View source for L-16-091, Revision of Flood Hazard Reevaluation Report in Response to NRC Request for Additional Information, Per 10CFR50.54(f) Regarding the Flooding Aspects of Recommendation 2.1 of the Near-Term Task Force (NTTF) Review of Insights from the Fukush

{{Adams
| number = ML16084A871
| issue date = 03/24/2016
| title = Revision of Flood Hazard Reevaluation Report in Response to NRC Request for Additional Information, Per 10CFR50.54(f) Regarding the Flooding Aspects of Recommendation 2.1 of the Near-Term Task Force (NTTF) Review of Insights from the Fukush
| author name = Payne F
| author affiliation = FirstEnergy Nuclear Operating Co
| addressee name = 
| addressee affiliation = NRC/Document Control Desk, NRC/NRR
| docket = 05000440
| license number = NPF-058
| contact person = 
| case reference number = L-16-091
| document type = Letter type:L, Report, Miscellaneous, Response to Request for Additional Information (RAI)
| page count = 62
| project = 
| stage = Response to RAI
}}

=Text=
{{#Wiki_filter:PerryNuclearPowerPlant FENOC FlEt E sAt l,6gleat Oryatiry" P.O.Box97 10 CenterRoad Perry,Ohio44081 Frank R. Payne                                                                                             440-280-7300 GeneralPlantManager,Nuclear March24,2016 L-16-091                                                                   10cFR50.54(0 ATTN: Document           ControlDesk U.S.NuclearRegulatory          Commission 11555Rockville         Pike Rockville,      MD20852

==SUBJECT:==

PerryNuclearPowerPlant DocketNo.50-440,LicenseNo.NPF-58 Revisionof FloodHazardReevaluation             Reportin Response     to NRCRequestfor Information      Pursuant   to 10 CFR50.54(flReqardinq       the FloodinqAspectsof Recommendation          2.1of the Near-Term    TaskForce     (NTTF)  Reviewof Insiqhtsfromthe Fukushima        Dai-ichiAccident   ffAC  No. MF6099)
On March12,2012,the NuclearRegulatory                Commission   (NRC)issueda lettertitled, "Requestfor Information         Pursuantto Title 10 of the Codeof FederalRegulations 50.54(f)       Regarding  Recommendations     2.1,2.3,and9.3,of the Near-Term     TaskForce Reviewof Insights        fromthe Fukushima     Dai-ichiAccident"  [Agencywide  Documents Accessand Management              System(ADAMS)AccessionNo.ML120534340],            to all power reactorlicenseesand holdersof construction            permitsin activeor deferredstatus.
Enclosure       2 of the 10 CFR50.54(f)letteraddressesNTTFRecommendation             2.1 for ffooding.Oneof the requiredresponses              is for licenseesto submitaHazard Reevaluation       Report  (HRR)   in accordance   withthe NRC'sprioritization plan. By letter datedMay11,2012(ADAMSAccessionNo.M112097A509),                        the NRCplacedthe Perry NuclearPowerPlant(PNPP)in Category3 requiring                 a responseby March12,2015.
ThefloodHRRfor PNPPwas submittedby letterdatedMarch10,2015(ADAMS AccessionNo.ML15069A056).
By letterdatedDecember11,2015,FirstEnergy                 NuclearOperating Company(FENOC) informedthe NRCstaffof a plannedrevisionto the PNPPfloodHRRto reflectthe impactof recentplantand modelingchanges,including                majorphysicalmodifications   to the streamsandwatersheds            at the site. FENOCherebysubmitsRevision1 of the PNPPfloodHRR,whichhasbeenrevisedto reflectthesesitemodifications.

Perry Nuclear Power Plant L-16-091 Page 2 There are no regulatory commitments contained in this letter. If there are any questions or if additional information is required, please contact Mr. Thomas A. Lentz, Manager -
Fleet Licensing, at 330-315-6810.
I declare under penalty of perjury that the foregoing is true and correct. Executed on March Zf , 2016.

==Enclosure:==

Flood Hazard Reevaluation Report, Revision 1 cc:     Director, Office of Nuclear Reactor Regulation (NRR)
NRC Region Ill Administrator NRC Resident Inspector NRR Project Manager

Enclosure L-16-091 Report,Revision1 FfoodHazardReevaluation (59pagesfollow)

FLOODHAZARDREEVALUATION             REPORT rN RESPONSE  TO THEso.s4(flINFORIJlATTON       RESUESTREGARDING NEAR-TERM   TASKFORCERECOMMENDATION            2.1: FLOODING for the PERRYNUCLEARPOWERPLATTIT 10 CenterRoad North Perry,OH 44081 FlrstEnergyCorporatbn 76 Soufi Main $heet Akron, OH 44308 Revision1 March2, 2016 PdnH Nam                         Slonatue Preparsr:                     KurtRob[or            ENERCON Verifien                      Sur4 Balan           ffir                     sblaau Verifier:                     Ftuddy Dahmasfi       ENERCON itili-tt,t Approwr:                      n"t s"crimo           EI.IERCON LeadReeponsibhEngineers:
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NTTF Recommendation                2.1 (HazardReevaluations):       Flooding                            Revision1 FirstEnergyCorporation                                                                               March2,2016 Table of Contents 1.0 PURPOSE           ....                                                                                    .......4 1 . 1 . B a c k g r o u n. d                                                                               ........4 1.2. Requested             Actions...                                                                     .........4 1.3. RequestedInformation                                                                                    ......5 2.0 slTE TNFORMATTON                                                                                        .........6 2 . 1 . C u r r e nD  t e s i g nB a s i s                                                                .........8 2.1.1.       LocalIntensePrecipitation             (LlP) .                                               .......8 2.1.2.       Floodingin Streamsand Rivers                                                                 ......8 2.1.3.      Dam Breachesand Failures                                                                      .....8 2.1.4.      StormSurgeand Seiche...                                                                     .......8 2.1.5. Tsunami......                                                                                   .........8 2 . 1 . 6 . l c e - l n d u c eFdl o o d i n g                                                        .........8 2.1.7. ChannelMigration                    or Diversion                                                 .......8 2.1.8.      CombinedEffectFlood(including                \Mnd-Generated     Waves)                        .....9 2 . 1 . 9 . L o wW a t e r                                                                          ...........9 2.2.       Flood-Related        Changesto the LicenseBasis                                                    .....9 2.3.       Changesto the Watershedand LocalArea since Licenselssuance                                        ......9 2.3.1.      ProbableMaximumPrecipitation                (ReferencePNPP 2015aand PNPP2016b).........10 2.3.2.      LocalIntensePrecipitation             (LlP)(ReferencePNPP 2016aand PNPP2016b) ........10 2.3.3.      Floodingin Streamsand Rivers                                                                 ....11 2.3.3.1.        MajorStream(Reference             PNPP2015c,PNPP2015p,and PNPP2015q)........11 2.3.3.2.        MinorStream(ReferencePNPP2015aand PNPP 2015b).                                         ...12 2.3.3.3.        DiversionStream(ReferencePNPP 2015aand PNPP2015b).                                     ...13 2.4.       CurrentLicensingBasisFloodProtection                and PertinentFloodMitigationFeatures..........14 3.0 

==SUMMARY==
OF FLOODHATARDREEVALUATION                                                                       .......14 3.1. Floodingin Streamsand Rivers(ReferencePNPP 2015a,PNPP 2015b, PNPP 2015c, P N P P2 0 1 5 j P  , N P P2 0 1 5 n ,P N P P2 0 1 5 o ,P N P P2 0 1 5 p a
                                                                           , n d P N P P2 0 1 5 q ).       ........15 3 . 1 . 1 . B a s i so f I n p u t s. .: .                                                             ......16 3.1.2.      ComputerSoftwarePrograms                                                                  .......17 3 . 1. 3 . Methodology.                                                                                .....17 3 . 1. 4 . Results                                                                                   .......20 3.2.       Dam Assessment(ReferencePNPP2015d)                                                              ......21 3 . 2 . 1 . B a s i so f I n p u t s . . . .                                                            .....21 3.2.2.      ComputerSoftwarePrograms                                                                  .......21 3.2.3. Methodology                                                                                      .....22 3.2.4. Results                                                                                        .......22 PERRYNUCLEARPOWERPLANT                                                                                Page 1 of 42

NTTF Recommendation                2.1 (HazardReevaluations):       Flooding                   Revision1 FirstEnergyCorporation                                                                     March2,2016 3.3.      lce-lnduced      Flooding(Reference          PNPP2015e)                               .......22 3.3.1. Basisoflnputs....                                                                       .....22 3.3.2.         ComputerSoftwarePrograms                                                      .......22 3.3.3.         Methodology.                                                                    .....22 3.3.4.         Results                                                                       .......22 3.4.ChannelMigrationorDiversion(ReferencePNPP2015e).
3 . 4 . 1 . B a s i so f I n p u t s . . . .                                                  ......24 3.4.2.         ComputerSoftwarePrograms                                                      .......24 3.4.3.         Methodology                                                                    ......24 3.4.4.         Results                                                                       .......24 3.5. Storm Surge (ReferencePNPP 2015f, PNPP 20159, PNPP 2015h, PNPP 2015k, and P N P P2 0 1 5 r )                                                                                  ...24 3 . 5 . 1 . B a s i so f I n p u t s . . . .                                                   .....25 3.5.2.         ComputerSoftwarePrograms                                                      .......25 3.5.3.         Methodology.                                                                    .....25 3.5.4.         Results                                                                       .......27 3.6.      TsunamiAssessment(ReferencePNPP2015i)                                                .,......28 3 . 6 . 1 . B a s i so f I n p u t s . . . .                                                  ......28 3.6.2.         ComputerSoftwarePrograms                                                      .......28 3.6.3.         Methodology                                                                    ......28 3.6.4.         Results                                                                       .......29 3.7.      CombinedEffectFlood(including\Mnd-Generated                 Waves)(ReferencePNPP 2015m)..29 3 . 7 . 1 . B a s i so f I n p u t s . . . .                                                  ......30 3.7.2.         ComputerSoftwarePrograms                                                      .......30 3.7.3.         Methodology.                                                                    .....31 3 . 7 . 3 . 1 . H . 4 . 1C o m b i n a t i o. n                                        .........31 3.7.3.2.        H.4.2Combination            Alternatives.                             ..........31 3.7.4. Results                                                                               .......31 3.8.       Local IntensePrecipitation            (ReferencePNPP 2015c,PNPP 2016a,and PNPP 2016c)...31 3 . 8 . 1 . B a s i so f I n p u t s . . . .                                                  ......31 3.8.2.         ComputerSoftwarePrograms                                                      .......32 3.8.3.         Methodology                                                                    ......32 3.8.4. Results                                                                               .......33 4.0 COMPARISONOF BEYONDDESIGNBASISWITH UPDATEDDESIGNBASIS                                             ....33 5 . 0 I N T E R I MA N D P L A N N E DF U T U R EA C T I O N S                                    ........37 6.0 ACRONYMS                                                                                        ......38 7.OREFERENCES                                                                                    .........39 PERRYNUCLEARPOWERPLANT                                                                      Page 2 of 42

NTTF Recommendation  2.1 (HazardReevaluations).
Flooding                    Revision1 FirstEnergyCorporation                                               March2.2016 ATTACHMENT   1 - UpdatedDesignBasisLIP FloodHazardResultsDoorSchedule..........8 Pages ATTACHMENT2 - BeyondDesignBasisLIP FloodHazardResultsDoorSchedule.... 8 Pages PERRYNUCLEARPOWERPLANT                                                Page 3 of 42

NTTF Recommendation     2.1 (HazardReevaluations):     Flooding                        Revision1 FirstEnergyCorporation                                                             March2.2016 1.0 PURPOSE 1.1.Background In responseto the nuclearfuel damageat the FukushimaDai-ichipowerplantdue to the March 11, 2011 earthquake and subsequent tsunami, the United States Nuclear Regulatory Commission(NRC) establishedthe Near Term Task Force (NTTF) to conducta systematic review of NRC processesand regulations,and to make recommendations          to the NRC for its policydirection.The NTTF reporteda set of recommendationsthat were intendedto clarifyand strengthenthe regulatoryframeworkfor protectionagainstnaturalphenomena.
On March 12,2012 the NRC issuedan informationrequestpursuantto Title 10 of the Code of FederalRegulations,Section50.54(f) (10 CFR 50.54(f)or 50.54(f)letter)whichincludedsix (6) enclosures:
: 1. NTTF Recommendation       2.1: Seismic
: 2. NTTF Recommendation       2.1: Flooding
: 3. NTTF Recommendation       2.3: Seismic
: 4. NTTF Recommendation       2.3: Flooding
: 5. NTTF Recommendation       9.3: EP
: 6. Licenseesand Holdersof ConstructionPermits In Enclosure2 of the NRC-issuedinformationrequest(ReferenceNRC March 2012),the NRC requested that licensees reevaluatethe flooding hazards at their sites against present-day regulatoryguidanceand methodologiesbeing used for early site permits(ESP) and combined operatinglicensereviews.
On behalf of FirstEnergyNuclearOperatingCompany(FENOC)for the Perry NuclearPower Station (PNPP), this Flood Hazard ReevaluationReport (Report) providesthe information requested in the March 12, 2012 50.54(f) letter; specifically,the informationlisted under the "RequestedInformation"sectionof Enclosure2, paragraph1 ('a' through'e'). The "Requested fnformation"sectionof Enclosure2,paragraph2 ('a'through'd'), IntegratedAssessmentReport, or other additionalfuture assessmentsas necess?r'y,will be addressedseparatelyif the current designbasisfloodsdo not boundthe reevaluatedhazardfor all flood-causingmechanisms.
1.2. RequestedActions Per Enclosure2 of the NRC-issuedinformationrequest,50.54(f)letter,FENOCis requestedto performa reevaluation of all appropriateexternalfloodingsourcesfor PNPP,includingthe effects from localintense  precipitation (LlP)on the site,the probablemaximumflood (PMF)on streams and rivers, lake floodingfrom storm surges, seiches, and tsunamis,and dam failures.lt is requestedthat the reevaluation  applypresent-dayregulatoryguidanceand methodologies     being used for ESPs, combinedoperatinglicensereviews,and calculationreviewsincludingcurrent techniques,software,and methodsusedin present-day        standardengineeringpracticeto develop the flood hazard The requestedinformationwill be gatheredin Phase 1 of the NRC staffs two-phase process to implement Recommendation2.1, and will be used to identify potential "vulnerabilities" (see definitionbelow).
PERRYNUCLEARPOWERPLANT                                                               Page 4 of 42

NTTF Recommendation      2.1 (HazardReevaluations):     Flooding                              Revision1 FirstEnergyCorporation                                                                    March2.2016 The NRC prioritizationof responsesletter (ReferenceNRC May 2012) identifiesPNPP as a Category3 site. Licenseesin this categoryare expectedto reportthe resultsof the reevaluation withinthreeyearsof the March 12, 2012 50.54(f)letterissuance.
For the sites where the reevaluatedflood exceedsthe design basis,addresseesare requested to submit an interimaction plan documentingplannedactions or measuresimplementedto addressthe reevaluatedhazards.
Subsequently,addresseesshall performan integratedassessment,or other additionalfuture assessmentsas necessary,of the plant to fully identifyvulnerabilitiesand detail actions to addressthem.The scope of the integratedassessmentreportwill rncludefull poweroperations and otherplantconfigurations      that could be susceptibledue to the statusof the flood protection features.The scope also includesthose featuresof the ultimateheat sink (UHS)that could be adverselyaffectedby flood conditions(the loss of UHS from non-floodassociatedcauses is not included).lt is also requestedthat the integratedassessmentaddressthe entiredurationof the flood conditions.
A definition of vulnerabilityin the context of Enclosure 2 is as follows: Plant-specificvulnerabilities are those features important to safety that when subject to an increaseddemand due to the newly calculated hazard evaluation have not been shown to be capable of performing their intended functions.
1.3. RequestedInformation Per Enclosure2 of the NRC-issuedinformationrequest50.54(f)letter,the Reportshouldprovide documentedresults,as well as pertinentPNPP informationand detailedanalysis,and include the following:
: 1. Site informationrelatedto the flood hazard. Relevantstructure,systems,and components (SSCs)importantto safetyand the UHS are includedin the scopeof this reevaluation,             and pertinentdata concerningthese SSCs should be included.Other relevantsite data include the following:
: 1. Detailedsite information      (bothdesignedand as-built),includingpresent-day          site layout,elevationof pertinentSSCsimportant        to safety,sitetopography,  andpertinent spatialandtemporaldatasets;
: 2. Currentdesignbasisfloodelevations        for allflood-causing   mechanisms;
: 3. Flood-relatedchanges to the licensing basis and any flood protection changes (includingmitigation)   sincelicenseissuance; 4 . Changesto the watershedand localarea sincelicenseissuance; 5 . Currentlicensingbasis flood protectionand pertinentflood mitigationfeaturesat the site;and
: 6. Additionalsite details,as necessary,to assessthe floodhazard(e.g.,bathymetryand walkdownresults).
: 2. Evaluationof the flood hazard for each flood-causingmechanism,based on present-day methodologiesand regulatory guidance. Provide an analysis of each flood-causing mechanismthat may impactthe site,includingLIP and site drainage,floodingin streamsand rivers,dam breachesand failures,storm surge and seiche,tsunamis,channelmigrationor diversion,and combinedeffects.Mechanismsthat are not applicableat the site may be PERRYNUCLEARPOWERPI.ANT                                                                     Page 5 of 42

NTTF Recommendation      2.1 (HazardReevaluations): Flooding                          Revision1 FirstEnergyCorporation                                                            March2,2016 screened out; however, a justificationshould be provided. A basis for inputs and assumptions,   methodologies  and modelsused, includinginput and output files, and other pertinentdata shouldbe provided.
3 . Comparisonof currentand reevaluatedflood-causingmechanismsat the site. Providean assessmentof the currentdesignbasisfloodelevationto the reevaluatedfloodelevationfor each flood-causingmechanism.Includehow the findingsfrom Enclosure2 of the 50.54(D letter(i.e., Recommendation  2.1, flood hazardreevaluations)  supportthis determination.lf the current design basis flood bounds the reevaluatedhazard for all flood-causing mechanisms,    includehow this findingwas determined.
4 . Interimevaluationand actions taken or plannedto address any higher flooding hazards relativeto the designbasis,priorto the completionof the integratedassessmentor any future assessments.
: 5. Additionalactions beyond requestedinformationitem 1.d taken or planned to address floodinghazards,if any.
2.0 SITE INFORMATION PNPP is locatedin LakeCounty,Ohio,approximately       sevenmiles northeastof Painesville.The southernplantsite boundaryline is 3,100feet from the shorelineof Lake Erie on the west side of the site and 8,000 feet on the east side (USAR,Section2.4.1.1).Lake Erie is the major hydrologicfeatureof the location.In the vicinityof the site,the coastalwatershedis drainedby severalsmall streams(USAR,Section2.4.1.2).Three namelessstreamsrun closeto the plant area. The Major Stream has a drainagebasin of 7.44 square miles (ReferencePNPP 2015p) and runs northwestwardwithin 1,000feet of the southwestcornerof the plant.The MinorStream has a drainagearea of only 0.11 squaremiles(ReferencePNPP 2015b)and bordersthe plant area to the east. The DiversionStream has a drainagearea of 0.59 square miles (Reference PNPP2015b)and is locatedeast of the MinorStream.The DiversionStreamdivertsrunoffflow upstreamof the Minor Stream east aroundthe outsideof the securitybarriersand north directly to Lake Erie. The safety-relatedstructuresof the plant are locatedwithin an isolateddrainage area and withinthe drainagebasinof the MinorStream.Finalgradeelevationsin the immediate plantarea vary from 617 to 620 feet (USGS)(USAR,Section2.4.2.2).The floorsat plantgrade are set at Elevation620.5 feet (USGS)(USAR,Section2.4.2.3).Note that the UpdatedSafety Analysis Report (USAR) presentselevationsusing a USGS datum that is equivalentto the NationalGeodeticVerticalDatum of 1929 (NGVD29). For reference,conversionfor the North AmericanVerticalDatum of 1988 (NAVD 88) and for the InternationalGreat Lakes Datum of 1985(IGLD85) are providedin Table1 (ReferencePNPP2015band PNPP2015h).The present-day site layoutis shownin Figure2.0.1.
Table I - Datum Conversions (feet)
NGVD29       NAVD 88       IGLD 85 0.00         -0.72         -0.94 PERRYNUCLEARPOWERPLANT                                                              Page 6 of 42

NTTFRecommendati  on 2.1 (HazardReevaluations)
: Flooding               Revision1 FirstEnergyCorporation                                           M a r c h2 , 2 0 1 6 Figure2.O.1- Present-Day  Site Layout PERRYNUCLEAR    POWERPLANT                                        Page 7 of 42

NTTFRecommendation       2.1 (HazardReevaluations):  Flooding                          Revision1 FirstEnergyCorporation                                                             March2,2016 2.1.GurrentDesignBasis The currentdesignbasisas referencedby the PNPPUpdatedSafetyAnalysisReport(USAR)is providedin Section2.1.The followingis a listof flood-causingmechanismsand theirassociated water surfaceelevationsthat were consideredfor the PNPP currentdesign basis.Section2.3 includesdiscussionof the updateddesignbasisanalyses.
2.1.1. Local IntensePrecipitation(LlP)
The USAR indicatesthat the precipitation  value ol26.7 inchesover a 6-hourperiod,with the maximumhourlyrainfallof 13.1inchesoccurringduringthe first hour,is utilizedfor the LIP analysis.In the case of completeblockageof the storm drainagesystem,the plantsite has been gradedso that overlanddrainagewill occur away from the plantsite buildingsand will not allow the accumulatedstorm water to exceed Elevation620.5 feet (USGS) (USAR, Section2.4.2.3).
2.1.2. Flooding in Streams and Rivers The USAR identifiesa flow rate of 31,250cubic feet per second (cfs) for the Major Stream and 7,000cfs for the MinorStream(USAR,Section2.4.3).The MajorStreamwater surface elevationupstreamof the plantaccessroadforthe PMF was foundto be 624.0feet (USGS) until this surface met the normal depth of flow in the existing stream. This water surface elevationwill safely pass beneaththe railroadbridge (USAR, Section2.4.3.5).The Minor Streamwater surfaceelevationwas foundto be 619.5feet (USGS)(USAR,Figure2.4-B).
2.1.3. Dam Breachesand Failures The USAR identifiesno impoundmentsupstreamof the plant.Therefore,dam failureis not includedas a designcondition(USAR,Section2.4.4).
2.1.4. Storm Surge and Seiche The probablemaximummeteorological      event in Lake Erie resultsin a maximumstillwater surfaceelevationof 580.5 feet (USGS)(USAR,Section2.4.5.2.2).The probablemaximum storm (PMS)was assumedto occur over a72-hour period,duringwhich the winds increased from 20 milesper hourto the maximumspeedof approximately103 milesper hour overthe lake and then decreasedto less than 35 miles per hour in the Perry area (USAR,Section 2.4.s.1.3).
2.1.5. Tsunami Sincethe site is locatedon Lake Erie,an inlandlake,tsunamioccurrenceis not applicable (USAR,Section2.4.6).
2.1.6. lce-lnducedFlooding lce floodingcannotoccurbecauseof the highbluffsbetweenthe buildingsand the lake.Also, safety-relatedonshorebuildingsare set backfrom the top of the 45-foothigh bluffto preclude ice forcesbeinga problem(USAR,Section2.4.7.4).
2.1.7. GhannelMigrationor Diversion Channeldiversionis not applicableto PNPPsinceno coolingwaterchannelsexistfromwhich flow could be diverted(USAR,Section2.4.9).
PERRYNUCLEAR         POWERPLANT                                                      Page 8 of 42

NTTF Recommendation     2.1 (HazardReevaluations): Flooding                           Revision1 FirstEnergyCorporation                                                            March2,2016 2.1.8. CombinedEffect Flood (includingWind-GeneratedWaves)
       \Mnd wave activity,includingrunup,was evaluatedas part of the surge analysis.Runup occurringcoincidentally with the probablemaximumsetupwould extendto about elevation 607.9feet (USGS)on the bluffat the lakeshore(USAR,Section2.4.2.2).
2.1.9. Low Water No water is takenfrom the MajorStreamor Minor Stream.Therefore,low flows in the streams will not affectPNPPoperation.
The UHS for PNPPis LakeErie.Submergedoffshoreintakessupplywaterto the emergency service water pumphouse.All safety-relatedpumps and equipmentare located above elevation586.5 feet (USGS)in the emergencyservicewater pumphouse(USAR, Section 2.4.10).The emergencyservicewater pumphouseand emergencyservicewater pumpsare designedto provideservicecapacityunder all lake level conditionsdown to 565.26 feet (USGS) level caused by the probablemaximumsetdownsuperimposedon the minimum monthlymean lake level(USAR,Section2.4.11.6).Two verticalshaftsconveywater intothe intake tunnel. The intake heads are covered with a velocity cap to prevenUminimize whirlpooling.\Mth the invertsof the intake ports at an average elevationof 552.65 feet (USGS), inflow of sufficient cooling water is assured (USAR, Section 2.4.11.5).The correspondingwater level in the emergencyservice water pump chamber would be at elevation562.09feet (USGS).
2.2. Flood-RelatedChanges to the License Basis Therewere no changesto the flood-relatedlicensebasissincethe initiallicenseissuance.
2.3. Ghangesto the Watershedand Local Area since License lssuance An engineeringchange package (ReferencePNPP ECP 13-0802) implementedin 2015 establishedthe updateddesign basis for the LIP and the floodingin streams and rivers as discussed in the following subsections.The analyses supportingthe engineeringchange packageare based on the 2012 aerialsurvey conductedby Sanborn.The Sanbornsurvey is referencedto the NAVD 88 datum.Therefore,the analyseswere conductedusingthe NAVD 88 datum with final results convertedto a datum consistentwith the plant. The basis of the conversionoriginallyused a generalconversionfrom NAVD 88 to NGVD 29. ConditionReport CR 2015-05079(ReferencePNPPCR 2015-05079)addressedthatthe conversionfactoris more accuratewhen basedon the localonsiteplantmonuments.The conversionwas adjustedby 0.21 feet and a new conversionfactor is used (NAVD 88 + 0.93 ft = Perry Local Datum and IGLD 85
   + 1.15ft = Perry LocalDatum).The resultspresentedhereinare in the Perry LocalDatum.The PerryLocaldatumwas originallybasedon and withinthe tolerancelevelsof the NGVD29 datum.
The engineeringchange package included site modificationsto the Major Stream and establishedthe DiversionStreamto reroutethe south reachesof the Minor Stream as shown in Figure2.0.1.The engineeringchangepackageincorporatedremovalof a portionof the existing abandonedrail line embankmentto the southwestof the rail line bridge crossingthe Major Stream.Removalof the embankmentallowsgreaterconveyanceof flow in the overbanksof the Major Stream,preventingflow from overtoppingthe rail line. Furthermore,the secondaryaccess roadwas raisedto preventany remainingbackwaterfrom overtoppingthe road.This modification identifiedin Figure 2.0.1 resultedin the concentrationof Major Stream runoff to be carried downstreamto Lake Erie,ratherthan contributingto runoffto otherareasof the site.
The engineeringchangepackageincorporatedan upstreamdiversionof the MinorStream.The DiversionStream diverts runoff flow east around the outside of the securitybarriersand north PERRYNUCLEARPOWERPLANT                                                              Page 9 of 42

NTTFRecommendation       2.1 (HazardReevaluations):   Flooding                          Revision1 FirstEnergyCorporation                                                               March2,2016 directlyto Lake Erie. A berm was constructedadjacentto the DiversionStream betweenthe stream and the site. Under PMF conditionsthe berm will maintainall flood water within the DiversionStreamwatershedaway from the site. These modificationssignificantlyreducethe runoffflow receivedby the MinorStream.
Basedon aerialimagesof the watershed,other changesto the watershedincludecommercial developmentwithin the watershedarea, which is a small percentageof the overallwatershed area. The changesto the local area sub-watershed     for PNPP includebuildingsthat have been addedor removedand securitybarrierupgradesthat have been addedto the site since license issuance.
2.3.1. ProbableMaximum Precipitation(ReferencePNPP 2015aand PNPP2016b)
The designbasisrainfallis determined  usingthe U.S.Bureauof Reclamation      Designof Small Dams,SecondEditionguidance(ReferenceUSBR 1973)as referencedby the USAR.The guidanceincorporatesHydrometeorological       Report No. 33 (ReferenceNOAA 1956) and includesa recommendedarea reductionfactorfor smalldrainageareas.The CorrectedPMP utilizingthe area reductionfactor is a front loadedtemporaldistributionevent having 10.5 inchesof rainfalloccurringthe first hour and 21.4 inchesover the entire6-hourperiod.The UncorrectedPMP does not incorporatethe area reductionfactorand is characterizedby 13.1 inchesin the first hour and a 6-houraccumulation    ol 26.7 inches(USAR,Section2.4.3.1).
Table2 providesa descriptionof the PMP events.
Table2-PMPGomparison Duration(hours)                 1      2      3      4      5     6 Uncorrected PMP (inches) 1 3 . 1 1 7 . 1 20.0 22.4 24.6 26.7 CorrectedPMP(inches)          1 0 . 5 13.7 1 6 . 0 1 7 . 9 19.7 2 1 . 4 2.3.2. Local Intense Precipitation(LlP) (ReferencePNPP 2016aand PNPP2016b)
The effectsof LIP were analyzedusing FLO-2Dhydraulicssoftwareto establishthe updated designbasis,includingthe impactsof site streammodifications.      The softwareuses shallow water equationsto route stormwaterthroughoutthe site. The Major Stream is incorporated into the model as a staticwater level boundarycondition.The Minor Streamwatershedis incorporatedinto the modeling.The DiversionStream and associatedwatersheddo not affectthe area of the power block analyzedfor the effectsof LlP. The DiversionStreamand associatedwatershedalso do not affectthe MajorStreamor the MinorStream.The Diversion Streamis not includedin the FLO-2Dmodeling.
Buildingsand securitywall barriersare incorporated   intothe modelas obstructions. The site storm drainage network is incorporated into the model using the S\AAIM software incorporatedinto the FLO-2Dsoftware.The elementsof the roof drain systemthat connect directlyto the storm drainagenetworkor groundwaterare incorporatedinto the model.Roof drains that dischargedirectlyto the ground are not modeled.The site also includesan underdrainsystemthat is independentof the storm drainagenetwork.Sixteenunderdrain manholelocationsare modeledas open inlets.A forthcomingmodificationis in development for the underdrainsystem to allow for manhole structuresto intake surface water. The modificationis requiredto validatethe LIP analysisdiscussedin this section.The plant is currentlyoperatingunder PFA 2015-08036(ReferencePNPP CR 2015-08036)due to the potentialfloodingat the site.
PERRYNUCLEARPOWERPLANT                                                                Page 10 of 42

NTTF Recommendatlon      2.1 (HazardReevaluations): Flooding                         Revision1 FirstEnergyCorporation                                                            March2,2016 FLO-2D softwarepresentsan efficientphysicalprocess model that assess the established conceptsof unsteadyflow analysis.FLO-2Dis a volume conservationflood routingmodel incorporatinga grid system to evaluate topography. FLO-2D solves finite difference approximations  of the continuityand momentumequationsto computeflow in eightdirections for each grid cell.The continuityand momentumequationsare the underlyingequationsfor unsteadyflow analysis.Unsteadyflow is referencedfor streamcoursemodelingby the design basis guidancestandardof the American NationalStandardsInstitute(ANSI) (Reference ANS! N170-1976).
To determinethe associatedfloodingelevations,the CorrectedPMP identifiedin Table 2 is appliedevenlyacrossthe site. No rainfalllossesare includedin the modeling.The effectsof LIP producemaximumwater surfaceelevationsat the power block rangingfrom 619.8 feet Perry Local Datum to 620.7feet Perry Local Datum. In general,the south end of the power blockaroundthe Unit2 TurbineBuildingresultsin highermaximumwatersurfaceelevations.
The resultingmaximumwater surfaceelevationsexceed26 door thresholdelevationsof the powerblock.The maximumwater depthsat the 26 door locationsrangefrom 0.1 feet to 0.4 feet abovethe door thresholdelevationsfor durationsrangingfrom 0.3 hoursto 6 hours.
Maximumwatersurfaceelevationsnorthof the powerblockat the ServiceWaterPumphouse Buildingand the EmergencyServiceWater PumphouseBuildingrangefrom 619.1feet plant datum to 620.0 feet plant datum. The resultingmaximumwater surfaceelevationsdo not exceeddoor thresholdelevationsat the ServiceWater Pumphouse.The resultingmaximum water surface elevations exceed two door thresholds and one louver opening of the EmergencyService Water Pumphouse.The maximum water depths at the three door locationsrangefrom0.3 feetto 0.5 feet abovethe openingelevationsfor durationsof 6 hours.
The doors olthe CirculatingWater pumphousesat each coolingtower are not affectedby the effectsof LIP flooding.
2.3.3. Flooding in Streams and Rivers As a resultof the site modificationsin 2015,the floodingin streamsand riverswere analyzed to establishthe updateddesignbasis.
2.3.3.1. Major Stream (ReferencePNPP2015c,PNPP2015p,and PNPP2015q)
The Major Stream PMF is the flood resultingfrom the 72-hourdurationsite-specific,all-seasonprobablemaximumprecipitation(PMP).Front,one-third,center,two-thirds,and end-loadingtemporaldistributionsare consideredin an effortto capturethe distribution that maximizesrunoff.Cool-seasonalternativesare boundedby the all-seasonresults.
The U.S. Army Corps of Engineers(USACE)HEC-HMShydrologicsoftwareis used to convertrainfallto runoff.A rainfallhyetographis appliedto the MajorStreamwatershed and the NationalResourcesConservationService(NRCS)unit hydrographmethodology is used for rainfall-to-runoff transformation. The unit hydrographis modifiedto account for the effectsof nonlinearbasinresponseby increasingthe peak of the unit hydrograph by one-fifth and reducing the time-to-peakby one-third.An estimated base flow is includedin the analysisand no precipitationlossesare incorporated.
The unsteadyflow simulationmodulewithinthe USACE HEC-RASsoftwareis used to transformthe resultingflow hydrographinto a water surfaceelevationhydrograph.The cross sectionsreflectthe removalof a portionof the rail line embankment.The plant access road and culvert is includedin the model. The upstream rail line bridge is incorporated  intothe model.The upstreamsecondaryaccessroadis includedas an inline PERRYNUCLEARPOWERPLANT                                                            Page11 of 42

NTTF Recommendation     2.1 (HazardReevaluations):   Flooding                        Revision1 FirstEnergyCorporation                                                            March2,2016 structureand all flow overtopsthe road.A boundingwater level in Lake Erie is used as the downstreamboundarycondition.
The area betweenthe rail line spur and the secondaryaccessroad in the overbankon the northeastside of Major Stream would be subjectto the effects of localizedPMP rainfall.The area is evaluatedusing a HEC-HMSlevel-poolstorageroutingmodel.The same site-specificPMP is appliedto the model. No losses are incorporatedinto the analysis.Dischargefrom the area is determinedbasedon weir flow over the rail line.
The analysisdoes not resultin overtoppingof the rail line bridgestructure.Furthermore, MajorStreamfloodingupstreamof the raillineis preventedfromencroachingon adjacent areasby the elevatedembankmentof the rail line spur in the overbankon the northeast side of the MajorStream.The resultingmaximumwater levelsfor the MajorStreamare not adjacentto the powerblock.The raisedsecondaryaccessroad is also not overtopped by the localizedfloodingof the area betweenthe rail line spur and the secondaryaccess road. Therefore,the Major Stream does not contributeto floodingeffectsin the Minor Stream,the DiversionStream,or the power blockarea.The one-third,center,and two-thirds temporal distributionsproduce identicalpeak results and the maximum water levels.The maximumwater surfaceelevationat the rail line bridgestructureis 628.5feet Perry Local Datum,with a maximumflow of 34,200cfs at the bridge.The maximumwater surface elevationproducedfor the area between the rail line spur and the secondary accessroad is 631.4feet PerryLocalDatum.
A boundingapproachis taken in the analysisof the floodingeffectsof MajorStream.The boundingapproachdetermineda more conservativecase betweendesign basis and beyonddesignbasisintoone analysisfor the developmentand implementation      of stream modifications. The boundingPMP appliedis the beyonddesignbasissite-specificPMP as definedin Table3.
Table 3 - Site-SpecificPMP Duration(hours)      1       2      3     4      5       6    12   24   48     72 PMP (inches)       1 2 . 1 1 3 . 6 14.8 1 5 . 9 1 7 . 0 18.1 24.0 25.5 26.1 26.6 In initialappearancesthe UncorrectedHMR 33 PMP appearsto boundthe site-specific PMP as it has the largerhourlyand cumulativestormdurationPMP totals.However,the site-specific PMP is evaluated using S-minute increments based on the Hydrometeorological  ReportNo. 52 (ReferenceNOAA 1982)sub-hourlyratios,whichare not distributedlinearlyas in the designbasis methodologyutilizingHydrometeorological ReportNo. 33. Due to the smalldrainageareasand short responsetime,the sub-hourly PMP incrementsare criticalin determiningthe PMF, by producingmore conservative inflowhydrographsand ultimatelyproduceshigherflow rates.
As shown in Table2, the UncorrectedPMP is greaterthan the CorrectedPMP. Therefore, PMP is a boundingapproachfor the MajorStreamupdateddesign use of the site-specific basisinputrainfall.
2.3.3.2. Minor Stream (ReferencePNPP 2015aand PNPP 2015b)
As a boundingapproach,the Minor StreamPMF is the flood resultingfrom the 48-hour duration UncorrectedHydrometeorological       Report No. 33 PMP. Ratios provided by HydrometeorologicalReport No. 52 are used to define sub-hourly increments.
IntermediateS-minuteincrementalPMP depthsare determinedfor point precipitation(1 PERRYNUCLEARPOWERPLANT                                                            Page 12 of 42

NTTF Recommendation    2.1 (HazardReevaluations):  Flooding                         Revision1 FirstEnergyCorporation                                                          March2,2016 squaremile).Front,one-third,center,two-thirds,and end-loadingtemporaldistributions are consideredin an effortto capturethe distributionthat maximizesrunoff.Cool-season alternativesare boundedby the all-seasonresults.
The USACEHEC-HMShydrologicsoftwareis usedto convertrainfallto runoff.The Minor Stream watershed is subdividedinto three (3) sub-watersheds(a small remainingarea southof the site,the MinorStreamand site area contributingto the MinorStreamat the lateral swale between the two cooling towers, and the small remaining area of the unnamedtributaryeast of the securitybarriers)basedon the topographyof the site and reflectingthe constructionof the DiversionStream.A rainfallhyetographis appliedto the sub-watershedsand NRCS unit hydrographmethodologyis used for rainfall-to-runoff transformation. The unit hydrographsare modifiedto accountfor the effectsof nonlinear basin responseby increasingthe peak of the unit hydrographby one-fifthand reducing the time-to-peakby one-third.An estimatedbase flow is includedin the analysisand no precipitationlossesare incorporated.
The unsteadyflow simulationmodulewithinthe USACE HEC-RASsoftwareis used to transformthe resultingflow hydrographinto a water surfaceelevationhydrograph.One crossingis incorporatedintothe MinorStreammodel.The downstreamLockwoodRoad crossingis modeledas an inlinestructureand all flow overtopsthe road.A bounding water level in Lake Erie is used as a downstreamboundarvconditionfor the HEC-RAS softwareprogram.
The one-third,center,and two-thirdstemporaldistributions  produceidenticalpeakresults and the maximumwaterlevels.The maximumwatersurfaceelevationoccursat the cross sectioncorrespondingto the south end of the Unit 2 TurbineBuildingand is 619.7 feet PerryLocal Datum.The maximumwatersurfaceelevationprofiledecreaseto 618.7feet Perry Local Datum at the cross section correspondingto the north end of the Unit 1 Turbine Building.The maximum flow overtoppingLockwood Road downstreamis approximately1,100 cfs. Peak floodingdoes not overflowthe Minor Stream channel banksand does not reachthe powerblock.
2.3.3.3. Diversion Stream (ReferencePNPP 2015aand PNPP 2015b)
As a boundingapproach,the DiversionStreamPMF is the flood resultingfrom the 48-hour durationUncorrectedHydrometeorological    ReportNo. 33 PMP. Ratiosprovidedby HydrometeorologicalReport No. 52 are used to define sub-hourly increments.
IntermediateS-minuteincrementalPMP depthsare determinedfor pointprecipitation       (1 squaremile).Front,onethird, center,two-thirds,and end-loadingtemporaldistributions are consideredin an effortto capturethe distributionthat maximizesrunoff.Cool-season alternativesare boundedby the all-seasonresults.
The USACEHEC-HMShydrologicsoftwareis usedto convertrainfallto runoff.A rainfall hyetographis appliedto the DiversionStreamwatershedand the NRCS unit hydrograph methodologyis usedfor rainfall-to-runofftransformation. The unit hydrographis modified to accountfor the effects of nonlinearbasin responseby increasingthe peak of the unit hydrographby one-fifthand reducingthe timeto-peak by onethird. An estimatedbase flow is includedin the analysisand no precipitation lossesare incorporated.
The unsteadyflow simulationmodulewithinthe USACE HEC-RASsoftwareis used to transformthe resultingflow hydrographinto a water surfaceelevationhydrograph.The culvertat the outfallof the DiversionStream is assumedto be completelyblockedand modeled as an inline structure.A boundingwater level in Lake Erie is used as a downstreamboundaryconditionfor the HEC-RASsoftwareprogram.
PERRYNUCLEARPOWERPLANT                                                           Page 13 of 42

NTTF Recommendation     2.1 (HazardReevaluations)'  Flooding                          Revision1 FirstEnergyCorporation                                                            March2,2016 The one-third,center,and two-thirdstemporaldistributionsproduceidenticalpeakresults and the maximumwaterlevelsfor the DiversionStream.The PMF inflowhydrographhas a peak of 4,200 cfs. The maximumwater surfaceelevationoccurs at the upstreamfill area and is 629.2feet Perry Local Datum.The fill area and berm are designedwith a crest elevationof 630.9 feet Perry Local Datum. The berm constructedadjacentto the streampreventsfloodingof the site.
The DiversionStreambermwas assessedfor pipingfailureand the potentialfor impact on the Minor Streamresults.The HEC-RASmodelsused to evaluatethe effectsof the PMF are used to assessthe failure effects.The HEC-RASmodels are evaluatedusing unsteady-state flow simulation.
The peak of the failureflow hydrographaddedto the MinorStreammodelingis 670 cfs.
Becauseof the differencein responsetimes for the Minor Stream and the Diversion Stream,the additionof the failureflow hydrographextendsthe durationof floodingin the MinorStream,but the peakwatersurfaceelevationsare identicalto the PMF floodingfor the MinorStream.
2.4. Current Licensing Basis Flood Protection and Pertinent Flood Mitigation Features As a result of the updateddesign basis (ReferencePNPP 2016b),the LIP maximumwater sufface elevationsexceedthe door thresholdelevationsat severallocationsof the power block.
A summaryof the updateddesignbasisresultsare providedin Section2.3.2.The doorschedule for the updateddesignbasis LIP flood hazardresultsis providedin Attachment1. The plant is currently operating under Prompt FunctionalityAssessment (PFA) 2015-08036(Reference PNPP CR 2015-08036)due to the potentialfloodingat the site.
3.0 

==SUMMARY==
OF FLOODHAZARDREEVALUATION NUREGICR-7046,Desrgn-BasrsFlood Estimationfor Site Characterizationat Nuclear Power Plants in the United Sfafes of America (Reference NUREG/CR-7046),by reference to the AmericanNuclearSociety(ANS),states that a single flood-causingevent is inadequateas a design basis for power reactorsand recommendsthat combinationsshould be evaluatedto determinethe highestfloodwaterelevationat the site. For PNPP,the combinationthat produces the highest flood water elevationat the site safety-relatedstructuresis the effects of LlP, as providedbelow.
With the exceptionof the Lake Erie analyses,the beyonddesign basisanalysesare based on the 2012 aerialsurvey conductedby Sanborn.The Sanbornsurvey is referencedto the NAVD 88 datum. Therefore,the analyseswere conductedusing the NAVD 88 datum with final results convertedto a datum consistentwith the plant.The basis of the conversionoriginallyused a generalconversionfrom NAVD 88 to NGVD 29. ConditionReportCR 2015-05079addresses that the conversionfactor is more accuratewhen based on the local onsite plant monuments.
The conversionwas adjustedby 0.21feet and a new conversionfactor is used (NAVD88 + 0.93 feet = Perry Local Datum).
The Lake Erie analyseswere conductedusingthe IGLD85 datumwith final resultsconvertedto a datumconsistentwith the plant.The conversionalso incorporated   the generalconversionfrom NAVD 88 to NGVD 29. Therefore,a conversionadjustmentof 0.21feet is also applicable(IGLD 85 + 1.15feet = PerryLocalDatum).The resultspresentedhereinare in the PerryLocalDatum.
The Perry Local datum is originallybased on and within the tolerancelevelsof the NGVD 29 datum.
PERRYNUCLEARPOWERPLANT                                                             Page 14 of 42

NTTF Recommendation      2.1 (HazardReevaluations). Flooding                         Revision1 FirstEnergyCorporation                                                             March2,2016 The beyonddesign basis Calculation50:66.000 PNPP SiteModificationsBeyond DesignBasrs Local lntense Precipitation(Reference PNPP 2016c) defines the maximum water surface elevationsresultingfrom the LIP event at the power block. The maximum water surface elevationsat the powerblockdue to the LIP event rangefrom 619.9feet Perry Local Datumto 621.3 feet Perry Local Datum. The LIP maximumwater surfaceelevationsexceed the door thresholdelevationsat severallocationsof the powerblock.The elevationsof the site doorsare referencedto the Perry Local Datum.
The methodologyused in the floodingreevaluationfor PNPP is consistentwith the following standardsand guidancedocuments:
     . NRC StandardReviewPlan,NUREG-0800,revisedMarch 2OO7             (ReferenceNUREG-O8OO)
NUREG/CR-7046,       "Design-BasisFlood Estimationfor Site Characterizationat Nuclear Power Plants in the United States of America," dated November 2011 (Reference NUREG/CR-7046)
NUREG/CR.6966,      "TsunamiHazardAssessmentat NuclearPowerPlantSitesin the United Statesof America", dated March2009 (ReferenceNUREG/CR-6966)
        "AmericanNationalStandardfor DeterminingDesign Basis Floodingat Power Reactor Sites'],dated July 28, 1992(Reference ANSI/ANS-2.8-1992)
NEI Report12-08,"Overviewof ExternalFloodingReevaluations"        (ReferenceNEI August 2012)
NRC JLD-ISG-2012-06,     "Guidancefor Performinga Tsunami,Surge or SeicheFlooding HazardAssessment",Revision0, dated January4, 2013 (ReferenceJ LD-lSG-2O         12-06)
     . NRC JLD-lSG-2013-01,"Guidancefor Assessmentof Flooding Hazards due to Dam Failure",Revision0, datedJuly 29, 2013 (ReferenceJLD-lSG-2013-01)
The flood hazardreevaluation,   includinginputsand methodology,are beyondthe currentPNPP design and licensebasis.Consequently,the analyticalresultsprojectbeyondthe capabilityof the current design basis. The following provides the flood-causingmechanismsand their associatedwater surfaceelevationsthat are consideredin the PNPP flood hazard reevaluation.
3.1. Flooding in Streams and Rivers (ReferencePNPP 2015a,PNPP 2015b, PNPP 2015c, PNPP2015i,PNPP2015n,PNPP 2015o,PNPP2015p,and PNPP2015q)
The updateddesignbasisanalysesincorporated       the beyonddesignbasisevents.Therefore,the beyonddesignbasisanalysesare identicalto the updateddesignbasisanalysesfor the Major Stream,the MinorStream,and the DiversionStream.The PMF in riversand streamsadjoining the site is determinedby applyingthe PMP to the drainagebasin in which the site is located.
Becausethe watershedsanalyzedare small,the representative     PMP is pointprecipitation.
The PMF is basedon a translationof PMP rainfallin the watershedto flood flow. The PMP is a deterministicestimateof the theoreticalmaximumdepth of precipitationthat can occur at a certaintime of year for a specifiedarea at a particulargeographicallocation.A rainfall-to-runoff transformation                                           basedon the topographicand drainage function,as well as runoffcharacteristics, system networkcharacteristicsand watershedproperties,are neededto appropriatelydevelop the PMF hydrograph.The PMF hydrographis a time historyof the dischargeand servesas the inputparameterfor other hydraulicmodelsthat developthe flow characteristics,   includingflood flow and elevation.
PERRYNUCLEARPOWERPLANT                                                              Page 15 of 42

NTTF Recommendation     2.1 (HazardReevaluations):  Flooding                            Revision1 FirstEnergyCorporation                                                               March2,2016 The PMF is a functionof the combinedeventsdefinedin NUREG/CR-7046          for floodscausedby precipitationevents.Cool-seasonalternativesare determinedto be boundedby the all-season alternative.
Alternative1 - Combinationof:
       . Mean monthlybaseflow
       . Mediansoil moisture
       . Antecedentor subsequentrain:the lesserof (1) rainfallequalto 40 percentof PMP and (2) a 500-yearrainfall
       . The All-SeasonPMP
       . Waves inducedby 2-yearwind speedappliedalongthe criticaldirection Alternative2- Combination   of:
o  Mean monthlybaseflow
       . Snowmeltfrom the probablemaximumsnowpack
       . A 1O0-year, snow-seasonrainfall o  Waves inducedby 2-yearwind speed appliedalong the criticaldirection Alternative3 - Combinationof.
o  Mean monthlybaseflow o  Snowmeltfrom a 1OO-year    snowpack o  Snow-seasonPMP
       . Waves inducedby 2-yearwind speedappliedalongthe critical 3.1.1. Basis of Inputs:
The inputsused in the PMP and PMF analysesare basedon the following:
All-SeasonPMPAnalysis o PNPP,MajorStream,MinorStream,and DiversionStreamwatershedlocations;
          . ProbableMaximumPrecipitation      Studyfor the Stateof Ohio; o Site-specific,all-seasonPMP pointrainfallshort durationestimatesdeterminedusing a storm-basedapproach in accordancewith National Oceanic and Atmospheric Administration(NOAA) Hydrometeorological      Reportsand the World Meteorological Organizationapproach; o UncorrectedHydrometeorological     ReportNo. 33 PMP pointrainfallestimates;
          . Hydrometeorological    ReportNo. 52 ratiosfor PMP point rainfallestimatesfor durations less than t hour.
PMF Analysis-Hydrologicand HydraulicAnalysis
          . PNPP, Major Stream, Minor Stream, and DiversionStream watershed areas,boundariesand configurations; o Precipitationfor the subjectwatershedarea;
          . Baseflow:Historicflowratedata collectedby USGSatgauge 04212100on the Grand River,which is used to determinethe base flow for the Major Stream,MinorStream, and DiversionStream; PERRYNUCLEARPOWERPLANT                                                               Page 16 of 42

NTTF Recommendation      2.1 (HazardReevaluations):    Flooding                           Revision1 FirstEnergyCorporation                                                                March2,2016 a  Sitetopographydevelopedfrom aerialphotogrammetry; a  Digitalterrainmodel(DTM)developedfrom site topography; a  Manning's roughness coefficientsare based on a visual assessment of aerial photography   and selectedusingstandardapplicableengineeringguidancereferences; and a  Site data for the rail line bridgecrossingthe MajorStream; a  Construction   drawingsand as-builtdrawingsfor modifications  to the MajorStreamrail line embankment,the secondaryplantaccessroad,and the DiversionStream.
3.1.2. Gomputer Software Programs PMP o   ArcGlSDesktop10.1
           . MicrosoftExcel2007 and 2013 PMF analysis
           . AutoCADCivil 3D 2012
           . ArcGlSDesktop10.0 o   ArcGlSDesktop10.1
           . HEC-HMS3.5
           . HEC-RAS4.1
           . HEC-GeoRAS10.1
           . MicrosoftExcel2010 and 2013 3.1.3. Methodology The site-specific  PMP analysisincludedthe followingsteps:
           . An extensivestorm searchto identifystormswhich could be used for PMP studiesin the region.
           . Largest precipitationevents which were determinedto be transpositionableto the PNPPsite were then maximizedin-placeand transpositioned       to the site.
Site-Specific,All-Season PMP All the storms evaluatedin the previousPMP studiesin the region,and consideredto be transpositionable   to the PNPP site were evaluated.This resultedin 20 events that were evaluatedto determinethe shortduration1-hourdepthfor the site-specific,       all-seasonPMP.
Ten of these storms were previously analyzedin Hydrometeorological         Report No. 33 and Hydrometeorological     Report No. 51 (ReferenceNOAA 1978) by the National Weather Service(NWS)and the USACE.The remaining10 were analyzedfor the ProbableMaximum Precipitation Studyfor the Stateof Ohio.
Eachstormis then maximizedby an in-placemaximization       factorto representwhat the storm would have looked like had the atmosphericconditionsand moistureavailablefor rainfall productionbeen at maximum levels when the storm occurredversus what was actually observed.The in-placemaximizedvaluesfor each stormare then adjustedto transposethe storm from its originallocationto the PNPP site. The transpositioncalculationadjustsfor ditferencesin availablemoistureat the site versus the originalstorm location.The ratiosto determinesub-hourlyincrementsin Hydrometeorological        ReportNo. 52, are appliedto the resultingsite-specific,1-hourPMP estimateto determine5-, 15-, and 3O-minuteduration estimates.
PERRYNUCLEARPOWERPLANT                                                                Page 17 of 42

NTTF Recommendation     2.1 (HazardReevaluations):   Flooding                         Revision1 FirstEnergyCorporation                                                            March2.2016 The PMF analysisincludesthe followingsteps:
           . Delineatewatershedand sub-watershedsand calculatesub-watershedareas for inputintothe USACEHEC-HMSrainfall-runoff      hydrologiccomputermodel.
o Determinerainfall.
           . EstimateHEC-HMSrainfall-runoff      model input parameters:NRCS unit hydrograph method.
           . Adjust unit hydrographto accountfor the effectsof nonlinearbasinresponse.
           . PerformPMF simulationwith PMP inputusingHEC-HMSmodelwith no precipitation losses.
           . Estimatewater surface elevationusing HEC-RASunsteady-statemodel by using runotfhydrographfrom the HEC-HMSmodelas an input.
Watershed Delineation For the purposesof the hydrologicmodelingeffort,the MajorStreamis evaluatedusingone watershed.The MinorStreamwatershedis subdividedintothree(3) sub-watersheds         (a small area southof the site,the MinorStreamand site areacontributing   to the MinorStreamat the lateralswalebetweenthe two coolingtowers,and the small remainingarea of the unnamed tributaryeast of the securitybarriers)based on the topographyof the site. The Diversion Streamis evaluatedusing one watershed.
All-SeasonPMP For the Major Streamanalysis,the all-seasonPMP is determinedby usingthe site-specific PMP estimatesdefinedby the PMP studyfor the Stateof Ohio (ReferenceODNR 2013)for durationsfrom 6to72 hours.The PNPPsite-specific      analysisdefinesthe PMP estimatesfor t hour and sub-hourlyincrements.IntermediateS-minuteincrementalPMP depths are determinedfor pointprecipitation  (1 squaremile).
As a boundingapproach,the Minor Stream and DiversionStream are modeledusing the UncorrectedHydrometeorological     Report No. 33 all-seasonPMP. Hydrometeorological ReportNo. 33 definesPMP estimatesfor durationsfrom t hourto 48 hours.Ratiosprovided by HydrometeorologicafReport No. 52 are used to define the sub-hourly increments.
IntermediateS-minuteincrementalPMP depths are determinedfor point precipitation(1 squaremile).
The temporaldistributionof the PMP is arrangedin accordancewith the recommendations in Hydrometeorological   Report No. 52, wherein individualrainfall incrementsdecrease progressivelyto eitherside of the greatestrainfallincrement.Varioustemporaldistributions for each rainfallscenarioare then evaluatedto furthermaximizethe runoff.Front,one-third, center, two-thirds,and end-loadingtemporaldistributionsare consideredin an effort to capturethe distributionthat maximizesrunoff.
Note that an antecedentrainfalloccurs prior to the all-seasonPMP. Becauseof the small drainageareasof the MajorStream,MinorStream,and DiversionStreamand the dry period betweenthe antecedentstorm and the PMP event,the streamsreturnto baseflowconditions priorto the PMP event. Therefore,the antecedentstorm is determinedto have no influence on the PMP storm.
HydrologicModel (HEC-HMS)
The PMF is the flood resultingfrom the all-seasonPMP. USACE HEC-HMS hydrologic software is used to convert rainfallto runoff.A rainfallhyetographis applied to the Major Streamwatershed,the DiversionStreamwatershed,and each sub-watershedof the Minor PERRYNUCLEARPOWERPLANT                                                            Page 18 of 42

NTTF Recommendation     2.1 (HazardReevaluations): Flooding                             Revision1 FirstEnergyCorporation                                                              March2,2016 Stream and transformedto runoff using unit hydrographmethodology.Generally,a unit hydrographis developedusinghistoricaldata obtainedfrom variousrain and streamgauges in the watershed.The Major Stream,Minor Stream,and DiversionStreamwatershedsare ungauged.Thus, no historicalobservationsare availableto use as a basisto createa unit hydrograph.Therefore,a syntheticunit hydrographis developed.NRCS unit hydrograph methodologyis usedfor rainfall-to-runofftransformation.
ANSI/ANS-2.8-1992     suggeststhat base flow should be based on mean monthlyflow. As mean monthlyflow is not availablefor the MajorStream,MinorStream,or DiversionStream, the base flow is approximatedbased on the mean monthlyflow in an adjacentwatershed.
The USGSgaugestationon the GrandRivernearPainesville,        OH is used.The GrandRiver has the same hydrologicunit code accountinglevelas the MajorStream,MinorStream,and DiversionStreamand are adjacenthydrologicunitcodesub-watershed          levels.Therefore,the riversand streamsexhibitsimilarwatershedcharacteristics,   and it is an acceptableapproach to use the base flow informationfor the Grand Riveras the basisfor estimationof the base flow for Major Stream,Minor Stream,and DiversionStream.
To conservativelymaximize runoff, f,o               losses are                  into the seasonPMF alternativeanalysis.
The unit hydrographsfor the Major Stream watershed,each sub-watershedof the Minor Stream,and the DiversionStreamare modifiedto accountfor the effectsof nonlinearbasin response in accordancewith NUREG/CR-7046.The peak of each unit hydrographis increased by one-fifth and the time-to-peak is reduced by onethird. The remaining hydrographordinatesare adjustedto preservethe runoff volume to a unit depth over the drainagearea.
The area betweenthe rail line spur and the secondaryaccess road in the overbankon the northeastside of Major Streamwould be subjectto the effectsof localizedPMP rainfall.The area is evaluatedusinga HEC-HMSlevel-poolstorageroutingmodel.The samesite-specific PMP is appliedto the model.No fossesare incorporatedinto the analysis.Dischargefrom the area is determinedbasedon weir flow over the rail line.
HydraulicModel (HEC-RAS)
The unsteadyflow simulationmodule within the USACE HEC-RASsoftware is used to transformthe resultingflow hydrographsfrom the controllingalternativeinto a water surface elevationhydrographunderunsteadyflow conditions.
Channeland floodplaingeometryfor the MajorStream,the MinorStream,and the Diversion Stream is modeled by developingcross sections of the streams. The cross sections are placedat locationsthat definegeometriccharacteristicsof the streamand overbanks.Cross sectionsare also placedat representative locationswherechangesoccurin discharge,slope, shape,and roughness,as well as at hydraulicand inlinestructures(e.9.,bridgesculverts).
Streambanks,blockedobstructions,and ineffectiveflow areas are also incorporatedinto the HEC-RASmodel.
The cross sections of the Major Stream reflect the removal of a portion of the rail line embankment.Three crossingsare incorporatedinto the Major Stream model. The plant access road includesa culvertand is modeledusing topographicsurvey data and USAR data. The upstream rail line bridge is modeled using topographicsurvey data and site records.The upstreamsecondaryaccessroad is includedas an inlinestructureand all flow overtopsthe road.
PERRYNUCLEARPOWERPLANT                                                               Page 19 of 42

NTTF Recommendation      2.1 (HazardReevaluations):  Flooding                        Revision1 FirstEnergyCorporation                                                          March2,2016 One crossingis incorporated  intothe MinorStreammodel.The downstreamLockwoodRoad crossingis modeledas an inlinestructureand all flow overtopsthe road.The culvertat the outfallof the DiversionStreamis assumedto be completelyblockedand modeledas an inline structure.
The PMF flow hydrographsobtainedfrom the time-seriesoutflowresultsof the HEC-HMS modelsare enteredinto the HEC-RASmodels.A boundingwater level in Lake Erie is used as a downstreamboundaryconditionfor the HEC-RASsoftwareprogram.
The DiversionStreambermwas assessedfor failureand the potentialfor impacton the Minor Stream results.Failureof the berm is assumedto occur during the peak water surface elevationin the DiversionStream,ata locationthat maximizesthe depth.Becausethe berm crest does not overtopduringthe PMF, pipingfailureis consideredto be the failuremode.
No tailwateris assumedfor the analysis.Breachparametersare selectedin accordancewith JLD-ISG-2013-01to maximizethe breach and the resultingfailureftow hydrograph.The HEC-RAS models used to evaluatethe effects of the PMF are used to assess the failure effects. The berm failure is modeled as a lateral breach in the HEC-RAS model for the DiversionStream.The resultingfailureflow hydrographis then addedto the HEC-RASmodel for the Minor Stream. The HEC-RAS models are evaluated using unsteady-stateflow simulation.
3.1.4. Results MaiorStream The Major Stream is not directlyadjacentto PNPP safety-relatedstructures.The analysis does not resultin overtoppingof the raillinebridgestructure.MajorStreamfloodingupstream of the rail line is preventedfrom encroachingon adjacentareas in the overbankon the northeastside by the elevatedembankmentof the raillinespur.The raisedsecondaryaccess road is also not overtoppedby the localizedfloodingof the area betweenthe rail line spur and the secondaryaccessroad.Therefore,the MajorStreamdoes not contributeto flooding effectsin the Minor Stream,the DiversionStream,or the power block area. The one-third, center,and two-thirdstemporaldistributions  produceidenticalpeakresultsand the maximum water levels.The maximumwater surfaceelevationat the rail line bridgestructureis 628.5 feet Perry Local Datum, with a maximum flow of 34,200 cfs at the bridge. The resulting maximum water levels for the Major Stream are not adjacent to the power block. The maximumwater surface elevationproducedfor the area in the overbankon the northeast side of MajorStreambetweenthe rail line spur and the secondaryaccessroad is 631.4feet Perry Local Datum. The secondaryaccess road was raisedto exceed the maximumwater surface elevationas part of the modificationsperformedin 2015. Therefore,overflowfrom the area is maintainedwithin the Major Stream watershed.As previouslyindicated,the updateddesignbasisanalysesincorporated      the beyonddesignbasisevents.Therefore,the beyonddesignbasisresultsfor the MajorStreamare identicalto the updateddesignbasis.
MinorStream The one-third,center,and twothirds temporaldistributionsproduceidenticalpeak results and the maximumwater levels.The maximumwater surfaceelevationoccursat the Unit 2 Turbine Buildingand is 619.7 feet Perry Local Datum. The maximum flow overtopping LockwoodRoad downstreamis 1,100 cfs.
The maximumwater surfaceelevationsat each safety-relatedstructureadjacentto the Minor Streamfloodingare providedin Table 4. As previouslyindicated,the updateddesign basis PERRYNUCLEARPOWERPLANT                                                           Page 20 of 42

NTTF Recommendation      2.1 (HazardReevaluations):  Flooding                         Revision1 First EnergyCorporation                                                             March2,2016 analysesincorporatedthe beyonddesignbasisevents.Therefore,the beyonddesignbasis resuftsfor the MinorStreamprovidedin Table4 are identicalto the updateddesignbasis.
Table 4 - Minor Stream Beyond Design Basis Flooding Elevations and Durationsat PNPP Maximum Water           FloodDurationabove Surface Elevation (feet      620.5feet (Perry Structure            Perry Local Datum)           LocalDatum)
Unit2 TurbineBuilding                619.7                      nla Unit2 AuxiliaryBuilding              619.4                      nla Unit2 ReactorBuilding                618.9                      nla Intermediate Building                618.9                      nla Unit 1 ReactorBuilding               618.9                      nla Unit1 AuxiliaryBuilding              618.9                      nla Unit1 TurbineBuilding                618.7                      nla DiversionStream The one-third,center,and twothirds temporaldistributionsproduceidenticalpeak results and the maximumwater levelsfor the DiversionStream.The PMF inflowhydrographhas a peak of 4,200 cfs. The maximumwater surfaceelevationoccursat the upstreamfill area and is 629.2feet Perry Local Datum.The fill area and berm are designedwith a crestelevation of 630.9 feet Perry Local Datum. The berm constructedadjacent to the stream prevents floodingof the site.
Failureof the DiversionStreamberm resultsin a failureflow hydrographwith a peak of 670 cfs addedto the Minor Streammodeling.Becauseof the differencein responsetimes for the MinorStreamand the DiversionStream,the additionof the failureflow hydrographextends the durationof flooding in the Minor Stream, but the peak water surface elevationsare identicalto the PMFfloodingidentifiedin Table4. As previouslyindicated,the updateddesign basisanalysesincorporatedthe beyonddesignbasisevents.Therefore,the beyonddesign basisresultsfor the DiversionStreamare identicalto the updateddesignbasis.
3.2. Dam Assessment (ReferencePNPP 2015d) 3.2.1. Basis of Inputs Inputsused for the dam assessmentevaluation
            . PNPP,MajorStream,and MinorStreamwatershedlocations.
            . USGStopographic   quadranglemaps.
o   The USACE NationalInventoryof Dams (NlD) database used to identify any watersheddams.
3.2.2. Gomputer Software Programs
            . None PERRYNUCLEARPOWERPLANT                                                              Page 21 of 42

NTTF Recommendation       2.1 (HazardReevaluations):Flooding                         Revision1 FirstEnergyCorporation                                                            March2.2016 3.2.3. Methodology The PNPP Major Stream, Minor Stream, and DiversionStream watershed locationsare approximatedusing USGS topographicquadranglemaps. The USACE NID databaseis reviewedto determinethat no dams are located in the Major Stream, Minor Stream, or DiversionStreamwatersheds.
3.2.4. Results No dams are locatedin the combinedwatershedof the Major Stream,Minor Stream,and DiversionStream.Therefore,dam failureis not applicable.
3.3. lce-lnducedFlooding(ReferencePNPP2015e)
As identifiedby NUREGICR-7046,icejams and ice damscan form in riversand streamsadjacent to a site, and may leadto floodingby two mechanisms:
o   Collapseof an icejam or an ice dam upstreamof the site can resultin a dam breach-like flood wave that may propagateto the site; and
       . An ice jam or an ice dam downstreamof a site may impoundwater upstreamof itself, thus causinga flood via backwatereffects.
3.3.1. Basis of Inputs
           . USACEice jam database.
o   Site topography.
o   Bridge geometry (upstream and downstream of PNPP) determined using site topographyand site records.
3.3.2. Computer Software Programs
           . MicrosoftExcel 2013 3.3.3. Methodology Per NUREG/CR-7046,ice-inducedfloodingis assessedby reviewingthe USACE ice jam databaseto determinethe most severe historicalevents that have occurred.No historical records are availablefor the Major Stream, Minor Stream, or DiversionStream. The nonexistenceof ice jam recordsis explainedby the absenceof streammonitoringstations on the two streams. Based on ice jam occurrences recorded for rivers within adjacent watersheds,it is determinedthat ice jam eventsare possible.
The maximum ice jam is determinedby selectingthe historicevent that producedthe maximum flood stage relative to the normal water surface elevation at that location.
Regardlessof the specificconditionsthat producedthe historicflood stage at a specific assumedto representthe ice jam.
location,the full heightis conservatively Historicalice jam data for the adjacentwatershedsfor the Grand River and the Ashtabula Riverare considered.Althoughno recordsare availablefor the actualheightof the ice jams, the maximumrecordedstage is used to representthe ice jam. The ice jam is transposedto the site and comparedwith otherfloodingcausingmechanisms.
3.3.4. Results The maximumreportedice jam stage in the regionalvicinityof PNPP is estimatedto be 18 feet. For the MinorStream,no significantupstreamcrossingsor structuresare presentthat PERRYNUCLEARPOWERPLANT                                                            Page 22 of 42

NTTF Recommendation     2.1 (HazardReevaluations):  Flooding                           Revision1 FirstEnergyCorporation                                                             March2.2016 couldfacilitatesignificantice jam formation.The only upstreamaccessroad is now located in the DiversionStreamwatershed.The accessroadis an unimprovedroadwith a low profile and a small drainagestructure.The elevationcharacteristics    of the area at that drainage structureindicatein the unlikelyeventan ice jam did occur,it would be limitedto less than 2 feet in height.Furthermore, any icejam and subsequentfailurewouldonly releasea flow rate at the maximumcapacityof the smalldrainagestructure.By qualitativecomparison,the PMF analysisincludesrainfallrunoffcontributionfrom the entiredrainagearearesultingin a peak flow rate magnitudesgreaterthan the capacityof a small drainagestructure.Any upstream icejam collapseis boundedby the PMF analysis.
The only downstreamlocationon the MinorStreamconduciveto an ice jam is at Lockwood Road.The assumedtransposition      of the maximumicejam would producea maximumwater surfaceelevationof 608.9 feet Perry Local Datum.Assumingthe culvertat LockwoodRoad is completelyblocked,any coincidentflow would eventuallyovertopLockwoodRoad. The PMF analysisfor MinorStreamassumesthe LockwoodRoad culvertis completelyblocked and the PMF overtopstheroad.Therefore,by qualitativecomparisonwith the PMF analysis, any downstreamice jam floodingis boundedby the PMF analysis.
Downstreamice jam floodingwas not specificallyexaminedfor the DiversionStream. The DiversionStreamis locatedeast of the Minor Streamand is not adjacentto the immediate area of the plant.Similarto the Minor Stream,the downstreamend of the DlversionStream also has a culvert.Assumingthe culvertis completelyblocked,any coincidentflow would eventuallyovertopthe culvertembankment.The culvertembankmentis significantlylower than the berm locatedbetweenthe DiversionStreamand the site.
For the MajorStream,the upstreamrail line bridgehas a clearheightof greaterthan 20 feet from naturalgradeto the bottomof the low chord.The assumedtransposition    of the maximum estimated18 feet ice   jam would allow normalflows overtoppingthe ice   jam to flow through the remainingbridgeopeningbelowthe low chord.In addition,flow would pass throughthe removedportionof the abandonedrail line embankmentto the southwestof the rail line bridgecrossingthe Major Stream.Any ice jam failureat this locationwould be transposed downstreamto the plant accessroad.
The accessroadincludesa largeellipticalculvert35'-11" by 23'-5".Basedon sitetopography the clearheightis approximately18 feet abovethe normalwatersurfaceelevation.Assumed transpositionof the maximumestimated18 feet ice jam would producea maximumwater surfaceelevationbelowthe plantaccessroad.Assumingthe culvertat the plantaccessroad is completelyblocked,any coincidentflow would eventuallyovertopthe plant accessroad.
The PMF analysis for Major Stream results in overtoppingof the plant access road.
Therefore,by qualitativecomparisonwith the PMF analysis,any ice jam floodingis bounded by the PMF analysis.
The downstreamsedimentcontrolstructureis the only other locationpossiblyconduciveto an ice jam. The assumedtranspositionof the maximumice jam would producea maximum water surfaceelevationof 604.9feet Perry Local Datum.The resultsof the PMF analysesfor the Major Streamexceedthe estimatedice jam elevation.
lce-inducedfloodingat PNPPis boundedby the PMF analyses,and no furtherconsideration is required.
PERRYNUCLEARPOWERPLANT                                                             Page 23 ol 42

NTTF Recommendation       2.1 (HazardReevaluations):  Flooding                                Revision1 FirstEnergyCorporation                                                                     March2,2016 3.4.GhannelMigrationor Diversion(ReferencePNPP2015e)
NUREG/CR-7046        indicateshistoricalrecordsand hydrogeomorphological         data shouldbe used to determinewhetheran adjacentchannel,stream,or riverhas exhibitedthe tendencyto migrate towardsthe site.
3.4.1. Basis of Inputs o    Ohio Departmentof NaturalResourcessurficialgeologymap (ODNR2006) o    USGS topographicquadranglemaps, includingaerial images (ReferenceUSGS 1943,USGS 1992,USGS1994,and USGS2010) 3.4.2. Computer Software Programs
            . None 3.4.3. Methodology Surficialgeologyalong with historicand currenttopographicquadranglemaps that include aerial images are reviewedto examinethe conditionand alignmentof riversand streams over time.
3.4.4. Results The surficial geology map indicates the area in the immediate vicinity of PNPP is characterizedby layersof sand, silt and clay, and till or clayeyto silty till over shale bedrock.
This characterizationrepresentsthe entirewatershedof the Minor Stream and the majority of the Major Stream.The upstreamportionof Major Stream is characterizedby additional areasof sandand gravelor clayeyto siltytill overshalebedrock.Alluviumor organicmaterial, whichare moresusceptibleto erosion,are not presentin the MajorStream,the MinorStream, or DiversionStreamwatersheds.
Topographicmaps for the yearsof 1905 (Reprinted1943),1960 (Revised1992),1994,and 2010 are reviewedto assess historicchannelmigration.The Minor Streamwas reroutedas part of the plantconstruction.In 2015 site modifications   constructedthe DiversionStreamto divert runoff flow upstream of the Minor Stream, east around the outside of the security barriers,and north directlyto Lake Erie. The topographicand aerial images provide no evidenceof oxbows, braidedstreams,or alluvialfans that could indicatea potentialfor channelmigrationof the MajorStreamor the Minor Stream.The DiversionStreamis newly constructedand does not exhibitevidenceof a potentialfor channelmigration.The Diversion Stream is locatedeast of the Minor Streamand is not adjacentto the immediatearea of the plant.
The streamsin the vicinityof PNPPdo not exhibitcharacteristics     of channelmigration.
3.5.Storm Surge (ReferencePNPP20151,PNPP20159,PNPP2015h,PNPP2015k,and PNPP2015t)
Probable Maximum Storm Surqe (PMSS) fn accordancewith JLD-ISG-2012-06,      all coastalnuclearpower plant sites and nuclearpower plant sites adjacentto cooling ponds or reservoirssubject to potentialhurricanes,windstorms and squall lines must considerthe potentialfor inundationfrom storm surge and waves.JLD-ISG-2012-06also suggeststhat for the storm surge hazardassessment,historicalstorm events in the regionshouldbe augmentedby a syntheticstormparameterized           to accountfor conditions PERRYNUCLEARPOWERPLANT                                                                     Page 24 of 42

NTTF Recommendation      2.1 (HazardReevaluations):   Flooding                          Revision1 FirstEnergyCorporation                                                              March2,2016 moreseverethanthosein the historicalrecordsand consideredreasonablypossibleon the basis of technicalreasoning.
3.5.1. Basis of Inputs The inputsused in PMSSanalysisare basedon the following:
           . Historicalwind and pressurefield data from NOAAfor the Great Lake Region
           . Probablemaximumwindstorm(PMWS)
           . Lake Erie bathymetryfrom the NOAAgeophysicaldatabase
           . SupportingGIS data 3.5.2. Computer Software Programs
           . ArcMap10.1
           . Delft3D software suite (Delft3D-FLOWRevision 1, Delft3D-WAVERevision 0, Delft3D-RGFGRID      Revision1, and Delft3D-QUICKIN Revision1) o   lGLD85HeightConversionTool o   R ComputerLanguage2.15.1
           . MicrosoftExcel2007,2010,and 2013 3.5.3. Methodology Severalphysicalprocessescontributeto the generationof a stormsurge.The contributionof wind to a stormsurgeis oftencalledwind setup.Wind blowingoverthe watercausesa shear stressthat is exertedon the surfaceof the water, pushingwater in the directionof the wind.
Atmosphericpressuregradientsare anotherforcingmechanismthat contributesto changes in water level, as water is forced from regionsof high atmosphericpressuretoward regions of low atmosphericpressure.
The followingdescribesthe methodologies     used in the PMSScalculation:
Development of the PMWS The PMWS storm-basedapproachis specificto the characteristicsof the site. Past extreme events in a region are analyzedand consideredtranspositionable.      As part of the PMWS, differentstormtypes(suchas synoptic,squallline,and hybrid)that impactedthe GreatLakes regionare consideredin orderto determinethe stormeventthat will generatethe maximum surge and seiche.Each storm'sinput parametersare quantifiedand plottedbased on the locationof low/highpressurecenters,concurrentwind/pressurefields, and how they evolve throughtime and space.
Most of the synopticstormsoccur in associationwith deep areasof low pressurewhich move throughthe regionfrom southwestto northeast.The generalsynopticpatternis one in which the deep area of low pressureresults in a very strong pressuregradientforce between its low pressurecenterand a correspondingregionof higherpressureto the north or west. The larger the gradient between the two systems over a given distance is, the stronger the resultingwinds.
Squallline (or derecho)eventscreatea widespreadstraight-line    windstormthat is associated with a fast-movingband of severethunderstorms.These winds have producedsome of the highestinstantaneous   gustson record,but lastfor only a shorttime (lessthan 30 minutes)at a givenlocation.The shortdurationof theseevents,as they quicklytraversea givenlocation, means they will not controlthe PMSS. Further,these eventsdo not occur within deep low pressuresystemsor remnanttropicalsystems.Therefore,their wind and pressuredata are PERRYNUCLEARPOWERPLANT                                                              Page 25 of 42

NTTF Recommendation     2.1 (HazardReevaluations):  Flooding                           Revision1 FirstEnergyCorporation                                                            M a r c h2 , 2 0 1 6 not combinedwith the otherstormtypes in this analysis,as this would resultin a PMWSthat is not physicallypossible.
Althoughdeep low pressuresystemsoften producethe longestdurationlarge-scalewinds, other storm types also produce strong winds over the region. ln rare cases, land-falling tropical systems along the Gulf Coast or Atlantic Seaboard move inland across the Appalachiansor up the Mississippiand Ohio Rivervalleys.By the time these stormsreach the Great Lakes region,they are no longertropicalsystems,but insteadhave transitioned into extra-tropicalcyclones.Their general circulationand center of deep low pressure persists. Much like the deep low pressure scenario previouslydiscussed,strong and persistentwindscan result.The remnantsof HurricaneHazel(October1954)and Hurricane Sandy (October2012) are classicexamplesof this stormtype. This storm scenarioprovided some of the strongestwinds from the northwestthroughthe northeastdirectionsover Lake Erie (withdurationsof 12 hoursor more).
Delft3DGalibration The Delft3Dhydrodynamicmodelis set up usingthe Delft3Dsoftwaresuite.The wave setup contribution to the total stormsurgevaluesare modeledby couplingthe Delft3D-WAVEand Delft3D-FLOW    surge models.The generalapproachto stormsurge modelingusingcoupled Delft3D-FLOWand Delft3D-WAVEmodelsconsistsof the followingsteps:
      . Developingthe bathymetricdatasetand modelgrid mesh for the lake system;
      . Assemblinginputfilesfor atmosphericforcing(windand pressurefields);
Assemblinginputfilesfor initialwater level,boundaryconditions,and the physicaland numericalparametersof the model; Assemblingmeasuredwater levelsand wave data for modelcalibrationand verification; Testingand refiningthe initialmodelsetup; Validatingthe model for historicalextremestorm events;and Assessingmodel sensitivityto variousfactorsand adjustableparameterssuch as bottomfrictionand wind drag coefficient.
The Delft3Dmodelis calibratedbasedon historicaldata obtainedfrom NOAA meteorological and water levelrecordingstationslocatedin the Lake Erie region.
Reviewof historicaldata showsthat variouspartsof Lake Erie responddifferentlyto any one particularstorm.The stormthat producesextremewater levelsin one part of Lake Erie might not, and probablydoes not, produceextremelevelsin other parts.Thereforethe numberof calibrationand validationstormsselected,to assessmodelpredictionaccuracy,coveredall partsof the lake shoreline.
Calibrationand verificationof the coupled Delft3D-FLOWand Delft3D-WAVEmodels is performedby a time series comparisonof measuredand predicted/modeledstorm surge values at different water level recordingstations on Lake Erie. A similar time series comparisonis also performedfor wave heights.
The Delft3D models are calibratedusing extreme historicwind and pressuredata from multiplemeteorological   and water levelrecordingstations.Calibrationand verificationof the coupled Delft3D-FLOWand Delft3D-WAVEmodels demonstratesthat the hydrodynamic model is capableof computingthe stormsurge and seichedynamicsfor Lake Erie,as well as the significantwave heightsand periodsat PNPPfrom PMWS events.
PERRYNUCLEARPOWERPLANT                                                            Page 26 of 42

NTTFRecommendation       2.1 (HazardReevaluations):  Flooding                           Revision1 FirstEnergyCorporation                                                              March2,2016 PMSS The calibratedDelft3Dmodelis usedto determinethe PMSS.The historicwind and pressure field data is replacedwith candidatePMWS events,and the model is run to determinethe criticalPMWS.
JLD-ISG-2012-06     and ANSI/ANS2.8-1992requirethe antecedent(pre-storm)water level equalto the 1OO-year    maximumrecordedwater levelto be appliedas the initialstormsurge modelstillwater level.The 1OO-year   water levelof 575.8feet PerryLocalDatum(574.6feet IGLD 85) is used as the initialcondition/antecedent   water level in all the Delft3D-FLOW models.Sincethe probableminimumlow water levelat PNPP couldoccurat a time when the monthlymean lake level is at the long-termmean low probablelevel,the antecedent water level for low water evaluationis set to the long-termlow probablelevelat Lake Erie, which is equalto 569.2feet PerryLocalDatum(568feet IGLD 85).
Varioustopographicfeaturesaffectthe storm surge propagationtowardsPNPP.The site is locatedon the bluffsadjacentto the shoresof Lake Erie. The bluffsat the site are more than 40 feet abovethe 100-yearwater levelof the lake.
Maximum Historical and 2S-yearStorm Surge The historicalmaximumstorm surge is the largestof the determinedyearly maximumstorm surge heights.The historicalmaximumstorm surge height is used in combinedflooding scenariosas discussedin Section3.7.
Storm surgesare calculatedfrom monthlydata as the differencebetweenmonthlymaximum and monthly mean based on guidance providedby USACE. The Log PearsonType lll distributionis the commonlyacceptedfrequencyprocedurefor annualmaximumwaterlevels.
A frequencyanalysison the yearlymaximumstormsurge heightsobtainedfrom the Fairport and Eriestationsis performedusinga Log Pearsonlll statisticalanalysis.The 2S-yearstorm surge heightis used in combinedfloodingscenarios.
3.5.4. Results Simulationsof all the candidatePMWS eventsshowedthat the criticalPMWS event is the transpositionedSeptember1989wind stormevent maximizedover the PNPP site.This storm is the most intenseof all the PMWS eventswith a maximumwind speed of 106 miles/hour and is aligned along the north-southdirection.The maximum PMSS resultingfrom this PMWS event produceda maximumwater surfaceelevationof 582.8feet PerryLocal Datum, which is well below the site. Wave runup effects are evaluated with combined flooding scenariosas discussedin Section3.7.
Surge, Seiche, and Resonance Resultsshow that the levelof the rise due to a seicheis significantly lessthan the calculated surge height.For this reason,seichesare not the controllingflood eventat PNPP.
Resonancegeneratedby waves can cause problemsin enclosedwater bodies such as harborsand bays when the periodof oscillationof the water body is equal to the periodof the incomingwaves. However,the PNPP site is not located in an enclosedembayment.
Additionally,the periodof oscillationof Lake Erie near the PNPP site is determinedto be in the rangeof 11 to 15 hours.This is muchgreaterthan that of the peak spectralperiodof the incidentshallowwater storm waves. Consequently,resonanceis not a detrimentat PNPP duringthe criticalPMWS event.
PERRYNUCLEARPOWERPLANT                                                              Page 27 of 42

NTTF Recommendation     2.1 (HazardReevaluations): Flooding                        Revision1 FirstEnergyCorporation                                                         March2,2016 Probable Minimum Low Water Level resulting from the PMWS Simulationsof all the candidatePMWS stormeventsshow that the criticalPMWS eventthat would result in probable minimum low water level (drawdown)is the transpositioned November1998stormeventmaximizedoverthe PNPPsite.Thisstormhad the most intense southeasterlywinds of the examinedstorm events, with a maximum wind speed of 93 miles/hour.The probableminimum low water elevation(drawdown)associatedwith the transposedNovember1998 storm producesa probableminimumlow water level of 563.2 feet Perry Local Datum near the PNPP site. The invertsof the PNPP intake ports are at an averageelevationof 552.65feet PerryLocalDatum(USAR2.4.11.2.2.2).
3.6. Tsunami Assessment (ReferencePNPP 2015i)
NUREG/CR-6966identifiesthat earthquakes,landslides,and volcanoescan initiatetsunamis, with earthquakesbeing the most frequent cause. Dip-slip earthquakes(due to vertical movement)are more efficientat generatingtsunamis than strike-slipearthquakes(due to horizontalmovement).To generatea major tsunami,a substantialamount of slip and a large rupturearea is required.Consequently, only largeearthquakeswith magnitudesgreaterthan 6.5 generateobservabletsunamis.
3.6.1. Basis of Inputs
           . NationalCenterfor EarthquakeEngineeringResearch(NCEER)database
           . NaturalResourcesCanadaseismicitydata o   NOAA naturalhazardstsunamidatabase o   NOAA naturalhazardsvolcanodatabase o  Ohio Departmentof NaturalResources(ODNR)seismicitydata
           . USGSearthquakehazardsprogramdatabase 3.6.2. Gomputer SofhrvarePrograms
           . None 3.6.3. Methodology As identifiedby NUREGICR-7046,tsunami assessmentis referencedto NUREG/CR-6966 and NOAA TechnicalMemorandumOAR PMEL-136(ReferenceNOAA 2007).In addition, the more recently issued NRC guidance, JLD-ISG-2012-06,also addresses tsunami assessment.However,a screeningassessmentis appliedand JLD-lSG-2A12-06         provides guidanceon detailedtsunamimodelingthat is beyondthe scopeof a screeningassessment.
TechnicalMemorandumOAR PMEL-136reflectsa similartsunamiscreeningassessment describedby NUREG/CR-6966.
The NUREG/CR-6966      screeningassessmentis based on a regionalscreeningand a site screening.The regionalscreeningconsistsof researchinghistoricalrecordsfor tsunami recordsand the potentialfor tsunami-generatingsources.The site screeningevaluatesthe distancemeasuredalong site basedon the horizontaldistancefrom a coast,the longitudinal a river,and the gradeelevationin comparisonto the effectsof a tsunami.This assessment approachis based on a reviewof historicalrecordsand databases.
NUREG/CR-6966identifiesthat tsunamisare generatedby rapid,large-scaledisturbances of a body of water. The most frequent cause of tsunamis is an earthquake; however, landslidesand volcanoescan also initiatetsunamis.Becauseof the tsunami-generation sequenceassociatedwith earthquakes,dip-slipearthquakes(dueto verticalmovement)are more efficient at generatingtsunamis than strike-slipearthquakes(due to horizontal PERRYNUCLEARPOWERPLANT                                                         Page 28 of 42

NTTF Recommendation     2.1 (HazardReevaluations):   Flooding                        Revision1 FirstEnergyCorporation                                                            March2.2016 movement).Furthermore,to generatea major tsunami,a substantialamountof slip and a largerupturearea is required.Consequently,    only largeearthquakeswith magnitudesgreater than 6.5 generateobservabletsunamis.
As part of the assessment,the NOAA naturalhazardstsunamidatabaseis used to review historicaltsunamieventsand associatedrunupsfor the east coastof the UnitedStatesand Canada.Of the totalevents,therewere 7 tsunamieventsthat produced14 runupsoccurring in the Great Lakesregionfrom 1755to 1954.The USGS hazardfault databasefindingsare reviewedfor strongearthquakesor the verticaldisplacements    necessaryto inducea tsunami.
Additionally, the USGSearthquakehazardsprogram,the NCEERdatabase,and the Natural ResourcesCanadadatabaseare reviewedfor historicalearthquakesin the region.
ODNR data is also reviewed for earthquake-generated         tsunami and landslide-induced tsunami. Lastly, the NOAA natural hazards volcano database is reviewed to assess volcanoesin the Lake Erie region.
3.6.4. Results Accordingto ODNR, an earthquake-generated        tsunami in Lake Erie would requirea very large earthquake on the order of magnitude 7 .0 or greater and significantvertical displacement.Historically,in the Lake Erie region, the largest earthquakesare in the magnitude5.0 range. Preliminaryanalysisof post-glacialsedimentsin the region has not yielded evidence of a large earthquakein the last few thousand years. Furthermore, earthquakesin the region,for which sufficientdata are available,show primarilyhorizontal ratherthan verticalmovement,which is not as conduciveto tsunamigeneration.
Tsunamiscan also be generatedby the downslopemovementof a very largevolumeof rock or sediment,eitherfrom a rockfallabovethe water or from a submarinelandslide.Although large amounts of unconsolidatedsedimentsare washed into Lake Erie each year when shorelinebluffs are undercutby wave action,these masses lack sufficientvolume and rapid collapseto displacea volumeof waterthatwouldcreatea tsunami.Lake Eriealso has a very gentlebottomprofile,particularlyin the westernand centralbasins.The easternbasin has steeper slopes, but not steep enough for a large amount of sedimentto suddenlyflow downslopein a submarinelandslide.
The NOAA naturalhazardstsunamidatabaseidentifiesonly two occurrencesof non-seiche (or non-wind-induced)  tsunami events in the Great Lakes region. The two occurrences yieldedslightor smallwave effects.
The USGS EarthquakeHazards Programfault databasecontainsno known Quaternary faults (or currentfaults) in this region becausegeologistshave not found any faults at the Earth's surface.Consequently,no potentialexists for strong earthquakesor the vertical displacementnecessaryto inducea tsunami.Variousearthquakedatabases,includingthe USGS Earthquake Hazards Program earthquake database, the National Center for EarthquakeEngineeringresearchcatalog,and NaturalResourcesCanada,identifythat the largesteventsin the vicinityare no greaterthan magnitude5.0.
Lastly,no volcanoesare locatedin the Lake Erie             accordingto the NOAA natural hazardsvolcanodatabase.
Tsunamiis not the controllingfloodeventat PNPP.
3.7. Gombined Effect Flood (including Wind-GeneratedWaves) (ReferencePNPP2015m)
Evaluationof floodscausedby precipitation    eventsis coveredin AppendixH.1 of NUREG/CR-7046.Thethreealternativesare addressedin floodingon streamsand rivers(Section3.1),which PERRYNUCLEARPOWERPLANT                                                            Page 29 of 42

NTTF Recommendation      2.1 (HazardReevaluations): Flooding                        Revision1 FirstEnergyCorporation                                                         M a r c h2 , 2 0 1 6 identifiesthe resulting water surface elevations.Combined effect flooding evaluates the componentof addedwaves inducedby 2-yearwind speedalongthe criticaldirection.
Evafuationof floodsalongthe shoresof enclosedbodiesof water is coveredin AppendixH.4.1 of NUREG/CR-7046      and includesone alternative:
Gombination of:
       -     Probablemaximumsurgeand seichewith wind-waveactivity.
       -     The lesser of the 100-yearor the maximum controlledwater level      the enclosed body of water.
Three alternativesare specifiedin Appendix H.4.2 of NUREG/CR-7046for streamside locations of enclosed bodies of water. Each of the alternativesconsideredhas three componentscontributing   to the water surfaceelevation.
Alternative 1 - Combination of:
The lesserof one-halfof the PMF or the 500-yearflood; Surge and seiche from the worst regionalhurricaneor windstormwith wind-wave activity;and The lesser of the 1O0-yearor the maximumcontrolledwater level in the enclosed body of water.
Afternatitve2 - Combination of:
PMF in the stream; A 25-yearsurgeand seichewith wind-waveactivity;and The lesserof the 1OO-year  or the maximumcontrolledwater level in the enclosed body of water.
          . Alternative3-Gombinationof:
          -    A 25-yearflood in the stream;
          -    Probablemaximumsurgeand seichewith wind-waveactivity;and
          -    The lesserof the 100-yearor the maximumcontrolledwater level in the enclosed body of water.
3.7.1. Basis of lnputs Inputsincludethe following:
          . PMSSfrom Calculation    50:47.000
          . Wave parametersfor Lake Erie at PNPPfrom Calculation50:47.000 o    10O-yearor maximumcontrolledwater levelin Lake Eriefrom Calculation50:46.000
          . Lake Erie historicalmaximumsurgefrom Calculation50:46.000
          . Lake Erie 2S-yearsurgefrom Calculation50:46.000
          . 2-yearwind speed
          . Site topography 3.7.2. Computer Software Programs
          . ArcGlSDesktop10.1 o    HEC-GeoRAS10.1
          . HEC-RAS4.1
           . MicrosoftExcel PERRYNUCLEARPOWERPLANT                                                          Page 30 of 42

NTTF Recommendation     2.1 (HazardReevaluations): Flooding                           Revision1 FirstEnergyCorporation                                                           March2,2016 3.7.3. Methodology Each combinationincludescoincidentwind-waveactivity. Coincidentwind-waveactivityis determinedfor the critical flooding combinationusing the USACE guidance outlined in USACE CoastalEngineeringManual (ReferenceUSACE 2008).Wind setup is the effect of horizontalstress on the water surface.Runup is the maximumelevationof wave uprush abovestillwaterlevel.
3.7.3.1. H.4.1Gombination Probablemaximum surge and seiche is discussedin Section 3.5. Wind wave activity includeswave height,wind setup,and wave runup.Wave heightand wlnd setupare included as part of the PMSS developed using Delft3D model. Wave runup is determinedin accordancewith USACEguidanceon the shorelineand bluffslopesadjacentto Lake Erie.
3.7,3.2. H.4.2GombinationAlternatives As a boundingapproach,the maximum Lake Erie water level from all three alternatives, includingthe initialwater level and surge effects,is used as the downstreamboundary conditionfor MajorStreamand MinorStreamflooding,and combinedwith the PMF for each stream.lt is determinedthat the maximumLake Eriewater levelhas no significanteffecton the PMF analyses.Based on the analysesand resultsfor the Major Stream and Minor Stream,the DiversionStreamwas not specifically  analyzedfor combinedeffectflooding.The DiversionStream is not adjacentto the power block. Therefore,wind wave activity has no specificconsequence.
3.7.4. Results The H.4.1Combinationmaximumwater surfaceelevationis 582.8feet Perry Local Datum, includingwind setup,and occurswest of the power block along the shorelinebluff slopes.
The maximumeffects due to wind wave activityoccur at a locationjust east of the power blockalonga sectionof shorelinewith steeperbluffslopes.Wave actionanalysisconcludes that a maximumwave runupol27 .5 feet may be generatedon the shorelinebluffslopes.The PMSSmaximumwatersurfaceelevationat this locationis 581.9 feet PerryLocalDatum.The maximumwave runup elevationduring the controllingPMSS is equal to 609.5 feet Perry LocalDatum,which is well belowthe site.
The maximumcombinedwatersurfaceelevationfor the MajorStreamand the MinorStream are the PMF results.
The Major Stream and DiversionStream are not directly adjacentto PNPP safety-related structures.Therefore,wind wave activity has no specificconsequence.The Minor Stream PMF floodingis maintainedwithinthe streambanks,eliminatingthe potentialfor wind wave effectsat the power block.
3.8. Local Intense Precipitation(ReferencePNPP 2015c,PNPP 2016a,and PNPP 2016c)
The LIP is an extremeprecipitation eventat a given location.The LIP evaluationis performed in accordancewith NUREG/CR-7046. Cool-seasonalternativesare determinedto be bounded by the all-seasonalternative.
3.8.1. Basis of Inputs
: sii:  :Hfi';#l;:n:r*r"::         ?il?rt:tix','iin.;:
PERRYNUCLEARPOWERPLANT                                                            Page 31 of 42

NTTF Recommendation     2.1 (HazardReevaluations):   Flooding                         Revision1 FirstEnergyCorporation                                                             March2,2016 o  Site underdrainsystemdrawings
               . Manning'sroughnesscoefficients o  MajorStreammaximumwater surfaceelevationresults 3.8.2. Computer Software Programs
             . ArcGlSDesktop10.1
             . FLO-2DPro, Build 14-08-09(incorporating   SWMM 5.0.022)
             . HEC-RAS4.1
             . MATLAB8.6.0.267246 o   MicrosoftExcel 2013 3.8.3. Methodology The effects of LIP are analyzedusing FLO-2D software.The softwareuses shallowwater equationsto routestormwaterthroughoutthe site. FLO-2Ddepictssite topographyusinga digitalelevationmodel(DEM)capturingall terrainfeatures,such as grading,slopes,drainage divides,and low areasof the site.
The MajorStreamis incorporatedintothe modelas a staticwater level boundarycondition.
The grid model DEM is developedfrom ground surface informationcombinedwith the maximumwatersurfaceelevationsdeterminedfor the MajorStreamas a boundarycondition.
The entire drainagearea of the Minor Stream is incorporatedinto the model domain.The MinorStreameightfoot diameterculvertdischargingto LakeErieis includedin the modeling.
The culvert feature is modeled using the SWMM software incorporatedinto the FLO-2D software.HEC-RAS software is used to derive a stage-dischargerelationshipassignedto the culvert.The DiversionStream and associatedwatersheddo not affect the area of the power blockanalyzedfor the effectsof LlP. The DiversionStreamand associatedwatershed alsodo not affectthe MajorStreamor the MinorStream.The DiversionStreamis not included in the FLO-2Dmodeling.
Manning'sroughnesscoefficientvalues are selectedbased on land cover type using the guidance provided in the FLO-2D manual. Two types of obstructionsare modeled:
buildings/structuresthat completelyblockthe water passage,and securitywall barriersthat could be overtoppedif the waterdepth increasesabovethe top of the wall.The leveefunction within FLO-2Dis used to incorporatesite securityfeatures,which could impactthe natural drainagecharacteristics   of the site.
The site storm drainagenetwork is incorporatedinto the model using the S\A/MMsoftware incorporatedinto the FLO-2D software. All inlets are modeled with a 50 percent area reductionand 25 percentperimeterreductionto accountfor inletgratingand potentialdebris accumulation.The pipe networkwas also modeledusing a 10 percentreductionof pipe capacity.In addition,securityrestrictionsaffectingpipe capacityare also incorporated.
The elementsof the roof drain systemthat connectdirectlyto the storm drainagenetworkor groundwaterare incorporatedinto the model. Roof drains that dischargedirectlyto the ground are not modeled.The roof drain system is incorporatedinto the modelingwithout reductions.Roof elevationsare modeledas describedby site drawings.Roof parapetsare modeledusingthe levee function.Roof scuppersare incorporatedinto the parapetlevees.
The site also includesan underdrainsystem that is independentof the storm drainage network.Sixteenunderdrainmanholelocationsare modeledas open inlets.Inletreductions are incorporatedfor the physicalinlet grating. However,due to the large three feet to four feet diameterunderdrainpipe sizes,no reductionof pipe capacityis included.
PERRYNUCLEARPOWERPLANT                                                             Page 32 of 42

NTTF Recommendation      2.1 (HazardReevaluations):   Flooding                        Revision1 FirstEnergyCorporation                                                            March2,2016 The site-specific rainfallis appliedas a 6-hourstormeventbasedon 5-minuteincrementsto capturethe highestintensityof the distribution.Front,one-third,center,two-thirds,and end-loading temporal distributionsare consideredin the evaluation.No rainfall losses are includedin the modeling.
3.8.4. Results The site-specificbeyonddesignbasis rainfallwith an end loadingdistributionproducesthe criticalresultsfor the effectsof LIP flooding.The maximumwater surfaceelevationsat the power block rangefrom 619.9feet Perry Local Datumto 621.3feet Perry Local Datum.ln general,the southend of the powerblockaroundthe Unit2 TurbineBuildingresultsin higher maximumwatersurfaceelevations.The resultingmaximumwatersurfaceelevationsexceed 57 door thresholdelevationsof the powerblock.The maximumwater depthsat the 57 door locationsrangefrom 0.1 feet to 1.0 feet above the door thresholdelevationsfor durations rangingfrom 0.1 hoursto 6 hours.
Maximum water surface elevations north of the power block at the Service Water PumphouseBuildingand the EmergencyServiceWater PumphouseBuildingrange from 619.3feet PerryLocalDatumto 620.5feet PerryLocalDatum.The resultingmaximumwater surface elevationsexceed one door thresholdelevationat the ServiceWater Pumphouse.
The maximumwater depth is 0.1 feet above the door thresholdelevationfor a durationof 0.1 hours.The resultingmaximumwater surfaceelevationsexceedthe two door thresholds and one louveropeningof the EmergencyServiceWater Pumphouse.The maximumwater depths range from 0.7 feet to 1.0 feet above the openingelevationsfor durationsranging from 5.8 hoursto 6 hours.
The resultingmaximumwater surface elevationsexceed two door thresholdelevationsat the Unit2 CirculatingWaterPumphouse.The maximumwaterdepthsare 0.5 feet abovethe door threshold elevationsfor durations of 0.7 hours. The Unit 2 CirculatingWater Pumphouseis an abandonedunit that does not communicate,in terms of flooding,with SSCs requiredfor safe plant operationor shutdown.Therefore,floodingof this buildingis inconsequential  to plantsafety.
4.0 COMPARISONOF BEYONDDESIGNBASISWITH UPDATEDDESIGNBASIS The reevaluatedmaximumwater surfaceelevationsdue to the LlP, storm surge (PMSS),and combinedeffectfloodfor stormsurgeincludingwind-generated      wavesexceedthe designbasis.
For LIP flooding,the designbasisand beyonddesignbasisevaluationsare identicalexceptfor the rainfallinput.The design basis rainfallinput is the CorrectedPMP front loadedtemporal distribution.The beyonddesignbasis rainfallinput is the site-specificPMP and is evaluatedfor the front,one-third,center,two-thirds,and end-loadingtemporaldistributions.
The design basis LIP analysisresultsexceed26 door thresholdelevationsof the power block and the two door thresholdsand one louver opening of the Emergency Service Water Pumphouse.Door thresholdelevationsat the Service Water PumphouseBuildingand the CirculatingWater Pumphousesare not exceeded.The beyonddesignbasis LIP resultsexceed 57 door thresholdelevationsof the power block, one door of the ServiceWater Pumphouse Building,the two door thresholdsand one louver opening of the EmergencyService Water Pumphouse,and two doors of the Unit 2 CirculatingWater Pumphouse.The design basis maximumwater surfaceelevationsat the power block rangefrom 619.8 feet Perry Local Datum to 620.7feet Perry Local Datum.The beyonddesign basis maximumwater surfaceelevationsat the power block exceedthe design basis range by 0.1 feet to 0.6 feet.
PERRYNUCLEARPOWERPLANT                                                            Page 33 of 42

NTTF Recommendation     2.1 (HazardReevaluations):    Flooding                    Revision1 FirstEnergyCorporation                                                         March2,2016 For the lakestormsurgeflooding,the designbasisassumesthe surgeacts only in one direction.
A site-specificwind and pressurefield is developedas part of the reevaluation.More recent stormsprovidethe controllingwind for reevaluatedsurgefloodingat PNPP.
As previouslyindicated,the PMSS maximumstillwatersurfaceelevationexceedsthe design basiselevationof 580.5feet Perry Local Datumby a maximumvalue of 2.3 feet. The UHS for PNPP is Lake Erie. Although the design basis is exceeded,the PMSS Stillwatersurface elevationremainsbelowthe safety-related     pumpsand equipmentlocatedaboveelevation586.5 feet Perry Local Datum in the emergencyservicewater pumphouse.Additionally,the PMSS minimumstillwatersurfaceelevationis lowerthan the designbasis of 565.26feet Perry Local Datumby 2.0 feet. However,previousevaluationdeterminedthat thereis adequatenet positive suctionhead and submergenceof the emergencyservicewater pumpsfor a resultingelevation as low as 559.0feet Perry Local Datum (ReferencePNPP 2004).
For the combinedeffect flood from storm surge includingwind-generatedwaves, the design basisincorporatedthe guidanceoutlinedby the USACEShoreProtection,Planningand Design, TechnicalReportNo. 4 (ReferenceUSACE 1966).The beyonddesign basis coincidentwind-wave activityis determinedusing the current USACE guidanceoutlinedin USACE Coastal Engineering Manual.
The maximumsurgerunupexceedsthe designbasiselevationof 607.9feet PerryLocalDatum by a maximum value of 1.6 feet. However,the maximum effects of the PMSS event are maintainedon the bluffsadjacentto LakeErie.The sitegraderemainshigherthan the maximum effectsof the PMSS event. The wave runup would cause the lake level to increaseas well as decreasethroughthe cyclingof the waves. The long intaketunnel of the plant dampensthe impactof the high and low wave action.The waterlevelswithinthe pumphousetend to equalize to the sustainedaverageheightof the lake.Therefore,the resultingbeyonddesignbasisPMSS effects are inconsequentiaI to safety-related structures.
The comparisonsof existingand reevaluatedflood hazardsare providedin Table5.
PERRYNUCLEARPOWERPLANT                                                         Page 34 of 42

NTTFRecommendation     2.1 (HazardReevaluations):    Flooding                       Revision1 FirstEnergyCorporation                                                           March2,2016 Table 5 - Comparison of Existing and ReevaluatedFlood Hazardsat PNPP Flood-Gausing Flood Hazard Reevaluation Mechanism        Design Basis             Gomparison Results Floodingin       MaiorStream(t)             Bounded       MaiorStream streamsand       (ReferencePNPP                           (Reference  PNPP2015p) rivers           2015p)                                   All-Season  PMFElevation is 628.5 PMF Elevationis                          feetPerryLocalDatum(at railline 628.5 feet Perry                          bridge).
LocalDatum(at railline bridge).
PMF Flow is                              All-SeasonPMF Flow is 34,200cfs.
34,200cfs.
Cool-season                              Cool-Seasonboundedby all-boundedby all-                           season.
season.
MinorStream(a)                            MinorStream (ReferencePNPP                            (ReferencePNPP2015b) 201sb)                                   All-SeasonPMF Elevationis 619.7 PMF Elevationis                          feet Perry Local Datum.
619.7feet Perry LocalDatum.
P M F F l o wi s 1 , 1 0 0               All-SeasonPMF Flowis 1,100cfs.
cfs.
Cool-season                               Cool-Seasonboundedby all-boundedby all-                           season.
season.
DiversionStream(a)                        DiversionStream (ReferencePNPP                            (ReferencePNPP2015b) 2015b)                                    PMF Elevationis 629.2feet Perry PMF Elevationis                           LocalDatum.
629.2 feet Perry LocalDatum.
PMF Flowis 4,200                          PMF Flowis 4,200cfs.
cfs.
Cool-season                               Cool-seasonboundedby all-boundedby all-                            season.
season.
PERRYNUCLEARPOWERPLANT                                                           Page 35 of 42

NTTF Recommendation   2,1 (HazardReevaluations):Flooding                             Revision1 FirstEnergyCorporation                                                            March2,2016 Table 5 - Gomparisonof Existing and ReevaluatedFlood Hazardsat PNPP (Continued)
Flood-Causing Flood Hazard Reevaluation Mechanism    Design Basis          Comparison Results Dam breaches    No upstream           Bounded         Dam assessmentindicatesno and failures    impoundments.                        watersheddams.
Stormsurge      Watersurface          Notbounded. Watersurfaceelevationis 582.8 elevation  is 580.5 Exceedscurrent feetPerryLocalDatum(Reference feetPerryLocal        designbasis. P N P P2 0 1 5 h ) .
Datum(USAR, Section   2.4.5.2.2).
Lowwater                              Lowwaterelevationis 563.2feet elevation  is 565.26                  PerryLocalDatum(Reference feetPerryLocal                        PNPP201sh).
Datum(USAR, Section   2.4.11.6).
Seiche          Thisflood-causing Bounded             Boundedby storm surge (Reference mechanismis not                       PNPP20159).
described specificallyfor the site in the USAR (USAR,Section 2.4.6).
Tsunami         This flood-causing Bounded            Tsunamiassessment         indicates a mechanismis                           slightpossibility   of tsunamis in the identlfiedas not                      GreatLakesregion.However,the applicablein the                      seismicity in the regionsuggestsno USAR (USAR,                           potentialexistsfor strong Section2.4.6).                        earthquakes   or the vertical displacement    necessary   to inducea substantial tsunami(Reference PNPP2015i).
lce-induced     This flood-causing Bounded            lce-inducedfloodingis boundedby flooding        mechanismis                           the all-seasonPMF event identifiedas not                      (ReferencePNPP 2015e).
plausiblein the USAR (USAR, Section2.4.7).
Channel         This flood-causing Bounded            Channeldiversionis not migrationor     mechanismis                           characteristicfor adjacentstreams diversion       identifiedas not                      (ReferencePNPP2015e).
applicablein the USAR (USAR, Section2.4.$.
PERRYNUCLEARPOWERPLANT                                                            Page 36 of 42

NTTF Recommendation       2.1 (HazardReevaluations):  Flooding                          Revision1 FirstEnergyCorporation                                                             M a r c h2 , 2 0 1 6 Table 5 - Comparison of Existing and ReevaluatedFlood Hazardsat PNPP (Continued)
Flood-Gausing                                             Ffood Hazard Reevaluation Mechanism        Design Basis         Comparison        Results Combinedeffect      Wave runupon         Notbounded.       Waverunupon LakeErieshoreline flood(including     LakeErieshoreline Exceedscurrent       bluffsis 609.5feet PerryLocal wind-generated      bluffsis 607.9       designbasis.      Datum(Reference    PNPP2015h).
waves)              PerryLocal Datum (USAR,Section 2.4.2.2).                              Windwaveeffectson streamsare notapplicable.
                     \Mnd wave effects on streamsare not applicable.
LIP                 Maximumwater         Notbounded. Maximumwater surfaceelevations surfaceelevations Exceedscurrent at the powerblock rangefrom 619.9 at the powerblock designbasis.         feet PerryLocal Datumto 621.3feet rangefrom 619.8                        Perry Local Datum.(c) feet Perry Local                       (ReferencePNPP 2016c)
Datumto 620.7 feet Perry Local pq{urn.(axo)
(ReferencePNPP 2016b)
(a)Valuesare basedon the reconstituteddesignbasisvaluesdiscussedin Section2.3.
(b)Thedoorschedulefor the designbasisLIPfloodhazardresultsare providedin Attachment   1.
(c)Thedoorschedulefor the beyonddesignbasisLIPfloodhazardresultsare providedin Attachment       2.
5.0 INTERIMAND PLANNEDFUTUREACTIONS The FfoodingHazardReevaluationReportevaluatedthe applicablefloodinghazardsfor PNPP.
Three of the postulatedreevaluatedflood hazardevents (lake flooding,combinedeffects,and LIP) resultedin maximumflood water elevationshigherthan previouslycalculatedfor PNPP.
These postulatedflooding events are consideredbeyond design basis events and do not constitutean operabilityconcern.The PMSS event and the combinedeffectsfor wave runupon the Lake Erie shorelineresultsare inconsequential. Therefore,no interimor futureactionsare plannedfor this event.
The interimactionplan is to continuewith actionsassociatedwith ConditionReportCR 2015-08036 until all design basis modificationsbased on Calculation50:64.000LIP results are complete.Design basis modificationswill be implementedfor the storm sewer system,the underdrainsystem,and door specificprotectionor analysis.lmplementation   of the modifications for the storm sewer system and the underdrainsystem,as incorporatedinto the design basis LIP Calculation50:64.000,are requiredfor the beyonddesignbasis LIP Calculation50:66.000 to be valid.Door protectionwill be developedfor the beyonddesignbasisCalculation50:66.000 LIP resultsthrougheither analysisor physicalbarriers.Analysiswill determinethe volumeof inflowthroughthe doors for the durationof flooding.The inflowvolume will be comparedto internalfloodinganalysesto determineif externalfloodingis boundedor not. Physicalbarriers will be determinedas eitherpermanentbarriersor throughprocedure.
PERRYNUCLEARPOWERPLANT                                                             Page37 ot 42

NTTF Recommendation  2.1 (HazardReevaluations):Flooding                        Revision1 FirstEnergyCorporation                                                     March2.2016 6.0 ACRONYMS ANS                AmericanNuclearSociety ANSI               AmericanNationalStandardsInstitute ArcMap             Arc Map Software ArcGlS             Arc GeographicInformationSystemSoftware AutoCAD            AutomatedComputerAided DesignSoftware CFR               Code of FederalRegulations cfs               CubicFeet per Second CR                ConditionReport Delft3D           Delft3-Dimensional Software Delft3D-FLOW      Flow Moduleof Deft3DSoftware Delft3D-WAVE      Wave Moduleof Deft3DSoftware Delft3D-RGFGRID Grid GenerationModuleof Delft3DSoftware Delft3D-QUICKIN Modification/generation Moduleof Delft3DSoftware DEM               DigitalElevationModel DTM               DigitalTerrainModel ECP               Engineering ChangePackage ESP               EarlySite Permits FENOC             FirstEnergyNuclearOperatingCompany FLO.2D            FLO 2-Dimensional  Software GIS               GeographicInformationSystem HEC-GeoRAS        HydrologicEngineeringCenter GeographicRiver Analysis System software HEC.HMS           HydrologicEngineeringCenterHydraulicModelingSystemsoftware HEC.RAS           HydrologicEngineeringCenterRiverAnalysisSystemsoftware IGLD85                        Great LakesDatumof 1985 International JLD.ISG           Japan Lessons-LearnedProjectDirectorateInterimStaff Guidance LIP               LocalIntensePrecipitation MATLAB            MatrixLaboratorySoftware NAVD 88           NorthAmericanVerticalDatumof 1988 NCEER             NationalCenterfor EarthquakeEngineeringResearch NGVD 29.          NationalGeodeticVerticalDatumof 1929 NID               Nationallnventoryof Dams NOAA              NationalOceanicand AtmosphericAdministration NRC               NuclearRegulatoryCommission PERRYNUCLEARPOWERPLANT                                                      Page 38 of 42

NTTF Recommendation   2.1 (HazardReevaluations):Flooding                      Revision1 FirstEnergyCorporation                                                    March2,2016 NRCS                NationalResourcesConservationService NTTF                NearTerm Task Force NUREG               US NuclearRegulatoryCommissionRegulation NUREG/CR            US NuclearRegulatoryCommissionRegulationContractorsReport NWS                 NationalWeatherService OAR PMEL            Oceanic and AtmosphericResearch Pacific Marine Environmental Laboratory ODNR                Ohio Departmentof NaturalResources PFA                 PromptFunctionalityAssessment PMF                 ProbableMaximumFlood PMP                 ProbableMaximumPrecipitation PMS                 ProbableMaximumStorm PMSS                ProbableMaximumStormSurge PMWS                ProbableMaximumWindstorm PNPP                PerryNuclearPowerStation RG                  RegulatoryGuide SSCs                Structure,Systems,and Components SWMM                Storm Water ManagementModel software UHS                 UltimateHeatSink USACE               U.S.Army Corpsof Engineers USAR                UpdatedSafetyAnalysisReport USBR                U.S. Bureauof Reclamation USGS                U.S. GeologicalSurvey 7.0 REFERENGES (ANSI N170-1976) American National Standard, Standardsfor Determining Design Basrs Flooding at Power Reactor Sifes, Prepared by the American Nuclear Society Standards CommitteeWorkingGroupANS-2.8,1976.
(ANSI/ANS-2.8-1992)ANS, American NationalStandardfor DeterminingDesign Basis Flooding at Power Reactor Sifes, Prepared by the American Nuclear Society Standards Committee WorkingGroupANS-2.8,1992.
(JLD-ISG-2013-01) NRC, Guidancefor Assessmentof FloodingHazardsdue to Dam Failure, Revision0, July 2013.
(JLD-ISG-2012-06) NRC,Guidancefor Performinga Tsunami,Surgeor SeicheFloodingHazard Assessment,Revision0, January2013.
(NEl August 2012) NEl, Report 12-08,Overviewof ExternalFloodingReevaluations, August 2012.
PERRYNUCLEARPOWERPLANT                                                    Page 39 of 42

NTTF Recommendation     2.1 (HazardReevaluations):  Ffooding                           Revision1 FirstEnergyCorporation                                                            March2,2016 (NOAA 1956)U.S. WeatherBureau,U.S. Departmentof Commerce,SeasonalVariationof the Probable Maximum Precipitation East of the 105thMeridian for Areas from 10 to 1000 Square Miles and Durationsof 6, 12, 24, and 48 Hours, HydrometeorologicalReportNo. 33, Silver Spring Maryland,1956.
(NOAA1978)NationalWeatherService,NationalOceanicand AtmosphericAdministration,             U.S.
Departmentof Commerce,ProbableMaximumPrecipitationEstimafes,United SfafesEasf of the 105thMeridian,HydrometeorologicalReportNo. 51,SilverSpring Maryland,1978.
(NOAA 1982)NationalWeatherService,NationalOceanicand AtmosphericAdministration,            U.S.
Department of Commerce, Application of Probable Maximum Precipitation Estimates,United Sfafes Easf of the 105thMeridian, HydrometeorologicalReport No. 52, Silver Spring Maryland, 1982.
(NOAA 2OO7)NationalOceanicand AtmosphericAdministration,         TechnicalMemorandumOAR PMEL-136,Scientificand Technical/ssues in TsunamiHazard Assessmentof Nuclear Power Plants,May 2007.
(NRC March2012)NRC, LettertoLicensees,RequestforInformationPursuanttoTitle 10 of the Codeof FederalRegulations    50.54(f)RegardingRecommendations     2.1,2.3, and 9.3 of the Near-Term Task ForceReviewof Insightsfrom the FukushimaDai-ichiAccident,March 12,2012.
(NRC May 2012) NRC, Letterto Licensees,Prioritizationof ResponseDue Dates for Request for InformationPursuantto Title 10 of the Code of Federal Regulations50.54(f)Regarding FloodingHazardReevaluations      for Recommendation  2.1 of the Near-TermTask ForceReview of lnsightsfrom the FukushimaDai-ichiAccident,May 11, 2012.
(NUREG-0800)NRC, NUREG-0800,StandardReview PIan for the Review of Safety Analysis Repods for Nuclear Power Plants: LWR Edition - Stfe Characterisfibs and Site Parameters (Chapter2), ML070400364,March2007.
(NUREG/CR-7046)NRC, NUREGICR-7046,PNNL-20091, Design-BasisFlood Estimationfor Site Characterizationat Nuclear Power Plantsin the United Sfafes of America, ML113214195, November2011.
(NUREG/CR-6966)NRC, NUREG/CR-6966,TsunamiHazard Assessmentat Nuclear Power Plant Sdesin the UnitedSfafesof America,NationalTechnicalInformationService,March2009.
(ODNR 2006) Ohio Departmentof NaturalResources,Divisionof GeologicSurvey, Surficial Geologyof the Cleveland North30 X 60 Minute Quadrangle,March 2006.
(ODNR 2013) Ohio Departmentof Natural Resources,ProbableMaximumPrecipitationStudy for the Sfafe of Ohio, preparedby AppliedWeatherAssociates,LLC, February2013.
(PNPP2004)FENOCCalculationP45-081, Evaluationof Net PositiveSuctionHead (NPSH)and SubmergenceRequiremenfsfor the Emergency ServiceWater (ESW Sysfem Pumps, Revision 0.
(PNPP 2015a)FENOC Calculation50:32.000,PNPP StreamModificationPMP, Revision0.
(PNPP2015b)FENOCCalculation50:33.000,PNPP StreamModificationPMF, Revision0.
(PNPP2015c)FENOCCalculation50:36.000,PNPPSife-SpecificAll-SeasonPMP, Revision0.
(PNPP2015d)FENOCCalculation50:43.000,PNPP DamsAssessmenf,Revision0.
(PNPP2015e)FENOCCalculation50:44.000,PNPPlce Jam and ChannelMigration Assessmenf,Revision0.
(PNPP2015f)FENOCCalculation50:45.000,PNPPWind Climatology,Revision0.
PERRYNUCLEARPOWERPLANT                                                             Page40 of 42

NTTF Recommendation    2.1 (HazardReevaluations):  Flooding                      Revision1 FirstEnergyCorporation                                                        March2,2016 (PNPP20159)FENOCCalculation50:46.000,PNPPSurgeand SeicheScreening,Revision0.
(PNPP2015h)FENOCCalculation50:47.000,PNPPSu4geand SeicheAnalysis,Revision0.
(PNPP2015i)FENOCCalculation        50:48.000,PNPPTsunamiAssessment,   Revision0.
(PNPP2015j)FENOCCalculation50:52.000,PNPPRainfallRunoff GISAnalysis,Revision0.
(PNPP2015k)FENOCCalculation50:53.000,PNPPSurgeand SeicheG/S Analysis,Revision 0.
(PNPP20151)FENOCCalculation50:54.000,PNPPSu4geand SeicheCalibration,Revision0.
(PNPP2015m)FENOCCalculation         50:55.000,PNPPCombinedEvents,Revision0.
(PNPP2015n)FENOCCalculation50:58.000,PNPPStreamModification         BermFailureAnalysis, Revision0.
(PNPP 2015o) FENOC Calculation50:59.000, PNPP Site-SpecificAII-SeasonSub-Hour Probable Maximum PrecipitationAnalysisfor 1-10 Square Miles, Revision0.
(PNPP 2015p) FENOC Calculation50:62.000, PNPP Major Stream Rail ModificationPMF, Revision0.
(PNPP 2015q) FENOC Calculation50:63.000, PNPP Major StreamAccess Road Modification Probable Maximum Flood, Revision0.
(PNPP2016a)FENOCCalculation50:31.000,PNPP GISAnalysisforEffecfsof L/P, Revision0 (PNPP2016b)FENOCCalculation50:64.000,PNPP SiteModificationsLocallntense Precipitation,Revision0.
(PNPP 2016c) FENOC Calculation50:66.000, PNPP Site ModificationsBeyond Design Basis Local lntensePrecipitation,Revision0.
(PNPP CN-1.1)CN-1.1 Posf Foundations,Sife Roads, and Catch             Revision0, Postlt NoteP-01.
(PNPPCN-1.1.1)CN-1.1.1 StormDrainage/ Catch BasinSysfem,                 Post lt Note P-01.
(PNPP CR 2015-05079)Condition Report 2015-05079,External Flooding during a Probable Maximum Flooding Event (West Srde of Plant).
(PNPP ECP 13-0802)EngineeringChange Package 13-0802,Minor Stream Modification, Revision0.
(PNPP CR 2015-08036)ConditionReporl2015-08036,PFA neededfor sitefloodingr'ssues.
(USACE 1966) U.S. Army Corps of Engineers,Coastal EngineeringResearchCenter, Shore Protection,Planningand Design,TechnicalReportNo. 4, Washington,D.C., 1966.
(USACE2008) U.S. Army Corps of Engineers,CoastalEngineeringManual,EM 1110-2-1100, August2008.
(USAR)PerryNuclearPowerPlant,UpdatedSafetyAnalysisReport,Revision17.
(USBR 1973) U.S. Departmentof the Interior,U.S. Bureau of Reclamation,Design of Small Dams,A Water ResourcesTechnicalPublication,SecondEdition,1973.
(USGS1943)U.S.Department      of the Interior,           Survey,PerryQuadrangle, U.S.Geological Perry,Ohio1905,Reprinted    1943.
PERRYNUCLEARPOWERPLANT                                                        Page41 of 42

NTTF Recommendation   2.1 (HazardReevaluations):Flooding                       Revision1 FirstEnergyCorporation                                                     March2,2016 (USGS 1992)U.S. Departmentof the Interior,U.S.GeologicalSurvey,Perry Quadrangle,Ohio-Lake Co., 7.S-MinuteSen'es,Perry,Ohio 1960, Revised1992.
(USGS 1994)U.S. Departmentof the Interior,U.S. GeologicalSurvey,Perry Quadrangle,Ohio-Lake Co., 7.S-MinuteSen'es,Perry,Ohio 1994.
(USGS2010)U.S. Departmentof the Interior,U.S.GeologicalSurvey,Perry Quadrangle,Ohio, 7.S-MinufeSen'es,Perry,OH 2010.
PERRYNUCLEARPOWERPLANT                                                      Page 42 of 42

NTTFRecommendation   2.1 (HazardReevaluations):
Flooding                Revision1 FirstEnergyCorporation                                                  2.zArc March ATTACHMENT       1 Updated Design Basis LIP Flood Hazard Results Front Temporal Distribution (ReferencePNPP2016b)
PERRYNUCLEARPOWERPLANT                                               Page 1 of 8

NTTF Recommendation        2.1 (HazardReevaluations):Flooding                                Revision1 FirstEnergyCorporation                                                                  March2.2416 Updated Design Basis LIP Flood Hazard Results at Door Locations for Front LIP Temporal Distribution MaxFlow Depth Above                               Margin:A=
Ground                              Dooi Eliv -
Building                             Door Elev. Elevation         iltllaxWSE         Max,WSE,'
Door       Grid
                                                                          .., ft POI ID                                              ft PNPP                              ft.PNPP Number                          Number     Number    Datum        ft     uAvoaa          ,Ditum '      (ft) 1     U1Auxiliary Building 1AX 406       74326   620.504      0.13     619.29          620.22       0.3 2      U1Auxiliary Building 1AX404        74642   620.465      0.03     619.39          620.32       0.1 3      U1Auxiliary Building 1AX403        75274   620.456      0.58     619.29          620.22       0.2 4      U1Auxiliary Building 1M 407        68496   620.614      0.41     619.48          620.41       0.2 5      U1Auxiliary Building 1AX 405       68499   620.506      0.09     619.53          620.46       0.0 6       U1 TurbineBuilding    1TB307      59754   620.500      0.10     619.53          620.46       0.0 7       U1 TurbineBuilding    1TB308      58385   620.500      0.03     619.21          620.14       0.4 8       U1 TurbineBuilding    1TB306      61482   624.500      0.27     618.87          619.80       4. 7 9       U1 TurbineBuilding    1 T B3 1 6  71777   620.392      0.03     619.35          620.28       0.1 10        U1 HeaterBay        1 H B3 0 6  64199   620.410      0.03     619.16          620.09       0.3 11        U1 HeaterBay        1 H B3 1 0  68856   620.385      0.03     619.29          620.22       0.2 12        Ul HeaterBay        1 H B3 1 4  67868   620.870      0.05     619.74          620.67       o.2 13        U1 HeaterBay        1H8311      67870   620.416      0.05     619.36          620.29       0.1 14        Ul HeaterBay        1HB309      70808   620.610      0.03     619.46          620.39       0.2 15        U1 HeaterBay        1 H B3 0 8  71778   620.261      0.12     619.25          620.18       0.1 U1 TurbinePower 16          Complex           1TP306      73051   620.420      0.20     619.34          620.27       0.2 U1 TurbinePower 17          Complex           1TP303      67841   620.516      0.03     619.53          620.46       0.1 18      U1 Off Gas Building   10G303      63836   620.467      0.11     619.43          620.36       0.1 19      Ul Off Gas BuiHing    10G302      63499   620.431      0.08     619.43          620.36       0.1 20      U1 Off Gas Building   10G 304     61123   620.467      0.05     619.54          620.47       0.0 U1WaterTreatment 21           Building         0\ /T 101   55241   620.401      0.21     619.26          620.19       0.2 WaterTreatment 22           Building         owT103      55936   620.399      0.30     619.43          620.36       0.0 WaterTreatment 23           Building         owT102      58372    620.429     0.48     619.43          620.36       0.1 DieselGenerator 24           Building         oDG106      64479   620.512      0.18     619.63          620.56       0.0 PERRYNUCLEARPOWERPLANT                                                                     Page 2 o f 8

NTTF Recommendation         2.1 (HazardReevaluations).Flooding                                 Revision1 FirstEnergyCorporation                                                                      March2,2016 Updated Design Basis LIP Flood Hazard Results at Door Locations for Front LIP Temporal Distribution MaxFlow Depth .                                ',...'...:.
Above                               MarginA =,
                                                               , Ground.                             ?oor Elev -
                                                               'Elevation                            , MaxWE Building
                                 'Door Door Elev.                      .Max'WSE Grid                          ,, flt,.
POI ID                                              ft PNPP                                ft P.NPP Number                          Number      Number   Datum         ft     NAVD88 , DatOm,:               (ft)
DieselGenerator 25         Building           oDG105       u146   620.547       0.05    619.62            620.55       0.0 DieselGenerator 26         Building           oDG104       63813  620.680       0.03    619.78            620.71       0.0 DieselGenerator 27         Bu i l d i n g     oDG103       63478  620.650       0.03    619.75            620.68       0.0 DieselGenerator 28         Building           oDG102       63143  620.503       0.03    619.59            620.52       0.0 DieselGenerator 29         Building           o D G1 0 1   62808  620.487       0.03     619.52           620.45       0.0 30     RadwasteBuilding       oRW422       62470  620.459       0.11     619.52           620.45       0.0 31     RadwasteBuilding       oRW407       62132  620.393       0.14    619.50            620.43       0.0 32     RadwasteBuilding       oRW411       61457  620.435       0.10     619.44           620.37       0.1 33     RadwasteBuilding       oRW101       62819  620.473       0.40     619.43           620.36       0.1 Intermediate 34         Building            0 l B3 1 5  76859  620.594       0.59     619.31           620.24       0.3 Intermediate 35         Bu i l d i n g      0 l B3 1 6  78439  620.570       0.36     619.49           620.42       0.1 Intermediate 36         Building            o t B3 1 7  78120  620.416       0.33     619.53           620.46       0.0 37      ServiceBuilding       o s B1 1 3   71398  620.430       0.54     619.58           620.51       -0.1 38      ServiceBuilding       o s B1 1 4   71721  620.434       0.40    619.57            620.50       -0.1 39      ServiceBuilding       osB107       70749  620.466       0.58    619.59            620.52       -0.1 40      ServiceBuilding       osB104       70098  620.436       0.55    619.60            620.53       -0.1 41      ServiceBuilding       osB105       68131  620.493       0.57    619.64            620.57       -0.1 42      ServiceBuilding       osB108       66808  620.477       0.52    619.66            620.59       -0.1 43      ServiceBuilding       osB103       60476  620.482       0.51    619.68            620.61       -0.1 44      ServiceBuilding       osB102       &+810  620.461       0.51    619.66            620.59       -0.1 45      ServiceBuilding       osB101       64477  620.467       0.29     619.62           620.55       -0.1 46    U2Auxiliary   Building 2AX 403       78748  620.419       0.41     619.68           620.61       -0.2 47    U2Auxiliary   Building 24d,404       78745  620.415       0.28     619.71           620.64       -0.2 48    U2Auxiliary   Building  2AX 406      79062  620.439       0.31     619.73           620.66       -0.2 PERRYNUCLEARPOWERPLANT                                                                        Page o f 8

NTTF Recommendation        2.1 (HazardReevaluations): Flooding                        Revision1 FirstEnergyCorporation                                                            March2,2016 Updated Design Basis LIP Flood Hazard Results at Door Locations for Front LIP Temporal Distribution MaxFlow Depth Above                       MarginA:='
:Ground                      Door Elev -
                                                                                            'Max WSE Building                              Door Elev. Elevation     MaxWSE Door      Grid POI ID                                              ft PNPP                      ft PNPP Number                         Number    Number      Datum         ft    Nefosa   Datum        '{ft}',:
49    U2Auxiliary Building 2AX405       73000     620.546      0.30    619.55   620.48        0.1 50    U2Auxiliary Building zpx 407      72041     620.469      0.47    619.57   620.50        0.0 51     U2TurbineBuilding      2TB-E     77146     620.499      0.34    619.77   620.70        -0.2 52     U2TurbineBuilding      2TB-D     77780     620.426      0.43    619.77   620.70        -0.3 53     U2 TurbineBuilding    2TB316     80003     620.440      0.63    619.80   620.73        -0.3 54     U2TurbineBuilding      2rB-C     80320     620.311      0.70    619.80   620.73        -0.4 55     U2TurbineBuilding     2TB306     70722     624.500      0.43    619.71   620.64        3.9 56     U2TurbineBuilding      2TB-B     66782     620.373      0.63    619.70   620.63        -0.3 57     U2TurbineBuilding     2TB308     67445     620.318      0.53    619.70   620.63        -0.3 58     U2TurbineBuilding      2TB-A     65462     620.325      0.54    619.76   620.69        -0.4 59     U2TurbineBuilding     2TB 307    66130     620.311      0.49    619.75   620.68        -0.4 60       U2 HeaterBay        2HB303     78716     620.476      0.65    619.81   620.74        -0.3 61       U2 HeaterBay        2HB306     74889     620.430      0.88    619.75   620.68        -0.2 U2TurbinePower 62         Complex           2TP303     72999     620.377      0.28    619.55   620.48        -0.1 63     U2 Off Gas Building   20G 304    66467     620.461      0.59    619.74   620.67        -0.2 64     U2 Off Gas Building   20G 302    68454     620.422      0.47    619.59   620.52        -0.1 65     U2 Off Gas Building   20G 303    68782     620.477      0.48    619.60   620.53        -0.1 66    ServiceWater Pump      SW102      58081     620.000      0.15    618.55   619.48        0.5 67    ServiceWater Pump       SW105     6 11 8 3  620.000      0.29    618.75   619.68        0.3 68    ServiceWater Pump      sw 103     57039     620.000      0.08    618.17   619.10        0.9 69    ServiceWater Pump      SW 104     56698     620.000      0.28    618.42   619.35        0.6 70    ServiceWater Pump      SW 101     6 11 9 0  620.000      0.54    618.80   619.73        0.3 Emergency  Water 71            Pump            EW 202    65576     619.500      0.44    618.90   619.83        -0.3 Emergency  Water 72            Pump            EW201     64916     619.500      0.54    619.09   620.O2        -0.5 Emergency  Water 73            Pump           EW East    66916     619.500      0.65    619.10   620.03        -0.5 Circulating Water 74            Pump          u2 cw 101 96539       621.500       0.39   620.59    621.52        0.0 PERRYNUCLEARPOWERPLANT

NTTF Recommendation       2.1 (HazardReevaluations):Flooding                         Revision1 FirstEnergyCorporation                                                           March2,2016 Updated Design Basis LIP Flood Hazard Results at Door Locations for Front LIP Temporal Distribution MaxFlow Depth Above'                       MarginA =
Ground                       Door,EIev,-
Building                            Door Elev. Elevation       MaxWSE        :MaxWSE Door      Grid POI ID                                            ft PNPP                 ft     ft PNPP Number                        Number    Number     Datum        ft     NAVD88     Daturn.      (ft)
CirculatingWater 75          Pu mp          u2 cw 102   96901    621.500      0.80     620.60    621.53       0.0 CirculatingWater 76          Pump           u2 cw 103 97636      626.500      0.07     620.92    621.85       4.7 CirculatingWater 77          Pump           u2 cw 104   95463    626.500      0.03     624.38    625.31       1.2 CirculatingWater      U2 CW 78          Pump             South     97994    624.500      0.40     620.61    621.54       3.0 CirculatingWater 79          Pump           u1 cw 101 83930      621.500      0.13     619.95    620.88       0.6 CirculatingWater 80          Pump           u1 cw 102 83929      621.500      0.03     619.95    620.88       0.6 CirculatingWater 81          Pump           u1 cw 103 85532      626.500      0.03     620.85    621.78       4.7 CirculatingWater 82          Pump           u1 cw 104 84900      626.500      0.03     624.55    625.48       1.0 CirculatingWater      U1 CW 83          Pump             South     84887    624.500      0.27     620.22    621.15       3.3 PERRYNUCLEARPOWERPLANT                                                              Page 5 of 8

NTTF Recommendation          2.1 (HazardReevaluations):       Flooding                       Revision1 FirstEnergyCorporation                                                                    March2,2016 Updated Design Basis LIP Flood Hazard Results Flood Duration above Door Elevationfor Front Temporal Distribution POI ID                                                                 MaximumWaterSurface Number          Building                    Door     Flooding Duration       Etevation Number           Hours          ft PNPPDatum 1       U1Auxiliary     Building        1AX 406     Door Not Flooded         620.2 2       U1Auxiliary     Building        1AX 404     Door Not Flooded         620.3 3       U1Auxiliary     Building        1AX403      Door Not Flooded         620.2 4       U1Auxiliary     Building        1AX 407     Door Not Flooded         620.4 5       U1Auxiliary     Building        1AX 405     Door Not Flooded         620.5 6       U1 TurbineBuilding              1TB307      Door Not Flooded         620.5 7       U1 TurbineBuilding              1TB308      Door Not Flooded         620.1 I       U1 TurbineBuilding              1TB306      Door Not Flooded         619.8 I       U 1 T u rb i n eB u i l d i n g 1 T B3 1 6  Door Not Flooded         620.3 10         Ul HeaterBay                 1HB306      Door Not Flooded         620.1 11         Ul HeaterBay                 1 H B3 1 0  Door Not Flooded         620.2 12         Ul HeaterBay                 1 H B3 1 4  Door Not Flooded         620.7 13         Ul HeaterBay                 1 H B3 1 1  Door Not Flooded         620.3 14         Ul HeaterBay                 1HB 309     Door Not Flooded         620.4 15         Ul HeaterBay                 1 H B3 0 8  Door Not Flooded         620.2 U1TurbinePower 16            Complex                   1TP306      Door Not Flooded         620.3 U1 TurbinePower 17            Complex                   1TP303      Door Not Flooded         620.5 18      U1 Off Gas Building             10G 303     Door Not Flooded         620.4 19      U1 Off Gas Building             10G302      Door Not Flooded         620.4 20      U1 Off Gas Building             10G 304     Door Not Flooded         620.5 U1 WaterTreatment 21             Building                 owT101      Door Not Flooded         620.2 U1 WaterTreatment 22             Building                 owT103      Door Not Flooded         620.4 U1 WaterTreatment 23             Building                 owT102      Door Not Flooded         620.4 DieselGenerator 24             Building                 oDG106      Door Not Flooded         620.6 Diesel Generator 25             Building                 oDG105      Door Not Flooded         620.6 DieselGenerator 26             Building                 oDG104      Door Not Flooded         620.7 DieselGenerator 27             Building                 oDG103      Door Not Flooded         620.7 PERRYNUCLEARPOWERPLANT                                                                      Page 6 of 8

NTTF Recommendation      2.1 (HazardReevaluations): Flooding                         Revision1 FirstEnergyCorporation                                                          M a r c h2 . 2 0 1 6 Updated Design Basis LIP Flood Hazard Results Flood Duration above Door Elevation for Front Temporal Distribution POI ID                                                       Maxim,umWaterSurface Number         Building           Door     Flooding Duration       Elevation Number           Hourc          ft PNPPDatum DieselGenerator 28            Building       oDG102       Door Not Flooded         620.5 DieselGenerator 29            Building       o D G1 0 1   Door Not Flooded         620.5 30       RadwasteBuilding    oRW422       Door Not Flooded         620.5 31       RadwasteBuilding    oRW407       Door Not Flooded         620.4 32       RadwasteBuilding    oRW411       Door Not Flooded         620.4 33       RadwasteBuilding    oRW 101      Door Not Flooded         620.4 34     IntermediateBuilding   o t B3 1 5  Door Not Flooded         620.2 35      IntermediateBuilding  o t B3 1 6  Door Not Flooded         620.4 36      IntermediateBuilding  0 l B3 1 7  Door Not Flooded         620.5 37        ServiceBuilding    o s B1 1 3         0.7                620.5 38        ServiceBuilding    o s B1 1 4         0.6                620,5 39        ServiceBuilding    osB107             0.3                620.5 40        ServiceBuilding    osB104             0.8                620.5 41        ServiceBuilding    osB105             0.5                620.6 42        ServiceBuilding    osB108             0.9                620.6 43        ServiceBuilding    osB103             1.0                620.6 44        ServiceBuilding    osB102             1.0                620.6 45        ServiceBuilding    OSB1 0 1           0.6                620.6 46      U2AuxiliaryBuilding  2AX 403            1.6                620.6 47      U2AuxiliaryBuilding  2M 404             2.3                620.6 48      U2AuxiliaryBuilding  2AX 406            3.1                620.7 49      U2AuxiliaryBuilding  2AX405       Door Not Flooded         620.5 50      U2AuxiliaryBuilding  zFX 407      Door Not Flooded         620.5 51       U2TurbineBuilding     2TB-E            2.1                620.7 6.2(usemaximum 52       U2TurbineBuilding     2TB-D         of 6 hrs)             620.7 53       U2TurbineBuilding   2TB316             1.8                620.7 54       U2 TurbineBuilding    2TB-C            3.8                620.7 55       U2TurbineBuilding   2TB306       Door Not Flooded         620.6 6.8(usemaximum 56       U2 TurbineBuilding    2TB-B         of 6 hrs)             620.6 9.7(usemaximum 57       U2 TurbineBuilding   2TB308         of 6 hrs)             620.6 PERRYNUCLEARPOWERPLANT                                                             Page 7 of 8

NTTF Recommendation      2.1 (HazardReevaluations):
Flooding                        Revision1 FirstEnergyCorporation                                                         March2,2016 Updated Design Basis LIP Flood HazardResults Flood Duration above Door Elevationfor Front Temporal Distribution POI ID                                                     MaximurnWaterSurface Number         Building           Door   Flooding Duration        Elevation Number         Hours          ft PNPPDatum 58      U2TurbineBuilding      2TB-A           4.0                620.7 59      U2 TurbineBuilding    2TB 307          3.5                620.7 60        U2 HeaterBay        2HB303           1.7                620.7 61        U2 HeaterBay        2HB306           5.8                620.7 U2TurbinePower 62           Complex          2TP303           1.3               620.5 63      U2 Olf Gas Building   20G 304          1.5                620.7 64      U2OffGasBuilding      20G 302          0.9                620.5 65      U2OffGasBuilding      20G 303          0.3                620.5 66      ServiceWater Pump     SW 102    Door Not Flooded         619.5 67      ServiceWater Pump      SW105    Door Not Flooded          619.7 68      ServiceWater Pump     SW 103    Door Not Flooded          619.1 69      ServiceWater Pump     SW 104    Door Not Flooded          619.4 70      ServiceWater Pump     SW 101    Door Not Flooded          619.7 Emergency  Water              6.1(usemaximum 71             Pump           EW 202        of 6 hrs)            619.8 Emergency  Water              10.0(usemaximum 72             Pump           EW 201        of 6 hrs)             620.0 Emergency  Water              7.3(usemaximum 73             Pump           EW East       of 6 hrs)             620.0 74    CirculatingWaterPump   u2 cw 101  Door Not Flooded          621.5 75    CirculatingWaterPump   u2 cw 102  Door Not Flooded          621.5 76    CirculatingWater Pump  u2 cw 103  Door Not Flooded          621.8 77    CirculatingWaterPump   u2 cw 104  Door Not Flooded          625.3 U2 CW 78    CirculatingWaterPump     South    Door Not Flooded          621.5 79    CirculatingWaterPump   ul cw 101  Door Not Flooded          620.9 80    CirculatingWaterPump   u1 cw 102  Door Not Flooded          620.9 81    CirculatingWaterPump   u1 cw 103  Door Not Flooded          621.8 82    CirculatingWater Pump  u1 cw 104  Door Not Flooded          625.5 U1 CW 83    CirculatingWaterPump     South    Door Not Flooded          621.2 PERRYNUCLEARPOWERPLANT                                                           Page 8

NTTF Recommendation  2.1 (HazardReevaluations):
Flooding                 Revision1 FirstEnergyCorporation                                             March2.2016 ATTACHMENT      2 Beyond Design Basis LIP Flood Hazard Results End TemporalDistribution (ReferencePNPP2016c)
PERRYNUCLEARPOWERPLANT                                               Page 1 of 8

NTTF Recommendation       2.1 (HazardReevaluations):    Flooding                                    Revision1 FirstEnergyCorporation                                                                       March2.2016 Beyond Design Basis LIP Flood Hazard Results at Door Locations for Elnod Lil- l empora lDistribution LIP Ten Max Flow Depth Above                                   MarginA.=
Ground ,                                DoorElev-Building                              Door Elev. rElevation      MaxWSE                      Max WSE'
                                                                                   '.'..'.'....,'.        r t - .
Door       Grid POI ID                                               ft PNPP                                ft'PNPP Number                          Number     Number     Datum            ft     ;A$            .....t,,-
                                                                                            ,Datum                (ft) 1     U1Auxiliary Building 1AX 406       74326     620.504         0.51     619.67        620.60               -0.1 2      Ul AuxiliaryBuilding 1AX 404       74642     620.465         0.33     619.69        620.62               -0.2 3      U1Auxiliary Building 1AX403        75274     620.456         1.02     619.73        620.66               -0.2 4      Ul AuxiliaryBuilding 1A.X,407      68496     620.614         0.69     619.76        620.69               -0.1 5      U1Auxiliary Building 1AX405        68499     620.506         0.32     619.76        620.69               -0.2 6       U1TurbineBuilding     1TB307      59754     620.500         0.31     619.74        620.67               -0.2 7       U1 TurbineBuilding    1TB308      58385     620.500         0.08     619.26        620.19               0.3 8       U1 TurbineBuilding    1TB306      61482     624.500         0.38     618.98        619.91               4. 6 I       U1 TurbineBuilding    1 T B3 1 6  71777     620.392         0.30     619.62        620.55               -o.2 10        U1 HeaterBay        1HB306      64199     620.410         0.05     619.18        620.11                0.3 11        Ul HeaterBay        1 H B3 1 0  68856     620.385         0.26     619.52        620.45               -0.1 12        U1 HeaterBay        1 H B3 1 4  67868     620.870         0.10     619.79        620.72                0.2 13        U1 HeaterBay        1H8311      67870     620.416         0.14     619.45        620.38                0.0 14        U1 HeaterBay        1HB309      70808     620.610         0.15     619.58        620.51                0.1 15        U1 HeaterBay        1 H B3 0 8  71778     620.261         0.49     619.62        620.55               -0.3 U1TurbinePower 16          Complex           1TP306      73051     620.420         0.52     619.66        620.59               -0.2 U1TurbinePower 17           Complex          1TP303      67841     620.516         0.26     619.76        620.69               -0.2 18      Ul Off Gas Building   10G303      63836     620.467         0.37     619.69        620.62               -0.2 19      U1 Off Gas Building   10G302      63499     620.431         0.34     619.69        620.62               -0.2 20      Ul Off Gas Building   10G 304     61123     620.467         0.24     619.73        620.66               -0.2 U1 WaterTreatment 21           Building         owT101      55241     620.401         0.45     619.50        620.43                0.0 WaterTreatment 22           Building         owT103      55936     620.399         0.58     619.71        620.64               -0.2 WaterTreatment 23           Building         owT102      58372     620.429         0.79     619.74        620.67               -0.2 PERRYNUCLEARPOWERPLANT                                                                             Page 2 of 8

NTTF Recommendation       2.1 (HazardReevaluations).      Flooding                            Revision1 FirstEnergyCorporation                                                                     March2,2016 Beyond Design Basis LIP Flood Hazard Results at Door Locations   s for End LIP Ten emDora I Distribution Max Flow Depth Above              ..          MarginA,=
Ground                         Door Elev-Building                                   Door Elev. Elevation       M"xwie''         MaxWSE Door        Grid POIID                                                   ft PNPP                           ft PNPP Number                         Number      Number        Datum         ft      nr$oaa      Datum       ,,,{ft)
DieselGenerator 24         Building          oDG106       6/,479      620.512       0.44      619.89     620.82       -0.3 DieselGenerator 25         Bu i l d i n g    oDG105       64146       620.547       0.31      619.88     620.81       -0.3 DieselGenerator 26         Bu i l d i n g    oDG104       63813       620.680       0.11      619.86     620.79      -0.10 DieselGenerator 27         Building          oDG103       63478       620.650       0.13      619.85     620.78       -0.1 DieselGenerator 28         Building          oDG102       63143       620.503       0.27      619.83     620.76       -0.3 DieselGenerator 29         Building          o D G1 0 1   62808       620.487       0.30      619.79     620.72       -0.2 30     RadwasteBuilding      oRW422       62470       620.459       0.39      619.80     620.73       -0.3 31     RadwasteBuilding      oRW407       62132       620.393       0.44      619.80     620.73       -0.3 32     RadwasteBuilding      oRW411       61457       620.435       0.40      619.74     620.67       -0.2 33     RadwasteBuilding      oRW101       62819       620.473       0.66      619.69     620.62       -0.1 Intermediate 34         Building           o t B3 1 5  76859       620.594       1.07      619.79     620.72       -0.1 Intermediate 35         Bu i l d i n g     o t B3 1 6  78439       620.570       0.84      619.97     620.90       -0.3 Intermediate 36         Building           o t B3 1 7  78120       620.416       0.79      619.99     620.92       -0.5 37      ServiceBuilding      o s B1 1 3   71398       620.430       0.91      619.95     620.88       -0.4 38      ServiceBuilding      o s B1 1 4   71721       620.434       0.78      619.95     620.88       -0.4 39      ServiceBuilding      osB107       70749       620.466       0.95      619.96     620.89       -0.4 40      ServiceBuilding      osB104       70098       620.436       0.92      619.97     620.90       -0.5 41      ServiceBuilding      osB105       68131       620.493       0.93      620.00     620.93       -0.4 42      ServiceBuilding      osB108       66808       620.477       0.89      620.03     620.96       -0.5 43      ServiceBuilding      osB103       66476       620.482       0.86      620.03     620.96       -0.5 44      ServiceBuilding      osB102       64810       620.461       0.83      619.98     620.91       -0.5 45      ServiceBuilding      osB101       64r'.77     620.467       0.58      619.91     620.84       -0.4 PERRYNUCLEARPOWERPLANT                                                                       Page 3 of 8

NTTF Recommendation       2.1 (HazardReevaluations):     Flooding                                 Revision1 FirstEnergyCorporation                                                                        March2,2016 Beyond Design Basis LIP Flood Hazard Results at Doorr Locations   for End LIP Temporal ns Tor             em        Distribution Max Flow Depth ,
Above                                MargihA:=
Ground                               Door'El6i ,.-
Building                                 Door Elev. Elevation            Max WSE          ,MaxWSE Door      Grid                                 : , f t , , . ft PNPP POI ID                                                 ft PNPP Number                         Number    Number         Datum         ft      NAVD88 Daturn                 (ft) 46    U2Auxiliary Building 2AX403       78748        620.419      0.78       620.05          620.98      -0.6 47    U2Auxiliary Building zPY\404      78745        620.415      0.65       620.08          621.01      -0.6 48    U2Auxiliary Building 2AX 406      79062        620.439      0.67       620.09          621.02      -0.6 49    U2Auxiliary Building   24X.405    73000        620.546      0.69       619.94          620.87      -0.3 50    U2Auxiliary Building zPJ\407      72041        620.469      0.85       619.95          620.88       -0.4 51     U2 TurbineBuilding     2TB.E     77146        620.499      0.71       620.14          621.07      -0.6 52     U2 TurbineBuilding     2TB-D     77780        620.426      0.80       620.14          621.07      -0.6 53     U2TurbineBuilding     2TB316     80003        620.440      1.20       620.37          621.30      -0.9 54     U2TurbineBuilding      2TB-C     80320        620.311      1.30       620.40          621.33      -1.0 55     U2TurbineBuilding     2TB306     70722        624.500      0.90       620.18          621.11       3.4 56     U2TurbineBuilding      2TB.B     66782        620.373      1.09       620.16          621.09       -0.7 57     U2TurbineBuilding     2TB308     67445        620.318      0.99       620.16          621.09      -0.8 58     U2 TurbineBuilding     2TB-A     65462        620.325      0.89       620.11          621.04       -0.7 59     U2 TurbineBuilding    2TB 307    66130        620.311      0.84       620.10          621.03       -0.7 60       U2 HeaterBay        2HB303     78716        620.476       1.25      620.41          621.34      -0.9 61       U2 HeaterBay        2HB306     74889        620.430      1.38       620.25          621.18       -0.7 U2TurbinePower 62         Complex           2TP303     72999        620.377      0.67       619.94          620.87      -0.5 63     U2 OffGasBuilding 20G 304        66467        620.461      0.93       620.08          621.01      -0.6 64     U2 Off Gas Building   20G 302    68/.54       620.422      0.89       620.01          620.94      -0.5 65     U2 Off Gas Building   20G 303    68782        620.477      0.89       620.01          620.94       -0.5 66    ServiceWater Pump       SW 102    58081        620.000      0.27       618.67          619.60       0.4 67    ServiceWater Pump       SW105     6 11 8 3     620.000      o.57       619.03          619.96       0.0 68    ServiceWater Pump       SW 103    57039        620.000      0.27       618.36          619.29       0.7 69    ServiceWater Pump       SW 104    56698        620.000      0.47       618.61          619.54       0.5 70    ServiceWater Pump       SW 101    61190        620.000      0.87       619.13          620.06       -0.1 Emergency  Water 71            Pump            EW202     65576        619.500      0.84       619.30          620.23       -0.7 PERRYNUCLEARPOWERPLANT                                                                           Page 4 of 8

NTTF Recommendation     2.1 (HazardReevaluations):     Flooding                            Revision1 FirstEnergyCorporation                                                                M a r c h2 , 2 0 1 6 Beyond Design Basis LIP Flood Hazard Results at Door Lco ccations for End LIP Ten empora I Distribution Max Flow Depth Above ,                          MarginA =
Giouhd                           Door Etev-Building                               Door Elev. Elevation       MaxWSE            :,MaxUtlS! '
Door        Grid                             ' ft, POI ID                                              ft PNPP                         ,ft PNP-P Number                       Number      Number       Datum          ft     NAVD88 Datum                 {ft}
EmergencyWater 72          Pump            EW 201      64916      619.500        1.00     619.55    620.48             1.0 EmergencyWater 73          Pump           EWEast       66916      619.500        1.10     619.55    620.48             1.0 CirculatingWater 74          Pump          u2 cw 101 96539          621.500        a.82     621.02    621.95           -0.5 CirculatingWater 75          Pump          u2 cw 102     96901      621.500        1.23     621.03    621.96           -0.5 CirculatingWater 76          Pu mp         u2 cw 103 97636          626.500        0.28     621.13    622.06            4.4 CirculatingWater 77          Pump          u2 cw 104     95463      626.500        0.08     624.43    625.36            1.1 CirculatingWater     U2 CW 78          Pump             South      97994      624.500        0.84     621.05    621.98            2.5 CirculatingWater 79          Pump          u 1c w 1 0 1 83930       621.500        0.20     620.02    620.95            0.6 CirculatingWater 80          Pump          u1 cw 102 83929          621.500        0.06     619.98    620.91            0.6 CirculatingWater 81          Pump          u1 cw 103 85532          626.500        0.22     621.04    621.97            4. 5 CirculatingWater 82          Pump          u1 cw 104 84900          626.500        0.03     624.55    625.48            1.0 CirculatingWater     U1 CW 83          Pump             South      84887      624.500        0.45     620.40    621.33            3.2 PERRYNUCLEARPOWERPLANT                                                                   Page 5 of 8

NTTF Recommendation              2.1 (HazardReevaluations): Flooding                       Revision1 FirstEnergyCorporation                                                                 March2,2016 Beyond Design Basis LIP Flood Hazard Results Flood Duration above Door Elevationfor End Temporal Distribution POI ID                                                                          MaximumWater Number                Building                    Door       Flooding rDuration Suface Elevation Number             Hours         ft PNPPDatum 1   U1Auxiliary      Building               1AX 406             0.30              620.6 2    U1Auxiliary      Building               1pJ<404             0.40              620.6 3    U1Auxiliary      Building               1AX403              0.40              620.7 4    U1Auxiliary      Building               1AX 407             0.10              620.7 5    U1Auxiliary      Building               1AX 405             0.20              620.7 6    U1 TurbineBuilding                      1TB307              0.40              620.7 7    U 1 T u rb i n eB u i l d i n g         1TB308        Door Not Flooded        620.2 8    U l T u rb i n eB u i l d i n g         1TB306        Door Not Flooded        619.9 9    U1 TurbineBuilding                      1 T B3 1 6          0.40              620.6 10   U1 HeaterBay                            1HB306        Door Not Flooded        620.1 11   U1 HeaterBay                            1 H B3 1 0          0.20              620.5 12   U1 HeaterBay                            1 H B3 1 4    Door Not Flooded        620.7 13   Ul HeaterBay                            1 H B3 1 1    Door Not Flooded        620.4 14   Ul HeaterBay                            1 H B3 0 9    Door Not Flooded        620.5 15   Ul HeaterBay                            1 H B3 0 8          0.50              620.6 16   U1 TurbinePowerComplex                  1TP306              0.40              620.6 17   U1 TurbinePowerComplex                  1TP303              0.20              620.7 18   U1 Off Gas Building                     10G 303             0.20              620.6 19   U1 Off Gas Building                     10G302              0.30              620.6 20   U1 Off Gas Building                     10G 304             0.90              620.7 21   U1 WaterTreatmentBuilding               OWT1 0 1      Door Not Flooded        620.4 22   U1WaterTreatment               Building owT103              0.50              620.6 23   U1WaterTreatment               Building owT102              0.50              620.7 24   DieselGeneratorBuilding                 oDG106              0.80              620.8 25   DieselGeneratorBuilding                 oDG105              0.60              620.8 26   DieselGeneratorBuilding                 oDG104              0.40              620.8 27   DieselGeneratorBuilding                 oDG103              0.50              620.8 28   DieselGeneratorBuilding                 oDG102              0.70              620.8 29   DieselGeneratorBuilding                 o D G1 0 1          0.40              620.7 30   RadwasteBuilding                        oRW422              0.60              620.7 31   RadwasteBuilding                        oRW407              0.70              620.7 32   RadwasteBuilding                        oRW411              0.50              620.7 PERRYNUCLEARPOWERPLANT                                                                   Page 6 of 8

NTTF Recommendation     2.1 (HazardReevaluations):
Flooding                          Revision1 FirstEnergyCorporation                                                         March2.2016 Beyond Design Basis LIP Flood Hazard Results Flood Duration above Door Elevationfor End Temporal Distribution POI ID                                                                 MaximumWater Number           Building              Door        Flooding Duration    SurfaceElevation Number              Hours           ft PNPPDatum 33   RadwasteBuilding            oRW 101               0.20                620.6 34   IntermediateBuilding         0rB315               0.30                620.7 35   IntermediateBuilding         o t B3 1 6           0.50                620.9 36   IntermediateBuilding         o t B3 1 7           0.80                620.9 37   ServiceBuilding              o s B1 1 3           0.80                620.9 38   ServiceBuilding              o s B1 1 4           0.80                620.9 39   ServiceBuilding              osB107               0.80                620.9 40   ServiceBuilding              osB104               0.90                620.9 41   ServiceBuilding              osB105               0.80                620.9 42   ServiceBuilding              osB108               0.90                621.0 43   ServiceBuilding              osB103               0.90                621.0 44   ServiceBuilding              osB102               1.00                620.9 45   ServiceBuilding              osB101               0.80                620.8 46   U2AuxiliaryBuilding          2AX 403              1.20                621.0 47   U2AuxiliaryBuilding          zPX,404              1.60                621.0 48   U2AuxiliaryBuilding          2AX406               1.90                621.0 49   U2AuxiliaryBuilding          2AX 405              0.40                620.9 50   U2AuxiliaryBuilding          zAX 407              0.60                620.9 51   U2TurbineBuilding             2TB-E               1.60                621.1 6.10(use maximum  of 6 52   U2TurbineBuilding             2TB-D              hour)                621.1 53   U2TurbineBuilding            2TB316               1.30                621.3 54   U2TurbineBuilding             2TB-C               1.70                621.3 55   U2TurbineBuilding            2TB 306        Door Not Flooded          621.1 56   U2TurbineBuilding             2TB.B               4.40                621.1 6.50(usemaximum   of 6 57   U2TurbineBuilding            2TB308              hour)                621.1 58   U2TurbineBuilding             2TB-A               1.90                621.0 59   U2 TurbineBuilding           2TB 307              1.80                621.0 60   U2 HeaterBay                 2HB303               1.30                621.3 61   U2 HeaterBay                 2HB306               2.70                621.2 62   U2 TurbinePowerComplex       2TP303               1.00                620.9 63   U2 Off Gas Building          20G 304              1.20                621.0 64   U2 Off Gas Building          20G 302              0.90                620.9 PERRYNUCLEARPOWERPLANT                                                           Page 7 of 8

NTTF Recommendation      2.1 (HazardReevaluations):
Flooding                          Revision1 FirstEnergyCorporation                                                         March2.2016 Beyond Design Basis LIP Flood Hazard Results Flood Duration above Door Elevationfor End Temporal Distribution POI ID                                                                  MaximumWater Number            Building              Door       Flooding Duration    SurfaceElevation Number             Hours           ft PNPPDatum 65   U2 Off Gas Building           20G 303             0.80                620.9 66   ServiceWater Pump             SW 102        Door Not Flooded          619.6 67   ServiceWater Pump              SW105        Door Not Flooded          620.0 68   ServiceWater Pump             SW 103        Door Not Flooded          619.3 69   ServiceWater Pump             SW 104        Door Not Flooded          619.5 70   ServiceWater Pump             SW 101              0.10                620.1 71   Emergency  WaterPump          EW 202              5.80                620.2 7.50(usemaximum   of 6 72   Emergency  WaterPump          EW 201             hour)                620.5 7.10(usemaximum   of 6 73   Emergency  WaterPump          EW East            hour)                620.5 74   CirculatingWaterPump         u2 cw 101            0.70                622.0 75   CirculatingWaterPump         u2 cw 102            0.70                622.0 76   CirculatingWaterPump         u2 cw 103      Door Not Flooded          622.1 77   CirculatingWaterPump         u2 cw 104      Door Not Flooded          625.4 78   CirculatingWater Pump       U2 CW South     Door Not Flooded          622.0 79   CirculatingWaterPump         u1 cw 101      Door Not Flooded          620.9 80   CirculatingWaterPump         u1 cw 102      Door Not Flooded          620.9 81   CirculatingWaterPump         u1 cw 103      Door Not Flooded          622.0 82   CirculatingWater Pump        u1 cw 104      Door Not Flooded          625.5 83   CirculatingWaterPump        U1 CW South     Door Not Flooded          621.3 PERRYNUCLEARPOWERPLANT                                                           Page I of 8

PerryNuclearPowerPlant FENOC FlEt E sAt l,6gleat Oryatiry" P.O.Box97 10 CenterRoad Perry,Ohio44081 Frank R. Payne                                                                                             440-280-7300 GeneralPlantManager,Nuclear March24,2016 L-16-091                                                                   10cFR50.54(0 ATTN: Document           ControlDesk U.S.NuclearRegulatory          Commission 11555Rockville         Pike Rockville,      MD20852

==SUBJECT:==

PerryNuclearPowerPlant DocketNo.50-440,LicenseNo.NPF-58 Revisionof FloodHazardReevaluation             Reportin Response     to NRCRequestfor Information      Pursuant   to 10 CFR50.54(flReqardinq       the FloodinqAspectsof Recommendation          2.1of the Near-Term    TaskForce     (NTTF)  Reviewof Insiqhtsfromthe Fukushima        Dai-ichiAccident   ffAC  No. MF6099)
On March12,2012,the NuclearRegulatory                Commission   (NRC)issueda lettertitled, "Requestfor Information         Pursuantto Title 10 of the Codeof FederalRegulations 50.54(f)       Regarding  Recommendations     2.1,2.3,and9.3,of the Near-Term     TaskForce Reviewof Insights        fromthe Fukushima     Dai-ichiAccident"  [Agencywide  Documents Accessand Management              System(ADAMS)AccessionNo.ML120534340],            to all power reactorlicenseesand holdersof construction            permitsin activeor deferredstatus.
Enclosure       2 of the 10 CFR50.54(f)letteraddressesNTTFRecommendation             2.1 for ffooding.Oneof the requiredresponses              is for licenseesto submitaHazard Reevaluation       Report  (HRR)   in accordance   withthe NRC'sprioritization plan. By letter datedMay11,2012(ADAMSAccessionNo.M112097A509),                        the NRCplacedthe Perry NuclearPowerPlant(PNPP)in Category3 requiring                 a responseby March12,2015.
ThefloodHRRfor PNPPwas submittedby letterdatedMarch10,2015(ADAMS AccessionNo.ML15069A056).
By letterdatedDecember11,2015,FirstEnergy                 NuclearOperating Company(FENOC) informedthe NRCstaffof a plannedrevisionto the PNPPfloodHRRto reflectthe impactof recentplantand modelingchanges,including                majorphysicalmodifications   to the streamsandwatersheds            at the site. FENOCherebysubmitsRevision1 of the PNPPfloodHRR,whichhasbeenrevisedto reflectthesesitemodifications.

Perry Nuclear Power Plant L-16-091 Page 2 There are no regulatory commitments contained in this letter. If there are any questions or if additional information is required, please contact Mr. Thomas A. Lentz, Manager -
Fleet Licensing, at 330-315-6810.
I declare under penalty of perjury that the foregoing is true and correct. Executed on March Zf , 2016.

==Enclosure:==

Flood Hazard Reevaluation Report, Revision 1 cc:     Director, Office of Nuclear Reactor Regulation (NRR)
NRC Region Ill Administrator NRC Resident Inspector NRR Project Manager

Enclosure L-16-091 Report,Revision1 FfoodHazardReevaluation (59pagesfollow)

FLOODHAZARDREEVALUATION             REPORT rN RESPONSE  TO THEso.s4(flINFORIJlATTON       RESUESTREGARDING NEAR-TERM   TASKFORCERECOMMENDATION            2.1: FLOODING for the PERRYNUCLEARPOWERPLATTIT 10 CenterRoad North Perry,OH 44081 FlrstEnergyCorporatbn 76 Soufi Main $heet Akron, OH 44308 Revision1 March2, 2016 PdnH Nam                         Slonatue Preparsr:                     KurtRob[or            ENERCON Verifien                      Sur4 Balan           ffir                     sblaau Verifier:                     Ftuddy Dahmasfi       ENERCON itili-tt,t Approwr:                      n"t s"crimo           EI.IERCON LeadReeponsibhEngineers:
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NTTF Recommendation                2.1 (HazardReevaluations):       Flooding                            Revision1 FirstEnergyCorporation                                                                               March2,2016 Table of Contents 1.0 PURPOSE           ....                                                                                    .......4 1 . 1 . B a c k g r o u n. d                                                                               ........4 1.2. Requested             Actions...                                                                     .........4 1.3. RequestedInformation                                                                                    ......5 2.0 slTE TNFORMATTON                                                                                        .........6 2 . 1 . C u r r e nD  t e s i g nB a s i s                                                                .........8 2.1.1.       LocalIntensePrecipitation             (LlP) .                                               .......8 2.1.2.       Floodingin Streamsand Rivers                                                                 ......8 2.1.3.      Dam Breachesand Failures                                                                      .....8 2.1.4.      StormSurgeand Seiche...                                                                     .......8 2.1.5. Tsunami......                                                                                   .........8 2 . 1 . 6 . l c e - l n d u c eFdl o o d i n g                                                        .........8 2.1.7. ChannelMigration                    or Diversion                                                 .......8 2.1.8.      CombinedEffectFlood(including                \Mnd-Generated     Waves)                        .....9 2 . 1 . 9 . L o wW a t e r                                                                          ...........9 2.2.       Flood-Related        Changesto the LicenseBasis                                                    .....9 2.3.       Changesto the Watershedand LocalArea since Licenselssuance                                        ......9 2.3.1.      ProbableMaximumPrecipitation                (ReferencePNPP 2015aand PNPP2016b).........10 2.3.2.      LocalIntensePrecipitation             (LlP)(ReferencePNPP 2016aand PNPP2016b) ........10 2.3.3.      Floodingin Streamsand Rivers                                                                 ....11 2.3.3.1.        MajorStream(Reference             PNPP2015c,PNPP2015p,and PNPP2015q)........11 2.3.3.2.        MinorStream(ReferencePNPP2015aand PNPP 2015b).                                         ...12 2.3.3.3.        DiversionStream(ReferencePNPP 2015aand PNPP2015b).                                     ...13 2.4.       CurrentLicensingBasisFloodProtection                and PertinentFloodMitigationFeatures..........14 3.0 

==SUMMARY==
OF FLOODHATARDREEVALUATION                                                                       .......14 3.1. Floodingin Streamsand Rivers(ReferencePNPP 2015a,PNPP 2015b, PNPP 2015c, P N P P2 0 1 5 j P  , N P P2 0 1 5 n ,P N P P2 0 1 5 o ,P N P P2 0 1 5 p a
                                                                           , n d P N P P2 0 1 5 q ).       ........15 3 . 1 . 1 . B a s i so f I n p u t s. .: .                                                             ......16 3.1.2.      ComputerSoftwarePrograms                                                                  .......17 3 . 1. 3 . Methodology.                                                                                .....17 3 . 1. 4 . Results                                                                                   .......20 3.2.       Dam Assessment(ReferencePNPP2015d)                                                              ......21 3 . 2 . 1 . B a s i so f I n p u t s . . . .                                                            .....21 3.2.2.      ComputerSoftwarePrograms                                                                  .......21 3.2.3. Methodology                                                                                      .....22 3.2.4. Results                                                                                        .......22 PERRYNUCLEARPOWERPLANT                                                                                Page 1 of 42

NTTF Recommendation                2.1 (HazardReevaluations):       Flooding                   Revision1 FirstEnergyCorporation                                                                     March2,2016 3.3.      lce-lnduced      Flooding(Reference          PNPP2015e)                               .......22 3.3.1. Basisoflnputs....                                                                       .....22 3.3.2.         ComputerSoftwarePrograms                                                      .......22 3.3.3.         Methodology.                                                                    .....22 3.3.4.         Results                                                                       .......22 3.4.ChannelMigrationorDiversion(ReferencePNPP2015e).
3 . 4 . 1 . B a s i so f I n p u t s . . . .                                                  ......24 3.4.2.         ComputerSoftwarePrograms                                                      .......24 3.4.3.         Methodology                                                                    ......24 3.4.4.         Results                                                                       .......24 3.5. Storm Surge (ReferencePNPP 2015f, PNPP 20159, PNPP 2015h, PNPP 2015k, and P N P P2 0 1 5 r )                                                                                  ...24 3 . 5 . 1 . B a s i so f I n p u t s . . . .                                                   .....25 3.5.2.         ComputerSoftwarePrograms                                                      .......25 3.5.3.         Methodology.                                                                    .....25 3.5.4.         Results                                                                       .......27 3.6.      TsunamiAssessment(ReferencePNPP2015i)                                                .,......28 3 . 6 . 1 . B a s i so f I n p u t s . . . .                                                  ......28 3.6.2.         ComputerSoftwarePrograms                                                      .......28 3.6.3.         Methodology                                                                    ......28 3.6.4.         Results                                                                       .......29 3.7.      CombinedEffectFlood(including\Mnd-Generated                 Waves)(ReferencePNPP 2015m)..29 3 . 7 . 1 . B a s i so f I n p u t s . . . .                                                  ......30 3.7.2.         ComputerSoftwarePrograms                                                      .......30 3.7.3.         Methodology.                                                                    .....31 3 . 7 . 3 . 1 . H . 4 . 1C o m b i n a t i o. n                                        .........31 3.7.3.2.        H.4.2Combination            Alternatives.                             ..........31 3.7.4. Results                                                                               .......31 3.8.       Local IntensePrecipitation            (ReferencePNPP 2015c,PNPP 2016a,and PNPP 2016c)...31 3 . 8 . 1 . B a s i so f I n p u t s . . . .                                                  ......31 3.8.2.         ComputerSoftwarePrograms                                                      .......32 3.8.3.         Methodology                                                                    ......32 3.8.4. Results                                                                               .......33 4.0 COMPARISONOF BEYONDDESIGNBASISWITH UPDATEDDESIGNBASIS                                             ....33 5 . 0 I N T E R I MA N D P L A N N E DF U T U R EA C T I O N S                                    ........37 6.0 ACRONYMS                                                                                        ......38 7.OREFERENCES                                                                                    .........39 PERRYNUCLEARPOWERPLANT                                                                      Page 2 of 42

NTTF Recommendation  2.1 (HazardReevaluations).
Flooding                    Revision1 FirstEnergyCorporation                                               March2.2016 ATTACHMENT   1 - UpdatedDesignBasisLIP FloodHazardResultsDoorSchedule..........8 Pages ATTACHMENT2 - BeyondDesignBasisLIP FloodHazardResultsDoorSchedule.... 8 Pages PERRYNUCLEARPOWERPLANT                                                Page 3 of 42

NTTF Recommendation     2.1 (HazardReevaluations):     Flooding                        Revision1 FirstEnergyCorporation                                                             March2.2016 1.0 PURPOSE 1.1.Background In responseto the nuclearfuel damageat the FukushimaDai-ichipowerplantdue to the March 11, 2011 earthquake and subsequent tsunami, the United States Nuclear Regulatory Commission(NRC) establishedthe Near Term Task Force (NTTF) to conducta systematic review of NRC processesand regulations,and to make recommendations          to the NRC for its policydirection.The NTTF reporteda set of recommendationsthat were intendedto clarifyand strengthenthe regulatoryframeworkfor protectionagainstnaturalphenomena.
On March 12,2012 the NRC issuedan informationrequestpursuantto Title 10 of the Code of FederalRegulations,Section50.54(f) (10 CFR 50.54(f)or 50.54(f)letter)whichincludedsix (6) enclosures:
: 1. NTTF Recommendation       2.1: Seismic
: 2. NTTF Recommendation       2.1: Flooding
: 3. NTTF Recommendation       2.3: Seismic
: 4. NTTF Recommendation       2.3: Flooding
: 5. NTTF Recommendation       9.3: EP
: 6. Licenseesand Holdersof ConstructionPermits In Enclosure2 of the NRC-issuedinformationrequest(ReferenceNRC March 2012),the NRC requested that licensees reevaluatethe flooding hazards at their sites against present-day regulatoryguidanceand methodologiesbeing used for early site permits(ESP) and combined operatinglicensereviews.
On behalf of FirstEnergyNuclearOperatingCompany(FENOC)for the Perry NuclearPower Station (PNPP), this Flood Hazard ReevaluationReport (Report) providesthe information requested in the March 12, 2012 50.54(f) letter; specifically,the informationlisted under the "RequestedInformation"sectionof Enclosure2, paragraph1 ('a' through'e'). The "Requested fnformation"sectionof Enclosure2,paragraph2 ('a'through'd'), IntegratedAssessmentReport, or other additionalfuture assessmentsas necess?r'y,will be addressedseparatelyif the current designbasisfloodsdo not boundthe reevaluatedhazardfor all flood-causingmechanisms.
1.2. RequestedActions Per Enclosure2 of the NRC-issuedinformationrequest,50.54(f)letter,FENOCis requestedto performa reevaluation of all appropriateexternalfloodingsourcesfor PNPP,includingthe effects from localintense  precipitation (LlP)on the site,the probablemaximumflood (PMF)on streams and rivers, lake floodingfrom storm surges, seiches, and tsunamis,and dam failures.lt is requestedthat the reevaluation  applypresent-dayregulatoryguidanceand methodologies     being used for ESPs, combinedoperatinglicensereviews,and calculationreviewsincludingcurrent techniques,software,and methodsusedin present-day        standardengineeringpracticeto develop the flood hazard The requestedinformationwill be gatheredin Phase 1 of the NRC staffs two-phase process to implement Recommendation2.1, and will be used to identify potential "vulnerabilities" (see definitionbelow).
PERRYNUCLEARPOWERPLANT                                                               Page 4 of 42

NTTF Recommendation      2.1 (HazardReevaluations):     Flooding                              Revision1 FirstEnergyCorporation                                                                    March2.2016 The NRC prioritizationof responsesletter (ReferenceNRC May 2012) identifiesPNPP as a Category3 site. Licenseesin this categoryare expectedto reportthe resultsof the reevaluation withinthreeyearsof the March 12, 2012 50.54(f)letterissuance.
For the sites where the reevaluatedflood exceedsthe design basis,addresseesare requested to submit an interimaction plan documentingplannedactions or measuresimplementedto addressthe reevaluatedhazards.
Subsequently,addresseesshall performan integratedassessment,or other additionalfuture assessmentsas necessary,of the plant to fully identifyvulnerabilitiesand detail actions to addressthem.The scope of the integratedassessmentreportwill rncludefull poweroperations and otherplantconfigurations      that could be susceptibledue to the statusof the flood protection features.The scope also includesthose featuresof the ultimateheat sink (UHS)that could be adverselyaffectedby flood conditions(the loss of UHS from non-floodassociatedcauses is not included).lt is also requestedthat the integratedassessmentaddressthe entiredurationof the flood conditions.
A definition of vulnerabilityin the context of Enclosure 2 is as follows: Plant-specificvulnerabilities are those features important to safety that when subject to an increaseddemand due to the newly calculated hazard evaluation have not been shown to be capable of performing their intended functions.
1.3. RequestedInformation Per Enclosure2 of the NRC-issuedinformationrequest50.54(f)letter,the Reportshouldprovide documentedresults,as well as pertinentPNPP informationand detailedanalysis,and include the following:
: 1. Site informationrelatedto the flood hazard. Relevantstructure,systems,and components (SSCs)importantto safetyand the UHS are includedin the scopeof this reevaluation,             and pertinentdata concerningthese SSCs should be included.Other relevantsite data include the following:
: 1. Detailedsite information      (bothdesignedand as-built),includingpresent-day          site layout,elevationof pertinentSSCsimportant        to safety,sitetopography,  andpertinent spatialandtemporaldatasets;
: 2. Currentdesignbasisfloodelevations        for allflood-causing   mechanisms;
: 3. Flood-relatedchanges to the licensing basis and any flood protection changes (includingmitigation)   sincelicenseissuance; 4 . Changesto the watershedand localarea sincelicenseissuance; 5 . Currentlicensingbasis flood protectionand pertinentflood mitigationfeaturesat the site;and
: 6. Additionalsite details,as necessary,to assessthe floodhazard(e.g.,bathymetryand walkdownresults).
: 2. Evaluationof the flood hazard for each flood-causingmechanism,based on present-day methodologiesand regulatory guidance. Provide an analysis of each flood-causing mechanismthat may impactthe site,includingLIP and site drainage,floodingin streamsand rivers,dam breachesand failures,storm surge and seiche,tsunamis,channelmigrationor diversion,and combinedeffects.Mechanismsthat are not applicableat the site may be PERRYNUCLEARPOWERPI.ANT                                                                     Page 5 of 42

NTTF Recommendation      2.1 (HazardReevaluations): Flooding                          Revision1 FirstEnergyCorporation                                                            March2,2016 screened out; however, a justificationshould be provided. A basis for inputs and assumptions,   methodologies  and modelsused, includinginput and output files, and other pertinentdata shouldbe provided.
3 . Comparisonof currentand reevaluatedflood-causingmechanismsat the site. Providean assessmentof the currentdesignbasisfloodelevationto the reevaluatedfloodelevationfor each flood-causingmechanism.Includehow the findingsfrom Enclosure2 of the 50.54(D letter(i.e., Recommendation  2.1, flood hazardreevaluations)  supportthis determination.lf the current design basis flood bounds the reevaluatedhazard for all flood-causing mechanisms,    includehow this findingwas determined.
4 . Interimevaluationand actions taken or plannedto address any higher flooding hazards relativeto the designbasis,priorto the completionof the integratedassessmentor any future assessments.
: 5. Additionalactions beyond requestedinformationitem 1.d taken or planned to address floodinghazards,if any.
2.0 SITE INFORMATION PNPP is locatedin LakeCounty,Ohio,approximately       sevenmiles northeastof Painesville.The southernplantsite boundaryline is 3,100feet from the shorelineof Lake Erie on the west side of the site and 8,000 feet on the east side (USAR,Section2.4.1.1).Lake Erie is the major hydrologicfeatureof the location.In the vicinityof the site,the coastalwatershedis drainedby severalsmall streams(USAR,Section2.4.1.2).Three namelessstreamsrun closeto the plant area. The Major Stream has a drainagebasin of 7.44 square miles (ReferencePNPP 2015p) and runs northwestwardwithin 1,000feet of the southwestcornerof the plant.The MinorStream has a drainagearea of only 0.11 squaremiles(ReferencePNPP 2015b)and bordersthe plant area to the east. The DiversionStream has a drainagearea of 0.59 square miles (Reference PNPP2015b)and is locatedeast of the MinorStream.The DiversionStreamdivertsrunoffflow upstreamof the Minor Stream east aroundthe outsideof the securitybarriersand north directly to Lake Erie. The safety-relatedstructuresof the plant are locatedwithin an isolateddrainage area and withinthe drainagebasinof the MinorStream.Finalgradeelevationsin the immediate plantarea vary from 617 to 620 feet (USGS)(USAR,Section2.4.2.2).The floorsat plantgrade are set at Elevation620.5 feet (USGS)(USAR,Section2.4.2.3).Note that the UpdatedSafety Analysis Report (USAR) presentselevationsusing a USGS datum that is equivalentto the NationalGeodeticVerticalDatum of 1929 (NGVD29). For reference,conversionfor the North AmericanVerticalDatum of 1988 (NAVD 88) and for the InternationalGreat Lakes Datum of 1985(IGLD85) are providedin Table1 (ReferencePNPP2015band PNPP2015h).The present-day site layoutis shownin Figure2.0.1.
Table I - Datum Conversions (feet)
NGVD29       NAVD 88       IGLD 85 0.00         -0.72         -0.94 PERRYNUCLEARPOWERPLANT                                                              Page 6 of 42

NTTFRecommendati  on 2.1 (HazardReevaluations)
: Flooding               Revision1 FirstEnergyCorporation                                           M a r c h2 , 2 0 1 6 Figure2.O.1- Present-Day  Site Layout PERRYNUCLEAR    POWERPLANT                                        Page 7 of 42

NTTFRecommendation       2.1 (HazardReevaluations):  Flooding                          Revision1 FirstEnergyCorporation                                                             March2,2016 2.1.GurrentDesignBasis The currentdesignbasisas referencedby the PNPPUpdatedSafetyAnalysisReport(USAR)is providedin Section2.1.The followingis a listof flood-causingmechanismsand theirassociated water surfaceelevationsthat were consideredfor the PNPP currentdesign basis.Section2.3 includesdiscussionof the updateddesignbasisanalyses.
2.1.1. Local IntensePrecipitation(LlP)
The USAR indicatesthat the precipitation  value ol26.7 inchesover a 6-hourperiod,with the maximumhourlyrainfallof 13.1inchesoccurringduringthe first hour,is utilizedfor the LIP analysis.In the case of completeblockageof the storm drainagesystem,the plantsite has been gradedso that overlanddrainagewill occur away from the plantsite buildingsand will not allow the accumulatedstorm water to exceed Elevation620.5 feet (USGS) (USAR, Section2.4.2.3).
2.1.2. Flooding in Streams and Rivers The USAR identifiesa flow rate of 31,250cubic feet per second (cfs) for the Major Stream and 7,000cfs for the MinorStream(USAR,Section2.4.3).The MajorStreamwater surface elevationupstreamof the plantaccessroadforthe PMF was foundto be 624.0feet (USGS) until this surface met the normal depth of flow in the existing stream. This water surface elevationwill safely pass beneaththe railroadbridge (USAR, Section2.4.3.5).The Minor Streamwater surfaceelevationwas foundto be 619.5feet (USGS)(USAR,Figure2.4-B).
2.1.3. Dam Breachesand Failures The USAR identifiesno impoundmentsupstreamof the plant.Therefore,dam failureis not includedas a designcondition(USAR,Section2.4.4).
2.1.4. Storm Surge and Seiche The probablemaximummeteorological      event in Lake Erie resultsin a maximumstillwater surfaceelevationof 580.5 feet (USGS)(USAR,Section2.4.5.2.2).The probablemaximum storm (PMS)was assumedto occur over a72-hour period,duringwhich the winds increased from 20 milesper hourto the maximumspeedof approximately103 milesper hour overthe lake and then decreasedto less than 35 miles per hour in the Perry area (USAR,Section 2.4.s.1.3).
2.1.5. Tsunami Sincethe site is locatedon Lake Erie,an inlandlake,tsunamioccurrenceis not applicable (USAR,Section2.4.6).
2.1.6. lce-lnducedFlooding lce floodingcannotoccurbecauseof the highbluffsbetweenthe buildingsand the lake.Also, safety-relatedonshorebuildingsare set backfrom the top of the 45-foothigh bluffto preclude ice forcesbeinga problem(USAR,Section2.4.7.4).
2.1.7. GhannelMigrationor Diversion Channeldiversionis not applicableto PNPPsinceno coolingwaterchannelsexistfromwhich flow could be diverted(USAR,Section2.4.9).
PERRYNUCLEAR         POWERPLANT                                                      Page 8 of 42

NTTF Recommendation     2.1 (HazardReevaluations): Flooding                           Revision1 FirstEnergyCorporation                                                            March2,2016 2.1.8. CombinedEffect Flood (includingWind-GeneratedWaves)
       \Mnd wave activity,includingrunup,was evaluatedas part of the surge analysis.Runup occurringcoincidentally with the probablemaximumsetupwould extendto about elevation 607.9feet (USGS)on the bluffat the lakeshore(USAR,Section2.4.2.2).
2.1.9. Low Water No water is takenfrom the MajorStreamor Minor Stream.Therefore,low flows in the streams will not affectPNPPoperation.
The UHS for PNPPis LakeErie.Submergedoffshoreintakessupplywaterto the emergency service water pumphouse.All safety-relatedpumps and equipmentare located above elevation586.5 feet (USGS)in the emergencyservicewater pumphouse(USAR, Section 2.4.10).The emergencyservicewater pumphouseand emergencyservicewater pumpsare designedto provideservicecapacityunder all lake level conditionsdown to 565.26 feet (USGS) level caused by the probablemaximumsetdownsuperimposedon the minimum monthlymean lake level(USAR,Section2.4.11.6).Two verticalshaftsconveywater intothe intake tunnel. The intake heads are covered with a velocity cap to prevenUminimize whirlpooling.\Mth the invertsof the intake ports at an average elevationof 552.65 feet (USGS), inflow of sufficient cooling water is assured (USAR, Section 2.4.11.5).The correspondingwater level in the emergencyservice water pump chamber would be at elevation562.09feet (USGS).
2.2. Flood-RelatedChanges to the License Basis Therewere no changesto the flood-relatedlicensebasissincethe initiallicenseissuance.
2.3. Ghangesto the Watershedand Local Area since License lssuance An engineeringchange package (ReferencePNPP ECP 13-0802) implementedin 2015 establishedthe updateddesign basis for the LIP and the floodingin streams and rivers as discussed in the following subsections.The analyses supportingthe engineeringchange packageare based on the 2012 aerialsurvey conductedby Sanborn.The Sanbornsurvey is referencedto the NAVD 88 datum.Therefore,the analyseswere conductedusingthe NAVD 88 datum with final results convertedto a datum consistentwith the plant. The basis of the conversionoriginallyused a generalconversionfrom NAVD 88 to NGVD 29. ConditionReport CR 2015-05079(ReferencePNPPCR 2015-05079)addressedthatthe conversionfactoris more accuratewhen basedon the localonsiteplantmonuments.The conversionwas adjustedby 0.21 feet and a new conversionfactor is used (NAVD 88 + 0.93 ft = Perry Local Datum and IGLD 85
   + 1.15ft = Perry LocalDatum).The resultspresentedhereinare in the Perry LocalDatum.The PerryLocaldatumwas originallybasedon and withinthe tolerancelevelsof the NGVD29 datum.
The engineeringchange package included site modificationsto the Major Stream and establishedthe DiversionStreamto reroutethe south reachesof the Minor Stream as shown in Figure2.0.1.The engineeringchangepackageincorporatedremovalof a portionof the existing abandonedrail line embankmentto the southwestof the rail line bridge crossingthe Major Stream.Removalof the embankmentallowsgreaterconveyanceof flow in the overbanksof the Major Stream,preventingflow from overtoppingthe rail line. Furthermore,the secondaryaccess roadwas raisedto preventany remainingbackwaterfrom overtoppingthe road.This modification identifiedin Figure 2.0.1 resultedin the concentrationof Major Stream runoff to be carried downstreamto Lake Erie,ratherthan contributingto runoffto otherareasof the site.
The engineeringchangepackageincorporatedan upstreamdiversionof the MinorStream.The DiversionStream diverts runoff flow east around the outside of the securitybarriersand north PERRYNUCLEARPOWERPLANT                                                              Page 9 of 42

NTTFRecommendation       2.1 (HazardReevaluations):   Flooding                          Revision1 FirstEnergyCorporation                                                               March2,2016 directlyto Lake Erie. A berm was constructedadjacentto the DiversionStream betweenthe stream and the site. Under PMF conditionsthe berm will maintainall flood water within the DiversionStreamwatershedaway from the site. These modificationssignificantlyreducethe runoffflow receivedby the MinorStream.
Basedon aerialimagesof the watershed,other changesto the watershedincludecommercial developmentwithin the watershedarea, which is a small percentageof the overallwatershed area. The changesto the local area sub-watershed     for PNPP includebuildingsthat have been addedor removedand securitybarrierupgradesthat have been addedto the site since license issuance.
2.3.1. ProbableMaximum Precipitation(ReferencePNPP 2015aand PNPP2016b)
The designbasisrainfallis determined  usingthe U.S.Bureauof Reclamation      Designof Small Dams,SecondEditionguidance(ReferenceUSBR 1973)as referencedby the USAR.The guidanceincorporatesHydrometeorological       Report No. 33 (ReferenceNOAA 1956) and includesa recommendedarea reductionfactorfor smalldrainageareas.The CorrectedPMP utilizingthe area reductionfactor is a front loadedtemporaldistributionevent having 10.5 inchesof rainfalloccurringthe first hour and 21.4 inchesover the entire6-hourperiod.The UncorrectedPMP does not incorporatethe area reductionfactorand is characterizedby 13.1 inchesin the first hour and a 6-houraccumulation    ol 26.7 inches(USAR,Section2.4.3.1).
Table2 providesa descriptionof the PMP events.
Table2-PMPGomparison Duration(hours)                 1      2      3      4      5     6 Uncorrected PMP (inches) 1 3 . 1 1 7 . 1 20.0 22.4 24.6 26.7 CorrectedPMP(inches)          1 0 . 5 13.7 1 6 . 0 1 7 . 9 19.7 2 1 . 4 2.3.2. Local Intense Precipitation(LlP) (ReferencePNPP 2016aand PNPP2016b)
The effectsof LIP were analyzedusing FLO-2Dhydraulicssoftwareto establishthe updated designbasis,includingthe impactsof site streammodifications.      The softwareuses shallow water equationsto route stormwaterthroughoutthe site. The Major Stream is incorporated into the model as a staticwater level boundarycondition.The Minor Streamwatershedis incorporatedinto the modeling.The DiversionStream and associatedwatersheddo not affectthe area of the power block analyzedfor the effectsof LlP. The DiversionStreamand associatedwatershedalso do not affectthe MajorStreamor the MinorStream.The Diversion Streamis not includedin the FLO-2Dmodeling.
Buildingsand securitywall barriersare incorporated   intothe modelas obstructions. The site storm drainage network is incorporated into the model using the S\AAIM software incorporatedinto the FLO-2Dsoftware.The elementsof the roof drain systemthat connect directlyto the storm drainagenetworkor groundwaterare incorporatedinto the model.Roof drains that dischargedirectlyto the ground are not modeled.The site also includesan underdrainsystemthat is independentof the storm drainagenetwork.Sixteenunderdrain manholelocationsare modeledas open inlets.A forthcomingmodificationis in development for the underdrainsystem to allow for manhole structuresto intake surface water. The modificationis requiredto validatethe LIP analysisdiscussedin this section.The plant is currentlyoperatingunder PFA 2015-08036(ReferencePNPP CR 2015-08036)due to the potentialfloodingat the site.
PERRYNUCLEARPOWERPLANT                                                                Page 10 of 42

NTTF Recommendatlon      2.1 (HazardReevaluations): Flooding                         Revision1 FirstEnergyCorporation                                                            March2,2016 FLO-2D softwarepresentsan efficientphysicalprocess model that assess the established conceptsof unsteadyflow analysis.FLO-2Dis a volume conservationflood routingmodel incorporatinga grid system to evaluate topography. FLO-2D solves finite difference approximations  of the continuityand momentumequationsto computeflow in eightdirections for each grid cell.The continuityand momentumequationsare the underlyingequationsfor unsteadyflow analysis.Unsteadyflow is referencedfor streamcoursemodelingby the design basis guidancestandardof the American NationalStandardsInstitute(ANSI) (Reference ANS! N170-1976).
To determinethe associatedfloodingelevations,the CorrectedPMP identifiedin Table 2 is appliedevenlyacrossthe site. No rainfalllossesare includedin the modeling.The effectsof LIP producemaximumwater surfaceelevationsat the power block rangingfrom 619.8 feet Perry Local Datum to 620.7feet Perry Local Datum. In general,the south end of the power blockaroundthe Unit2 TurbineBuildingresultsin highermaximumwatersurfaceelevations.
The resultingmaximumwater surfaceelevationsexceed26 door thresholdelevationsof the powerblock.The maximumwater depthsat the 26 door locationsrangefrom 0.1 feet to 0.4 feet abovethe door thresholdelevationsfor durationsrangingfrom 0.3 hoursto 6 hours.
Maximumwatersurfaceelevationsnorthof the powerblockat the ServiceWaterPumphouse Buildingand the EmergencyServiceWater PumphouseBuildingrangefrom 619.1feet plant datum to 620.0 feet plant datum. The resultingmaximumwater surfaceelevationsdo not exceeddoor thresholdelevationsat the ServiceWater Pumphouse.The resultingmaximum water surface elevations exceed two door thresholds and one louver opening of the EmergencyService Water Pumphouse.The maximum water depths at the three door locationsrangefrom0.3 feetto 0.5 feet abovethe openingelevationsfor durationsof 6 hours.
The doors olthe CirculatingWater pumphousesat each coolingtower are not affectedby the effectsof LIP flooding.
2.3.3. Flooding in Streams and Rivers As a resultof the site modificationsin 2015,the floodingin streamsand riverswere analyzed to establishthe updateddesignbasis.
2.3.3.1. Major Stream (ReferencePNPP2015c,PNPP2015p,and PNPP2015q)
The Major Stream PMF is the flood resultingfrom the 72-hourdurationsite-specific,all-seasonprobablemaximumprecipitation(PMP).Front,one-third,center,two-thirds,and end-loadingtemporaldistributionsare consideredin an effortto capturethe distribution that maximizesrunoff.Cool-seasonalternativesare boundedby the all-seasonresults.
The U.S. Army Corps of Engineers(USACE)HEC-HMShydrologicsoftwareis used to convertrainfallto runoff.A rainfallhyetographis appliedto the MajorStreamwatershed and the NationalResourcesConservationService(NRCS)unit hydrographmethodology is used for rainfall-to-runoff transformation. The unit hydrographis modifiedto account for the effectsof nonlinearbasinresponseby increasingthe peak of the unit hydrograph by one-fifth and reducing the time-to-peakby one-third.An estimated base flow is includedin the analysisand no precipitationlossesare incorporated.
The unsteadyflow simulationmodulewithinthe USACE HEC-RASsoftwareis used to transformthe resultingflow hydrographinto a water surfaceelevationhydrograph.The cross sectionsreflectthe removalof a portionof the rail line embankment.The plant access road and culvert is includedin the model. The upstream rail line bridge is incorporated  intothe model.The upstreamsecondaryaccessroadis includedas an inline PERRYNUCLEARPOWERPLANT                                                            Page11 of 42

NTTF Recommendation     2.1 (HazardReevaluations):   Flooding                        Revision1 FirstEnergyCorporation                                                            March2,2016 structureand all flow overtopsthe road.A boundingwater level in Lake Erie is used as the downstreamboundarycondition.
The area betweenthe rail line spur and the secondaryaccessroad in the overbankon the northeastside of Major Stream would be subjectto the effects of localizedPMP rainfall.The area is evaluatedusing a HEC-HMSlevel-poolstorageroutingmodel.The same site-specificPMP is appliedto the model. No losses are incorporatedinto the analysis.Dischargefrom the area is determinedbasedon weir flow over the rail line.
The analysisdoes not resultin overtoppingof the rail line bridgestructure.Furthermore, MajorStreamfloodingupstreamof the raillineis preventedfromencroachingon adjacent areasby the elevatedembankmentof the rail line spur in the overbankon the northeast side of the MajorStream.The resultingmaximumwater levelsfor the MajorStreamare not adjacentto the powerblock.The raisedsecondaryaccessroad is also not overtopped by the localizedfloodingof the area betweenthe rail line spur and the secondaryaccess road. Therefore,the Major Stream does not contributeto floodingeffectsin the Minor Stream,the DiversionStream,or the power blockarea.The one-third,center,and two-thirds temporal distributionsproduce identicalpeak results and the maximum water levels.The maximumwater surfaceelevationat the rail line bridgestructureis 628.5feet Perry Local Datum,with a maximumflow of 34,200cfs at the bridge.The maximumwater surface elevationproducedfor the area between the rail line spur and the secondary accessroad is 631.4feet PerryLocalDatum.
A boundingapproachis taken in the analysisof the floodingeffectsof MajorStream.The boundingapproachdetermineda more conservativecase betweendesign basis and beyonddesignbasisintoone analysisfor the developmentand implementation      of stream modifications. The boundingPMP appliedis the beyonddesignbasissite-specificPMP as definedin Table3.
Table 3 - Site-SpecificPMP Duration(hours)      1       2      3     4      5       6    12   24   48     72 PMP (inches)       1 2 . 1 1 3 . 6 14.8 1 5 . 9 1 7 . 0 18.1 24.0 25.5 26.1 26.6 In initialappearancesthe UncorrectedHMR 33 PMP appearsto boundthe site-specific PMP as it has the largerhourlyand cumulativestormdurationPMP totals.However,the site-specific PMP is evaluated using S-minute increments based on the Hydrometeorological  ReportNo. 52 (ReferenceNOAA 1982)sub-hourlyratios,whichare not distributedlinearlyas in the designbasis methodologyutilizingHydrometeorological ReportNo. 33. Due to the smalldrainageareasand short responsetime,the sub-hourly PMP incrementsare criticalin determiningthe PMF, by producingmore conservative inflowhydrographsand ultimatelyproduceshigherflow rates.
As shown in Table2, the UncorrectedPMP is greaterthan the CorrectedPMP. Therefore, PMP is a boundingapproachfor the MajorStreamupdateddesign use of the site-specific basisinputrainfall.
2.3.3.2. Minor Stream (ReferencePNPP 2015aand PNPP 2015b)
As a boundingapproach,the Minor StreamPMF is the flood resultingfrom the 48-hour duration UncorrectedHydrometeorological       Report No. 33 PMP. Ratios provided by HydrometeorologicalReport No. 52 are used to define sub-hourly increments.
IntermediateS-minuteincrementalPMP depthsare determinedfor point precipitation(1 PERRYNUCLEARPOWERPLANT                                                            Page 12 of 42

NTTF Recommendation    2.1 (HazardReevaluations):  Flooding                         Revision1 FirstEnergyCorporation                                                          March2,2016 squaremile).Front,one-third,center,two-thirds,and end-loadingtemporaldistributions are consideredin an effortto capturethe distributionthat maximizesrunoff.Cool-season alternativesare boundedby the all-seasonresults.
The USACEHEC-HMShydrologicsoftwareis usedto convertrainfallto runoff.The Minor Stream watershed is subdividedinto three (3) sub-watersheds(a small remainingarea southof the site,the MinorStreamand site area contributingto the MinorStreamat the lateral swale between the two cooling towers, and the small remaining area of the unnamedtributaryeast of the securitybarriers)basedon the topographyof the site and reflectingthe constructionof the DiversionStream.A rainfallhyetographis appliedto the sub-watershedsand NRCS unit hydrographmethodologyis used for rainfall-to-runoff transformation. The unit hydrographsare modifiedto accountfor the effectsof nonlinear basin responseby increasingthe peak of the unit hydrographby one-fifthand reducing the time-to-peakby one-third.An estimatedbase flow is includedin the analysisand no precipitationlossesare incorporated.
The unsteadyflow simulationmodulewithinthe USACE HEC-RASsoftwareis used to transformthe resultingflow hydrographinto a water surfaceelevationhydrograph.One crossingis incorporatedintothe MinorStreammodel.The downstreamLockwoodRoad crossingis modeledas an inlinestructureand all flow overtopsthe road.A bounding water level in Lake Erie is used as a downstreamboundarvconditionfor the HEC-RAS softwareprogram.
The one-third,center,and two-thirdstemporaldistributions  produceidenticalpeakresults and the maximumwaterlevels.The maximumwatersurfaceelevationoccursat the cross sectioncorrespondingto the south end of the Unit 2 TurbineBuildingand is 619.7 feet PerryLocal Datum.The maximumwatersurfaceelevationprofiledecreaseto 618.7feet Perry Local Datum at the cross section correspondingto the north end of the Unit 1 Turbine Building.The maximum flow overtoppingLockwood Road downstreamis approximately1,100 cfs. Peak floodingdoes not overflowthe Minor Stream channel banksand does not reachthe powerblock.
2.3.3.3. Diversion Stream (ReferencePNPP 2015aand PNPP 2015b)
As a boundingapproach,the DiversionStreamPMF is the flood resultingfrom the 48-hour durationUncorrectedHydrometeorological    ReportNo. 33 PMP. Ratiosprovidedby HydrometeorologicalReport No. 52 are used to define sub-hourly increments.
IntermediateS-minuteincrementalPMP depthsare determinedfor pointprecipitation       (1 squaremile).Front,onethird, center,two-thirds,and end-loadingtemporaldistributions are consideredin an effortto capturethe distributionthat maximizesrunoff.Cool-season alternativesare boundedby the all-seasonresults.
The USACEHEC-HMShydrologicsoftwareis usedto convertrainfallto runoff.A rainfall hyetographis appliedto the DiversionStreamwatershedand the NRCS unit hydrograph methodologyis usedfor rainfall-to-runofftransformation. The unit hydrographis modified to accountfor the effects of nonlinearbasin responseby increasingthe peak of the unit hydrographby one-fifthand reducingthe timeto-peak by onethird. An estimatedbase flow is includedin the analysisand no precipitation lossesare incorporated.
The unsteadyflow simulationmodulewithinthe USACE HEC-RASsoftwareis used to transformthe resultingflow hydrographinto a water surfaceelevationhydrograph.The culvertat the outfallof the DiversionStream is assumedto be completelyblockedand modeled as an inline structure.A boundingwater level in Lake Erie is used as a downstreamboundaryconditionfor the HEC-RASsoftwareprogram.
PERRYNUCLEARPOWERPLANT                                                           Page 13 of 42

NTTF Recommendation     2.1 (HazardReevaluations)'  Flooding                          Revision1 FirstEnergyCorporation                                                            March2,2016 The one-third,center,and two-thirdstemporaldistributionsproduceidenticalpeakresults and the maximumwaterlevelsfor the DiversionStream.The PMF inflowhydrographhas a peak of 4,200 cfs. The maximumwater surfaceelevationoccurs at the upstreamfill area and is 629.2feet Perry Local Datum.The fill area and berm are designedwith a crest elevationof 630.9 feet Perry Local Datum. The berm constructedadjacentto the streampreventsfloodingof the site.
The DiversionStreambermwas assessedfor pipingfailureand the potentialfor impact on the Minor Streamresults.The HEC-RASmodelsused to evaluatethe effectsof the PMF are used to assessthe failure effects.The HEC-RASmodels are evaluatedusing unsteady-state flow simulation.
The peak of the failureflow hydrographaddedto the MinorStreammodelingis 670 cfs.
Becauseof the differencein responsetimes for the Minor Stream and the Diversion Stream,the additionof the failureflow hydrographextendsthe durationof floodingin the MinorStream,but the peakwatersurfaceelevationsare identicalto the PMF floodingfor the MinorStream.
2.4. Current Licensing Basis Flood Protection and Pertinent Flood Mitigation Features As a result of the updateddesign basis (ReferencePNPP 2016b),the LIP maximumwater sufface elevationsexceedthe door thresholdelevationsat severallocationsof the power block.
A summaryof the updateddesignbasisresultsare providedin Section2.3.2.The doorschedule for the updateddesignbasis LIP flood hazardresultsis providedin Attachment1. The plant is currently operating under Prompt FunctionalityAssessment (PFA) 2015-08036(Reference PNPP CR 2015-08036)due to the potentialfloodingat the site.
3.0 

==SUMMARY==
OF FLOODHAZARDREEVALUATION NUREGICR-7046,Desrgn-BasrsFlood Estimationfor Site Characterizationat Nuclear Power Plants in the United Sfafes of America (Reference NUREG/CR-7046),by reference to the AmericanNuclearSociety(ANS),states that a single flood-causingevent is inadequateas a design basis for power reactorsand recommendsthat combinationsshould be evaluatedto determinethe highestfloodwaterelevationat the site. For PNPP,the combinationthat produces the highest flood water elevationat the site safety-relatedstructuresis the effects of LlP, as providedbelow.
With the exceptionof the Lake Erie analyses,the beyonddesign basisanalysesare based on the 2012 aerialsurvey conductedby Sanborn.The Sanbornsurvey is referencedto the NAVD 88 datum. Therefore,the analyseswere conductedusing the NAVD 88 datum with final results convertedto a datum consistentwith the plant.The basis of the conversionoriginallyused a generalconversionfrom NAVD 88 to NGVD 29. ConditionReportCR 2015-05079addresses that the conversionfactor is more accuratewhen based on the local onsite plant monuments.
The conversionwas adjustedby 0.21feet and a new conversionfactor is used (NAVD88 + 0.93 feet = Perry Local Datum).
The Lake Erie analyseswere conductedusingthe IGLD85 datumwith final resultsconvertedto a datumconsistentwith the plant.The conversionalso incorporated   the generalconversionfrom NAVD 88 to NGVD 29. Therefore,a conversionadjustmentof 0.21feet is also applicable(IGLD 85 + 1.15feet = PerryLocalDatum).The resultspresentedhereinare in the PerryLocalDatum.
The Perry Local datum is originallybased on and within the tolerancelevelsof the NGVD 29 datum.
PERRYNUCLEARPOWERPLANT                                                             Page 14 of 42

NTTF Recommendation      2.1 (HazardReevaluations). Flooding                         Revision1 FirstEnergyCorporation                                                             March2,2016 The beyonddesign basis Calculation50:66.000 PNPP SiteModificationsBeyond DesignBasrs Local lntense Precipitation(Reference PNPP 2016c) defines the maximum water surface elevationsresultingfrom the LIP event at the power block. The maximum water surface elevationsat the powerblockdue to the LIP event rangefrom 619.9feet Perry Local Datumto 621.3 feet Perry Local Datum. The LIP maximumwater surfaceelevationsexceed the door thresholdelevationsat severallocationsof the powerblock.The elevationsof the site doorsare referencedto the Perry Local Datum.
The methodologyused in the floodingreevaluationfor PNPP is consistentwith the following standardsand guidancedocuments:
     . NRC StandardReviewPlan,NUREG-0800,revisedMarch 2OO7             (ReferenceNUREG-O8OO)
NUREG/CR-7046,       "Design-BasisFlood Estimationfor Site Characterizationat Nuclear Power Plants in the United States of America," dated November 2011 (Reference NUREG/CR-7046)
NUREG/CR.6966,      "TsunamiHazardAssessmentat NuclearPowerPlantSitesin the United Statesof America", dated March2009 (ReferenceNUREG/CR-6966)
        "AmericanNationalStandardfor DeterminingDesign Basis Floodingat Power Reactor Sites'],dated July 28, 1992(Reference ANSI/ANS-2.8-1992)
NEI Report12-08,"Overviewof ExternalFloodingReevaluations"        (ReferenceNEI August 2012)
NRC JLD-ISG-2012-06,     "Guidancefor Performinga Tsunami,Surge or SeicheFlooding HazardAssessment",Revision0, dated January4, 2013 (ReferenceJ LD-lSG-2O         12-06)
     . NRC JLD-lSG-2013-01,"Guidancefor Assessmentof Flooding Hazards due to Dam Failure",Revision0, datedJuly 29, 2013 (ReferenceJLD-lSG-2013-01)
The flood hazardreevaluation,   includinginputsand methodology,are beyondthe currentPNPP design and licensebasis.Consequently,the analyticalresultsprojectbeyondthe capabilityof the current design basis. The following provides the flood-causingmechanismsand their associatedwater surfaceelevationsthat are consideredin the PNPP flood hazard reevaluation.
3.1. Flooding in Streams and Rivers (ReferencePNPP 2015a,PNPP 2015b, PNPP 2015c, PNPP2015i,PNPP2015n,PNPP 2015o,PNPP2015p,and PNPP2015q)
The updateddesignbasisanalysesincorporated       the beyonddesignbasisevents.Therefore,the beyonddesignbasisanalysesare identicalto the updateddesignbasisanalysesfor the Major Stream,the MinorStream,and the DiversionStream.The PMF in riversand streamsadjoining the site is determinedby applyingthe PMP to the drainagebasin in which the site is located.
Becausethe watershedsanalyzedare small,the representative     PMP is pointprecipitation.
The PMF is basedon a translationof PMP rainfallin the watershedto flood flow. The PMP is a deterministicestimateof the theoreticalmaximumdepth of precipitationthat can occur at a certaintime of year for a specifiedarea at a particulargeographicallocation.A rainfall-to-runoff transformation                                           basedon the topographicand drainage function,as well as runoffcharacteristics, system networkcharacteristicsand watershedproperties,are neededto appropriatelydevelop the PMF hydrograph.The PMF hydrographis a time historyof the dischargeand servesas the inputparameterfor other hydraulicmodelsthat developthe flow characteristics,   includingflood flow and elevation.
PERRYNUCLEARPOWERPLANT                                                              Page 15 of 42

NTTF Recommendation     2.1 (HazardReevaluations):  Flooding                            Revision1 FirstEnergyCorporation                                                               March2,2016 The PMF is a functionof the combinedeventsdefinedin NUREG/CR-7046          for floodscausedby precipitationevents.Cool-seasonalternativesare determinedto be boundedby the all-season alternative.
Alternative1 - Combinationof:
       . Mean monthlybaseflow
       . Mediansoil moisture
       . Antecedentor subsequentrain:the lesserof (1) rainfallequalto 40 percentof PMP and (2) a 500-yearrainfall
       . The All-SeasonPMP
       . Waves inducedby 2-yearwind speedappliedalongthe criticaldirection Alternative2- Combination   of:
o  Mean monthlybaseflow
       . Snowmeltfrom the probablemaximumsnowpack
       . A 1O0-year, snow-seasonrainfall o  Waves inducedby 2-yearwind speed appliedalong the criticaldirection Alternative3 - Combinationof.
o  Mean monthlybaseflow o  Snowmeltfrom a 1OO-year    snowpack o  Snow-seasonPMP
       . Waves inducedby 2-yearwind speedappliedalongthe critical 3.1.1. Basis of Inputs:
The inputsused in the PMP and PMF analysesare basedon the following:
All-SeasonPMPAnalysis o PNPP,MajorStream,MinorStream,and DiversionStreamwatershedlocations;
          . ProbableMaximumPrecipitation      Studyfor the Stateof Ohio; o Site-specific,all-seasonPMP pointrainfallshort durationestimatesdeterminedusing a storm-basedapproach in accordancewith National Oceanic and Atmospheric Administration(NOAA) Hydrometeorological      Reportsand the World Meteorological Organizationapproach; o UncorrectedHydrometeorological     ReportNo. 33 PMP pointrainfallestimates;
          . Hydrometeorological    ReportNo. 52 ratiosfor PMP point rainfallestimatesfor durations less than t hour.
PMF Analysis-Hydrologicand HydraulicAnalysis
          . PNPP, Major Stream, Minor Stream, and DiversionStream watershed areas,boundariesand configurations; o Precipitationfor the subjectwatershedarea;
          . Baseflow:Historicflowratedata collectedby USGSatgauge 04212100on the Grand River,which is used to determinethe base flow for the Major Stream,MinorStream, and DiversionStream; PERRYNUCLEARPOWERPLANT                                                               Page 16 of 42

NTTF Recommendation      2.1 (HazardReevaluations):    Flooding                           Revision1 FirstEnergyCorporation                                                                March2,2016 a  Sitetopographydevelopedfrom aerialphotogrammetry; a  Digitalterrainmodel(DTM)developedfrom site topography; a  Manning's roughness coefficientsare based on a visual assessment of aerial photography   and selectedusingstandardapplicableengineeringguidancereferences; and a  Site data for the rail line bridgecrossingthe MajorStream; a  Construction   drawingsand as-builtdrawingsfor modifications  to the MajorStreamrail line embankment,the secondaryplantaccessroad,and the DiversionStream.
3.1.2. Gomputer Software Programs PMP o   ArcGlSDesktop10.1
           . MicrosoftExcel2007 and 2013 PMF analysis
           . AutoCADCivil 3D 2012
           . ArcGlSDesktop10.0 o   ArcGlSDesktop10.1
           . HEC-HMS3.5
           . HEC-RAS4.1
           . HEC-GeoRAS10.1
           . MicrosoftExcel2010 and 2013 3.1.3. Methodology The site-specific  PMP analysisincludedthe followingsteps:
           . An extensivestorm searchto identifystormswhich could be used for PMP studiesin the region.
           . Largest precipitationevents which were determinedto be transpositionableto the PNPPsite were then maximizedin-placeand transpositioned       to the site.
Site-Specific,All-Season PMP All the storms evaluatedin the previousPMP studiesin the region,and consideredto be transpositionable   to the PNPP site were evaluated.This resultedin 20 events that were evaluatedto determinethe shortduration1-hourdepthfor the site-specific,       all-seasonPMP.
Ten of these storms were previously analyzedin Hydrometeorological         Report No. 33 and Hydrometeorological     Report No. 51 (ReferenceNOAA 1978) by the National Weather Service(NWS)and the USACE.The remaining10 were analyzedfor the ProbableMaximum Precipitation Studyfor the Stateof Ohio.
Eachstormis then maximizedby an in-placemaximization       factorto representwhat the storm would have looked like had the atmosphericconditionsand moistureavailablefor rainfall productionbeen at maximum levels when the storm occurredversus what was actually observed.The in-placemaximizedvaluesfor each stormare then adjustedto transposethe storm from its originallocationto the PNPP site. The transpositioncalculationadjustsfor ditferencesin availablemoistureat the site versus the originalstorm location.The ratiosto determinesub-hourlyincrementsin Hydrometeorological        ReportNo. 52, are appliedto the resultingsite-specific,1-hourPMP estimateto determine5-, 15-, and 3O-minuteduration estimates.
PERRYNUCLEARPOWERPLANT                                                                Page 17 of 42

NTTF Recommendation     2.1 (HazardReevaluations):   Flooding                         Revision1 FirstEnergyCorporation                                                            March2.2016 The PMF analysisincludesthe followingsteps:
           . Delineatewatershedand sub-watershedsand calculatesub-watershedareas for inputintothe USACEHEC-HMSrainfall-runoff      hydrologiccomputermodel.
o Determinerainfall.
           . EstimateHEC-HMSrainfall-runoff      model input parameters:NRCS unit hydrograph method.
           . Adjust unit hydrographto accountfor the effectsof nonlinearbasinresponse.
           . PerformPMF simulationwith PMP inputusingHEC-HMSmodelwith no precipitation losses.
           . Estimatewater surface elevationusing HEC-RASunsteady-statemodel by using runotfhydrographfrom the HEC-HMSmodelas an input.
Watershed Delineation For the purposesof the hydrologicmodelingeffort,the MajorStreamis evaluatedusingone watershed.The MinorStreamwatershedis subdividedintothree(3) sub-watersheds         (a small area southof the site,the MinorStreamand site areacontributing   to the MinorStreamat the lateralswalebetweenthe two coolingtowers,and the small remainingarea of the unnamed tributaryeast of the securitybarriers)based on the topographyof the site. The Diversion Streamis evaluatedusing one watershed.
All-SeasonPMP For the Major Streamanalysis,the all-seasonPMP is determinedby usingthe site-specific PMP estimatesdefinedby the PMP studyfor the Stateof Ohio (ReferenceODNR 2013)for durationsfrom 6to72 hours.The PNPPsite-specific      analysisdefinesthe PMP estimatesfor t hour and sub-hourlyincrements.IntermediateS-minuteincrementalPMP depths are determinedfor pointprecipitation  (1 squaremile).
As a boundingapproach,the Minor Stream and DiversionStream are modeledusing the UncorrectedHydrometeorological     Report No. 33 all-seasonPMP. Hydrometeorological ReportNo. 33 definesPMP estimatesfor durationsfrom t hourto 48 hours.Ratiosprovided by HydrometeorologicafReport No. 52 are used to define the sub-hourly increments.
IntermediateS-minuteincrementalPMP depths are determinedfor point precipitation(1 squaremile).
The temporaldistributionof the PMP is arrangedin accordancewith the recommendations in Hydrometeorological   Report No. 52, wherein individualrainfall incrementsdecrease progressivelyto eitherside of the greatestrainfallincrement.Varioustemporaldistributions for each rainfallscenarioare then evaluatedto furthermaximizethe runoff.Front,one-third, center, two-thirds,and end-loadingtemporaldistributionsare consideredin an effort to capturethe distributionthat maximizesrunoff.
Note that an antecedentrainfalloccurs prior to the all-seasonPMP. Becauseof the small drainageareasof the MajorStream,MinorStream,and DiversionStreamand the dry period betweenthe antecedentstorm and the PMP event,the streamsreturnto baseflowconditions priorto the PMP event. Therefore,the antecedentstorm is determinedto have no influence on the PMP storm.
HydrologicModel (HEC-HMS)
The PMF is the flood resultingfrom the all-seasonPMP. USACE HEC-HMS hydrologic software is used to convert rainfallto runoff.A rainfallhyetographis applied to the Major Streamwatershed,the DiversionStreamwatershed,and each sub-watershedof the Minor PERRYNUCLEARPOWERPLANT                                                            Page 18 of 42

NTTF Recommendation     2.1 (HazardReevaluations): Flooding                             Revision1 FirstEnergyCorporation                                                              March2,2016 Stream and transformedto runoff using unit hydrographmethodology.Generally,a unit hydrographis developedusinghistoricaldata obtainedfrom variousrain and streamgauges in the watershed.The Major Stream,Minor Stream,and DiversionStreamwatershedsare ungauged.Thus, no historicalobservationsare availableto use as a basisto createa unit hydrograph.Therefore,a syntheticunit hydrographis developed.NRCS unit hydrograph methodologyis usedfor rainfall-to-runofftransformation.
ANSI/ANS-2.8-1992     suggeststhat base flow should be based on mean monthlyflow. As mean monthlyflow is not availablefor the MajorStream,MinorStream,or DiversionStream, the base flow is approximatedbased on the mean monthlyflow in an adjacentwatershed.
The USGSgaugestationon the GrandRivernearPainesville,        OH is used.The GrandRiver has the same hydrologicunit code accountinglevelas the MajorStream,MinorStream,and DiversionStreamand are adjacenthydrologicunitcodesub-watershed          levels.Therefore,the riversand streamsexhibitsimilarwatershedcharacteristics,   and it is an acceptableapproach to use the base flow informationfor the Grand Riveras the basisfor estimationof the base flow for Major Stream,Minor Stream,and DiversionStream.
To conservativelymaximize runoff, f,o               losses are                  into the seasonPMF alternativeanalysis.
The unit hydrographsfor the Major Stream watershed,each sub-watershedof the Minor Stream,and the DiversionStreamare modifiedto accountfor the effectsof nonlinearbasin response in accordancewith NUREG/CR-7046.The peak of each unit hydrographis increased by one-fifth and the time-to-peak is reduced by onethird. The remaining hydrographordinatesare adjustedto preservethe runoff volume to a unit depth over the drainagearea.
The area betweenthe rail line spur and the secondaryaccess road in the overbankon the northeastside of Major Streamwould be subjectto the effectsof localizedPMP rainfall.The area is evaluatedusinga HEC-HMSlevel-poolstorageroutingmodel.The samesite-specific PMP is appliedto the model.No fossesare incorporatedinto the analysis.Dischargefrom the area is determinedbasedon weir flow over the rail line.
HydraulicModel (HEC-RAS)
The unsteadyflow simulationmodule within the USACE HEC-RASsoftware is used to transformthe resultingflow hydrographsfrom the controllingalternativeinto a water surface elevationhydrographunderunsteadyflow conditions.
Channeland floodplaingeometryfor the MajorStream,the MinorStream,and the Diversion Stream is modeled by developingcross sections of the streams. The cross sections are placedat locationsthat definegeometriccharacteristicsof the streamand overbanks.Cross sectionsare also placedat representative locationswherechangesoccurin discharge,slope, shape,and roughness,as well as at hydraulicand inlinestructures(e.9.,bridgesculverts).
Streambanks,blockedobstructions,and ineffectiveflow areas are also incorporatedinto the HEC-RASmodel.
The cross sections of the Major Stream reflect the removal of a portion of the rail line embankment.Three crossingsare incorporatedinto the Major Stream model. The plant access road includesa culvertand is modeledusing topographicsurvey data and USAR data. The upstream rail line bridge is modeled using topographicsurvey data and site records.The upstreamsecondaryaccessroad is includedas an inlinestructureand all flow overtopsthe road.
PERRYNUCLEARPOWERPLANT                                                               Page 19 of 42

NTTF Recommendation      2.1 (HazardReevaluations):  Flooding                        Revision1 FirstEnergyCorporation                                                          March2,2016 One crossingis incorporated  intothe MinorStreammodel.The downstreamLockwoodRoad crossingis modeledas an inlinestructureand all flow overtopsthe road.The culvertat the outfallof the DiversionStreamis assumedto be completelyblockedand modeledas an inline structure.
The PMF flow hydrographsobtainedfrom the time-seriesoutflowresultsof the HEC-HMS modelsare enteredinto the HEC-RASmodels.A boundingwater level in Lake Erie is used as a downstreamboundaryconditionfor the HEC-RASsoftwareprogram.
The DiversionStreambermwas assessedfor failureand the potentialfor impacton the Minor Stream results.Failureof the berm is assumedto occur during the peak water surface elevationin the DiversionStream,ata locationthat maximizesthe depth.Becausethe berm crest does not overtopduringthe PMF, pipingfailureis consideredto be the failuremode.
No tailwateris assumedfor the analysis.Breachparametersare selectedin accordancewith JLD-ISG-2013-01to maximizethe breach and the resultingfailureftow hydrograph.The HEC-RAS models used to evaluatethe effects of the PMF are used to assess the failure effects. The berm failure is modeled as a lateral breach in the HEC-RAS model for the DiversionStream.The resultingfailureflow hydrographis then addedto the HEC-RASmodel for the Minor Stream. The HEC-RAS models are evaluated using unsteady-stateflow simulation.
3.1.4. Results MaiorStream The Major Stream is not directlyadjacentto PNPP safety-relatedstructures.The analysis does not resultin overtoppingof the raillinebridgestructure.MajorStreamfloodingupstream of the rail line is preventedfrom encroachingon adjacentareas in the overbankon the northeastside by the elevatedembankmentof the raillinespur.The raisedsecondaryaccess road is also not overtoppedby the localizedfloodingof the area betweenthe rail line spur and the secondaryaccessroad.Therefore,the MajorStreamdoes not contributeto flooding effectsin the Minor Stream,the DiversionStream,or the power block area. The one-third, center,and two-thirdstemporaldistributions  produceidenticalpeakresultsand the maximum water levels.The maximumwater surfaceelevationat the rail line bridgestructureis 628.5 feet Perry Local Datum, with a maximum flow of 34,200 cfs at the bridge. The resulting maximum water levels for the Major Stream are not adjacent to the power block. The maximumwater surface elevationproducedfor the area in the overbankon the northeast side of MajorStreambetweenthe rail line spur and the secondaryaccessroad is 631.4feet Perry Local Datum. The secondaryaccess road was raisedto exceed the maximumwater surface elevationas part of the modificationsperformedin 2015. Therefore,overflowfrom the area is maintainedwithin the Major Stream watershed.As previouslyindicated,the updateddesignbasisanalysesincorporated      the beyonddesignbasisevents.Therefore,the beyonddesignbasisresultsfor the MajorStreamare identicalto the updateddesignbasis.
MinorStream The one-third,center,and twothirds temporaldistributionsproduceidenticalpeak results and the maximumwater levels.The maximumwater surfaceelevationoccursat the Unit 2 Turbine Buildingand is 619.7 feet Perry Local Datum. The maximum flow overtopping LockwoodRoad downstreamis 1,100 cfs.
The maximumwater surfaceelevationsat each safety-relatedstructureadjacentto the Minor Streamfloodingare providedin Table 4. As previouslyindicated,the updateddesign basis PERRYNUCLEARPOWERPLANT                                                           Page 20 of 42

NTTF Recommendation      2.1 (HazardReevaluations):  Flooding                         Revision1 First EnergyCorporation                                                             March2,2016 analysesincorporatedthe beyonddesignbasisevents.Therefore,the beyonddesignbasis resuftsfor the MinorStreamprovidedin Table4 are identicalto the updateddesignbasis.
Table 4 - Minor Stream Beyond Design Basis Flooding Elevations and Durationsat PNPP Maximum Water           FloodDurationabove Surface Elevation (feet      620.5feet (Perry Structure            Perry Local Datum)           LocalDatum)
Unit2 TurbineBuilding                619.7                      nla Unit2 AuxiliaryBuilding              619.4                      nla Unit2 ReactorBuilding                618.9                      nla Intermediate Building                618.9                      nla Unit 1 ReactorBuilding               618.9                      nla Unit1 AuxiliaryBuilding              618.9                      nla Unit1 TurbineBuilding                618.7                      nla DiversionStream The one-third,center,and twothirds temporaldistributionsproduceidenticalpeak results and the maximumwater levelsfor the DiversionStream.The PMF inflowhydrographhas a peak of 4,200 cfs. The maximumwater surfaceelevationoccursat the upstreamfill area and is 629.2feet Perry Local Datum.The fill area and berm are designedwith a crestelevation of 630.9 feet Perry Local Datum. The berm constructedadjacent to the stream prevents floodingof the site.
Failureof the DiversionStreamberm resultsin a failureflow hydrographwith a peak of 670 cfs addedto the Minor Streammodeling.Becauseof the differencein responsetimes for the MinorStreamand the DiversionStream,the additionof the failureflow hydrographextends the durationof flooding in the Minor Stream, but the peak water surface elevationsare identicalto the PMFfloodingidentifiedin Table4. As previouslyindicated,the updateddesign basisanalysesincorporatedthe beyonddesignbasisevents.Therefore,the beyonddesign basisresultsfor the DiversionStreamare identicalto the updateddesignbasis.
3.2. Dam Assessment (ReferencePNPP 2015d) 3.2.1. Basis of Inputs Inputsused for the dam assessmentevaluation
            . PNPP,MajorStream,and MinorStreamwatershedlocations.
            . USGStopographic   quadranglemaps.
o   The USACE NationalInventoryof Dams (NlD) database used to identify any watersheddams.
3.2.2. Gomputer Software Programs
            . None PERRYNUCLEARPOWERPLANT                                                              Page 21 of 42

NTTF Recommendation       2.1 (HazardReevaluations):Flooding                         Revision1 FirstEnergyCorporation                                                            March2.2016 3.2.3. Methodology The PNPP Major Stream, Minor Stream, and DiversionStream watershed locationsare approximatedusing USGS topographicquadranglemaps. The USACE NID databaseis reviewedto determinethat no dams are located in the Major Stream, Minor Stream, or DiversionStreamwatersheds.
3.2.4. Results No dams are locatedin the combinedwatershedof the Major Stream,Minor Stream,and DiversionStream.Therefore,dam failureis not applicable.
3.3. lce-lnducedFlooding(ReferencePNPP2015e)
As identifiedby NUREGICR-7046,icejams and ice damscan form in riversand streamsadjacent to a site, and may leadto floodingby two mechanisms:
o   Collapseof an icejam or an ice dam upstreamof the site can resultin a dam breach-like flood wave that may propagateto the site; and
       . An ice jam or an ice dam downstreamof a site may impoundwater upstreamof itself, thus causinga flood via backwatereffects.
3.3.1. Basis of Inputs
           . USACEice jam database.
o   Site topography.
o   Bridge geometry (upstream and downstream of PNPP) determined using site topographyand site records.
3.3.2. Computer Software Programs
           . MicrosoftExcel 2013 3.3.3. Methodology Per NUREG/CR-7046,ice-inducedfloodingis assessedby reviewingthe USACE ice jam databaseto determinethe most severe historicalevents that have occurred.No historical records are availablefor the Major Stream, Minor Stream, or DiversionStream. The nonexistenceof ice jam recordsis explainedby the absenceof streammonitoringstations on the two streams. Based on ice jam occurrences recorded for rivers within adjacent watersheds,it is determinedthat ice jam eventsare possible.
The maximum ice jam is determinedby selectingthe historicevent that producedthe maximum flood stage relative to the normal water surface elevation at that location.
Regardlessof the specificconditionsthat producedthe historicflood stage at a specific assumedto representthe ice jam.
location,the full heightis conservatively Historicalice jam data for the adjacentwatershedsfor the Grand River and the Ashtabula Riverare considered.Althoughno recordsare availablefor the actualheightof the ice jams, the maximumrecordedstage is used to representthe ice jam. The ice jam is transposedto the site and comparedwith otherfloodingcausingmechanisms.
3.3.4. Results The maximumreportedice jam stage in the regionalvicinityof PNPP is estimatedto be 18 feet. For the MinorStream,no significantupstreamcrossingsor structuresare presentthat PERRYNUCLEARPOWERPLANT                                                            Page 22 of 42

NTTF Recommendation     2.1 (HazardReevaluations):  Flooding                           Revision1 FirstEnergyCorporation                                                             March2.2016 couldfacilitatesignificantice jam formation.The only upstreamaccessroad is now located in the DiversionStreamwatershed.The accessroadis an unimprovedroadwith a low profile and a small drainagestructure.The elevationcharacteristics    of the area at that drainage structureindicatein the unlikelyeventan ice jam did occur,it would be limitedto less than 2 feet in height.Furthermore, any icejam and subsequentfailurewouldonly releasea flow rate at the maximumcapacityof the smalldrainagestructure.By qualitativecomparison,the PMF analysisincludesrainfallrunoffcontributionfrom the entiredrainagearearesultingin a peak flow rate magnitudesgreaterthan the capacityof a small drainagestructure.Any upstream icejam collapseis boundedby the PMF analysis.
The only downstreamlocationon the MinorStreamconduciveto an ice jam is at Lockwood Road.The assumedtransposition      of the maximumicejam would producea maximumwater surfaceelevationof 608.9 feet Perry Local Datum.Assumingthe culvertat LockwoodRoad is completelyblocked,any coincidentflow would eventuallyovertopLockwoodRoad. The PMF analysisfor MinorStreamassumesthe LockwoodRoad culvertis completelyblocked and the PMF overtopstheroad.Therefore,by qualitativecomparisonwith the PMF analysis, any downstreamice jam floodingis boundedby the PMF analysis.
Downstreamice jam floodingwas not specificallyexaminedfor the DiversionStream. The DiversionStreamis locatedeast of the Minor Streamand is not adjacentto the immediate area of the plant.Similarto the Minor Stream,the downstreamend of the DlversionStream also has a culvert.Assumingthe culvertis completelyblocked,any coincidentflow would eventuallyovertopthe culvertembankment.The culvertembankmentis significantlylower than the berm locatedbetweenthe DiversionStreamand the site.
For the MajorStream,the upstreamrail line bridgehas a clearheightof greaterthan 20 feet from naturalgradeto the bottomof the low chord.The assumedtransposition    of the maximum estimated18 feet ice   jam would allow normalflows overtoppingthe ice   jam to flow through the remainingbridgeopeningbelowthe low chord.In addition,flow would pass throughthe removedportionof the abandonedrail line embankmentto the southwestof the rail line bridgecrossingthe Major Stream.Any ice jam failureat this locationwould be transposed downstreamto the plant accessroad.
The accessroadincludesa largeellipticalculvert35'-11" by 23'-5".Basedon sitetopography the clearheightis approximately18 feet abovethe normalwatersurfaceelevation.Assumed transpositionof the maximumestimated18 feet ice jam would producea maximumwater surfaceelevationbelowthe plantaccessroad.Assumingthe culvertat the plantaccessroad is completelyblocked,any coincidentflow would eventuallyovertopthe plant accessroad.
The PMF analysis for Major Stream results in overtoppingof the plant access road.
Therefore,by qualitativecomparisonwith the PMF analysis,any ice jam floodingis bounded by the PMF analysis.
The downstreamsedimentcontrolstructureis the only other locationpossiblyconduciveto an ice jam. The assumedtranspositionof the maximumice jam would producea maximum water surfaceelevationof 604.9feet Perry Local Datum.The resultsof the PMF analysesfor the Major Streamexceedthe estimatedice jam elevation.
lce-inducedfloodingat PNPPis boundedby the PMF analyses,and no furtherconsideration is required.
PERRYNUCLEARPOWERPLANT                                                             Page 23 ol 42

NTTF Recommendation       2.1 (HazardReevaluations):  Flooding                                Revision1 FirstEnergyCorporation                                                                     March2,2016 3.4.GhannelMigrationor Diversion(ReferencePNPP2015e)
NUREG/CR-7046        indicateshistoricalrecordsand hydrogeomorphological         data shouldbe used to determinewhetheran adjacentchannel,stream,or riverhas exhibitedthe tendencyto migrate towardsthe site.
3.4.1. Basis of Inputs o    Ohio Departmentof NaturalResourcessurficialgeologymap (ODNR2006) o    USGS topographicquadranglemaps, includingaerial images (ReferenceUSGS 1943,USGS 1992,USGS1994,and USGS2010) 3.4.2. Computer Software Programs
            . None 3.4.3. Methodology Surficialgeologyalong with historicand currenttopographicquadranglemaps that include aerial images are reviewedto examinethe conditionand alignmentof riversand streams over time.
3.4.4. Results The surficial geology map indicates the area in the immediate vicinity of PNPP is characterizedby layersof sand, silt and clay, and till or clayeyto silty till over shale bedrock.
This characterizationrepresentsthe entirewatershedof the Minor Stream and the majority of the Major Stream.The upstreamportionof Major Stream is characterizedby additional areasof sandand gravelor clayeyto siltytill overshalebedrock.Alluviumor organicmaterial, whichare moresusceptibleto erosion,are not presentin the MajorStream,the MinorStream, or DiversionStreamwatersheds.
Topographicmaps for the yearsof 1905 (Reprinted1943),1960 (Revised1992),1994,and 2010 are reviewedto assess historicchannelmigration.The Minor Streamwas reroutedas part of the plantconstruction.In 2015 site modifications   constructedthe DiversionStreamto divert runoff flow upstream of the Minor Stream, east around the outside of the security barriers,and north directlyto Lake Erie. The topographicand aerial images provide no evidenceof oxbows, braidedstreams,or alluvialfans that could indicatea potentialfor channelmigrationof the MajorStreamor the Minor Stream.The DiversionStreamis newly constructedand does not exhibitevidenceof a potentialfor channelmigration.The Diversion Stream is locatedeast of the Minor Streamand is not adjacentto the immediatearea of the plant.
The streamsin the vicinityof PNPPdo not exhibitcharacteristics     of channelmigration.
3.5.Storm Surge (ReferencePNPP20151,PNPP20159,PNPP2015h,PNPP2015k,and PNPP2015t)
Probable Maximum Storm Surqe (PMSS) fn accordancewith JLD-ISG-2012-06,      all coastalnuclearpower plant sites and nuclearpower plant sites adjacentto cooling ponds or reservoirssubject to potentialhurricanes,windstorms and squall lines must considerthe potentialfor inundationfrom storm surge and waves.JLD-ISG-2012-06also suggeststhat for the storm surge hazardassessment,historicalstorm events in the regionshouldbe augmentedby a syntheticstormparameterized           to accountfor conditions PERRYNUCLEARPOWERPLANT                                                                     Page 24 of 42

NTTF Recommendation      2.1 (HazardReevaluations):   Flooding                          Revision1 FirstEnergyCorporation                                                              March2,2016 moreseverethanthosein the historicalrecordsand consideredreasonablypossibleon the basis of technicalreasoning.
3.5.1. Basis of Inputs The inputsused in PMSSanalysisare basedon the following:
           . Historicalwind and pressurefield data from NOAAfor the Great Lake Region
           . Probablemaximumwindstorm(PMWS)
           . Lake Erie bathymetryfrom the NOAAgeophysicaldatabase
           . SupportingGIS data 3.5.2. Computer Software Programs
           . ArcMap10.1
           . Delft3D software suite (Delft3D-FLOWRevision 1, Delft3D-WAVERevision 0, Delft3D-RGFGRID      Revision1, and Delft3D-QUICKIN Revision1) o   lGLD85HeightConversionTool o   R ComputerLanguage2.15.1
           . MicrosoftExcel2007,2010,and 2013 3.5.3. Methodology Severalphysicalprocessescontributeto the generationof a stormsurge.The contributionof wind to a stormsurgeis oftencalledwind setup.Wind blowingoverthe watercausesa shear stressthat is exertedon the surfaceof the water, pushingwater in the directionof the wind.
Atmosphericpressuregradientsare anotherforcingmechanismthat contributesto changes in water level, as water is forced from regionsof high atmosphericpressuretoward regions of low atmosphericpressure.
The followingdescribesthe methodologies     used in the PMSScalculation:
Development of the PMWS The PMWS storm-basedapproachis specificto the characteristicsof the site. Past extreme events in a region are analyzedand consideredtranspositionable.      As part of the PMWS, differentstormtypes(suchas synoptic,squallline,and hybrid)that impactedthe GreatLakes regionare consideredin orderto determinethe stormeventthat will generatethe maximum surge and seiche.Each storm'sinput parametersare quantifiedand plottedbased on the locationof low/highpressurecenters,concurrentwind/pressurefields, and how they evolve throughtime and space.
Most of the synopticstormsoccur in associationwith deep areasof low pressurewhich move throughthe regionfrom southwestto northeast.The generalsynopticpatternis one in which the deep area of low pressureresults in a very strong pressuregradientforce between its low pressurecenterand a correspondingregionof higherpressureto the north or west. The larger the gradient between the two systems over a given distance is, the stronger the resultingwinds.
Squallline (or derecho)eventscreatea widespreadstraight-line    windstormthat is associated with a fast-movingband of severethunderstorms.These winds have producedsome of the highestinstantaneous   gustson record,but lastfor only a shorttime (lessthan 30 minutes)at a givenlocation.The shortdurationof theseevents,as they quicklytraversea givenlocation, means they will not controlthe PMSS. Further,these eventsdo not occur within deep low pressuresystemsor remnanttropicalsystems.Therefore,their wind and pressuredata are PERRYNUCLEARPOWERPLANT                                                              Page 25 of 42

NTTF Recommendation     2.1 (HazardReevaluations):  Flooding                           Revision1 FirstEnergyCorporation                                                            M a r c h2 , 2 0 1 6 not combinedwith the otherstormtypes in this analysis,as this would resultin a PMWSthat is not physicallypossible.
Althoughdeep low pressuresystemsoften producethe longestdurationlarge-scalewinds, other storm types also produce strong winds over the region. ln rare cases, land-falling tropical systems along the Gulf Coast or Atlantic Seaboard move inland across the Appalachiansor up the Mississippiand Ohio Rivervalleys.By the time these stormsreach the Great Lakes region,they are no longertropicalsystems,but insteadhave transitioned into extra-tropicalcyclones.Their general circulationand center of deep low pressure persists. Much like the deep low pressure scenario previouslydiscussed,strong and persistentwindscan result.The remnantsof HurricaneHazel(October1954)and Hurricane Sandy (October2012) are classicexamplesof this stormtype. This storm scenarioprovided some of the strongestwinds from the northwestthroughthe northeastdirectionsover Lake Erie (withdurationsof 12 hoursor more).
Delft3DGalibration The Delft3Dhydrodynamicmodelis set up usingthe Delft3Dsoftwaresuite.The wave setup contribution to the total stormsurgevaluesare modeledby couplingthe Delft3D-WAVEand Delft3D-FLOW    surge models.The generalapproachto stormsurge modelingusingcoupled Delft3D-FLOWand Delft3D-WAVEmodelsconsistsof the followingsteps:
      . Developingthe bathymetricdatasetand modelgrid mesh for the lake system;
      . Assemblinginputfilesfor atmosphericforcing(windand pressurefields);
Assemblinginputfilesfor initialwater level,boundaryconditions,and the physicaland numericalparametersof the model; Assemblingmeasuredwater levelsand wave data for modelcalibrationand verification; Testingand refiningthe initialmodelsetup; Validatingthe model for historicalextremestorm events;and Assessingmodel sensitivityto variousfactorsand adjustableparameterssuch as bottomfrictionand wind drag coefficient.
The Delft3Dmodelis calibratedbasedon historicaldata obtainedfrom NOAA meteorological and water levelrecordingstationslocatedin the Lake Erie region.
Reviewof historicaldata showsthat variouspartsof Lake Erie responddifferentlyto any one particularstorm.The stormthat producesextremewater levelsin one part of Lake Erie might not, and probablydoes not, produceextremelevelsin other parts.Thereforethe numberof calibrationand validationstormsselected,to assessmodelpredictionaccuracy,coveredall partsof the lake shoreline.
Calibrationand verificationof the coupled Delft3D-FLOWand Delft3D-WAVEmodels is performedby a time series comparisonof measuredand predicted/modeledstorm surge values at different water level recordingstations on Lake Erie. A similar time series comparisonis also performedfor wave heights.
The Delft3D models are calibratedusing extreme historicwind and pressuredata from multiplemeteorological   and water levelrecordingstations.Calibrationand verificationof the coupled Delft3D-FLOWand Delft3D-WAVEmodels demonstratesthat the hydrodynamic model is capableof computingthe stormsurge and seichedynamicsfor Lake Erie,as well as the significantwave heightsand periodsat PNPPfrom PMWS events.
PERRYNUCLEARPOWERPLANT                                                            Page 26 of 42

NTTFRecommendation       2.1 (HazardReevaluations):  Flooding                           Revision1 FirstEnergyCorporation                                                              March2,2016 PMSS The calibratedDelft3Dmodelis usedto determinethe PMSS.The historicwind and pressure field data is replacedwith candidatePMWS events,and the model is run to determinethe criticalPMWS.
JLD-ISG-2012-06     and ANSI/ANS2.8-1992requirethe antecedent(pre-storm)water level equalto the 1OO-year    maximumrecordedwater levelto be appliedas the initialstormsurge modelstillwater level.The 1OO-year   water levelof 575.8feet PerryLocalDatum(574.6feet IGLD 85) is used as the initialcondition/antecedent   water level in all the Delft3D-FLOW models.Sincethe probableminimumlow water levelat PNPP couldoccurat a time when the monthlymean lake level is at the long-termmean low probablelevel,the antecedent water level for low water evaluationis set to the long-termlow probablelevelat Lake Erie, which is equalto 569.2feet PerryLocalDatum(568feet IGLD 85).
Varioustopographicfeaturesaffectthe storm surge propagationtowardsPNPP.The site is locatedon the bluffsadjacentto the shoresof Lake Erie. The bluffsat the site are more than 40 feet abovethe 100-yearwater levelof the lake.
Maximum Historical and 2S-yearStorm Surge The historicalmaximumstorm surge is the largestof the determinedyearly maximumstorm surge heights.The historicalmaximumstorm surge height is used in combinedflooding scenariosas discussedin Section3.7.
Storm surgesare calculatedfrom monthlydata as the differencebetweenmonthlymaximum and monthly mean based on guidance providedby USACE. The Log PearsonType lll distributionis the commonlyacceptedfrequencyprocedurefor annualmaximumwaterlevels.
A frequencyanalysison the yearlymaximumstormsurge heightsobtainedfrom the Fairport and Eriestationsis performedusinga Log Pearsonlll statisticalanalysis.The 2S-yearstorm surge heightis used in combinedfloodingscenarios.
3.5.4. Results Simulationsof all the candidatePMWS eventsshowedthat the criticalPMWS event is the transpositionedSeptember1989wind stormevent maximizedover the PNPP site.This storm is the most intenseof all the PMWS eventswith a maximumwind speed of 106 miles/hour and is aligned along the north-southdirection.The maximum PMSS resultingfrom this PMWS event produceda maximumwater surfaceelevationof 582.8feet PerryLocal Datum, which is well below the site. Wave runup effects are evaluated with combined flooding scenariosas discussedin Section3.7.
Surge, Seiche, and Resonance Resultsshow that the levelof the rise due to a seicheis significantly lessthan the calculated surge height.For this reason,seichesare not the controllingflood eventat PNPP.
Resonancegeneratedby waves can cause problemsin enclosedwater bodies such as harborsand bays when the periodof oscillationof the water body is equal to the periodof the incomingwaves. However,the PNPP site is not located in an enclosedembayment.
Additionally,the periodof oscillationof Lake Erie near the PNPP site is determinedto be in the rangeof 11 to 15 hours.This is muchgreaterthan that of the peak spectralperiodof the incidentshallowwater storm waves. Consequently,resonanceis not a detrimentat PNPP duringthe criticalPMWS event.
PERRYNUCLEARPOWERPLANT                                                              Page 27 of 42

NTTF Recommendation     2.1 (HazardReevaluations): Flooding                        Revision1 FirstEnergyCorporation                                                         March2,2016 Probable Minimum Low Water Level resulting from the PMWS Simulationsof all the candidatePMWS stormeventsshow that the criticalPMWS eventthat would result in probable minimum low water level (drawdown)is the transpositioned November1998stormeventmaximizedoverthe PNPPsite.Thisstormhad the most intense southeasterlywinds of the examinedstorm events, with a maximum wind speed of 93 miles/hour.The probableminimum low water elevation(drawdown)associatedwith the transposedNovember1998 storm producesa probableminimumlow water level of 563.2 feet Perry Local Datum near the PNPP site. The invertsof the PNPP intake ports are at an averageelevationof 552.65feet PerryLocalDatum(USAR2.4.11.2.2.2).
3.6. Tsunami Assessment (ReferencePNPP 2015i)
NUREG/CR-6966identifiesthat earthquakes,landslides,and volcanoescan initiatetsunamis, with earthquakesbeing the most frequent cause. Dip-slip earthquakes(due to vertical movement)are more efficientat generatingtsunamis than strike-slipearthquakes(due to horizontalmovement).To generatea major tsunami,a substantialamount of slip and a large rupturearea is required.Consequently, only largeearthquakeswith magnitudesgreaterthan 6.5 generateobservabletsunamis.
3.6.1. Basis of Inputs
           . NationalCenterfor EarthquakeEngineeringResearch(NCEER)database
           . NaturalResourcesCanadaseismicitydata o   NOAA naturalhazardstsunamidatabase o   NOAA naturalhazardsvolcanodatabase o  Ohio Departmentof NaturalResources(ODNR)seismicitydata
           . USGSearthquakehazardsprogramdatabase 3.6.2. Gomputer SofhrvarePrograms
           . None 3.6.3. Methodology As identifiedby NUREGICR-7046,tsunami assessmentis referencedto NUREG/CR-6966 and NOAA TechnicalMemorandumOAR PMEL-136(ReferenceNOAA 2007).In addition, the more recently issued NRC guidance, JLD-ISG-2012-06,also addresses tsunami assessment.However,a screeningassessmentis appliedand JLD-lSG-2A12-06         provides guidanceon detailedtsunamimodelingthat is beyondthe scopeof a screeningassessment.
TechnicalMemorandumOAR PMEL-136reflectsa similartsunamiscreeningassessment describedby NUREG/CR-6966.
The NUREG/CR-6966      screeningassessmentis based on a regionalscreeningand a site screening.The regionalscreeningconsistsof researchinghistoricalrecordsfor tsunami recordsand the potentialfor tsunami-generatingsources.The site screeningevaluatesthe distancemeasuredalong site basedon the horizontaldistancefrom a coast,the longitudinal a river,and the gradeelevationin comparisonto the effectsof a tsunami.This assessment approachis based on a reviewof historicalrecordsand databases.
NUREG/CR-6966identifiesthat tsunamisare generatedby rapid,large-scaledisturbances of a body of water. The most frequent cause of tsunamis is an earthquake; however, landslidesand volcanoescan also initiatetsunamis.Becauseof the tsunami-generation sequenceassociatedwith earthquakes,dip-slipearthquakes(dueto verticalmovement)are more efficient at generatingtsunamis than strike-slipearthquakes(due to horizontal PERRYNUCLEARPOWERPLANT                                                         Page 28 of 42

NTTF Recommendation     2.1 (HazardReevaluations):   Flooding                        Revision1 FirstEnergyCorporation                                                            March2.2016 movement).Furthermore,to generatea major tsunami,a substantialamountof slip and a largerupturearea is required.Consequently,    only largeearthquakeswith magnitudesgreater than 6.5 generateobservabletsunamis.
As part of the assessment,the NOAA naturalhazardstsunamidatabaseis used to review historicaltsunamieventsand associatedrunupsfor the east coastof the UnitedStatesand Canada.Of the totalevents,therewere 7 tsunamieventsthat produced14 runupsoccurring in the Great Lakesregionfrom 1755to 1954.The USGS hazardfault databasefindingsare reviewedfor strongearthquakesor the verticaldisplacements    necessaryto inducea tsunami.
Additionally, the USGSearthquakehazardsprogram,the NCEERdatabase,and the Natural ResourcesCanadadatabaseare reviewedfor historicalearthquakesin the region.
ODNR data is also reviewed for earthquake-generated         tsunami and landslide-induced tsunami. Lastly, the NOAA natural hazards volcano database is reviewed to assess volcanoesin the Lake Erie region.
3.6.4. Results Accordingto ODNR, an earthquake-generated        tsunami in Lake Erie would requirea very large earthquake on the order of magnitude 7 .0 or greater and significantvertical displacement.Historically,in the Lake Erie region, the largest earthquakesare in the magnitude5.0 range. Preliminaryanalysisof post-glacialsedimentsin the region has not yielded evidence of a large earthquakein the last few thousand years. Furthermore, earthquakesin the region,for which sufficientdata are available,show primarilyhorizontal ratherthan verticalmovement,which is not as conduciveto tsunamigeneration.
Tsunamiscan also be generatedby the downslopemovementof a very largevolumeof rock or sediment,eitherfrom a rockfallabovethe water or from a submarinelandslide.Although large amounts of unconsolidatedsedimentsare washed into Lake Erie each year when shorelinebluffs are undercutby wave action,these masses lack sufficientvolume and rapid collapseto displacea volumeof waterthatwouldcreatea tsunami.Lake Eriealso has a very gentlebottomprofile,particularlyin the westernand centralbasins.The easternbasin has steeper slopes, but not steep enough for a large amount of sedimentto suddenlyflow downslopein a submarinelandslide.
The NOAA naturalhazardstsunamidatabaseidentifiesonly two occurrencesof non-seiche (or non-wind-induced)  tsunami events in the Great Lakes region. The two occurrences yieldedslightor smallwave effects.
The USGS EarthquakeHazards Programfault databasecontainsno known Quaternary faults (or currentfaults) in this region becausegeologistshave not found any faults at the Earth's surface.Consequently,no potentialexists for strong earthquakesor the vertical displacementnecessaryto inducea tsunami.Variousearthquakedatabases,includingthe USGS Earthquake Hazards Program earthquake database, the National Center for EarthquakeEngineeringresearchcatalog,and NaturalResourcesCanada,identifythat the largesteventsin the vicinityare no greaterthan magnitude5.0.
Lastly,no volcanoesare locatedin the Lake Erie             accordingto the NOAA natural hazardsvolcanodatabase.
Tsunamiis not the controllingfloodeventat PNPP.
3.7. Gombined Effect Flood (including Wind-GeneratedWaves) (ReferencePNPP2015m)
Evaluationof floodscausedby precipitation    eventsis coveredin AppendixH.1 of NUREG/CR-7046.Thethreealternativesare addressedin floodingon streamsand rivers(Section3.1),which PERRYNUCLEARPOWERPLANT                                                            Page 29 of 42

NTTF Recommendation      2.1 (HazardReevaluations): Flooding                        Revision1 FirstEnergyCorporation                                                         M a r c h2 , 2 0 1 6 identifiesthe resulting water surface elevations.Combined effect flooding evaluates the componentof addedwaves inducedby 2-yearwind speedalongthe criticaldirection.
Evafuationof floodsalongthe shoresof enclosedbodiesof water is coveredin AppendixH.4.1 of NUREG/CR-7046      and includesone alternative:
Gombination of:
       -     Probablemaximumsurgeand seichewith wind-waveactivity.
       -     The lesser of the 100-yearor the maximum controlledwater level      the enclosed body of water.
Three alternativesare specifiedin Appendix H.4.2 of NUREG/CR-7046for streamside locations of enclosed bodies of water. Each of the alternativesconsideredhas three componentscontributing   to the water surfaceelevation.
Alternative 1 - Combination of:
The lesserof one-halfof the PMF or the 500-yearflood; Surge and seiche from the worst regionalhurricaneor windstormwith wind-wave activity;and The lesser of the 1O0-yearor the maximumcontrolledwater level in the enclosed body of water.
Afternatitve2 - Combination of:
PMF in the stream; A 25-yearsurgeand seichewith wind-waveactivity;and The lesserof the 1OO-year  or the maximumcontrolledwater level in the enclosed body of water.
          . Alternative3-Gombinationof:
          -    A 25-yearflood in the stream;
          -    Probablemaximumsurgeand seichewith wind-waveactivity;and
          -    The lesserof the 100-yearor the maximumcontrolledwater level in the enclosed body of water.
3.7.1. Basis of lnputs Inputsincludethe following:
          . PMSSfrom Calculation    50:47.000
          . Wave parametersfor Lake Erie at PNPPfrom Calculation50:47.000 o    10O-yearor maximumcontrolledwater levelin Lake Eriefrom Calculation50:46.000
          . Lake Erie historicalmaximumsurgefrom Calculation50:46.000
          . Lake Erie 2S-yearsurgefrom Calculation50:46.000
          . 2-yearwind speed
          . Site topography 3.7.2. Computer Software Programs
          . ArcGlSDesktop10.1 o    HEC-GeoRAS10.1
          . HEC-RAS4.1
           . MicrosoftExcel PERRYNUCLEARPOWERPLANT                                                          Page 30 of 42

NTTF Recommendation     2.1 (HazardReevaluations): Flooding                           Revision1 FirstEnergyCorporation                                                           March2,2016 3.7.3. Methodology Each combinationincludescoincidentwind-waveactivity. Coincidentwind-waveactivityis determinedfor the critical flooding combinationusing the USACE guidance outlined in USACE CoastalEngineeringManual (ReferenceUSACE 2008).Wind setup is the effect of horizontalstress on the water surface.Runup is the maximumelevationof wave uprush abovestillwaterlevel.
3.7.3.1. H.4.1Gombination Probablemaximum surge and seiche is discussedin Section 3.5. Wind wave activity includeswave height,wind setup,and wave runup.Wave heightand wlnd setupare included as part of the PMSS developed using Delft3D model. Wave runup is determinedin accordancewith USACEguidanceon the shorelineand bluffslopesadjacentto Lake Erie.
3.7,3.2. H.4.2GombinationAlternatives As a boundingapproach,the maximum Lake Erie water level from all three alternatives, includingthe initialwater level and surge effects,is used as the downstreamboundary conditionfor MajorStreamand MinorStreamflooding,and combinedwith the PMF for each stream.lt is determinedthat the maximumLake Eriewater levelhas no significanteffecton the PMF analyses.Based on the analysesand resultsfor the Major Stream and Minor Stream,the DiversionStreamwas not specifically  analyzedfor combinedeffectflooding.The DiversionStream is not adjacentto the power block. Therefore,wind wave activity has no specificconsequence.
3.7.4. Results The H.4.1Combinationmaximumwater surfaceelevationis 582.8feet Perry Local Datum, includingwind setup,and occurswest of the power block along the shorelinebluff slopes.
The maximumeffects due to wind wave activityoccur at a locationjust east of the power blockalonga sectionof shorelinewith steeperbluffslopes.Wave actionanalysisconcludes that a maximumwave runupol27 .5 feet may be generatedon the shorelinebluffslopes.The PMSSmaximumwatersurfaceelevationat this locationis 581.9 feet PerryLocalDatum.The maximumwave runup elevationduring the controllingPMSS is equal to 609.5 feet Perry LocalDatum,which is well belowthe site.
The maximumcombinedwatersurfaceelevationfor the MajorStreamand the MinorStream are the PMF results.
The Major Stream and DiversionStream are not directly adjacentto PNPP safety-related structures.Therefore,wind wave activity has no specificconsequence.The Minor Stream PMF floodingis maintainedwithinthe streambanks,eliminatingthe potentialfor wind wave effectsat the power block.
3.8. Local Intense Precipitation(ReferencePNPP 2015c,PNPP 2016a,and PNPP 2016c)
The LIP is an extremeprecipitation eventat a given location.The LIP evaluationis performed in accordancewith NUREG/CR-7046. Cool-seasonalternativesare determinedto be bounded by the all-seasonalternative.
3.8.1. Basis of Inputs
: sii:  :Hfi';#l;:n:r*r"::         ?il?rt:tix','iin.;:
PERRYNUCLEARPOWERPLANT                                                            Page 31 of 42

NTTF Recommendation     2.1 (HazardReevaluations):   Flooding                         Revision1 FirstEnergyCorporation                                                             March2,2016 o  Site underdrainsystemdrawings
               . Manning'sroughnesscoefficients o  MajorStreammaximumwater surfaceelevationresults 3.8.2. Computer Software Programs
             . ArcGlSDesktop10.1
             . FLO-2DPro, Build 14-08-09(incorporating   SWMM 5.0.022)
             . HEC-RAS4.1
             . MATLAB8.6.0.267246 o   MicrosoftExcel 2013 3.8.3. Methodology The effects of LIP are analyzedusing FLO-2D software.The softwareuses shallowwater equationsto routestormwaterthroughoutthe site. FLO-2Ddepictssite topographyusinga digitalelevationmodel(DEM)capturingall terrainfeatures,such as grading,slopes,drainage divides,and low areasof the site.
The MajorStreamis incorporatedintothe modelas a staticwater level boundarycondition.
The grid model DEM is developedfrom ground surface informationcombinedwith the maximumwatersurfaceelevationsdeterminedfor the MajorStreamas a boundarycondition.
The entire drainagearea of the Minor Stream is incorporatedinto the model domain.The MinorStreameightfoot diameterculvertdischargingto LakeErieis includedin the modeling.
The culvert feature is modeled using the SWMM software incorporatedinto the FLO-2D software.HEC-RAS software is used to derive a stage-dischargerelationshipassignedto the culvert.The DiversionStream and associatedwatersheddo not affect the area of the power blockanalyzedfor the effectsof LlP. The DiversionStreamand associatedwatershed alsodo not affectthe MajorStreamor the MinorStream.The DiversionStreamis not included in the FLO-2Dmodeling.
Manning'sroughnesscoefficientvalues are selectedbased on land cover type using the guidance provided in the FLO-2D manual. Two types of obstructionsare modeled:
buildings/structuresthat completelyblockthe water passage,and securitywall barriersthat could be overtoppedif the waterdepth increasesabovethe top of the wall.The leveefunction within FLO-2Dis used to incorporatesite securityfeatures,which could impactthe natural drainagecharacteristics   of the site.
The site storm drainagenetwork is incorporatedinto the model using the S\A/MMsoftware incorporatedinto the FLO-2D software. All inlets are modeled with a 50 percent area reductionand 25 percentperimeterreductionto accountfor inletgratingand potentialdebris accumulation.The pipe networkwas also modeledusing a 10 percentreductionof pipe capacity.In addition,securityrestrictionsaffectingpipe capacityare also incorporated.
The elementsof the roof drain systemthat connectdirectlyto the storm drainagenetworkor groundwaterare incorporatedinto the model. Roof drains that dischargedirectlyto the ground are not modeled.The roof drain system is incorporatedinto the modelingwithout reductions.Roof elevationsare modeledas describedby site drawings.Roof parapetsare modeledusingthe levee function.Roof scuppersare incorporatedinto the parapetlevees.
The site also includesan underdrainsystem that is independentof the storm drainage network.Sixteenunderdrainmanholelocationsare modeledas open inlets.Inletreductions are incorporatedfor the physicalinlet grating. However,due to the large three feet to four feet diameterunderdrainpipe sizes,no reductionof pipe capacityis included.
PERRYNUCLEARPOWERPLANT                                                             Page 32 of 42

NTTF Recommendation      2.1 (HazardReevaluations):   Flooding                        Revision1 FirstEnergyCorporation                                                            March2,2016 The site-specific rainfallis appliedas a 6-hourstormeventbasedon 5-minuteincrementsto capturethe highestintensityof the distribution.Front,one-third,center,two-thirds,and end-loading temporal distributionsare consideredin the evaluation.No rainfall losses are includedin the modeling.
3.8.4. Results The site-specificbeyonddesignbasis rainfallwith an end loadingdistributionproducesthe criticalresultsfor the effectsof LIP flooding.The maximumwater surfaceelevationsat the power block rangefrom 619.9feet Perry Local Datumto 621.3feet Perry Local Datum.ln general,the southend of the powerblockaroundthe Unit2 TurbineBuildingresultsin higher maximumwatersurfaceelevations.The resultingmaximumwatersurfaceelevationsexceed 57 door thresholdelevationsof the powerblock.The maximumwater depthsat the 57 door locationsrangefrom 0.1 feet to 1.0 feet above the door thresholdelevationsfor durations rangingfrom 0.1 hoursto 6 hours.
Maximum water surface elevations north of the power block at the Service Water PumphouseBuildingand the EmergencyServiceWater PumphouseBuildingrange from 619.3feet PerryLocalDatumto 620.5feet PerryLocalDatum.The resultingmaximumwater surface elevationsexceed one door thresholdelevationat the ServiceWater Pumphouse.
The maximumwater depth is 0.1 feet above the door thresholdelevationfor a durationof 0.1 hours.The resultingmaximumwater surfaceelevationsexceedthe two door thresholds and one louveropeningof the EmergencyServiceWater Pumphouse.The maximumwater depths range from 0.7 feet to 1.0 feet above the openingelevationsfor durationsranging from 5.8 hoursto 6 hours.
The resultingmaximumwater surface elevationsexceed two door thresholdelevationsat the Unit2 CirculatingWaterPumphouse.The maximumwaterdepthsare 0.5 feet abovethe door threshold elevationsfor durations of 0.7 hours. The Unit 2 CirculatingWater Pumphouseis an abandonedunit that does not communicate,in terms of flooding,with SSCs requiredfor safe plant operationor shutdown.Therefore,floodingof this buildingis inconsequential  to plantsafety.
4.0 COMPARISONOF BEYONDDESIGNBASISWITH UPDATEDDESIGNBASIS The reevaluatedmaximumwater surfaceelevationsdue to the LlP, storm surge (PMSS),and combinedeffectfloodfor stormsurgeincludingwind-generated      wavesexceedthe designbasis.
For LIP flooding,the designbasisand beyonddesignbasisevaluationsare identicalexceptfor the rainfallinput.The design basis rainfallinput is the CorrectedPMP front loadedtemporal distribution.The beyonddesignbasis rainfallinput is the site-specificPMP and is evaluatedfor the front,one-third,center,two-thirds,and end-loadingtemporaldistributions.
The design basis LIP analysisresultsexceed26 door thresholdelevationsof the power block and the two door thresholdsand one louver opening of the Emergency Service Water Pumphouse.Door thresholdelevationsat the Service Water PumphouseBuildingand the CirculatingWater Pumphousesare not exceeded.The beyonddesignbasis LIP resultsexceed 57 door thresholdelevationsof the power block, one door of the ServiceWater Pumphouse Building,the two door thresholdsand one louver opening of the EmergencyService Water Pumphouse,and two doors of the Unit 2 CirculatingWater Pumphouse.The design basis maximumwater surfaceelevationsat the power block rangefrom 619.8 feet Perry Local Datum to 620.7feet Perry Local Datum.The beyonddesign basis maximumwater surfaceelevationsat the power block exceedthe design basis range by 0.1 feet to 0.6 feet.
PERRYNUCLEARPOWERPLANT                                                            Page 33 of 42

NTTF Recommendation     2.1 (HazardReevaluations):    Flooding                    Revision1 FirstEnergyCorporation                                                         March2,2016 For the lakestormsurgeflooding,the designbasisassumesthe surgeacts only in one direction.
A site-specificwind and pressurefield is developedas part of the reevaluation.More recent stormsprovidethe controllingwind for reevaluatedsurgefloodingat PNPP.
As previouslyindicated,the PMSS maximumstillwatersurfaceelevationexceedsthe design basiselevationof 580.5feet Perry Local Datumby a maximumvalue of 2.3 feet. The UHS for PNPP is Lake Erie. Although the design basis is exceeded,the PMSS Stillwatersurface elevationremainsbelowthe safety-related     pumpsand equipmentlocatedaboveelevation586.5 feet Perry Local Datum in the emergencyservicewater pumphouse.Additionally,the PMSS minimumstillwatersurfaceelevationis lowerthan the designbasis of 565.26feet Perry Local Datumby 2.0 feet. However,previousevaluationdeterminedthat thereis adequatenet positive suctionhead and submergenceof the emergencyservicewater pumpsfor a resultingelevation as low as 559.0feet Perry Local Datum (ReferencePNPP 2004).
For the combinedeffect flood from storm surge includingwind-generatedwaves, the design basisincorporatedthe guidanceoutlinedby the USACEShoreProtection,Planningand Design, TechnicalReportNo. 4 (ReferenceUSACE 1966).The beyonddesign basis coincidentwind-wave activityis determinedusing the current USACE guidanceoutlinedin USACE Coastal Engineering Manual.
The maximumsurgerunupexceedsthe designbasiselevationof 607.9feet PerryLocalDatum by a maximum value of 1.6 feet. However,the maximum effects of the PMSS event are maintainedon the bluffsadjacentto LakeErie.The sitegraderemainshigherthan the maximum effectsof the PMSS event. The wave runup would cause the lake level to increaseas well as decreasethroughthe cyclingof the waves. The long intaketunnel of the plant dampensthe impactof the high and low wave action.The waterlevelswithinthe pumphousetend to equalize to the sustainedaverageheightof the lake.Therefore,the resultingbeyonddesignbasisPMSS effects are inconsequentiaI to safety-related structures.
The comparisonsof existingand reevaluatedflood hazardsare providedin Table5.
PERRYNUCLEARPOWERPLANT                                                         Page 34 of 42

NTTFRecommendation     2.1 (HazardReevaluations):    Flooding                       Revision1 FirstEnergyCorporation                                                           March2,2016 Table 5 - Comparison of Existing and ReevaluatedFlood Hazardsat PNPP Flood-Gausing Flood Hazard Reevaluation Mechanism        Design Basis             Gomparison Results Floodingin       MaiorStream(t)             Bounded       MaiorStream streamsand       (ReferencePNPP                           (Reference  PNPP2015p) rivers           2015p)                                   All-Season  PMFElevation is 628.5 PMF Elevationis                          feetPerryLocalDatum(at railline 628.5 feet Perry                          bridge).
LocalDatum(at railline bridge).
PMF Flow is                              All-SeasonPMF Flow is 34,200cfs.
34,200cfs.
Cool-season                              Cool-Seasonboundedby all-boundedby all-                           season.
season.
MinorStream(a)                            MinorStream (ReferencePNPP                            (ReferencePNPP2015b) 201sb)                                   All-SeasonPMF Elevationis 619.7 PMF Elevationis                          feet Perry Local Datum.
619.7feet Perry LocalDatum.
P M F F l o wi s 1 , 1 0 0               All-SeasonPMF Flowis 1,100cfs.
cfs.
Cool-season                               Cool-Seasonboundedby all-boundedby all-                           season.
season.
DiversionStream(a)                        DiversionStream (ReferencePNPP                            (ReferencePNPP2015b) 2015b)                                    PMF Elevationis 629.2feet Perry PMF Elevationis                           LocalDatum.
629.2 feet Perry LocalDatum.
PMF Flowis 4,200                          PMF Flowis 4,200cfs.
cfs.
Cool-season                               Cool-seasonboundedby all-boundedby all-                            season.
season.
PERRYNUCLEARPOWERPLANT                                                           Page 35 of 42

NTTF Recommendation   2,1 (HazardReevaluations):Flooding                             Revision1 FirstEnergyCorporation                                                            March2,2016 Table 5 - Gomparisonof Existing and ReevaluatedFlood Hazardsat PNPP (Continued)
Flood-Causing Flood Hazard Reevaluation Mechanism    Design Basis          Comparison Results Dam breaches    No upstream           Bounded         Dam assessmentindicatesno and failures    impoundments.                        watersheddams.
Stormsurge      Watersurface          Notbounded. Watersurfaceelevationis 582.8 elevation  is 580.5 Exceedscurrent feetPerryLocalDatum(Reference feetPerryLocal        designbasis. P N P P2 0 1 5 h ) .
Datum(USAR, Section   2.4.5.2.2).
Lowwater                              Lowwaterelevationis 563.2feet elevation  is 565.26                  PerryLocalDatum(Reference feetPerryLocal                        PNPP201sh).
Datum(USAR, Section   2.4.11.6).
Seiche          Thisflood-causing Bounded             Boundedby storm surge (Reference mechanismis not                       PNPP20159).
described specificallyfor the site in the USAR (USAR,Section 2.4.6).
Tsunami         This flood-causing Bounded            Tsunamiassessment         indicates a mechanismis                           slightpossibility   of tsunamis in the identlfiedas not                      GreatLakesregion.However,the applicablein the                      seismicity in the regionsuggestsno USAR (USAR,                           potentialexistsfor strong Section2.4.6).                        earthquakes   or the vertical displacement    necessary   to inducea substantial tsunami(Reference PNPP2015i).
lce-induced     This flood-causing Bounded            lce-inducedfloodingis boundedby flooding        mechanismis                           the all-seasonPMF event identifiedas not                      (ReferencePNPP 2015e).
plausiblein the USAR (USAR, Section2.4.7).
Channel         This flood-causing Bounded            Channeldiversionis not migrationor     mechanismis                           characteristicfor adjacentstreams diversion       identifiedas not                      (ReferencePNPP2015e).
applicablein the USAR (USAR, Section2.4.$.
PERRYNUCLEARPOWERPLANT                                                            Page 36 of 42

NTTF Recommendation       2.1 (HazardReevaluations):  Flooding                          Revision1 FirstEnergyCorporation                                                             M a r c h2 , 2 0 1 6 Table 5 - Comparison of Existing and ReevaluatedFlood Hazardsat PNPP (Continued)
Flood-Gausing                                             Ffood Hazard Reevaluation Mechanism        Design Basis         Comparison        Results Combinedeffect      Wave runupon         Notbounded.       Waverunupon LakeErieshoreline flood(including     LakeErieshoreline Exceedscurrent       bluffsis 609.5feet PerryLocal wind-generated      bluffsis 607.9       designbasis.      Datum(Reference    PNPP2015h).
waves)              PerryLocal Datum (USAR,Section 2.4.2.2).                              Windwaveeffectson streamsare notapplicable.
                     \Mnd wave effects on streamsare not applicable.
LIP                 Maximumwater         Notbounded. Maximumwater surfaceelevations surfaceelevations Exceedscurrent at the powerblock rangefrom 619.9 at the powerblock designbasis.         feet PerryLocal Datumto 621.3feet rangefrom 619.8                        Perry Local Datum.(c) feet Perry Local                       (ReferencePNPP 2016c)
Datumto 620.7 feet Perry Local pq{urn.(axo)
(ReferencePNPP 2016b)
(a)Valuesare basedon the reconstituteddesignbasisvaluesdiscussedin Section2.3.
(b)Thedoorschedulefor the designbasisLIPfloodhazardresultsare providedin Attachment   1.
(c)Thedoorschedulefor the beyonddesignbasisLIPfloodhazardresultsare providedin Attachment       2.
5.0 INTERIMAND PLANNEDFUTUREACTIONS The FfoodingHazardReevaluationReportevaluatedthe applicablefloodinghazardsfor PNPP.
Three of the postulatedreevaluatedflood hazardevents (lake flooding,combinedeffects,and LIP) resultedin maximumflood water elevationshigherthan previouslycalculatedfor PNPP.
These postulatedflooding events are consideredbeyond design basis events and do not constitutean operabilityconcern.The PMSS event and the combinedeffectsfor wave runupon the Lake Erie shorelineresultsare inconsequential. Therefore,no interimor futureactionsare plannedfor this event.
The interimactionplan is to continuewith actionsassociatedwith ConditionReportCR 2015-08036 until all design basis modificationsbased on Calculation50:64.000LIP results are complete.Design basis modificationswill be implementedfor the storm sewer system,the underdrainsystem,and door specificprotectionor analysis.lmplementation   of the modifications for the storm sewer system and the underdrainsystem,as incorporatedinto the design basis LIP Calculation50:64.000,are requiredfor the beyonddesignbasis LIP Calculation50:66.000 to be valid.Door protectionwill be developedfor the beyonddesignbasisCalculation50:66.000 LIP resultsthrougheither analysisor physicalbarriers.Analysiswill determinethe volumeof inflowthroughthe doors for the durationof flooding.The inflowvolume will be comparedto internalfloodinganalysesto determineif externalfloodingis boundedor not. Physicalbarriers will be determinedas eitherpermanentbarriersor throughprocedure.
PERRYNUCLEARPOWERPLANT                                                             Page37 ot 42

NTTF Recommendation  2.1 (HazardReevaluations):Flooding                        Revision1 FirstEnergyCorporation                                                     March2.2016 6.0 ACRONYMS ANS                AmericanNuclearSociety ANSI               AmericanNationalStandardsInstitute ArcMap             Arc Map Software ArcGlS             Arc GeographicInformationSystemSoftware AutoCAD            AutomatedComputerAided DesignSoftware CFR               Code of FederalRegulations cfs               CubicFeet per Second CR                ConditionReport Delft3D           Delft3-Dimensional Software Delft3D-FLOW      Flow Moduleof Deft3DSoftware Delft3D-WAVE      Wave Moduleof Deft3DSoftware Delft3D-RGFGRID Grid GenerationModuleof Delft3DSoftware Delft3D-QUICKIN Modification/generation Moduleof Delft3DSoftware DEM               DigitalElevationModel DTM               DigitalTerrainModel ECP               Engineering ChangePackage ESP               EarlySite Permits FENOC             FirstEnergyNuclearOperatingCompany FLO.2D            FLO 2-Dimensional  Software GIS               GeographicInformationSystem HEC-GeoRAS        HydrologicEngineeringCenter GeographicRiver Analysis System software HEC.HMS           HydrologicEngineeringCenterHydraulicModelingSystemsoftware HEC.RAS           HydrologicEngineeringCenterRiverAnalysisSystemsoftware IGLD85                        Great LakesDatumof 1985 International JLD.ISG           Japan Lessons-LearnedProjectDirectorateInterimStaff Guidance LIP               LocalIntensePrecipitation MATLAB            MatrixLaboratorySoftware NAVD 88           NorthAmericanVerticalDatumof 1988 NCEER             NationalCenterfor EarthquakeEngineeringResearch NGVD 29.          NationalGeodeticVerticalDatumof 1929 NID               Nationallnventoryof Dams NOAA              NationalOceanicand AtmosphericAdministration NRC               NuclearRegulatoryCommission PERRYNUCLEARPOWERPLANT                                                      Page 38 of 42

NTTF Recommendation   2.1 (HazardReevaluations):Flooding                      Revision1 FirstEnergyCorporation                                                    March2,2016 NRCS                NationalResourcesConservationService NTTF                NearTerm Task Force NUREG               US NuclearRegulatoryCommissionRegulation NUREG/CR            US NuclearRegulatoryCommissionRegulationContractorsReport NWS                 NationalWeatherService OAR PMEL            Oceanic and AtmosphericResearch Pacific Marine Environmental Laboratory ODNR                Ohio Departmentof NaturalResources PFA                 PromptFunctionalityAssessment PMF                 ProbableMaximumFlood PMP                 ProbableMaximumPrecipitation PMS                 ProbableMaximumStorm PMSS                ProbableMaximumStormSurge PMWS                ProbableMaximumWindstorm PNPP                PerryNuclearPowerStation RG                  RegulatoryGuide SSCs                Structure,Systems,and Components SWMM                Storm Water ManagementModel software UHS                 UltimateHeatSink USACE               U.S.Army Corpsof Engineers USAR                UpdatedSafetyAnalysisReport USBR                U.S. Bureauof Reclamation USGS                U.S. GeologicalSurvey 7.0 REFERENGES (ANSI N170-1976) American National Standard, Standardsfor Determining Design Basrs Flooding at Power Reactor Sifes, Prepared by the American Nuclear Society Standards CommitteeWorkingGroupANS-2.8,1976.
(ANSI/ANS-2.8-1992)ANS, American NationalStandardfor DeterminingDesign Basis Flooding at Power Reactor Sifes, Prepared by the American Nuclear Society Standards Committee WorkingGroupANS-2.8,1992.
(JLD-ISG-2013-01) NRC, Guidancefor Assessmentof FloodingHazardsdue to Dam Failure, Revision0, July 2013.
(JLD-ISG-2012-06) NRC,Guidancefor Performinga Tsunami,Surgeor SeicheFloodingHazard Assessment,Revision0, January2013.
(NEl August 2012) NEl, Report 12-08,Overviewof ExternalFloodingReevaluations, August 2012.
PERRYNUCLEARPOWERPLANT                                                    Page 39 of 42

NTTF Recommendation     2.1 (HazardReevaluations):  Ffooding                           Revision1 FirstEnergyCorporation                                                            March2,2016 (NOAA 1956)U.S. WeatherBureau,U.S. Departmentof Commerce,SeasonalVariationof the Probable Maximum Precipitation East of the 105thMeridian for Areas from 10 to 1000 Square Miles and Durationsof 6, 12, 24, and 48 Hours, HydrometeorologicalReportNo. 33, Silver Spring Maryland,1956.
(NOAA1978)NationalWeatherService,NationalOceanicand AtmosphericAdministration,             U.S.
Departmentof Commerce,ProbableMaximumPrecipitationEstimafes,United SfafesEasf of the 105thMeridian,HydrometeorologicalReportNo. 51,SilverSpring Maryland,1978.
(NOAA 1982)NationalWeatherService,NationalOceanicand AtmosphericAdministration,            U.S.
Department of Commerce, Application of Probable Maximum Precipitation Estimates,United Sfafes Easf of the 105thMeridian, HydrometeorologicalReport No. 52, Silver Spring Maryland, 1982.
(NOAA 2OO7)NationalOceanicand AtmosphericAdministration,         TechnicalMemorandumOAR PMEL-136,Scientificand Technical/ssues in TsunamiHazard Assessmentof Nuclear Power Plants,May 2007.
(NRC March2012)NRC, LettertoLicensees,RequestforInformationPursuanttoTitle 10 of the Codeof FederalRegulations    50.54(f)RegardingRecommendations     2.1,2.3, and 9.3 of the Near-Term Task ForceReviewof Insightsfrom the FukushimaDai-ichiAccident,March 12,2012.
(NRC May 2012) NRC, Letterto Licensees,Prioritizationof ResponseDue Dates for Request for InformationPursuantto Title 10 of the Code of Federal Regulations50.54(f)Regarding FloodingHazardReevaluations      for Recommendation  2.1 of the Near-TermTask ForceReview of lnsightsfrom the FukushimaDai-ichiAccident,May 11, 2012.
(NUREG-0800)NRC, NUREG-0800,StandardReview PIan for the Review of Safety Analysis Repods for Nuclear Power Plants: LWR Edition - Stfe Characterisfibs and Site Parameters (Chapter2), ML070400364,March2007.
(NUREG/CR-7046)NRC, NUREGICR-7046,PNNL-20091, Design-BasisFlood Estimationfor Site Characterizationat Nuclear Power Plantsin the United Sfafes of America, ML113214195, November2011.
(NUREG/CR-6966)NRC, NUREG/CR-6966,TsunamiHazard Assessmentat Nuclear Power Plant Sdesin the UnitedSfafesof America,NationalTechnicalInformationService,March2009.
(ODNR 2006) Ohio Departmentof NaturalResources,Divisionof GeologicSurvey, Surficial Geologyof the Cleveland North30 X 60 Minute Quadrangle,March 2006.
(ODNR 2013) Ohio Departmentof Natural Resources,ProbableMaximumPrecipitationStudy for the Sfafe of Ohio, preparedby AppliedWeatherAssociates,LLC, February2013.
(PNPP2004)FENOCCalculationP45-081, Evaluationof Net PositiveSuctionHead (NPSH)and SubmergenceRequiremenfsfor the Emergency ServiceWater (ESW Sysfem Pumps, Revision 0.
(PNPP 2015a)FENOC Calculation50:32.000,PNPP StreamModificationPMP, Revision0.
(PNPP2015b)FENOCCalculation50:33.000,PNPP StreamModificationPMF, Revision0.
(PNPP2015c)FENOCCalculation50:36.000,PNPPSife-SpecificAll-SeasonPMP, Revision0.
(PNPP2015d)FENOCCalculation50:43.000,PNPP DamsAssessmenf,Revision0.
(PNPP2015e)FENOCCalculation50:44.000,PNPPlce Jam and ChannelMigration Assessmenf,Revision0.
(PNPP2015f)FENOCCalculation50:45.000,PNPPWind Climatology,Revision0.
PERRYNUCLEARPOWERPLANT                                                             Page40 of 42

NTTF Recommendation    2.1 (HazardReevaluations):  Flooding                      Revision1 FirstEnergyCorporation                                                        March2,2016 (PNPP20159)FENOCCalculation50:46.000,PNPPSurgeand SeicheScreening,Revision0.
(PNPP2015h)FENOCCalculation50:47.000,PNPPSu4geand SeicheAnalysis,Revision0.
(PNPP2015i)FENOCCalculation        50:48.000,PNPPTsunamiAssessment,   Revision0.
(PNPP2015j)FENOCCalculation50:52.000,PNPPRainfallRunoff GISAnalysis,Revision0.
(PNPP2015k)FENOCCalculation50:53.000,PNPPSurgeand SeicheG/S Analysis,Revision 0.
(PNPP20151)FENOCCalculation50:54.000,PNPPSu4geand SeicheCalibration,Revision0.
(PNPP2015m)FENOCCalculation         50:55.000,PNPPCombinedEvents,Revision0.
(PNPP2015n)FENOCCalculation50:58.000,PNPPStreamModification         BermFailureAnalysis, Revision0.
(PNPP 2015o) FENOC Calculation50:59.000, PNPP Site-SpecificAII-SeasonSub-Hour Probable Maximum PrecipitationAnalysisfor 1-10 Square Miles, Revision0.
(PNPP 2015p) FENOC Calculation50:62.000, PNPP Major Stream Rail ModificationPMF, Revision0.
(PNPP 2015q) FENOC Calculation50:63.000, PNPP Major StreamAccess Road Modification Probable Maximum Flood, Revision0.
(PNPP2016a)FENOCCalculation50:31.000,PNPP GISAnalysisforEffecfsof L/P, Revision0 (PNPP2016b)FENOCCalculation50:64.000,PNPP SiteModificationsLocallntense Precipitation,Revision0.
(PNPP 2016c) FENOC Calculation50:66.000, PNPP Site ModificationsBeyond Design Basis Local lntensePrecipitation,Revision0.
(PNPP CN-1.1)CN-1.1 Posf Foundations,Sife Roads, and Catch             Revision0, Postlt NoteP-01.
(PNPPCN-1.1.1)CN-1.1.1 StormDrainage/ Catch BasinSysfem,                 Post lt Note P-01.
(PNPP CR 2015-05079)Condition Report 2015-05079,External Flooding during a Probable Maximum Flooding Event (West Srde of Plant).
(PNPP ECP 13-0802)EngineeringChange Package 13-0802,Minor Stream Modification, Revision0.
(PNPP CR 2015-08036)ConditionReporl2015-08036,PFA neededfor sitefloodingr'ssues.
(USACE 1966) U.S. Army Corps of Engineers,Coastal EngineeringResearchCenter, Shore Protection,Planningand Design,TechnicalReportNo. 4, Washington,D.C., 1966.
(USACE2008) U.S. Army Corps of Engineers,CoastalEngineeringManual,EM 1110-2-1100, August2008.
(USAR)PerryNuclearPowerPlant,UpdatedSafetyAnalysisReport,Revision17.
(USBR 1973) U.S. Departmentof the Interior,U.S. Bureau of Reclamation,Design of Small Dams,A Water ResourcesTechnicalPublication,SecondEdition,1973.
(USGS1943)U.S.Department      of the Interior,           Survey,PerryQuadrangle, U.S.Geological Perry,Ohio1905,Reprinted    1943.
PERRYNUCLEARPOWERPLANT                                                        Page41 of 42

NTTF Recommendation   2.1 (HazardReevaluations):Flooding                       Revision1 FirstEnergyCorporation                                                     March2,2016 (USGS 1992)U.S. Departmentof the Interior,U.S.GeologicalSurvey,Perry Quadrangle,Ohio-Lake Co., 7.S-MinuteSen'es,Perry,Ohio 1960, Revised1992.
(USGS 1994)U.S. Departmentof the Interior,U.S. GeologicalSurvey,Perry Quadrangle,Ohio-Lake Co., 7.S-MinuteSen'es,Perry,Ohio 1994.
(USGS2010)U.S. Departmentof the Interior,U.S.GeologicalSurvey,Perry Quadrangle,Ohio, 7.S-MinufeSen'es,Perry,OH 2010.
PERRYNUCLEARPOWERPLANT                                                      Page 42 of 42

NTTFRecommendation   2.1 (HazardReevaluations):
Flooding                Revision1 FirstEnergyCorporation                                                  2.zArc March ATTACHMENT       1 Updated Design Basis LIP Flood Hazard Results Front Temporal Distribution (ReferencePNPP2016b)
PERRYNUCLEARPOWERPLANT                                               Page 1 of 8

NTTF Recommendation        2.1 (HazardReevaluations):Flooding                                Revision1 FirstEnergyCorporation                                                                  March2.2416 Updated Design Basis LIP Flood Hazard Results at Door Locations for Front LIP Temporal Distribution MaxFlow Depth Above                               Margin:A=
Ground                              Dooi Eliv -
Building                             Door Elev. Elevation         iltllaxWSE         Max,WSE,'
Door       Grid
                                                                          .., ft POI ID                                              ft PNPP                              ft.PNPP Number                          Number     Number    Datum        ft     uAvoaa          ,Ditum '      (ft) 1     U1Auxiliary Building 1AX 406       74326   620.504      0.13     619.29          620.22       0.3 2      U1Auxiliary Building 1AX404        74642   620.465      0.03     619.39          620.32       0.1 3      U1Auxiliary Building 1AX403        75274   620.456      0.58     619.29          620.22       0.2 4      U1Auxiliary Building 1M 407        68496   620.614      0.41     619.48          620.41       0.2 5      U1Auxiliary Building 1AX 405       68499   620.506      0.09     619.53          620.46       0.0 6       U1 TurbineBuilding    1TB307      59754   620.500      0.10     619.53          620.46       0.0 7       U1 TurbineBuilding    1TB308      58385   620.500      0.03     619.21          620.14       0.4 8       U1 TurbineBuilding    1TB306      61482   624.500      0.27     618.87          619.80       4. 7 9       U1 TurbineBuilding    1 T B3 1 6  71777   620.392      0.03     619.35          620.28       0.1 10        U1 HeaterBay        1 H B3 0 6  64199   620.410      0.03     619.16          620.09       0.3 11        U1 HeaterBay        1 H B3 1 0  68856   620.385      0.03     619.29          620.22       0.2 12        Ul HeaterBay        1 H B3 1 4  67868   620.870      0.05     619.74          620.67       o.2 13        U1 HeaterBay        1H8311      67870   620.416      0.05     619.36          620.29       0.1 14        Ul HeaterBay        1HB309      70808   620.610      0.03     619.46          620.39       0.2 15        U1 HeaterBay        1 H B3 0 8  71778   620.261      0.12     619.25          620.18       0.1 U1 TurbinePower 16          Complex           1TP306      73051   620.420      0.20     619.34          620.27       0.2 U1 TurbinePower 17          Complex           1TP303      67841   620.516      0.03     619.53          620.46       0.1 18      U1 Off Gas Building   10G303      63836   620.467      0.11     619.43          620.36       0.1 19      Ul Off Gas BuiHing    10G302      63499   620.431      0.08     619.43          620.36       0.1 20      U1 Off Gas Building   10G 304     61123   620.467      0.05     619.54          620.47       0.0 U1WaterTreatment 21           Building         0\ /T 101   55241   620.401      0.21     619.26          620.19       0.2 WaterTreatment 22           Building         owT103      55936   620.399      0.30     619.43          620.36       0.0 WaterTreatment 23           Building         owT102      58372    620.429     0.48     619.43          620.36       0.1 DieselGenerator 24           Building         oDG106      64479   620.512      0.18     619.63          620.56       0.0 PERRYNUCLEARPOWERPLANT                                                                     Page 2 o f 8

NTTF Recommendation         2.1 (HazardReevaluations).Flooding                                 Revision1 FirstEnergyCorporation                                                                      March2,2016 Updated Design Basis LIP Flood Hazard Results at Door Locations for Front LIP Temporal Distribution MaxFlow Depth .                                ',...'...:.
Above                               MarginA =,
                                                               , Ground.                             ?oor Elev -
                                                               'Elevation                            , MaxWE Building
                                 'Door Door Elev.                      .Max'WSE Grid                          ,, flt,.
POI ID                                              ft PNPP                                ft P.NPP Number                          Number      Number   Datum         ft     NAVD88 , DatOm,:               (ft)
DieselGenerator 25         Building           oDG105       u146   620.547       0.05    619.62            620.55       0.0 DieselGenerator 26         Building           oDG104       63813  620.680       0.03    619.78            620.71       0.0 DieselGenerator 27         Bu i l d i n g     oDG103       63478  620.650       0.03    619.75            620.68       0.0 DieselGenerator 28         Building           oDG102       63143  620.503       0.03    619.59            620.52       0.0 DieselGenerator 29         Building           o D G1 0 1   62808  620.487       0.03     619.52           620.45       0.0 30     RadwasteBuilding       oRW422       62470  620.459       0.11     619.52           620.45       0.0 31     RadwasteBuilding       oRW407       62132  620.393       0.14    619.50            620.43       0.0 32     RadwasteBuilding       oRW411       61457  620.435       0.10     619.44           620.37       0.1 33     RadwasteBuilding       oRW101       62819  620.473       0.40     619.43           620.36       0.1 Intermediate 34         Building            0 l B3 1 5  76859  620.594       0.59     619.31           620.24       0.3 Intermediate 35         Bu i l d i n g      0 l B3 1 6  78439  620.570       0.36     619.49           620.42       0.1 Intermediate 36         Building            o t B3 1 7  78120  620.416       0.33     619.53           620.46       0.0 37      ServiceBuilding       o s B1 1 3   71398  620.430       0.54     619.58           620.51       -0.1 38      ServiceBuilding       o s B1 1 4   71721  620.434       0.40    619.57            620.50       -0.1 39      ServiceBuilding       osB107       70749  620.466       0.58    619.59            620.52       -0.1 40      ServiceBuilding       osB104       70098  620.436       0.55    619.60            620.53       -0.1 41      ServiceBuilding       osB105       68131  620.493       0.57    619.64            620.57       -0.1 42      ServiceBuilding       osB108       66808  620.477       0.52    619.66            620.59       -0.1 43      ServiceBuilding       osB103       60476  620.482       0.51    619.68            620.61       -0.1 44      ServiceBuilding       osB102       &+810  620.461       0.51    619.66            620.59       -0.1 45      ServiceBuilding       osB101       64477  620.467       0.29     619.62           620.55       -0.1 46    U2Auxiliary   Building 2AX 403       78748  620.419       0.41     619.68           620.61       -0.2 47    U2Auxiliary   Building 24d,404       78745  620.415       0.28     619.71           620.64       -0.2 48    U2Auxiliary   Building  2AX 406      79062  620.439       0.31     619.73           620.66       -0.2 PERRYNUCLEARPOWERPLANT                                                                        Page o f 8

NTTF Recommendation        2.1 (HazardReevaluations): Flooding                        Revision1 FirstEnergyCorporation                                                            March2,2016 Updated Design Basis LIP Flood Hazard Results at Door Locations for Front LIP Temporal Distribution MaxFlow Depth Above                       MarginA:='
:Ground                      Door Elev -
                                                                                            'Max WSE Building                              Door Elev. Elevation     MaxWSE Door      Grid POI ID                                              ft PNPP                      ft PNPP Number                         Number    Number      Datum         ft    Nefosa   Datum        '{ft}',:
49    U2Auxiliary Building 2AX405       73000     620.546      0.30    619.55   620.48        0.1 50    U2Auxiliary Building zpx 407      72041     620.469      0.47    619.57   620.50        0.0 51     U2TurbineBuilding      2TB-E     77146     620.499      0.34    619.77   620.70        -0.2 52     U2TurbineBuilding      2TB-D     77780     620.426      0.43    619.77   620.70        -0.3 53     U2 TurbineBuilding    2TB316     80003     620.440      0.63    619.80   620.73        -0.3 54     U2TurbineBuilding      2rB-C     80320     620.311      0.70    619.80   620.73        -0.4 55     U2TurbineBuilding     2TB306     70722     624.500      0.43    619.71   620.64        3.9 56     U2TurbineBuilding      2TB-B     66782     620.373      0.63    619.70   620.63        -0.3 57     U2TurbineBuilding     2TB308     67445     620.318      0.53    619.70   620.63        -0.3 58     U2TurbineBuilding      2TB-A     65462     620.325      0.54    619.76   620.69        -0.4 59     U2TurbineBuilding     2TB 307    66130     620.311      0.49    619.75   620.68        -0.4 60       U2 HeaterBay        2HB303     78716     620.476      0.65    619.81   620.74        -0.3 61       U2 HeaterBay        2HB306     74889     620.430      0.88    619.75   620.68        -0.2 U2TurbinePower 62         Complex           2TP303     72999     620.377      0.28    619.55   620.48        -0.1 63     U2 Off Gas Building   20G 304    66467     620.461      0.59    619.74   620.67        -0.2 64     U2 Off Gas Building   20G 302    68454     620.422      0.47    619.59   620.52        -0.1 65     U2 Off Gas Building   20G 303    68782     620.477      0.48    619.60   620.53        -0.1 66    ServiceWater Pump      SW102      58081     620.000      0.15    618.55   619.48        0.5 67    ServiceWater Pump       SW105     6 11 8 3  620.000      0.29    618.75   619.68        0.3 68    ServiceWater Pump      sw 103     57039     620.000      0.08    618.17   619.10        0.9 69    ServiceWater Pump      SW 104     56698     620.000      0.28    618.42   619.35        0.6 70    ServiceWater Pump      SW 101     6 11 9 0  620.000      0.54    618.80   619.73        0.3 Emergency  Water 71            Pump            EW 202    65576     619.500      0.44    618.90   619.83        -0.3 Emergency  Water 72            Pump            EW201     64916     619.500      0.54    619.09   620.O2        -0.5 Emergency  Water 73            Pump           EW East    66916     619.500      0.65    619.10   620.03        -0.5 Circulating Water 74            Pump          u2 cw 101 96539       621.500       0.39   620.59    621.52        0.0 PERRYNUCLEARPOWERPLANT

NTTF Recommendation       2.1 (HazardReevaluations):Flooding                         Revision1 FirstEnergyCorporation                                                           March2,2016 Updated Design Basis LIP Flood Hazard Results at Door Locations for Front LIP Temporal Distribution MaxFlow Depth Above'                       MarginA =
Ground                       Door,EIev,-
Building                            Door Elev. Elevation       MaxWSE        :MaxWSE Door      Grid POI ID                                            ft PNPP                 ft     ft PNPP Number                        Number    Number     Datum        ft     NAVD88     Daturn.      (ft)
CirculatingWater 75          Pu mp          u2 cw 102   96901    621.500      0.80     620.60    621.53       0.0 CirculatingWater 76          Pump           u2 cw 103 97636      626.500      0.07     620.92    621.85       4.7 CirculatingWater 77          Pump           u2 cw 104   95463    626.500      0.03     624.38    625.31       1.2 CirculatingWater      U2 CW 78          Pump             South     97994    624.500      0.40     620.61    621.54       3.0 CirculatingWater 79          Pump           u1 cw 101 83930      621.500      0.13     619.95    620.88       0.6 CirculatingWater 80          Pump           u1 cw 102 83929      621.500      0.03     619.95    620.88       0.6 CirculatingWater 81          Pump           u1 cw 103 85532      626.500      0.03     620.85    621.78       4.7 CirculatingWater 82          Pump           u1 cw 104 84900      626.500      0.03     624.55    625.48       1.0 CirculatingWater      U1 CW 83          Pump             South     84887    624.500      0.27     620.22    621.15       3.3 PERRYNUCLEARPOWERPLANT                                                              Page 5 of 8

NTTF Recommendation          2.1 (HazardReevaluations):       Flooding                       Revision1 FirstEnergyCorporation                                                                    March2,2016 Updated Design Basis LIP Flood Hazard Results Flood Duration above Door Elevationfor Front Temporal Distribution POI ID                                                                 MaximumWaterSurface Number          Building                    Door     Flooding Duration       Etevation Number           Hours          ft PNPPDatum 1       U1Auxiliary     Building        1AX 406     Door Not Flooded         620.2 2       U1Auxiliary     Building        1AX 404     Door Not Flooded         620.3 3       U1Auxiliary     Building        1AX403      Door Not Flooded         620.2 4       U1Auxiliary     Building        1AX 407     Door Not Flooded         620.4 5       U1Auxiliary     Building        1AX 405     Door Not Flooded         620.5 6       U1 TurbineBuilding              1TB307      Door Not Flooded         620.5 7       U1 TurbineBuilding              1TB308      Door Not Flooded         620.1 I       U1 TurbineBuilding              1TB306      Door Not Flooded         619.8 I       U 1 T u rb i n eB u i l d i n g 1 T B3 1 6  Door Not Flooded         620.3 10         Ul HeaterBay                 1HB306      Door Not Flooded         620.1 11         Ul HeaterBay                 1 H B3 1 0  Door Not Flooded         620.2 12         Ul HeaterBay                 1 H B3 1 4  Door Not Flooded         620.7 13         Ul HeaterBay                 1 H B3 1 1  Door Not Flooded         620.3 14         Ul HeaterBay                 1HB 309     Door Not Flooded         620.4 15         Ul HeaterBay                 1 H B3 0 8  Door Not Flooded         620.2 U1TurbinePower 16            Complex                   1TP306      Door Not Flooded         620.3 U1 TurbinePower 17            Complex                   1TP303      Door Not Flooded         620.5 18      U1 Off Gas Building             10G 303     Door Not Flooded         620.4 19      U1 Off Gas Building             10G302      Door Not Flooded         620.4 20      U1 Off Gas Building             10G 304     Door Not Flooded         620.5 U1 WaterTreatment 21             Building                 owT101      Door Not Flooded         620.2 U1 WaterTreatment 22             Building                 owT103      Door Not Flooded         620.4 U1 WaterTreatment 23             Building                 owT102      Door Not Flooded         620.4 DieselGenerator 24             Building                 oDG106      Door Not Flooded         620.6 Diesel Generator 25             Building                 oDG105      Door Not Flooded         620.6 DieselGenerator 26             Building                 oDG104      Door Not Flooded         620.7 DieselGenerator 27             Building                 oDG103      Door Not Flooded         620.7 PERRYNUCLEARPOWERPLANT                                                                      Page 6 of 8

NTTF Recommendation      2.1 (HazardReevaluations): Flooding                         Revision1 FirstEnergyCorporation                                                          M a r c h2 . 2 0 1 6 Updated Design Basis LIP Flood Hazard Results Flood Duration above Door Elevation for Front Temporal Distribution POI ID                                                       Maxim,umWaterSurface Number         Building           Door     Flooding Duration       Elevation Number           Hourc          ft PNPPDatum DieselGenerator 28            Building       oDG102       Door Not Flooded         620.5 DieselGenerator 29            Building       o D G1 0 1   Door Not Flooded         620.5 30       RadwasteBuilding    oRW422       Door Not Flooded         620.5 31       RadwasteBuilding    oRW407       Door Not Flooded         620.4 32       RadwasteBuilding    oRW411       Door Not Flooded         620.4 33       RadwasteBuilding    oRW 101      Door Not Flooded         620.4 34     IntermediateBuilding   o t B3 1 5  Door Not Flooded         620.2 35      IntermediateBuilding  o t B3 1 6  Door Not Flooded         620.4 36      IntermediateBuilding  0 l B3 1 7  Door Not Flooded         620.5 37        ServiceBuilding    o s B1 1 3         0.7                620.5 38        ServiceBuilding    o s B1 1 4         0.6                620,5 39        ServiceBuilding    osB107             0.3                620.5 40        ServiceBuilding    osB104             0.8                620.5 41        ServiceBuilding    osB105             0.5                620.6 42        ServiceBuilding    osB108             0.9                620.6 43        ServiceBuilding    osB103             1.0                620.6 44        ServiceBuilding    osB102             1.0                620.6 45        ServiceBuilding    OSB1 0 1           0.6                620.6 46      U2AuxiliaryBuilding  2AX 403            1.6                620.6 47      U2AuxiliaryBuilding  2M 404             2.3                620.6 48      U2AuxiliaryBuilding  2AX 406            3.1                620.7 49      U2AuxiliaryBuilding  2AX405       Door Not Flooded         620.5 50      U2AuxiliaryBuilding  zFX 407      Door Not Flooded         620.5 51       U2TurbineBuilding     2TB-E            2.1                620.7 6.2(usemaximum 52       U2TurbineBuilding     2TB-D         of 6 hrs)             620.7 53       U2TurbineBuilding   2TB316             1.8                620.7 54       U2 TurbineBuilding    2TB-C            3.8                620.7 55       U2TurbineBuilding   2TB306       Door Not Flooded         620.6 6.8(usemaximum 56       U2 TurbineBuilding    2TB-B         of 6 hrs)             620.6 9.7(usemaximum 57       U2 TurbineBuilding   2TB308         of 6 hrs)             620.6 PERRYNUCLEARPOWERPLANT                                                             Page 7 of 8

NTTF Recommendation      2.1 (HazardReevaluations):
Flooding                        Revision1 FirstEnergyCorporation                                                         March2,2016 Updated Design Basis LIP Flood HazardResults Flood Duration above Door Elevationfor Front Temporal Distribution POI ID                                                     MaximurnWaterSurface Number         Building           Door   Flooding Duration        Elevation Number         Hours          ft PNPPDatum 58      U2TurbineBuilding      2TB-A           4.0                620.7 59      U2 TurbineBuilding    2TB 307          3.5                620.7 60        U2 HeaterBay        2HB303           1.7                620.7 61        U2 HeaterBay        2HB306           5.8                620.7 U2TurbinePower 62           Complex          2TP303           1.3               620.5 63      U2 Olf Gas Building   20G 304          1.5                620.7 64      U2OffGasBuilding      20G 302          0.9                620.5 65      U2OffGasBuilding      20G 303          0.3                620.5 66      ServiceWater Pump     SW 102    Door Not Flooded         619.5 67      ServiceWater Pump      SW105    Door Not Flooded          619.7 68      ServiceWater Pump     SW 103    Door Not Flooded          619.1 69      ServiceWater Pump     SW 104    Door Not Flooded          619.4 70      ServiceWater Pump     SW 101    Door Not Flooded          619.7 Emergency  Water              6.1(usemaximum 71             Pump           EW 202        of 6 hrs)            619.8 Emergency  Water              10.0(usemaximum 72             Pump           EW 201        of 6 hrs)             620.0 Emergency  Water              7.3(usemaximum 73             Pump           EW East       of 6 hrs)             620.0 74    CirculatingWaterPump   u2 cw 101  Door Not Flooded          621.5 75    CirculatingWaterPump   u2 cw 102  Door Not Flooded          621.5 76    CirculatingWater Pump  u2 cw 103  Door Not Flooded          621.8 77    CirculatingWaterPump   u2 cw 104  Door Not Flooded          625.3 U2 CW 78    CirculatingWaterPump     South    Door Not Flooded          621.5 79    CirculatingWaterPump   ul cw 101  Door Not Flooded          620.9 80    CirculatingWaterPump   u1 cw 102  Door Not Flooded          620.9 81    CirculatingWaterPump   u1 cw 103  Door Not Flooded          621.8 82    CirculatingWater Pump  u1 cw 104  Door Not Flooded          625.5 U1 CW 83    CirculatingWaterPump     South    Door Not Flooded          621.2 PERRYNUCLEARPOWERPLANT                                                           Page 8

NTTF Recommendation  2.1 (HazardReevaluations):
Flooding                 Revision1 FirstEnergyCorporation                                             March2.2016 ATTACHMENT      2 Beyond Design Basis LIP Flood Hazard Results End TemporalDistribution (ReferencePNPP2016c)
PERRYNUCLEARPOWERPLANT                                               Page 1 of 8

NTTF Recommendation       2.1 (HazardReevaluations):    Flooding                                    Revision1 FirstEnergyCorporation                                                                       March2.2016 Beyond Design Basis LIP Flood Hazard Results at Door Locations for Elnod Lil- l empora lDistribution LIP Ten Max Flow Depth Above                                   MarginA.=
Ground ,                                DoorElev-Building                              Door Elev. rElevation      MaxWSE                      Max WSE'
                                                                                   '.'..'.'....,'.        r t - .
Door       Grid POI ID                                               ft PNPP                                ft'PNPP Number                          Number     Number     Datum            ft     ;A$            .....t,,-
                                                                                            ,Datum                (ft) 1     U1Auxiliary Building 1AX 406       74326     620.504         0.51     619.67        620.60               -0.1 2      Ul AuxiliaryBuilding 1AX 404       74642     620.465         0.33     619.69        620.62               -0.2 3      U1Auxiliary Building 1AX403        75274     620.456         1.02     619.73        620.66               -0.2 4      Ul AuxiliaryBuilding 1A.X,407      68496     620.614         0.69     619.76        620.69               -0.1 5      U1Auxiliary Building 1AX405        68499     620.506         0.32     619.76        620.69               -0.2 6       U1TurbineBuilding     1TB307      59754     620.500         0.31     619.74        620.67               -0.2 7       U1 TurbineBuilding    1TB308      58385     620.500         0.08     619.26        620.19               0.3 8       U1 TurbineBuilding    1TB306      61482     624.500         0.38     618.98        619.91               4. 6 I       U1 TurbineBuilding    1 T B3 1 6  71777     620.392         0.30     619.62        620.55               -o.2 10        U1 HeaterBay        1HB306      64199     620.410         0.05     619.18        620.11                0.3 11        Ul HeaterBay        1 H B3 1 0  68856     620.385         0.26     619.52        620.45               -0.1 12        U1 HeaterBay        1 H B3 1 4  67868     620.870         0.10     619.79        620.72                0.2 13        U1 HeaterBay        1H8311      67870     620.416         0.14     619.45        620.38                0.0 14        U1 HeaterBay        1HB309      70808     620.610         0.15     619.58        620.51                0.1 15        U1 HeaterBay        1 H B3 0 8  71778     620.261         0.49     619.62        620.55               -0.3 U1TurbinePower 16          Complex           1TP306      73051     620.420         0.52     619.66        620.59               -0.2 U1TurbinePower 17           Complex          1TP303      67841     620.516         0.26     619.76        620.69               -0.2 18      Ul Off Gas Building   10G303      63836     620.467         0.37     619.69        620.62               -0.2 19      U1 Off Gas Building   10G302      63499     620.431         0.34     619.69        620.62               -0.2 20      Ul Off Gas Building   10G 304     61123     620.467         0.24     619.73        620.66               -0.2 U1 WaterTreatment 21           Building         owT101      55241     620.401         0.45     619.50        620.43                0.0 WaterTreatment 22           Building         owT103      55936     620.399         0.58     619.71        620.64               -0.2 WaterTreatment 23           Building         owT102      58372     620.429         0.79     619.74        620.67               -0.2 PERRYNUCLEARPOWERPLANT                                                                             Page 2 of 8

NTTF Recommendation       2.1 (HazardReevaluations).      Flooding                            Revision1 FirstEnergyCorporation                                                                     March2,2016 Beyond Design Basis LIP Flood Hazard Results at Door Locations   s for End LIP Ten emDora I Distribution Max Flow Depth Above              ..          MarginA,=
Ground                         Door Elev-Building                                   Door Elev. Elevation       M"xwie''         MaxWSE Door        Grid POIID                                                   ft PNPP                           ft PNPP Number                         Number      Number        Datum         ft      nr$oaa      Datum       ,,,{ft)
DieselGenerator 24         Building          oDG106       6/,479      620.512       0.44      619.89     620.82       -0.3 DieselGenerator 25         Bu i l d i n g    oDG105       64146       620.547       0.31      619.88     620.81       -0.3 DieselGenerator 26         Bu i l d i n g    oDG104       63813       620.680       0.11      619.86     620.79      -0.10 DieselGenerator 27         Building          oDG103       63478       620.650       0.13      619.85     620.78       -0.1 DieselGenerator 28         Building          oDG102       63143       620.503       0.27      619.83     620.76       -0.3 DieselGenerator 29         Building          o D G1 0 1   62808       620.487       0.30      619.79     620.72       -0.2 30     RadwasteBuilding      oRW422       62470       620.459       0.39      619.80     620.73       -0.3 31     RadwasteBuilding      oRW407       62132       620.393       0.44      619.80     620.73       -0.3 32     RadwasteBuilding      oRW411       61457       620.435       0.40      619.74     620.67       -0.2 33     RadwasteBuilding      oRW101       62819       620.473       0.66      619.69     620.62       -0.1 Intermediate 34         Building           o t B3 1 5  76859       620.594       1.07      619.79     620.72       -0.1 Intermediate 35         Bu i l d i n g     o t B3 1 6  78439       620.570       0.84      619.97     620.90       -0.3 Intermediate 36         Building           o t B3 1 7  78120       620.416       0.79      619.99     620.92       -0.5 37      ServiceBuilding      o s B1 1 3   71398       620.430       0.91      619.95     620.88       -0.4 38      ServiceBuilding      o s B1 1 4   71721       620.434       0.78      619.95     620.88       -0.4 39      ServiceBuilding      osB107       70749       620.466       0.95      619.96     620.89       -0.4 40      ServiceBuilding      osB104       70098       620.436       0.92      619.97     620.90       -0.5 41      ServiceBuilding      osB105       68131       620.493       0.93      620.00     620.93       -0.4 42      ServiceBuilding      osB108       66808       620.477       0.89      620.03     620.96       -0.5 43      ServiceBuilding      osB103       66476       620.482       0.86      620.03     620.96       -0.5 44      ServiceBuilding      osB102       64810       620.461       0.83      619.98     620.91       -0.5 45      ServiceBuilding      osB101       64r'.77     620.467       0.58      619.91     620.84       -0.4 PERRYNUCLEARPOWERPLANT                                                                       Page 3 of 8

NTTF Recommendation       2.1 (HazardReevaluations):     Flooding                                 Revision1 FirstEnergyCorporation                                                                        March2,2016 Beyond Design Basis LIP Flood Hazard Results at Doorr Locations   for End LIP Temporal ns Tor             em        Distribution Max Flow Depth ,
Above                                MargihA:=
Ground                               Door'El6i ,.-
Building                                 Door Elev. Elevation            Max WSE          ,MaxWSE Door      Grid                                 : , f t , , . ft PNPP POI ID                                                 ft PNPP Number                         Number    Number         Datum         ft      NAVD88 Daturn                 (ft) 46    U2Auxiliary Building 2AX403       78748        620.419      0.78       620.05          620.98      -0.6 47    U2Auxiliary Building zPY\404      78745        620.415      0.65       620.08          621.01      -0.6 48    U2Auxiliary Building 2AX 406      79062        620.439      0.67       620.09          621.02      -0.6 49    U2Auxiliary Building   24X.405    73000        620.546      0.69       619.94          620.87      -0.3 50    U2Auxiliary Building zPJ\407      72041        620.469      0.85       619.95          620.88       -0.4 51     U2 TurbineBuilding     2TB.E     77146        620.499      0.71       620.14          621.07      -0.6 52     U2 TurbineBuilding     2TB-D     77780        620.426      0.80       620.14          621.07      -0.6 53     U2TurbineBuilding     2TB316     80003        620.440      1.20       620.37          621.30      -0.9 54     U2TurbineBuilding      2TB-C     80320        620.311      1.30       620.40          621.33      -1.0 55     U2TurbineBuilding     2TB306     70722        624.500      0.90       620.18          621.11       3.4 56     U2TurbineBuilding      2TB.B     66782        620.373      1.09       620.16          621.09       -0.7 57     U2TurbineBuilding     2TB308     67445        620.318      0.99       620.16          621.09      -0.8 58     U2 TurbineBuilding     2TB-A     65462        620.325      0.89       620.11          621.04       -0.7 59     U2 TurbineBuilding    2TB 307    66130        620.311      0.84       620.10          621.03       -0.7 60       U2 HeaterBay        2HB303     78716        620.476       1.25      620.41          621.34      -0.9 61       U2 HeaterBay        2HB306     74889        620.430      1.38       620.25          621.18       -0.7 U2TurbinePower 62         Complex           2TP303     72999        620.377      0.67       619.94          620.87      -0.5 63     U2 OffGasBuilding 20G 304        66467        620.461      0.93       620.08          621.01      -0.6 64     U2 Off Gas Building   20G 302    68/.54       620.422      0.89       620.01          620.94      -0.5 65     U2 Off Gas Building   20G 303    68782        620.477      0.89       620.01          620.94       -0.5 66    ServiceWater Pump       SW 102    58081        620.000      0.27       618.67          619.60       0.4 67    ServiceWater Pump       SW105     6 11 8 3     620.000      o.57       619.03          619.96       0.0 68    ServiceWater Pump       SW 103    57039        620.000      0.27       618.36          619.29       0.7 69    ServiceWater Pump       SW 104    56698        620.000      0.47       618.61          619.54       0.5 70    ServiceWater Pump       SW 101    61190        620.000      0.87       619.13          620.06       -0.1 Emergency  Water 71            Pump            EW202     65576        619.500      0.84       619.30          620.23       -0.7 PERRYNUCLEARPOWERPLANT                                                                           Page 4 of 8

NTTF Recommendation     2.1 (HazardReevaluations):     Flooding                            Revision1 FirstEnergyCorporation                                                                M a r c h2 , 2 0 1 6 Beyond Design Basis LIP Flood Hazard Results at Door Lco ccations for End LIP Ten empora I Distribution Max Flow Depth Above ,                          MarginA =
Giouhd                           Door Etev-Building                               Door Elev. Elevation       MaxWSE            :,MaxUtlS! '
Door        Grid                             ' ft, POI ID                                              ft PNPP                         ,ft PNP-P Number                       Number      Number       Datum          ft     NAVD88 Datum                 {ft}
EmergencyWater 72          Pump            EW 201      64916      619.500        1.00     619.55    620.48             1.0 EmergencyWater 73          Pump           EWEast       66916      619.500        1.10     619.55    620.48             1.0 CirculatingWater 74          Pump          u2 cw 101 96539          621.500        a.82     621.02    621.95           -0.5 CirculatingWater 75          Pump          u2 cw 102     96901      621.500        1.23     621.03    621.96           -0.5 CirculatingWater 76          Pu mp         u2 cw 103 97636          626.500        0.28     621.13    622.06            4.4 CirculatingWater 77          Pump          u2 cw 104     95463      626.500        0.08     624.43    625.36            1.1 CirculatingWater     U2 CW 78          Pump             South      97994      624.500        0.84     621.05    621.98            2.5 CirculatingWater 79          Pump          u 1c w 1 0 1 83930       621.500        0.20     620.02    620.95            0.6 CirculatingWater 80          Pump          u1 cw 102 83929          621.500        0.06     619.98    620.91            0.6 CirculatingWater 81          Pump          u1 cw 103 85532          626.500        0.22     621.04    621.97            4. 5 CirculatingWater 82          Pump          u1 cw 104 84900          626.500        0.03     624.55    625.48            1.0 CirculatingWater     U1 CW 83          Pump             South      84887      624.500        0.45     620.40    621.33            3.2 PERRYNUCLEARPOWERPLANT                                                                   Page 5 of 8

NTTF Recommendation              2.1 (HazardReevaluations): Flooding                       Revision1 FirstEnergyCorporation                                                                 March2,2016 Beyond Design Basis LIP Flood Hazard Results Flood Duration above Door Elevationfor End Temporal Distribution POI ID                                                                          MaximumWater Number                Building                    Door       Flooding rDuration Suface Elevation Number             Hours         ft PNPPDatum 1   U1Auxiliary      Building               1AX 406             0.30              620.6 2    U1Auxiliary      Building               1pJ<404             0.40              620.6 3    U1Auxiliary      Building               1AX403              0.40              620.7 4    U1Auxiliary      Building               1AX 407             0.10              620.7 5    U1Auxiliary      Building               1AX 405             0.20              620.7 6    U1 TurbineBuilding                      1TB307              0.40              620.7 7    U 1 T u rb i n eB u i l d i n g         1TB308        Door Not Flooded        620.2 8    U l T u rb i n eB u i l d i n g         1TB306        Door Not Flooded        619.9 9    U1 TurbineBuilding                      1 T B3 1 6          0.40              620.6 10   U1 HeaterBay                            1HB306        Door Not Flooded        620.1 11   U1 HeaterBay                            1 H B3 1 0          0.20              620.5 12   U1 HeaterBay                            1 H B3 1 4    Door Not Flooded        620.7 13   Ul HeaterBay                            1 H B3 1 1    Door Not Flooded        620.4 14   Ul HeaterBay                            1 H B3 0 9    Door Not Flooded        620.5 15   Ul HeaterBay                            1 H B3 0 8          0.50              620.6 16   U1 TurbinePowerComplex                  1TP306              0.40              620.6 17   U1 TurbinePowerComplex                  1TP303              0.20              620.7 18   U1 Off Gas Building                     10G 303             0.20              620.6 19   U1 Off Gas Building                     10G302              0.30              620.6 20   U1 Off Gas Building                     10G 304             0.90              620.7 21   U1 WaterTreatmentBuilding               OWT1 0 1      Door Not Flooded        620.4 22   U1WaterTreatment               Building owT103              0.50              620.6 23   U1WaterTreatment               Building owT102              0.50              620.7 24   DieselGeneratorBuilding                 oDG106              0.80              620.8 25   DieselGeneratorBuilding                 oDG105              0.60              620.8 26   DieselGeneratorBuilding                 oDG104              0.40              620.8 27   DieselGeneratorBuilding                 oDG103              0.50              620.8 28   DieselGeneratorBuilding                 oDG102              0.70              620.8 29   DieselGeneratorBuilding                 o D G1 0 1          0.40              620.7 30   RadwasteBuilding                        oRW422              0.60              620.7 31   RadwasteBuilding                        oRW407              0.70              620.7 32   RadwasteBuilding                        oRW411              0.50              620.7 PERRYNUCLEARPOWERPLANT                                                                   Page 6 of 8

NTTF Recommendation     2.1 (HazardReevaluations):
Flooding                          Revision1 FirstEnergyCorporation                                                         March2.2016 Beyond Design Basis LIP Flood Hazard Results Flood Duration above Door Elevationfor End Temporal Distribution POI ID                                                                 MaximumWater Number           Building              Door        Flooding Duration    SurfaceElevation Number              Hours           ft PNPPDatum 33   RadwasteBuilding            oRW 101               0.20                620.6 34   IntermediateBuilding         0rB315               0.30                620.7 35   IntermediateBuilding         o t B3 1 6           0.50                620.9 36   IntermediateBuilding         o t B3 1 7           0.80                620.9 37   ServiceBuilding              o s B1 1 3           0.80                620.9 38   ServiceBuilding              o s B1 1 4           0.80                620.9 39   ServiceBuilding              osB107               0.80                620.9 40   ServiceBuilding              osB104               0.90                620.9 41   ServiceBuilding              osB105               0.80                620.9 42   ServiceBuilding              osB108               0.90                621.0 43   ServiceBuilding              osB103               0.90                621.0 44   ServiceBuilding              osB102               1.00                620.9 45   ServiceBuilding              osB101               0.80                620.8 46   U2AuxiliaryBuilding          2AX 403              1.20                621.0 47   U2AuxiliaryBuilding          zPX,404              1.60                621.0 48   U2AuxiliaryBuilding          2AX406               1.90                621.0 49   U2AuxiliaryBuilding          2AX 405              0.40                620.9 50   U2AuxiliaryBuilding          zAX 407              0.60                620.9 51   U2TurbineBuilding             2TB-E               1.60                621.1 6.10(use maximum  of 6 52   U2TurbineBuilding             2TB-D              hour)                621.1 53   U2TurbineBuilding            2TB316               1.30                621.3 54   U2TurbineBuilding             2TB-C               1.70                621.3 55   U2TurbineBuilding            2TB 306        Door Not Flooded          621.1 56   U2TurbineBuilding             2TB.B               4.40                621.1 6.50(usemaximum   of 6 57   U2TurbineBuilding            2TB308              hour)                621.1 58   U2TurbineBuilding             2TB-A               1.90                621.0 59   U2 TurbineBuilding           2TB 307              1.80                621.0 60   U2 HeaterBay                 2HB303               1.30                621.3 61   U2 HeaterBay                 2HB306               2.70                621.2 62   U2 TurbinePowerComplex       2TP303               1.00                620.9 63   U2 Off Gas Building          20G 304              1.20                621.0 64   U2 Off Gas Building          20G 302              0.90                620.9 PERRYNUCLEARPOWERPLANT                                                           Page 7 of 8

NTTF Recommendation      2.1 (HazardReevaluations):
Flooding                          Revision1 FirstEnergyCorporation                                                         March2.2016 Beyond Design Basis LIP Flood Hazard Results Flood Duration above Door Elevationfor End Temporal Distribution POI ID                                                                  MaximumWater Number            Building              Door       Flooding Duration    SurfaceElevation Number             Hours           ft PNPPDatum 65   U2 Off Gas Building           20G 303             0.80                620.9 66   ServiceWater Pump             SW 102        Door Not Flooded          619.6 67   ServiceWater Pump              SW105        Door Not Flooded          620.0 68   ServiceWater Pump             SW 103        Door Not Flooded          619.3 69   ServiceWater Pump             SW 104        Door Not Flooded          619.5 70   ServiceWater Pump             SW 101              0.10                620.1 71   Emergency  WaterPump          EW 202              5.80                620.2 7.50(usemaximum   of 6 72   Emergency  WaterPump          EW 201             hour)                620.5 7.10(usemaximum   of 6 73   Emergency  WaterPump          EW East            hour)                620.5 74   CirculatingWaterPump         u2 cw 101            0.70                622.0 75   CirculatingWaterPump         u2 cw 102            0.70                622.0 76   CirculatingWaterPump         u2 cw 103      Door Not Flooded          622.1 77   CirculatingWaterPump         u2 cw 104      Door Not Flooded          625.4 78   CirculatingWater Pump       U2 CW South     Door Not Flooded          622.0 79   CirculatingWaterPump         u1 cw 101      Door Not Flooded          620.9 80   CirculatingWaterPump         u1 cw 102      Door Not Flooded          620.9 81   CirculatingWaterPump         u1 cw 103      Door Not Flooded          622.0 82   CirculatingWater Pump        u1 cw 104      Door Not Flooded          625.5 83   CirculatingWaterPump        U1 CW South     Door Not Flooded          621.3 PERRYNUCLEARPOWERPLANT                                                           Page I of 8}}