Informed Technical Specification Task Force Initiative] 5b." Theproposed change would also add a new program, the Surveillance Frequency ControlProgram (SFCP), to the TSs, in accordance with TSTF-425. TSTF-425 is approved foruse by the Nuclear Regulatory Commission (NRC). In a letter dated December 18,2012, the NRC transmitted a request for additional information (RAI) to DNC related tothe LAR. This attachment provides DNC's response to the NRC's RAI, with theexception of Question 3.Question IThe submittal does not identify that technical specification (TS) Bases are adoptedconsistent with the U.S. Nuclear Regulatory Commission (NRC) letter issued April 14,2010 Agencywide Documents Access and Management System (Accession NumberML100990099) subsequent to the adoption of (Technical Specification Task Force)TSTF-425. In addition, the submittal's "Insert #2" is not consistent with this letter.Please provide confirmation that the TS Bases will be adopted consistent with this letter.DNC ResponseIn the original issuance of TSTF-425, the TS Bases insert read as follows:"The Surveillance Frequency is based on operating experience, equipment reliability,and plant risk and is controlled under the Surveillance Frequency Control Program."Several licensees submitting LARs for adoption of TSTF-425 identified a need todeviate from this statement because it only applies to frequencies that have beenchanged in accordance with the SFCP and does not apply to frequencies that arerelocated but not changed.In NRC letter dated April 14, 2010, the NRC staff agreed that the TSTF-425 TS Basesinsert applies to surveillance frequencies that are relocated and subsequently evaluatedand changed, in accordance with the SFCP. The TSTF-425 TS Bases does not applyto surveillance frequencies relocated to the SFCP but not changed. Therefore, forsurveillance frequencies relocated to the SFCP but not changed, existing plant-specificTS Bases descriptions remain valid for the unchanged surveillance frequency.In a subsequent discussion on April 28, 2012 between the TSTF and the NRC, the NRCstaff supported the following recommended changes :

Serial No. 12-764Docket No. 50-423Attachment 1, Page 2 of 111. The existing Bases information describing the basis for the surveillancefrequencies will be relocated to the licensee-controlled SFCP.2. The TSTF-425 TS Bases, INSERT #2, will be changed to read as follows:"The Surveillance Frequency is controlled under the Surveillance FrequencyControl Program."In response to this issue, a note was added to the insert section of TSTF-425-A, Rev. 3.The note reads as follows:NOTE: The NRC and TSTF recommend a change to the Insert 2 wording and the NRCaccepts it as an acceptable deviation from the Traveler. After the "OR" and before the"Reviewer's Note," the recommended wording is, "The Surveillance Frequency iscontrolled under the Surveillance Frequency Control Program."Additionally, this change has been incorporated into Revision 4 of NUREG 1431,Standard Technical Specifications for Westinghouse Plants.Consistent with these actions, DNC incorporated the recommended changes into thisLAR.Question 2Please discuss how the focused peer review met the peer review guidance in theAmerican Society of Mechanical Engineers (ASME) standard ANS[American NuclearSociety] RA-Sa-2009 and the clarifications in Regulatory Guide 1.200.DNC ResponseThe focused peer review was performed by a diverse team of consultants from ScienceApplications International Corporation (SAIC) with individual experience ranging from 24to 32 years in the nuclear industry. SAIC met the peer review team composition andpersonnel qualifications outlined in Section 1-6.2 of the ASME/ANS Probabilistic RiskAssessment (PRA) Standard RA-Sa-2009.In addition, SAIC stated in their final report, "The purpose of this report is to documentthe final results of the focused scope Peer Review of the Millstone Power Station Unit 3(MPS3) Probabilistic Risk Assessment (PRA) against the requirements of the AmericanSociety of Mechanical Engineers (ASME)/American Nuclear Society (ANS) PRAstandard and any Clarifications and Qualifications provided in the Nuclear RegulatoryCommission (NRC) endorsement of the Standard contained in Revision 2 to RegulatoryGuide (RG) 1.200. This peer review was performed using .the process defined inNuclear Energy Institute (NEI) 05-04."

Serial No. 12-764Docket No. 50-423Attachment 1, Page 3 of 11Question 4Gap #1. Please clarify if the interviews with plant personnel were to determine ifpotential initiating events have been overlooked. If not, describe the steps to addressthis supporting requirement.DNC ResponseSince documentation of the interviews was not retained, specific record of the questionsasked is not available. A recent interview between PRA staff and Operations validatedthat potential initiating events have been identified, which satisfies the requirements ofSR IE-A8.As stated in the October 4, 2012 submittal, a process has been developed andimplemented to document discussions with plant personnel. Guidance and ReferenceDocumentation (GARD) NF-AA-PRA-101-2011, Initiating Event Identification andGrouping, provides instructions for interviewing plant personnel (e.g., Operations,Maintenance, Engineering) including identification of potential initiating events and pastoperating experience. As additional interviews with plant personnel are completed, theinformation will be documented in the PRA notebooks.Question 5Gap #2. The disposition of this supporting requirements states this is a documentationissue only; however, no discussion is provided on the plant walkdowns and interviewsmentioned in the supporting requirement. Please discuss these walkdowns andinterviews which address this supporting requirement (SR).DNC ResponseAs stated in the October 4, 2012 submittal, a process has been developed andimplemented to document information on plant walkdowns and discussions with plantpersonnel.- Documentation of plant walkdowns and interviews are now maintained inthe PRA system notebooks. Plant walkdowns and interviews with knowledgeable plantpersonnel are conducted as described in GARD NF-AA-PRA-101-2040, SystemsAnalysis and Fault Tree Model Development, to confirm system analysis correctlyreflects the as-built, as-operated plantQuestion 6Gap #3 and #4. The submittal notes that human reliability analysis (HR) SRs[supporting requirements] HR-G5 and HR-G7 were met, however, an F&O [findings andobservations] was' written for the SRs based on nonsystematic discrepancies that the Serial No.12-764'Docket No. 50-423Attachment 1, Page 4 of 11PRA peer review team judged to require correction. Please correct the impactedhuman error probabilities.DNC ResponseGap #3 (HR-G5) is based on outdated (circa 2006) talk-through documentation withOperations. Operator survey information has not been updated to support the basis forrevised or new human failure events (HFEs). Therefore, a bounding sensitivity studywill be performed by increasing the human error probability (HEP) values by a factor of10 for the new and revised HEPs without talk-through documentation with Operations.The increas ed HEP values will be quantified in the PRA model to determine the impactof the sensitivity study. Gap #3 will be addressed in accordance, with the SFCP. Gap#3 will be tracked in the PRA Configuration Control (PRACC) database and assessedfor inclusion in the nextMPS3.PRA model update..Gap # 4 (HR-G7) is based on several numerical inconsistencies in the supOporting HEPdependency analysis.DNC performed a sensitivity study associated with the, dependent HEPs calculationerrors identified by the peer review team. Three errors out of approximately 80dependent HEPs were identified.Dependent HEP Previous UpdatedHEP-DEP-63 1.1OE-02 7.OOE-03HEP-DEP-64 5.70E-04 5.80E-04,HEP-DEP-67 3.30E-04 5.OOE-04The following table provides a cross-reference between the dependent HEPs and theindividual HEPs.Dependent HEP Individual HEPs*HEP-DEP-63 HEP-C-BAF HEP-C-MFWHEP-DEP-64 HEP-C-SGI HEP-C-MFW HEP-C-BAFHEP-DEP-67 HEP-C-FTSAFW HEP-C-BAF HEP-C-MFW* Following is description of the individual HEPs:HEP-C-BAF Operators Fail to Initiate Bleed and Feed Following a Lossof Auxiliary Feedwater*(AFW)HEP-C-MFW Operators Fail'to Re-Establish Main Feedwater and Condensate to the SteamGenerators (SGs)HEP-C-SGI Operators Fail to Isolate Faulted SG During Steam ,Generator Tube Rupture(SGTR)HEP-C-FTSAFW Operators Fail to Start the Affected AFW Pump Given Auto Failure of Auto Actuate Serial No. 12-764Docket No. 50-423Attachment 1, Page 5 of 11The model, M310A, was then requantified with the updated dependent HEPs.following table provides the changes in core damage frequency (CDF) and largerelease frequency (LERF)..TheearlyModel Results CDF (/yr) LERF (/yr)Current (M31OA) 4.19E-06 6.89E-08Updated 4.13E-06 6.63E-08Delta -6.OOE-08 -2.60E-09In addition, the individual HEP importance measures were compared to evaluate anysignificant change. The following tables provide the change in the Fussell-Vesely (FV)and Risk Achievement Worth (RAW) importance measures. associated with coredamage and large early release, frequencies.HEP M310A CDF Updated CDFFV RAW FV, RAWHEP-C-BAF 1.22E-02 2.10 1.24E-02 2.11THEP-C-MFW 5.56E-03 1.12 5.64E-03 1.12HEP-C-SGI 8.90E-06 1 9.03E-06 1HEP-C-FTSAFW was truncated (i.e., not included in the modelresults)HEP M310A LERF Updated LERFFV RAW FV RAWHEP-C-BAF 2.99E-02 3.68 3.1OE-02 3.79HEP-C-MFW 5.18E-03 1.11 5.38E-03 1.11HEP-C-SGI 6.02E-04 1.16 6.25E-04 1.16HEP-C-FTSAFW was truncated (i.e., not included in themodel results)As shown above, updating the numerical inconsistencies for the three dependent HEPsresults in a negligible impact on the overall risk (CDF and LERF) and the individual HEPimportance measures. However, until these inconsistencies have been incorporatedinto the MPS3 PRA model, a sensitivity study will be performed as stated in thesubmittal of October 4, 2012. Gap #4 will be tracked in the PRACC database andassessed for inclusion in the next MPS3 PRA model update.

Serial No. 12-764Docket No. 50-423Attachment 1, Page 6 of 11Question 7Gap #11. Describe the process for identifying human-induced flooding scenarios, anddiscuss its applicability to TSTF-425 application.DNC ResponseMaintenance induced flood scenarios are covered in GARD NF-AA-PRA-101-2073,Flood-Induced Initiating Events. In addition, maintenance-induced flooding scenariosare documented in MPS3 PRA Internal Flooding notebook IF.2 Revision 4, whichstates:"Maintenance that is conducted while the plant is online in which a closed systemis opened is generally limited to cleaning and inspection of heat exchangers andair compressors. It is possible that, when performing these maintenanceactivities, that either the wrong component is isolated or maintenance opens thewrong component. Both of these situations result in a flood initiating event. It isassumed that as the component is opened, water begins to leak out of thecomponent boundary in the form of spray or jets, at which time the mistake isnoticed, and recovery actions are taken. Thus, only equipment within the areathat may be affected by spray or jet impingement damage are assumed to fail,and there is no propagation to other areas and no damage due to submersion.Each flood area was then reviewed, analyzed and documented for maintenance-induced flooding events."GAP #11 is a documentation issue only. In accordance with NEI 04-10, only open gapsthat would impact the results of the SFCP PRA assessment require sensitivity studies.Question 8Please identify the plan for closing findings that are identified as "Documentation, issuesonly."DNC Response"Documentation, issues only" findings are tracked in the PRACC database. GARD NF-AA-PRA-101-4040, PRA Model Update Planning Guidelines, provides instructions toensure the items contained in the PRACC database are assessed for closure andmodel incorporation during the nominal update cycle (approximately every 3 to 5 years).

Serial No.,12-764Docket No. 50-423Attachment 1, Page 7 of 11Question 9Table 3, "Status of Identified Gaps to Capability Category II of the ASME/ANS PRAStandard," the submittal notes that sensitivity studies will be performed in accordancewith PRA procedures for certain gap items. It is not sufficient to perform sensitivitystudies in accordance with PRA procedures. The sensitivity studies must be performedin accordance with Nuclear Energy Institute (NEI) 04-10 guidance. Please make thisclarification as appropriate for the gap items.DNC ResponseSensitivity studies will be performed in accordance with NEI 04-10, Rev. 1. The PRAprocedures were developed using the guidance in NEI 04-10, Rev. 1.Question 10The submittal indicates that fire risk and seismic risk would be qualitatively assessed.However, NEI 04-10 guidance for fire events mentions quantitative assessmentmethods (fire PRA or Fire Induced Vulnerability Evaluation (FIVE)), or qualitativescreening. For seismic events, it mentions quantitative assessment (seismic PRA),qualitative assessment (seismic margins analysis), or qualitative screening. Pleasedescribe in more detail how fire and seismic events would be assessed in terms of NEI04-10 guidance.DNC ResponseDNC is committed to evaluating changes to surveillance frequencies in accordance withthe guidance provided in NEI 04-10, Rev. 1. NEI 04-10 methodology allows aqualitative screening or bounding analysis to provide justification for acceptability ofproposed surveillance frequency changes. Since the MPS3 PRA model does notcurrently include external events, the NEI 04-10 guidance will be used to evaluate thepotential risk impact of external events associated with surveillance frequency changes.Specifically, fire and seismic information from the Millstone Individual Plant Examinationof External Events (IPEEE) report will be screened. The information will be reviewedand qualitatively assessed based on engineering judgment to determine the impact ofthe external events on surveillance frequency changes.Question 11The submittal provides no discussion on assessing high winds, floods and otherexternal events. Please describe how these events would be assessed in terms of NEI04-10 guidance.

Serial No. 12-764Docket No. 50-423Attachment 1, Page 8 of 11DNC ResponseDNC is committed to evaluating changes to surveillance frequencies in accordance withguidance provided in NEI 04-10, Rev. 1. NEI 04-10 methodology allows a qualitativescreening or bounding analysis to provide justification for acceptability of proposedsurveillance frequency changes. Since the MPS3 PRA model does not currentlyinclude external events, the NEI 04-10 guidance will be used to evaluate the potentialrisk impact of external events associated with surveillance frequency changes.Specifically, flooding and other external event information from the Millstone IPEEEreport will be screened. The information will be reviewed and qualitatively assessedbased on engineering judgment to determine the impact of the external events onsurveillance frequency changes.Question 12The submittal provides no discussion on assessment for shutdown events. Pleasedescribe how these events would be assessed in terms of NEI 04-10 guidance.DNC ResponseThe MPS3 PRA model does not include shutdown modes. Changes in the surveillancefrequencies will be qualitatively assessed using guidance from NEI 04-10, Rev. 1. Inparticular, the impact of a proposed surveillance frequency change(s) will be evaluatedfor each of the following plant key safety functions during shutdown:" Decay Heat Removal" Inventory Control" Reactivity Control" Containment Control* Electric Power AvailabilityQuestion 13Table 4.3-2 shows the Emergency Generator Load Sequencer marked in the TS underthe actuation logic test column, as well as other functional units with the correspondingnotation (1). The notation (1) is shown as deleted. Notation (1) is "Each train shall betested at least every 62 days on a STAGGARD [sic] TEST BASIS." This is also thecase for notation (7) in Table 4.3-1 for different functional units. Please discuss why therequirement to test each train is being deleted and why it is consistent with the TSTF-425 program which relocates the frequency of the surveillance to the surveillancefrequency control program (SFCP).

Serial No. 12-764Docket No. 50-423Attachment 1, Page 9 of 11DNC ResponseAs described in TSTI-425, Rev.3, Section 4.0, Technical Analysis, the phrase "on aSTAGGERED TEST BASIS"- is also relocated to licensee control under the SFCP andthe defined term, which would no longer be used in TSs, is removed from the Definitionsection. Relocating the frequency requirement to perform surveillances on aSTAGGERED TEST BASIS, along with the periodicity, allows licensees the flexibility toadjust the frequency based on operational experience and risk assessment results. NEI04-10 contains information to support the correct risk modeling of surveillancefrequencies with and without a requirement to perform the surveillance on- aSTAGGERED TEST BASIS. Therefore, MPS3 TS notes/notations that describe testingof trains, functional units, etc. on a STAGGERED TEST BASIS, can be relocated to theSFCP in accordance with TSTF-425.The definition of STAGGERED TEST BASIS is being retained in MPS3 TS DefinitionSection 1 since this terminology is mentioned in Administrative TS Section 6.8.4.h,"Control Room Envelope Habitability Program," which is not the subject of thisamendment request and is not proposed to be changed. This represents anadministrative deviation from TSTF-425 with no impact on the NRC staffs model safetyevaluation dated July 6, 2009 (74 FR 31996).Question 14Similarly, surveillance requirement 4.3.2.2 deletes requirements on what to test.Discuss why it is consistent with TSTF-425.DNC ResponseThe TS mark-up for Surveillance Requirement 4.3.2.2 has been revised to relocate thesurveillance frequency to the SFCP while still maintaining the requirements onwhat totest. A revised marked-up TS page reflecting these changes is provided in Attachment2.Question 15It is noted that TS 4.8.2. 1.f is shown in the matrix table as belonging to the SFCP, but ithas no markup. Since the surveillance has -an age-related component it would not meetthe criteria to be in the SFCP. Please clarify why the submittal proposes to include TS4.8.2.1. f in the SFCP.

Serial No. 12-764Docket No. 50-423Attachment 1, Page 10 of 11DNC ResponseDNC is not proposing to relocate the surveillance frequency in Surveillance,Requirement 4.8.2.1.f. to the SFCP. DNC did not provide a mark-up for thissurveillance since it was recognized that it contains an age-related component and doesnot meet the criteria to be in the SFCP. Reference to this surveillance requirement,which appears in Attachment 4, Page 12 of 12 of DNC's October 4, 2012 submittal,should not have been included in the matrix table.Question 16The following MPS3-specific systems identified in the cross-reference table to NUREG-1431 have no corresponding standard technical specification section:,* Shutdown Margin Monitoring MPS3* pH Tri-sodium Phosphate Storage Baskets0 Steam Jet Air Ejectors* Secondary Containment MPS3In addition, the following surveillance requirement identified in the cross-reference tableis not in the TSTF-425 scope for the section "RCS Specific Activity":* Verify XE[sic]-1*33Justify why these are included in the scope of TSTF-425, or withdraw their proposedinclusion in the SFCP.DNC ResponseFor MPS3 plant-specific surveillances that do not have a corresponding 'surveillanceincluded in' the NUREG-1431 mark-ups provided in TSTF-425, DNC evaluated thesesurveillance frequencies against the four exclusion criteria delineated in TSTF-425, Rev.,3. The four criteria which exclude' surveillance' frequencies from being relocated are:* Frequencies that reference other approved programs for the specific interval(such as the Inservice Testing Program or the Primary Containment LeakageRate Testing Program);-Frequencies that are purely event driven (e.g., "Each time the control rod iswithdrawn'to the 'full out' position"),Frequencies that are event-driven but have a time component for performing thesurveillance on a onetime basis once the event occurs (e'.g., "within '24 hour2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />safter thermal power reaching > 95% RTP"); and Serial No. 12-764Docket No. 50-423Attachment 1, Page 11 of 11Frequencies that are related to specific conditions (e.g., battery degradation, age,and capacity) or conditions for the performance of a surveillance requirement(e.g., "drywell to suppression chamberdifferential pressure decrease").For the MPS3-specific surveillances listed in Question 16 above, DNC determined thatthese surveillances involve fixed periodic frequencies and do not meet any of theexclusion criteria of TSTF-425, Rev. 3. Therefore, relocation of these frequencies isconsistent with TSTF-425, Rev. 3, and with the NRC's model safety evaluation datedJuly 6, 2009 (74 FR 31996), including the scope exclusions identified in Section 1.0,"Introduction," of the model safety evaluation.The surveillance requirement for Xe-133 was added to the MPS3 TSs under License.Amendment 246 for adoption of TSTF-490, Revision 0, "Deletion of E Bar Definition andRevision to RCS Specific Activity Tech Spec." Although not specifically included in thescope of TSTF-425, its surveillance involves a fixed periodic frequency that does notmeet any of the exclusion criteria listed above. Therefore, relocation of this frequency isconsistent with TSTF-425, Rev. 3, as described above.Question 17Do the failure probabilities'of structures, systems, and components modeled in theMPS3 PRA include a standby time-related contribution and a cyclic demand-relatedcontribution? If not, please describe how standby time-related contribution is addressedfor extended intervals.DNC ResponseThe current MPS3 PRA model does not -distinguish between time-related failurecontribution (i.e.; the standby time-related failure rate) and cyclic demand-related failurecontribution (i.e., the demand stress failure probability). Since this distinction is notmade, DNC, in accordance with NEI 04-10 Rev. 1, will assume all failures are time-related. If a further breakdown of failure probability is required to remove conservatismfrom the risk impact calculation of a proposed surveillance frequency change, DNC willabide by the cautionary sentence in NEI 04-1,0, Rev. 1, Step 8, third paragraph, whichstates, "...caution should be taken in dividing the failure probability into time-related andcyclic demand-related contributions because the test-limited risk can be underestimatedwhen only part of the failure rate is considered as being time-related while this may notbe the case."

Serial No. 12-764Docket No. 50-423ATTACHMENT 2MARKED-UP TECHNICAL SPECIFICATIONS PAGEDOMINION NUCLEAR CONNECTICUT, INC.MILLSTONE POWER STATION UNIT 3 Novem.ber 3, 2000-* INSTRUMENTATIONthe frequency specified in the Surveillance Frequency Control ProgramSURVEILLANCE REQUIREMENTSJ4.3.2.1 Each ESFAS instrumentation channel and interloc and the automatic actuation logicand relays shall be demonstrated OPERABLE by performa e of the ESFAS InstrumentationSurveillance Requirements specified in Table 4.3-2.4.3.2.2 The ENGINEERED SAFETY FEAT S RESPONSE TIME* of each ESFASfunction shall be verified to be within the limit at ca.-.t ccc pcr 1 8 mcnthsi. Each verificationshall include at least one train 9,t.h tht both trains are 4v. mvAAL,; least @nee per 36 months andone channel (to include input relays to both trains) per function su'ch that 0ll c-hannckl arc crifiedat east oncc pzr N tiff 1e -mcnths whcrc N i the total .....r A .f red..d..t eh..AA .in aspocifie ESF.A. .Aiu.... .. tin ....the "T No. of Gha...l." elu... ofab .3..{* The provisions of Specification 4.0.4 are not applicable for response time verification of steamline isolation for entry into MODE 4 and MODE 3 and turbine driven auxiliary feedwaterpump for entry into MODE 3.MILLSTONE -UNIT 33/4 3-16Amendment No. 4-5, 79, 96, 4-00, 4-8-