NRC 2012-0100, Response to 10 CFR 50.54(f) Request for Information Regarding Near-Term Task Force Recommendation 2.3, Flooding

Response to 10 CFR 50.54(f) Request for Information Regarding Near-Term Task Force Recommendation 2.3, Flooding

ML12326A713
Person / Time
Site:	Point Beach
Issue date:	11/20/2012
From:	Meyer L Point Beach
To:	Office of Nuclear Reactor Regulation, Document Control Desk
References
NRC 2012-0100 NEE05-PR-001, Rev 0
Download: ML12326A713 (23)

Text

NEXT; November 20,2012 POINT BEACH NRC 201 2-01 00 10 CFR 50.54(f)

U.S. Nuclear Regulatory Commission ATTN: Document Control Desk Washington, DC 20555-0001 Point Beach Nuclear Plant, Units 1 and 2 Docket 50-266 and 50-301 Renewed License Nos. DPR-24 and DPR-27 NextEra Energy Point Beach, LLC Response to 10 CFR 50.54(f) Request for lnformation Regardinn Near-Term Task Force Recommendation 2.3, Flooding

References:

(I)

NRC letter to All Power Reactor Licensees and Holders of Construction Permits in Active or Deferred Status, dated March 12, 2012, Request for lnformation Pursuant to Title 10 of the Code of Federal Regulations 50.540 Regarding Recommendations 2.1, 2.3, and 9.3, of the Near-Term Task Force Review of lnsights from the Fukushima Dai-lchi Accident (MLI 2056A046)

(2)

NextEra Energy Point Beach, LLC letter to NRC, dated June 8, 2012, NextEra Energy Point Beach, LLC's Response to NRC Request for lnformation Pursuant to 10 CFR 50.540 Regarding Recommendations 2.1 and 2.3 of the Near-Term Task Force Review of lnsights from the Fukushima Dai-lchi Accident (MLI 21 63A250)

(3)

NRC letter to Nuclear Energy Institute, dated May 31, 2012, Endorsement of Nuclear Energy lnstitute (NEI) 12-07, "Guidelines for Performing Verification Walkdowns of Plant Flood Protection Features,"

(ML12144A142)

On March 12, 2012, the NRC staff issued Reference (I), requesting information pursuant to 10 CFR 50.54(f). Enclosure 4 of Reference (1) contains specific Requested Actions and Requested lnformation associated with Recommendation 2.3 for Flooding. Requested lnformation Item 2 of Reference (I), Enclosure 4, requested addressees conduct a flooding walkdown and submit a final report which addressed various requirements detailed in the item.

Reference (I), Enclosure 4 required addressees submit a final flooding walkdown report within 180 days of the NRC's endorsement of the flooding walkdown procedure.

Via Reference (2), NextEra Energy Point Beach, LLC (NextEra) confirmed it will use the NRC-endorsed flooding walkdown procedure Nuclear Energy Institute (NEI) 12-07, Guideline for Performing Verification Walkdowns of Plant Flood Protection Features, Revision 0, and submit a report by November 27,2012, which corresponds to 180 days after the NRC endorsed the NEI flooding walkdown guidance (Reference 3).

NextEra Energy Point Beach, LLC, 6610 Nuclear Road, Two Rivers, W1 54241

Document Control Desk Page 2 provides Flooding Walkdown Report NEE05-PR-001, Revision 0, which was prepared in accordance with the guidance of NEI 12-01, Revision 0, and provides the requested flooding walkdown information. This submittal completes the NextEra response to the Requested Information of Reference (I), Enclosure 4.

This letter contains no new Regulatory Commitments and no revision to existing Regulatory Commitments.

If you have any questions please contact Mr. Michael Millen, Licensing Manager, at 9201755-7845, I declare under penalty of perjury that the foregoing is true and correct.

Executed on November 20,2012.

Very truly yours, NextEra Energy Point Beach, LLC Site Vice President Enclosure cc:

Administrator, Region Ill, USNRC Project Manager, Point Beach Nuclear Plant, USNRC Resident Inspector, Point Beach Nuclear Plant, USNRC Director, Office of Nuclear Reactor Regulation, USNRC

ENCLOSURE 1 NEXTERA ENERGY POINT BEACH, LLC POINT BEACH NUCLEAR PLANT, UNITS I AND 2 NEXTERA ENERGY POINT BEACH, LLC RESPONSE TO 10 CFR 50.54(F)

REQUEST FOR INFORMATION REGARDING NEAR-TERM TASK FORCE RECOMMENDATION 2.3, FLOODING FLOODING WALKDOWN REPORT NEE05-PR-001 REVISION 0 20 pages follow

FLOODING WALKDOWN REPORT NEE05-PR-001, Rev 0 IN RESPONSE TO THE 50.54(f) INFORMATION REQUEST REGARDING NEAR-TERM TASK FORCE RECOMMENDATION 2.3: FLOODING for the Point Beach Nilclear Plant 6610 Nuclear Rd, 'IWo Rivers, WI 54241 Facility Operating License No. DPR-24 and DPR-27 NRC Docket No. 50-266 and 50301 NextErn Energy Resources 700 Universe Boulevard Juno Be~cl~,

FL 33408 Prepared by:

ENERCON Services, Inc.

2056 Wcsti~tgs Avenue, Suite 140 N~perville, IL 60563

NTTF Recommendation 2.3 (Walkdowns): Flooding NexlEra Energy Resources.

PBNP Novetr~ber 14. 20 12 NEOOS-PR-00 1. Revision 0 Con tell tar I. EXECUTIVE

SUMMARY

2 2. PURPOSE............................................................................................................................................... 3 a

Background

3 b. Site Description............................................................................................................................

4 3. ME'l'HODOLOaY

$4 4. REQUESTED INFORMATION..............................................................................................................

4 n. Requested l~ifontiatio~i ltetn 2(a) - Desig~i Basis Flood Hazards.............................,.......................... 4 b. Roq~losted Itiformatiot~ Itetn 2(b) - CLB Protection a~rd Mitigatbr Peattr~res.

-5 c. Requested Infor~i~ation Item 2(c) - Flood Wnrnitig Systerns...........................................................

7 d. Requested l~lfonnation ltern 2(d) - Flood Protectio~i SystemlBarrier Effective~iess.............................

7 e. Requested lnfonnation Item 2(e) - I~nplotne~~tatio~~

of Walkdown P~uoess......................................,..

I0

f.

Requested I~~for~nation ite~ir 2(f) - Findings and Corrective Actions TakenIPlanaed......................

I I g. Requested lnforrnntiorr Itc~n 2(g) - Cliff-Edge Effects ntrd Avnilnble Pliysical Margin................... 14

11.

Requested l~iforrnntio~i Item 2(B) - PIaat~edMewly-lnstnlled Flood P~utectior E~ilratice~ne~rts 14 5. CONCLUSIONS......................................................................................................................................

I4

6.

REFERENCES.......................

16 7. ATTACHMENTS................................................................................................................................

1 7

Page 1 of 19

NTTF Reco~nmendrtio~r

2.3 (Walkdowns)

Flooding NextEm Energy Resources - PBNP Nove~nbcr 14,2012 NEEOS-PR-001, Revision 0 1, EXECUTIVE

SUMMARY

This report wvas developed to provide inforniatio~~

requested by the United States Nuclear Regulatory Co~nmission (NRC) pul*saant to Title 10 of tlte Code of Federal Regulations, Section 50.54 (0 [Ref. 21 011 MRICII 12,2012 for the Point Bemcli Nuclear Plant (PBNP). hr rsesponse to tlie NRC request, NexlEra Energy Resources pefiorrned walkdow~ls to verify thnt p h ~ t features credited in the n~rrent lice~~sing basis (CLB) for protectio~i and nritigatio~r fir0111 external flood events are available, krctioonl, nnd properly maintained. The walkdowns were perfo~~~ned to vorify Illat pennane~J structures, systetns, compone~~ts (SSCs), portable flood

~llitigation equipmest, and the procedures needed to install md or operate tl~eni during a flood are acceptable and capable of perfor~ni~rg their design fi~nction 8s credited in the CLB.

Walkdowtls were perforrricd in accorda~~ce with NEl 12-07 (Rev. 0-A), "Guidelines fbr Perfornling Verification of Plant Plood Protection Features", dated May, 2012 [Ref. I].

Tlris documeat was elldomed by the NRC 011 May 31, 2012. PBNP Units I & 2 co~lfigr~ration and proccdures were compared to tlre flood protection featt~res credited in tlre current lice~rsing basis doci~~nents for exterirrl flooding everts.

Site-specific feahlres creclited for protection r ~ l d lnitigntio~i rtgalnst extemrl flooding events were identi fled and evaluated. A sirtnlnrrly of the PBNP CLB, flood protection features and the rest~lts of tile inspections is provided below.

Current Lice~lsina Basis There are two design basis floods for PBNP: a probable ~nnxi~nt~~n wave rilrr-up from Lake Miclrignn and I co~nbi~led p~vbable tnaxinrt~~n rai~ifall md snowmelt. The probable nrrxi~nitm wave rua-up rerrches +8,42 R relative to tile plant's refererlce zero elevatiotl of 580,2 A Idet.~utioarl Orert Lakes Datum 1955 (IGLD) and has no dcfirred duratio~r. The second design basis flood conrbines a probable n~axi~nun~

six-hot~r rminfnll wvill~ the probable n~aximonr snow~nelt ill the seco~ld lralf of Maroll to genernle 1400 acre-ft of rusoff. This flood also llas no defined dartition, Vie floods are not assi~med to occur conourrently.

Flood Protectio~i Featu~ws Tile PBNP CLB does not state speaific plant co~~figurntlons during a flood cvent or the darn ti or^ of tile flood, The flood nitigntion syste~ns function lndepe~rdently of plnnt configuratio~i.

For tllo wave rilrr-up flood, tlte site provides temporary coircmte Jarsey barriers on the no1Z11 and south sides of tlro Citculati~rg Water Y~~tnp House (CWPH) Il~at provide protectiorr up to i-9 ft. A site procedure pm~npts the installation of the barriers based on tlro tusesl~lts of a tno~rtlrly clieck of the lake leval. For the possible water thnt could splash over or tl~ro~~glr the barriers, there are storm drains a~ound the CWPH, n~rd the lowvesl critical eqaipn~eat in tlre CWPH is ~iror~~rted at 4-9 ft. The Ileigl~t of the critical equip~nont docs not vary with respect to its operating mode; therefore tlla flood ~nitigatiori systetn re~nains independerit of plant corfigt~ratio~r.

Tile cornbi~~ccl rail1 rind ssowmell flood is lla~ldled by a co~nbinatiorr of the site's natural draiange, installed storm drain systeln ia the plant yard, rind various drainnp ditcl~es and culverts RI~IIII~

[lie site. The drainnge systeln provides a flow path to Lake Micl~ign~~

for the ru~roff generalad.

Page 2 of 19

NTTI: Recoml~ierrdatloll

2.3 (Walkdowes)

Flooding NextEra Energy Resources - PBNP November 14,2012 NEEOJ-PR-00 I, Revision 0 Inspection Resl~k Tlre colrcrcte jersey barriers inshllcd at the CWPH did not txterrd far enol~glr to the ~ro~tlr atid soullr to provide a barrier up to +9 R. Also due to ulrever ground and featt~res 011 tlre barriers, sotire gaps existed In tlre ilrslalled cotrfigt~ratios. Work requests were writterr to add dditional barriers nnd pour n co~rcrete pad to correct these issi~es.

Tlre site procedure for the installation of tlre concrele jersey barriers was fot~~rd to be deficient. It did not idelitify that tlre barriers were being i~rstalled in a B.5.b stagir~g RIWR a11d also did not provide perlinel~t isformatio~r for the support equipmelit tlral wvotlld be reeded, A pracedare clra~lge will be generated to address these issttos as well as i~rstiti~te n regular check on tlre stagilrg coliditiolr of the

barriers, Tlre corrtrol prnel and bnttery for the diesel fire pt~~mp it1 tlre CWPH webe below t9 It. The control panel, wlriclr also has cimuitry for the battery, contains electrical conrponenls at I-8.375 fl wltich is below tlre flood lreiglrt of 4-8.42 It, Tlre FSAR [Ref. 81 will be i~pdaled to credit i~rstnlled floor dantpers for external ns well as internal flooding. Tlris will reduce the flood height witlrilr tlre CWPH to +7.75 R.

A catch b ~ s i ~ r in tlre platrt yard near the NW corrler of the Unit 2 Faqade was covered with n nietal plate. This plato was rclnoved, and p~acedttral co~rtmls to preve~rt this conditiotr b l n reocct~rri~rg ale beit~g evaluated.

Tire FSAR states that PBNP has liortll and west ilrtercdptor ditcllas outside of tlre plant yard to divert rtrnoff to the lake. The west side irrterceptor ditclr rrllrs bctweea the plant yard and switchynrd, but is obsltr~cted by trewly i~tstalled equiprne~rt n~id is not co~iti~~~ous.

The lrortlr sido ditclr was not found.

The FSAR will be updated to replace tlre nortber~l interceptor ditch witlr the storm drain systern, and A re-evrluation of the drailrage near the wveslem interceptor ditch will be perfor~ned.

a There were several i~rstances of inadequate dl.~bage diblr ~nairrte~rance i~icluditig pmrlially obstrilcted ctllverts atid aolne cases of draillage ditches l~eedillg to be cleared out or re-gmded, Tlra mmi~ltetrat~ce program rlrd supporting doci~n~eaiatio~r will be i~pdated to accrlrately reflect the d~ainnge ditch configuratioa on site nnd elrstlro its filnctloaality, a~ld n work request wvns geaented to clean out the ditohes and culverts w1re1.e the inspection criteri~

were not met.

PBNP is foilnd to be in co~irplia~ice with its flood pmteclion requirements per the ctrrrent site liceasi~rg basis rlpoli colnpletiolr of correclive nclio~is for the above cleficieacies discussed fi~rtlrer i ~ r section 4f,

2. PURPOSE 111 resporrsc to tlre ~~uclenr file1 dn~nage nt tllo R~kuslrisin-Dni-icl~i power plant due to the March 11, 201 1 carllrqunke and st~bseqileltt tst~trm~tri, the NRC established tlre Near Terrn Task Force (NTTF) to coridt~ct n systanntic view of NRC processes a~ld regulaliorrs, ~ n d to nrake recoe~nrontlatiotls to tlre Cotnmission to cInriQ ntid stlelrgtlre~r 1110 ~vgtllnto~y frmmewvork for protection against nati~ral plrenorne~~a.

On Ma~.cIr 12, 2012, the NRC Issued a request for informrtios pttrsl~nnt to Title 10 of the Curlo of Fede~wl Regrrloflorts, Section 50.54 (f) [Ref. 21, 111 Eliclosc~~s 4 o f Itefere~rce 2, tlre NRC requested that licensees 'perfonn flood prultecliolr wnlkdowns usitrg AII NRC-etrdorsd wrlkdown ~rietliodology to identi@ nnd nddress platrt-specific degraded, rrnrco~rfor~ning, or t~nalrnlyzed conditio~rs nlrd cliff-edge eflects tlrrotlglr tho corrective nctiolr prograln (CAP) and ver113) the Page 3 of 19

NTTI: Reco~ti~iieridntion

2.3 (Walkdowns)

Floodilig NextSm Energy Resources - PBNP Nove~iiber 14,2012 NEEObPR-001, Revisio~i 0 deqi~mcy of ~nonitoririg and ~naintenance procedures.' Tlre floodi~rg walkdowns limve been co~npleted and tlie resr~lts are described in this report.

b, Site Dcsc~*lption Point Beacli Units I and 2 are locmtcd ill east-central Wisco~lsia on the west sliore o f Lake Miclrigan, apl~roxl~~iatoly 30 ~niles SE of Greet) Bay. Tlie site is located in the NE colatier of Manito\\voc Cou~lty, Wisco~~sin, and coniprises approxinintely 1260 acres, Vie ground surface at the site is gently ~ulling to flat with elevations varying fro111 5 to 60 A above the lneall level of Lake Micliigmn. Tlie plant reference 0.00 A elevation is 580.2 ft IGLD. In tlie area awi~~rd tlie platit, tlie land sr~rface either slopes fro111 west to erst town~uls the lake or to the nor.tIi and soiltli to divert ri~noflawvay fiwn (lie plant. A Iiigh point just to tlie west of tlie switcliyard preve~its any ri~noff inland o f tlie plnnt froa affecti~ig plaat opelations. [Ref. 81 In relatio~i to the lake, a mqjority of the plnnt gvoilnds are located at tlie 26 A elevntion and are riot tlire~tened by [lie wave rt111-up flood of +8.42 R described in detail ill Sectloll 48, The only exceptio~i to this is the area near tlie CWPH wliere tlie plant draws its circr~lnting water frola tke lake and llns a g n ~ a d floor elevation o f 7 R, 011 the east side of llie plant, the service roads slope down fro111 the 26 A elevation to elevations around 7 fi near die CWPH. h i 1 tlie CWPN, tlie stnlctures next closest to tlie lake nlv the Units 1 and 2 Ti~rbine Buildings (TB) with tlie Control Bilildi~ig (CB) located it1 betrveen tlre TBs. The ground floor elevatio~i of the CB a~id TBs is 8 It, and they 81.e about 100 ft to tlie west of the CWPH.

3. METHODOLOGY The \\valkdow~is were performed in ncco~drnce witli NEI 12-07 (Rev. 0-A), "Guidelines for Performing Verification of Plnnt Flood P~+otectioa Features," dated M&y, 2012 [Ref. I].

Tlris doculnent was endorsed by the NRC os May 31,2012.

Tlie isfot.nimtio~r requested in Reference 2, Enclos~~re 4, under yara&raldi 2 of the 'Requested Infonilation' sectia\\, is provided below, Tlie contellts o f eacli item werc devoloped in accordance wit11 Reference I, Appendix D.

a. Rcql~cstcd I~~fonnrtion Itclrr 2(n) - Design Bnsis Flood Hnarrcls Describe tlie desig bnsis flood liazmrd levelfs) for nll flood-cnusil~ ~neclunisrs. iliclr~dinn u~ui~~idwateg

iunvess, Tliere are two different design basis external flooding I~amrds considered at PBNP. Tlre first is llie flood level tes~lting from a probable ~uaxi~iiurn wvnve ri11i-up fium Lake Miclilgnn, wid tlie other is a combi~ution o f a p~ubnble ~iiaxirnilrn s~rownielt witli a probable tiiaxilnl~ln p~~ocipitmtiotr.

Tlie deterraiaatio~r of tile flood level for tlie probable ~liaxinit~rl~

wvnve run-11p co~iservalively cotnbines the liisto~*icnl liigll lake level of +I

.7 A, a ~liaxi~nr~rii deep water wave nln-up on n verticnl surface of I-6.55 ft, and H wind tide settlp of SO. 17 n for 8 total wave run-up of I-8.42 f l nbove llle plfitrt's referwrce 0.00 ft elevatlorr o f 580.2 A IOLD. Tlie origi~lrl analysis of tlie deep water wave run-~IO wvns perfornied by Sargent & Lr~ndy in Referonce 5. This ntulysis starts by ~alct~lrnti~ig tlie deep wvater wclve heights based t~pon data taken fiwn Reference 4, Howvover, the very sl~allow slope of tlie bcacli out into llie lake at PBNP (I on 100 for the first 1000 fl into the lake and I on 200 for tlie next 4000 fl) causes tliose lnrger deep water waves to break offsllo~e. 'rile ~naxiniu~n wave run-up resr~lts fium esti~nmtiag the prubable maximum secondary wave that wvould reform nAer tlie deep wvater wave llas broken and tlie ~.esulting rial-up on the bench. Tlie lin~ititig case Page 4 of 19

N'ITF Recon~~nendntion 2,3 (Walkdowns): Flooding NextEra Energy Resources - PBNP Noventber 14,20 12 NBE05-PR-001, Revision 0 for PBNP is +6,55 ft of run-up on a vertical structi~re with a period of 8 seconds. In addition lo this wave ru~t-up, wind tide setup is considered for rlre conservative co~lditioris of a concun.ent sustaiued easterly wind of 40 rnpl~ over a fetch lengtlr of 70 r~iiles and average water depth of 465 ft, which produces at1 additional 4-0.17 A, Tlierefore, tlre combination of the run-up, wind tide setup, anti previously recorded 11igh lake level of 4-1.7 ft produces a design basis flood level of +8.42 ft or approxi~nately 8' 5". [Ref. 51 The other design basis external flood threat nt PBNP is a large snowlnelt in tile spring conlbined wit11 sl~stained lreavy winfalls to produce a total of 1400 aci-e-ft of ru~loff on Llie site. This analysis was performed in Referetrce 7. The report states that the atice in 50 years snowrnelt potential (defined as tlre water content of slrow in late March) at the site is 360 acre-fl in each of tlie two drainage areas on site. For the once in 50 years six-hour rainfall expected 011 site, the report gives a value of 31 7 acre-ft in each drainage area.

Therefore, the design basis flood threat fro111 a cornbi~ied snow~rlelt and six-I10ur rainfall is con~crvatively given as 1400 acre-A of runoff, Tliere is 110 n~el~tion of an associated flood l~eigllt for this desigtl basis flood, Other flood causing meclrunisms were considered wlrer~ cleterrni~litig the maximulu flood llrreat ftom tile lake, but were uot foiurd to be tlie botlrldirig cases. Tlie maximum storm surge level was calculated based upon Reference 6. Tlre aualysis arrived at a water rise of 1-4.14 R asst~~ning the passage of a squall line with a pressure jump of 8 ~nillibars and a speed of ~rrove~ne~lt of 65 knots with n shoali~ig fnctor of 3.5. The analysis also states that an additional I ft could be added if wi~~tl velocities arc grentcr tllan or equal to 70 knots.

Rogardless, the stonn surge's maxilnu~n water rise of +5.14 A is bounded by the watcr rise of +6,72 ft res~tlting from the wave actioa.

Seiclies were also considered in tlie vici~lity of PBNP. Most of the data reviewed collcerned seicl~es 011 the southern elid of Lake Micliigan near Chicago. These data itldicated that a record seiclre occurred in 1954 that produced n rise of 2-4 ft ia Clricago harbors. However; this event is not representative of tlle conditions at PBNP because Cllicago is subject to the seiolie's reflection off of the south end of tlie lake, whereas PBNP is located on an open shoreline and is not susceptible to this reflection, Therefore, it was coocluded thnt n seiche 1-2 ft in atnplitude would bound any seiclie ueae PBNP, a~rd tlle deep watel. wave nin-up is still the bounding flood threat from Lake Michigan at PBNP. It slioi~ld be noted that a search of records did not discover ally evidence of a coincident occuwetice of a major seiclie wit11 a major high wave occurrence

[Ref. 81.

Groundwater ingress is not considered as a desig~l basis flooding event due to the high clay conter~t of the soil at PBNP, which inhibits percolation and drainage to L ~ k e Miehignn [Ref, 8).

b. Requested Information Item 2(b) - CLB Protection at~rl Mitigation Fcatures Describe !~rotection and niitigatio~i features that are consiclered in the licensing basis evaluation to protect against external ingress of water i~ito SSCs impotta~lt to safetyl Tl~e external flood licensing basis at PBNP provides for the rlritigntion of design bnsis floods tlrat keeps external ingress of water f'rorn occt~rri~~g in rooms with strtlclures, systems, aud cotnpollents (SSCs) important to safety with the exception of possible water intrt~sion to the service and fire water pump roolns in the CWPH during wave run-up event. The CLB does not specify wllicll plant configt.ations arc considered. Tl~e flood protectioa systems considered in the walkdown also irrdepe~rde~it of the plant configt~ratio~r.

'Tire first situation to consider is tlie design basis rnaxi~nr~nl probable wave run-LIP of 4-8-42 ft from Lake Michigan. Tlrc CLB calls for tile installatioa of temporary concrete jersey barriers to provide a flooding barrier at the CWPH tlrat woi~ld protect equipment in tlie CWPH, TBs, and CB fronl the flood waters up to

+9 ft. These ba~.rie~~s are installed under a site procedure, which planipts tlie irrstallatioli if a ntontlily clieck of tlie L ~ k e Miclriga~~

water level indicates a vali~e of 580.7 fi lGLD or Irigtler. The it~stallation of tlrese barriers is a~iticipatoly and dependent on the u~idisturbed lake level. Since lake level clialige is a slow process, there Page 5 of 19

NTTF Reconrn~eridatiorr 2.3 (Wnlkdowns): Flooding NextE~a Energy Resoiirces - PBNP November 14'20 12 NBEOS-PR-00 I, RcvbioI~ 0 a1.e miany days before tlie barriers must be in place. TJle actual itistallation titne is rni~ch less tliall the required tirne, tlremfore it is not credible tlrat tllere will be itrclernent weather that will prevent tlre installation of tlis barriers wilhin tlie required titne, Tlie barriers are illstalled on both the nortl~ and south sides of the CWPH forebay strilcture as indicated willlin the procedure ia two rows of three barriers each. This moans that 12 barriers are installed aad extend approxinlately 37.5 ft to the north a11d soutli of the CWPH. Tlie CWPH is also protected from direct impact of tlie wave rcm-up by the three foot thick reinforced concrete walls of the forebay strt~cture wliicl~ rise to lleights of +15,4 ft parallel to the shore (fiont) and +I2 ft perpe~~dict~lar to the shore.

Since some water is likely to spill over or th~uugli the jersey barrielms, the storm drains around the CWPH are also credited to provide a relief flow ~ R U I for ally water that rntty begin to collect behind tlie barriers by dninirig it to the lake. Sirlce tlre water that collects belrind the barriers could cl~alleage the doors iuto the CWPH, the CLB further clarifies that the lowest pieces of essential equipment in the CWPH are the service water and fire water purnp motors that are tnot~nted at t9 ft. The fire pumps in the CWPH are designated as augmented quality equipment acid are not safety-related. For this inspection, support equipment necessnry for the operation of tltcse pump rnoton wns also considered, i~loluditig tlie co~~trol panels for both fire punips as well as the battery for the diesel fire pump. It can also be rroted tlrat while not yet explicitly credited for external flooding situations, there are internal flood relief dampers in the floor of the CWPH that prevent water fium building up to ce~tain l~eiglits insitle tire pump lioi~se as a part of the internal floodirtg program.

The CLB does not define a duration for tl~is deslgr~ basis flood, only 1\\18 probable maximum height of the wave run-itp.

The otl~er design basis situation that is considered in tlre CLB is the tnitigatioti of tlie combined rain and saowmelt flood that generates 1400 acreft of runoff. The CLB for this floodi~~g situation in Reference 8 states that the nrtrlrml site dniaage is "adequate to relnove this a~nortllt of water," and a storm drain system as well as drainage interceptor ditclrcs are provided in addition to the natural drainage.

Per Section 2.2 "Topograpliy" of Reference 8, the general site topograplly is credited with diverting surface runoff away from the plant. The wording in Section 2.2 is used as tla ~nairi basis for the CLB that the ground slrould slope either generally from west to east towards the lake or to the north and soutlr to drain 8way from the plant.

Tlie credited stolm drain systen~ handles runoff within the plant protected am. The systetn consists of a inairi drain line on both tlre north and south side of the plant and two s11111Ier drain lines that (Iraia to the north and soutll of tlle CWPH. The drain lines consist of open catcll basins and mdergroa~d piping that enlpty out onto outfalls at the beaclr, Finally, there are also several drainage ditches around the site that provide relief paths for the flood wrters to flow away from the plant. Section 2.5 of Reference 8 states, "An interceptor ditch drainiug to the lake is provided outside the yard on the north and west sides and on the south slde wliere the orlginal ground elevation is above the plant yard!'

In addition to tl~esa main ditches, a small drainage ditch to the aortll of tlie switcliyard and B drainage ditch running along the north plant access road exist and drain dow~i into the northern storm drain line. Tbere are also several ditches along the service roads on the west side of the plant protected alea that drain either to tlie storm drain system or to one of the rnain drninage ditches.

The CLB does not define ti duratioa for this flood and only provides that the amoulrt of r~lnofffronl rain was calc~~lrted based on the once in 50 years six-Lotrr rainfall. It is also tlnclear what lreigl~t the flood waters wot~ld reach because only a give11 volume of runoff was quoted for this design basis flood.

In ~ccor(1ance with PAQ-007 [Ref. 101, exterior walls tllat were subject to groundwater intrt~sio~l were it~clilded as a part of the walkdown scope even dougl~ they are not credited external flood features within the PBNP CLB. Data on the groundwater table deptli taken as a pnrt of the sib's Oroundwater Monitoring Page 6 of 19

NTTF Recolnn~endntion 2.3 (Walkdowns): Floodi~~g NextEra Energy Resources - PBNP Novenlbcr 14,20 12 NEEOS-PR-00 1, Revision 0 Program was used to detelrliine the scope of the walls to be inspected. The water deptlis were taken on the west side of the pla~~t ill !lie Unit 1 aiid 2 Facades on the 6.5 A elevntion. Tlie data intlicated tliat tlie g~uuadwater deptlis fell below the 6.5 fi level by several feet except near the westeni walls. Conlbi~ii~ig this with the information hiat the groi~~idwater lias a gradient towards the enst niearis tl~at the groundwater table is below tlie platit's 8 ft grouncl floor elevation. Therefore, only the walls on the west side of the facades at the 6,s ft level aud tlie Primary Aoxilinry Building (PAB) at the 8 A level, tlie tendon galleries under both uuits' co~ltaiu~nents, and the external walls of tile Residual I-feat Re~noval (RHR) areas on the -5 R and -19 fi elevntions need to be iaspected.

c. Requested Information Item 2(c) - Flood Warning Systems Describe RIIV war~rine svsteliis to detect tlie presence of water i ~ i rooms i~~iporta~~l to safety.

The primaiy flood warning system employed at the site for exterlial flood protection is the periodic check, wliicl~ protnpts a tno~itllly check 011 tlie level of Lake Michigall. If tlie lake level is greater that1 or equal to 580.7 f (2.5 A above nornitlal lake level), tl~a~i

!lie tempora~y barriers that pl.otect the CWPH, TBs, and CB are installed witbin tlic next tllrcc weeks and are to stay installed until the next ~~io~~tlily check falls below the 580.7 I? threshold.

No water level ~nonitoring systems internnl to tlie plant arc credited for ~nitigntion of an external flood. It sl~ol~ld be noted tliat there are high water level switclles in all four RHR puslp cubicles 011 tlie -I9 ft elevation of !lie PAB that iniliste an alarm response procedure for draining the pump cubicles.

(I. Requested Information Item 2(d) - Flood Protection Systcm/Barrier Effectivaness Disci~ss the effective~iess of flood protection svstelns wid exterior. ircorpornted. and temporal?l flood barriers. Discuss how tliese s~stems a~id barriers were evaluated usins. the acceptallce criteria developed as part of Requested l~rfor~natio~~

Item l.I1 [in Etlclosure 4 of the March 12.2012,50.54(f'l letter1 Vis~~al inspectio~ls of !lie exter~lnl flood protection features identified it1 !lie PBNP CLB were perforaied with tlie objective of comparing the observed conditio~~

of the feature to tlie accepta~we criteria as defined in Secliorl 6 of NEl 12-07. This approach provided the b~sis for assessing !lie feature's ability to perfor111 its intended exter~lal flood protection f~~~~ction and identifyiag co~lditior~s warrantitig eritry illlo the CAP.

Observations entered into the CAP and dispositioncd as deficicrit arc discussed in Sectio114f of this report.

With the exceptio~i of features entered into the CAP and deerned deticielit as disci~ssed in section 4f, the walkdowrls fouad lliat the flood protectio~t features meel their applicable acceptnnce criteria.

Tlie following sectiotis detail wlietlier or not tlre acccptaricc critcria wvorc net for the features inspected, and a disc~~ssio~l of the alitigatioti system's effcctivencss:

Teauorarv Coricrete Jersey Barriels l~lstallalior~

Tlie tempornly concrete jersey barriers were itistnlled on the 11ortl1 and soutli sides of tlic CWPH to ensure that they were available, functionnl, and iniplementoblc to provide protectioa up to 4-9 ft as stated it) the PBNP CLB. Tlie reasonable si~nulation for installillg the barriers met the acceptance criteria for s~~ccessfi~lly i~lstalli~ig tlie jersey barriers witlii~i tliree weeks of tlre lake level determination per the site procedure for iristallatio~l and witti llecessnly support equipnient readily nvailable, plavi~ig the feasibility of !Ire operator actions required. I-lowever, the procedure did not identify that the barriers were installed in B.5.b staging areas on either side of the CWPH, so it was deterrninecl that it was not able to be conlpleted ns writter. The associated corrective actions for the i~~stallation procedure are described in sectlo11 4f.

The co~~figumtion of the jcrscy barriers was visl~ally inspected after inslallntion, Tlie barriers did not rnect tlie acceptance criteria for provitling a barrier to +9 ft against the wave action because the

NTTI: Reco~iime~~dntion

2.3 (Walkdowns)

Flooding NextEn Energy Resources - PBNP November 14,2012 NEE05-PR-00 1, Revision 0 jersey barriers did not extend far enoi~gh to tlie nortl~ and soi~tli where tlie site grade reaches +9 ft.

Tlie barriers also sat on uneves groitrid in solne areas cai~sirig uliacceptable gaps uudernenth the barriers to forni. Tlie configoration of the actt~al barrier systcln inspccted upon installation was considered to be ineffective, pending the corrective actions to bc taken detailed ill section 4f.

CWPH Structure and Critical Eai~ipnient Tlie forebny structure of tlie CWPH is credited for protecting tlic CWPH fi.0111 tlie probnble

~naximun~

wave n~s-np. Tl~c external forebay wall parallel to tlie lake was inspected to ensure tliat the barrier liatl adequate Iieigbt, surface cracking was minor, aud no obvious signs of structural degradation were present. Tlie structute niet these acceptance criterin nnd was deemed an effective barrier to the expected wave action.

Tlie CLB also credits the l~eigllt of tlie lowcst critical equipment in tlic CWPH, thc fire and service water pump motors, as -i-9 ft. The lieigllts of tliese no tors and tllcir associated si~ppo~t equipnient were visi~ally inspected to verify the credited heiglit, All of the pump motors were mounted at least

+9 fl, bd tlie control panel and battery for tlie diesel fire pump did 11ot ~neet tlie acceptance criteria. It slioi~ld be noted tllnt tlie fire puolps ie tlie CWPH are considered ailg~nented qi~ality picccs of eqt~ip~ilcnt and are not safety-relnted. Tlie corrective action for ibis situation is detailed in section 4E Storm Dl-ain S~ste~n Tlie storrn drain system on the site is credited for mitigating boll1 the probable ninxitiium wave run-up (otily tlie drains around tlic CWPH) and tlie probable tnaxi~num co~iibined rainfall and snow~nelt (all storrn drains). The acceptance criteria used for tlre inspection was that all tlrains were illstalled per design, cleaned, and ~~nobstri~cted.

Tlie storrn drain systeni is n~ai~itained by a preventative maintenauce (PM) program perfor~iied once every six ~nontlis. A PM is perfor~ned for the CWPH drains that cleans nnd tests tlic storm drains, and another PM inspects a~ld cleans the re~nainder of thc stornl drain systeni. Tlie PM program was decnied to meet the frtnctional requirements of tllese acceptance criteria, a ~ ~ d flle stor111 drains are considered to be achieving their flood protection fi~nction. In addition to the credited PM program established for tlie storrn drains, an extensive irispectioti of the stonn drniii system was condi~cted it1 June of 2010 by AECOM [Ref. 1 I],

which also concluded that "nonc of the structures in the storm drain systeril appeared to shown any significant deterioration," Pipe seg~nents were generally in good condition with snlall atnounts of gravel or dirt on tlie botlo~n of the pipes, wllicll was determined to riot sigriifica~~tly restrict the capnoity of tile pipe. During A visual inspectio~i to ensirre no unexpected conditions existed, one storni (Irain was found to be covered with a ~netnl plate, and tlie corrective action associated with that is detailed in section 4f.

Site Touogrnpli~

Tile nnturnl drainage of tlie site is credited for providing a flow path for tlie generated runoff during tlie probable niaxinit~~ii rain and s~iown~elt.

Tlie acceptance criteria developed were based upon Section 2.2 of the FSAR [Ref. 81, wliicll st~tetl that tlie topography of tlie site either provided n gladient fro111 west to east towards tlie lake or towards tlio north and south nwny fi-o~n tlie phit. The addition of paveillent to tlie site wns not considered to inc~aase tlie i~npeniicability of tlie ground becnusc tlic site all-eady has a higli clay contenl preventing percolntion as stated in Iteference 8. A visual inspection was conducted a~.ot~nd tlie site area to verify this, and ao cliangcs in land use or topograpliy were uoted tliat caused ndvelse ilnpact to drainage. On tlie nortli side, the nddition of tlie Diesel Generntor Building (DGB) nntl Nortll Service Building llave built up sonle areas closcr to tlie lake eli~ninating the west to east flow path, but Illis cllange is supplemented by the storrn drain system, wliicll drains out tlie potential areas of pontling created by tliese cl~nriges and deemed to be Page 8 of 19

N7TF Recornlaendation 2.3 (Walkdowns): Flooding NextEra Energy Resources - PBNP November 14,20 12 NEBO5-PR-001, Revision 0 acceptable. A similar siti~ation exists near the CWPH whe~e secerity llreasures installed created a possible Irindraace for the flow path towards the lake, but tlie possible area of pouding is adequately drai~led by the CWPH storm drains. Otherwise, tlie additional buildings and clianged land use were not found to cause adverse impacts to the site's drainage.

Drrrinaae Ditches The CLB credits interceptor ditches 011 the north, south, and west sides of tlte plant that drain to the lake for providing a flow path for the gerlerated runoff. The acceptance criteria developed for these ditches included confirming their configuration as described in the FSAR [Rec 81 as well as tlre lack of obstructio~is in the ditcli patlrways and culve~ts. The ~011th drainage ditch was foulid config\\~red as described in Reference 8. Tlre westerr] irrterceptor ditch was fotr~id to run between the plant yard and switchyard, but tlie additiotl of new plant equipment created unaccept~ble obstructio~rs in the drainage pathways, and it was not a continuous ditcli. Tlie aortl~ern interceplor ditch was not found doring walkdowns, and tlre ritnoff generated oti the nortll side of the plant area is handled by the storm drain system illstead. Tlre corrective actions associated wit11 the deficiencies for the interceptor ditches on tlre t~orlli and west sides ale detailed in section 4f.

In additloti to the issues with tlie tiortlt and west interceptor ditches, there were several at-ers around the site wltere drainage ditches were not found to be maintained adequately. This includes three drainage culverts on tlie south side of the site that were either partially obstructed or sitb~nerged in pollding. Another dr~illage c111ve1T near the north security gate was also found to be obstriwted. Some drainage ditcl~es lrad buildups of dirt and silt that indicated poor drttitiage flow arrd required upkeep or possible regrading. This pri~narily applied to the draillnge paths along tlre north and south sides of the switchyard. The corrective actions associated wit11 these observations are detailed in section 4f.

Tlie subgrade walls at PBNP are not credited feati~res, but wem inspected in accorda~~ce wit11 PAQ-007 [Ref. 101. The groi~ndwater table atid subgrade walls are inspected in the PBNP Facilities Monitoring Program (FMP), which contains acceptance criteria for i~upection as stringent as those used in Reference 1 and I0 CFR 50.65. This includes co~lfirrni~lg that there are no unacceptable signs of water seepage tllrotlgli the walls, and surface cracking is less than 0.04 in, Therefore, walls already being tracked adequately by the FMP were vist~ally scanned only for ut~expected conditions not previously documented witllin the PMP.

Units 1 nnd 2 Facades Tlie subgrade walls and floors in the Units I R I I ~ 2 Facades were confirmed to be stn~cturally sound with no t~nexpected cracking or water seepage. However, three arens we^: identified where diict banks penetr~titig the walls have partially or fitlly degraded senls by design with open drai~l pans 10 prevent cable submersion. These sliowed signs of water scepage and are poi~rts of prior water intrusion into the facades. However, this is not considered to be a violatio~l of the CLB because tlre fapade walls do not protect safety-related equipment.

U~rits 1 arld 2 Tendon Galleries The walls of the Units I and 2 Tendon Galleries li~ve not been ttncked by the PMP, and during Lspection of tliese walls, several areas of water seepage were found. Tlris observation was noted in the PBNP CAP, wliicl~ determined that tlie leakage rate t1)rougll tlre walls is not errougk to cl~allenge any safety related eqt~ipment. 1Yle tendon gallery walls lyill be tracked in the FMP begin~ring with tlie Fall 2012 Unit 2 r~fi~eling outage.

Page 9 of 19

NTTF Recom~ncudation 2.3 (Walkdowus): Flooding NextErn Energy Resources - PBNP Noveniber 14,2012 NEE05-PR-00 1, Revision 0 Units 1 and 2 RHR Pipeways The U~iits I and 2 RHR Pipeways on tlre -5 ft atid -19 A elevations are liigh 1.adiati011 a~ld liigh contamiuatiotr areas causing thear to be infieqiiently inspected by tlre FMP. During inspections of these areas, signs of groundwater seepage tlirougll tlie walls were found in both Pipeways. On the Unit 1 side, tlre NW corner of the area sllowed signs of water ingress behind the ductwork in tlie cortiel; and previous instances of grou~idwater int~vsion at this point of ent~y have been doci~~nented in the CAP. For tlie U~iit 2 RHR Pipeway, a builditp of eflorescetrce was found underneatll peldrations to tire Uliit 2 Tendoti Oallery. It could not immediately be determined if the water causing this efflorescence originated fiom within tlie tendon gallery or an exter~tal groundwater intrusion. These observations were not considered to be deficiencies by the CAP, citing a prior evalaation of tlie groundwater leakage rates and drainage capacity of the RHR pump cubicles.

Is general, tlre sub~mde walls are considered to be effective in prevetiting groundwater intrusion into the plant based upon tlie adequate sife monitoring program they are included on with the exception of tlie rioted observations above, Tlrese observations will be Iiandled by the PBNP CAP and tracked within the PMP 111 tlie fi~ture.

Overall, PBNP e~nploys a nutnber of different flooding protection fertttres that are available, filnctiontll, and ilnplenietitable respective to their credited flood protectiol~ filnctions upon co~npletion of tlie corrective actions detailed i ~ i section 4L

e. Requested Information Item 2(e) - Implementntion of Wnlkdo~vn Process Present ir~forrnation related to tlie imple~nentation of the walkdown process (e.~.. details of select-walkdown tea111 and procedures) using the documentation template disc~lssed in Requested Infor~nntiorl Item 1,i fill Enclosu~~e 4 of the Marc11 12. 2012. 50.54(fl letterl. i~lclrtdia~

actions taken in resuonse to the peer review.

Consistent with Section 5.3 of NEl 12-07, wrtlkdown teams consisted of at le~st hvo trained individlrals with a complementary set of skills, The walkdown tealti consisted of tlaee rnechanical engineers from ENERCON and three rnecl~~nical engineers from tlre site. h c h walkdowa was perforriled by at least twa members of the walkdown team. The membe~~s of the walkdowns tea111 had varying levels of experic~rce wit11 plant iiiodifications, engineering walkdowns, and prior flooding work boll1 at PBNP and other sites. In addition, a civil liydra~~lic engineer provided expertise during the develap~nellt of tlie walkdow~i package for surfice drainage features.

Per Sectiorr 5.3 of NEI 12-07, personnel selected to perform walkdown insyeotfori activities were experienced and kno\\vledgeable of tlie site current lice~rsing basis. Personnel were experienced or trained to perform visilal inspections of SSCs and met tlre knowledge reqrtireme~its of Appendix C of NEI 12-07, All team membets that perfonlied the vist~al inspectio~rs were trailred to and knowledgenble of tlre below informntiorr:

NANTEL lesson on Oet~eric Flood Protection Walkdowns Specific PBNP licorrsing basis ~natcrial NTTF recommendation 2.3-Flooding and tlie NRC lelter dated Mawll 12,20 12 [Ref, 21 NEI 12-07, Revision 0-A [Ref. I]

ENERCON pe~ronnel weis supported by site and craft perso~~nel cluriog tlie walkdow~r wlro were 1101 scqui~.ed to meet the above requi~rnents. These pessonnel were used because of their familiarity with plant Page 10 of 19

NTTF Recom~nendation 2.3 (Walkdowns): Flooding NextEra Energy Resources - PBNP Noveniber 14,2012 NEE05-Pk001, Revision 0 SSC's and protective measures. Generally, these personnel inet the knowledge require~nents but did not undergo the ~~quircd training. A pre-job brief was perfoiuned prior to conducting the waikdowns usi~rg pla~~t lit~~nan performa~~ce procedures and was tailored to the walkdow~~

task, Eacli walkdown performed a specified inspecti011 to assess the capability of the item to perfonn its requised fnnction. All walkdow~l results were docu~nented in accordance wit11 tlie recornmendations of Section 7 of NEI 12-07 and usi~ig tlie walkdown record form template in Appendix B of NEl 12-07.

f. Requated Information Item 2(f) - Findings and Corrective Actions TakenIPlanned Results of tlie wvalkdown inclirdiap kev fi~iditi~s ar~d identified deuraded. non-conforming, or unnnalvzed conditions. lticl~~de a detailed descri~tiotl of the actions taken or nlant~ed to address tllese conditio~~s usin8 hpuidance In Reatdatorv bsues sum mar^ 2005-20. Rev I. Revision to NRC lnspectioti Manual Part 9900 Technical Ciuidance, "Ooerabilitv Conditio~is Adverse to Oaality or Safetv." i~~clttdinn enter in^ the co~~dition fn the corrcctlve action pronrm All observatio~ls made during the walkdowns that were riot im~nedintely judged as acceptable were entered into the CAP to be dispositioned by the site. The following details {lie observations that were determined to 3:

Slatus Being tracked usder corrective action program Page 11 of 19 planned in accordance witli Reference Dispositio~~

Due to the insufflcie~~t length of the jersey barrier configuration and the possibly unacceptable gaps in between barriers, this situation was altered into the CAP and determined to be a deficiency.

The corrective actions (CAs) y la~lned iuclude:

1) Adding four tnore jersey barriers to (lie ct~rrent con figtwlio~l to achieve the needed flood pmlsolioll

2) Pouri~~g a new concrete pad to provide tlie jersey barriers with an even surface to be installed upon and eli~nirlate gaps t~nder~~eatll the barriers There is no operability issue because the current lake level is low e~iougll that the probable maximum run-up woi~ld not affect pla~it equip~nent, be deficie~icies and their respective Description oTDeficiency The configuration of the jersey barriers was found to be inadequate.

Field merrs~~retnents indicated that on both sides of the CWPH, the barriers did riot extend far enotrgll north and south to provide flood pmtectiot~ up to the design flood height of 4-8.42 R In the currelit configuration, the lerlgtli of the tliree-barrier-long artallgemeat 011 either side Is approxinlately 37.5 ft. On the nortll side, it was foti~~d that tlie barriers need to extend anotlier I IS inches to protect ngai~~st the flood level, and on tlie soutli side, the barriers need to extend another 122 i11cl1es. In addition, the rigid coricrete bmrriers do not sit flush on the tineven groia~ci in the vicinity of the foreb~y, and some gttps exist between tlie ground and the barriers. Fisally, on the sides of tlie barriers, there are nietal loop$

that are used for anchoring the barriers together, and these loops cause gaps of approximately 3 inches to exist in betweeen tlie barriers.

corrective aotious Fen tare Category Ts~npornry Passive

NTTF Reconlmendation 2.3 (Walkdowns): Flooding NextEra Energy Resot~rces - PBNP November 14,2012 NEE05-PR-00 1, Revisio~lO Page 12 of 19 Sfattls Being tracked uuder corrective actiotr 1)1agram Being tracked under action program Descrpfion of Deficiency The reasonable simnuiation for the iastallation of the barriers slio\\ved the procedure cannot be execlited as written. The jersey barriers are installed in a location on either side of the CWPH that is marked as a B.5.b staging areti, and no provisions are made to ensure B.5,b requiremetits are rnet wlt i lo tile barriers are installed. Also, the entry into the CAP suggests that the riecessaly support equipment (forklifts, etc,), site support (security coverage), and a periodic clreok of the staging conditiorl of the barriers be added to further ellha~lcc the procedure.

Wlle~l the heights of the fire and service water pump ll~otors were obtained within the CWPH, a deficiency was fot~nd relating to the diesel fire pump. The diesel fire pump's colltrol pallel C-6 1 and battery D-600 did not meet the credited height of +9 ft. The termiaatioim of the batte~y were mensured to be +8,5 ft off of the floor, just above the flood height of

+8,42 ft, and the electrical panel that contained C-G1 atid oil-ortitry for D-600 had electrical co~npolletlts at

+8.375 R off of the floor, which is below the flood height. It should be noted the fire pump is augcnerited quality equipment, not safety-related.

Ii%atirro Ca tego~y TetnporflrJ' passive lllcorp~rated Disposition Tliese observations were deter.rniaed to be a deficialcy, and a CA was ge~ierated to write a procednre change to eli~ninate the procedure's inadequacies and incorporate tlre suggested enhaacements.

Thro is no operability issue because the current fake level is low enough that tlre probable ~naxinlurn rial-lip would not affect platlt equipment, and the jersey barriers would not be needed.

This observation was deteimined to be a deficiency, and !lie plarlned CA is t~ credit the CWPH floor dainpers for extenlal as welt as internal flooding. This will reduce the flood lieiglit to 4-7.75 A fro111

+8,42 ft based up011 tile existing capacity for flood relief in the CWPH, Tllere is no ftttlctio~lrlity issue because the current lake level is low enongh that the probable niaximum run-up would rlot affect plant equipmalt. These are not Tecl~uionl Specificatio~i equiptnent.

NTTF Recon~mendmtion 2.3 (Walkdowns): Floodi~~g NextEm Energy Resources - PBNP Noveniber 14,2012 NEEO5-PK-001, Revisinn 0 Page 13 of 19 Status Beillg tricked t~nder corrective actiotl program Being tracked under corrective action Iwogram Description of Dof'iclcncy It was observed that the catch basin it1 the plant yard near the NW corner of tlie Unit 2 fapade was covered with a metal plate, prevetiti~lg it from accotnplislii~lg its flood protection filnction.

During tlie walkdow~~

of tlie drainage ditches, it was discovered tllat the i~iterceptor ditches on the ~iorlli and west side of the plant [Ref. 8) were eitlier not folttld or inadequate. Tlre west side interceptor ditch that runs between the plant yard and switcllyard on either side of tlie 13.8 kV Buildi~ig was dearled illadequate' On the south side of 13.8 kV Building, the ditcli is obstructed by u new (~a~isformer acid propalie lank. On tlie nortli side, tlic ditcli is riot well defined ntrd nlso has a liew transformer and capacitor bank blockilig its path, For the north interceptor ditch, 110 apparent ditch was found tliat drained to tlie lake.

All of the drainage fotl~~d in or tlear tile plant yard OII the riortli side feeds dow~i to the iio~tli storm drwin line.

Fcature Cntegory hicorporated Passive lticorporated Passive Disposition Tliis observation was detemlined to be a deficic~lcy, and the plate has bee11 re~noved. A CA was created to update tlie model work orders (MWOs) for tlry firel storage to i~iclude a step to reemove ground supporl plates after co~npletio~i of tlie campaign..

No safety significant plant equipment is clialle~iged because there are no ide~rtified intrusio~r paths into tlic fapade, Diesel Gelieralor Building, and Le PAB above grade level.

Tliis situation was deterinitled to be a deficierlcy by tlie CAP and the planned CAs inclide:

1) Updating PSAR to replace the north interceptor ditcli with the storrl~ drain system on tlie north side.

Tliis is at1 equivalent change that was never incorporated after tlie co~istrt~ctio~~

of the DOB.

2) Perfor~iiing a re-evaluation of tlie drainage 011 ttie west side of tlie pln~it yard around tlie ditch, taking illto consideratioa tlie added cquip~nent that Itas obstructed the ditcli.

No snfety significasl platit equipmalt is cl~alle~~ged because them fire no identified intrusion paths into the fapade, Diesel Generator Building, slid the PAB above grade level.

NITF Reco~ri~~~endatioti

2.3 (Walkdowns)

Flooding NextEra Energy Resources - PDNP Nove~trber 14,2012 NEE05-PR-00 1, Revision 0 Dcsc~*iptloa of Doficlercy Feature Cat@gory Disposltlotr Stnttts Tlie niai~tte~iarice of drainage ditches Tltese observntio~is were and culverts wvas not found to be entered illto tlre CAP acid adequate after several drainage patlis determined to be a deflcicncy.

were fou~td to be pa~lially obstri~ctcd.

Tlie drainage ditcli Tliis iticluded tliree drainage culverts

~naititetiance will be updated to o r tlie soetli side o f tlre site tliat were address tlre shortconri~igs in citlier parlially obstructed or tlie current PM program. In Beitig additio~i, tlre plant drmwing tracked sub'nergd in pO'lding' lncorpornted used to guide the PMs will be drai~iage culvert near tlre ~iortlr wider security gate was nlso foit~rd to be Passive updated to more accc~wtely corrective obstri~cted. Sonie d~.aiiiage clitclies reflect the co~iflgt~ration o f the action lrad buildups of did mod sill tliat surface drminage features at the proyrnlii indicated poor dsmiaage flow a~id site. No safety sig~l;ificatil plant required clenri~ig or possible eqt~ipnreat is challe~iged re-grading. Tliis primarily applied to becoi~se tlrere nre no idetrtified the drmi~iap patlis a101ig t l i ~

~iortlr intntsion patlts into tire faqnde, and sot~tlr sides o f tlie switcliyard.

Diesel Generator Buildi~ig, and the PAB above grade level.

PBNP has tio flood protection fertttrws designated as restricted access or inaccessible.

g. Rcquestod I n f o r m n t i o ~ ~

Item 2(g) - Cliff -Edge Effects nnd Av~flnble Pltysicnl Mnrg%

pocu~netlt aliv cliff-ed~e effects idetrtified arid the associated basis. lrldicate tliose tlrat were entered into the corrective mctio~l proitrnln. Also inclt~de a detailed descriptiort o f die actio~is taken or plttn~red to address tlrese effects, hi accordance with NEI 12-07, Available Pltysicml Margins linve been collected and doct~~~re~ited ill tlre Walkdow~l Record fornr (Appendix B). The g~~idnt~ce provided ill FAQ-006 [Ref. 9) was also followed. Tlris ittforri~atiotl will be used ill tlie flood liaznd reevalt~ations performed in response to ltoni 2.1: Flooding in tlre 50.54(f) letter [Ref. 21.

Ir, Requested Infolm~mtion I t c n ~

2(11) - PI~nnedlNowly-lnstrllecl Flood P~~otection Enl~mcetnents Describe w oil-or acwlv ltrstnlled flood umtcction svste~iis or flood mitiaatiotr incasttres j~rcludhn flood barriers (hat A~rtlrer e~ilim~rce tlie flood protectios, ldetrtifv ~esults m~rd ally sttbseque~rt actiotg jnke~l in resuorise to the Deer ~*evie\\v, Curt~~ttly, tliere NI~! no plrn~red or aewly installed flood protectioa eriha~lce~r~ents or flood lrlitigatioti trieRsltres nt PBNP, Tllere were no cltaitges to tlte wvalkdown process rs descsibecl ill Section 7 or l l ~ e walkdowi~ record for111 111 Apperidix S o f Refet.etice I.

5, CONCLUSIONS Walkdowtis were performed is rccosd~~rce witll NEI 12-07 (Rev. 0-A), "Guidelines for PerFor~ni~ig Verificalio~r o f Plant Flood Protection Features," dated May, 2012 [Ref. I]. miis doct~rne~rt was eiidossed by

[lie NRC on Mny 31, 2012. PBNP Units I & 2 co~iflgtrr~tio~r and procedures were co~npmred to the flood Page 14 of 19

Nm'F Recomaietldntion 2.3 (Walkdowns): Flooding NexlBra Energy Resources - PBNP Novenibcr 14,20 12 NEE05-PR-00 I, Revision 0 protection features credited in the curreut licetlsi~tg basis docu~neots for external floodirlg events.

Site-specific features credited far protection and mitigatiolr agni~tst cxtelaal flooding events were idenlified and evaluated. The results of the inspections are si~lntnarized below.

Reasonable Simulations Tlie reasonable silnulation of tllc instnllatio~i of the jersey bawiers did not raise mly concerns over completion of time setlsilive nctiorls but did identify sonle sl~ortcomings in the procedure concerniog tlle collflict with B'5.b staging requiremeats and otller stiggestetl e~ihancemenis that are beirig ndded, Tliese have been entered into the PBNP CAP.

Insvection Deficiencies Tlie flooding walkdowus verjfied that pctmanent structures, systcms, co~nponcr\\ts (SSCs), tempora~y flood mitigation barriers, and the procedures needed lo install atid or opel~te tlieni during a flood are acceptable and capable of perfonling their design fitnctiot~ as credited in the current liceasiug basis (CLB) with these cxcey)tions.

The jersey barrier co~lfigi~ratio~~

was fouttd to be ir~sl~fficierlt in letigtll to the ilorllt and sot~tll of tile CWPT-I to provide protection to 3-9 fi.

The procedure for the iastallation of tlle jersey barriers did not provide provisio~is for the fact that the jersey barriers are itistalled in B.5,b staging areas on either side of die CWPH, r Tlie control panel and battery for tlic diesel fire pump in tlie CWPH was below tlie flood height.

A catcll basil1 jn the plant yard iiear tlie NW corller of the Unit 2 Fagado was found to be covered with a metal plate.

Tlie ool-th and west ii~terceptor ditches called out in Refere~lce 8 were either not found (north interceptor) or i~iaclequate (west interceptor).

Several drainage culverts and ditcllcs wore found to be pastially obstructed, Cossective Actiolts Tile following CAs were taken in response to the above identified deficiencies:

Additional jersey barriers will be acquired to extend the lel~gtli of the barrier configuration, and n coucrete pad will bc po~~red to address potetllially unacceptable gaps in tile coafigumtiotl, A procedure clla~~ge will be cornpieled to address the inadequacies in tile site procedure for jersey bari~ier. installation, lustalled floor dampers in the CWPI-I will be credited for external ns well ns inlerual floodilig to reduce the flood height in the CWPH Lo 7.75 fi.

Tlte metal plate was removetl from tlie catch basill, a~id the addition of procednral controls to preverit fi~tl~re obstri~ctions is being reviewed.

Tile PSAR will be updated to replace the nortl~ern interceptor tlitcli wit11 tile stow1 drain system, and a re-evaluation of the drainage laear the westeln interceptor ditch will be perfosmed.

Both the mainta~ance progrn~ll for tile drainago dilclles acid the plant drawing used to guide the PMs will be t~pdated.

Newlv installed and ~lalllied flood !>rotection ci~bancements

?'here are no tiewly iitstalled or planned flood protectio~l enha~~cenlents at PBNP, Page 15 of 19

NTTF Recommendation 2.3 (Walkdowns): Flooding NextEra Energy Resources - PBNP November 14,2012 NEE05-PR-001, Revision 0

6. REFERENCES

1. Nuclear Energy Institute (NEI), Report 12-07 [Rev 0-A]. Guidelines for Performing VeriJication Walkdowns of Plant Protection Feattrres. May 2012 [NRC endorsed May 31,2012; updated and re-issued June 18,20121.

2. U.S. Nuclear Regulatory Commission. Letter to Licensees. Request for Information Pursuant to Title 10 of the Code of Federal Regulations 50.54fl Regarding Recommendations 2.1, 2.3, and 9.3 of the Near Term Task Force Review of Insightsfiom the Ftrktrshima Dai-ichi Accident. March 12,2012.

3. U.S. Nuclear Regulatory Commission. Operability Determinations & Fzrnctionality Assessments for Resolution of Degraded or Nonconforming Conditions Adverse to Quality or Safety. NRC Inspection Manual. Part 9900: Technical Guidance. Regulatory Issues Summary 2005-20, Revisions 1.

September 26,2005.

4. Technical Memorandum No. 36, Beach Erosion Board, Office of the Chief of Engineers, Department of the Army.

5. "Maximum Deep Water Waves & Beach Run-up at Point Beach," Sargent & Lundy, 1967

6. "The Prediction of Surges in the Southern Basin of Lake Michigan, Part I, The Dynamical Basis for Prediction", G.W. Platzman, 1965

7. "Preliminary Hydrologic and Hydraulic Studies for Nuclear Power Plant Site Selection," Harza Engineering Company, 1966.

8. Point Beach Units 1 & 2 Updated Final Safety Analysis Report, Chapter 2 "Site and Environment."

9. FAQ-006, Inquiry Form-NRC Submittal, Revision 4, Applicable Features for Quantifying APM, September 13,2012.

10. FAQ-007, Inqui~y Form-NRC Submittal, Revision 0, Inspection of Exterior Walls, August 1,2012.

11. AECOM Technical Services, Inc. "Final Report: Drainage System Inspection; Point Beach Nuclear Plant; Two Rivers, Wisconsin." June 2010.

Page 16 of 19

NTTP Reco~nlrre~idatio~r

2.3 (Wnlkdowns)

Flooding NextEru Energy Resoilrccs - PBNP November 14.20 12 NEE05-PR-001, Revision 0 Attael~nre~tt 1: FAQ-006 [Ref. 91

4. TOPIC; AppUcnblc Fentures for Qannti$Iag APM Soilme docttment:

NEI 12-07 Section:

3.13 & 5.8

p. DESCRIPTIOlyi Sections 3.13 nlrd 5.8 provide a dofinition, description, and exa~nples for Available Plrysical Margin (APM). 111 Section 3.13, APM is defl~ied as "the differe~rce between licensing basis flood lleigllt and tlre flood height at wlriclr water co111d affect nn SSC ilnportarrt to safety". This ieqrli~y is inte~rded to clarify

!Ire latter part o f tl~is defl~rition, co~rsidering tlrat tl~at some featrlres will not hnve a clearly defined exceedance heigllt.

p, RESOLUTIONI (Include ndditional pages if necessary. Total pages:

2

)

Inquiry number:OOb Priority:

H Sections 3.13 m d 5,8 provide a definition, description, and oxa~nples for Availnblo Plrysicsl Margin (APM). 111 Section 3.13, APM is defined as 'Yhe differcnco between licensiag basis flood lreight and tlre flood Ire ant to safety". The latter (gnderli~~ed) pert o f the definition can be interpreted as the height nt which the flood protectiorr capnbllity of n feature is exceeded.

For some features, the exceeda~lce heigllt cnn be olenrly defi~~ed (0.g. flood wvnlls, lovoes, dikes, cofferdams, flood gntes, tlre elevntio~l o f unsealed pendrntions or otbr openilrgs, etc.), For other features (e,g. sad, plug, or water-tight door pressrrre rntil~gs, pilnlllp flow mtes, etc,), 111% sxceedatlce I~eigla cannot be clearly defined witlroirt porforrlri~ig na ellgineeri~rg nnalysis tllnt is beyo~ld tlre scope o f the flooding rvalkdow~v. As a restllt, it is nppropriate to record APM as a si~nple meast~remc~it o f trelglrt difference, Irowvever additional co~isiderations apply.

Tlreie is a concern tllat recording largo APM on tile Walkdowv~r Record Forin could be ~liislending if tlle APM is i~rterpreted as ~nargia tlrnt is avnilnble for ndditio~inl flood protection witho~~t fi~rtller evnl~tation.

For exa~nple, for a flood protection wall tl~at 1s 10-R lriglr and tlro CLB water Ileiglrt is 9.5-R,,

it is reasonable to stnte tlrat tlre APM is 6-inclles for the wall. However, if tlre previolls wall is now 20-0 lrigll and CLB rvnter lroigllt is still 9.5-lt, it CRIIIIO~

be stated tl~nt tlrc wall's APM is 10.5-ft based 011 engineering judgment lon no, In order to verify n Inrge APM that is not already defined fr tlie existing dosig~r doctnnents, nn nnalysis woulcl have to be perforn~ed to evalunte tlie effect o f the ~dditional flood lrefglrt 011 wall lords and prwsstllwe retention capbility for any associated pene!ration SB~IS, AS a regi~lt, tlre rnalrner in wbioh na APM sfrould be ~ecolded oa tlie Wnlkdownl Record for111 depends r~pon whetber the APM is cotrside~~cd lnrgo (nrr i~rtorprctntiotr o f rvl~nt constibtos n "lnrgo" APM is nt tlro discmtion o f tlro utility).

Vie followi~rg gi~idatrce applies, For wnllrclow~is tlini hnve rot yet been pcrfornrccl anrllor tloc~~~rcr~tedr Recording APMs on tlre Wnlkdown Record Slreet as a difference in lreigllt is n reasonable statenlent of the nvnilnble ~lrargitr baarl olr e~lgineering judg~neat a111ess tlie APM is large. For APMs, llrlae options are avaitable: (I) recold a s~ualler, but defensible, APM value based Page 17 of 19

N'lTF Reconrmendation 2.3 (Walkdowns): Flooding NextEra Eneigy Resources - PBNP November 14,20 12 NEE05-PI<--001, Revision 0 otl engineering judgment with a co~~respoudi~ig note in the "com~~teats" section; (2) record no value for the APM wit11 a corresponding tlotc in the "comme~lts" scctioti that an engineering allalysis is necessary to determine tlie maxirnum APM tlle wall can withstaod before a firl~ctio~~al failurc; or (3) referei~ce tile existing PSAR section or desigcl documcnt that suppo~ts tlie APM.

Nole that tliis 11otatioi1 should be made in the response to QI 1, 423, or 427 of tlie Walkdowli Record Forin, ns applicable, For wnlltdolvns that liave been completed:

Recog~lizi~ig that it is not resource effective to revise completed paperwork, it is not necessaly to cl~atige tlte way the APM was recordcd in co~npleled portions of tlrc Welkdowvn Record Fornl. 111 tliese cases, APMs that have been recorded as siiliple measurements of height differences are acceptable as long as tlle APM determination process did ~iot resull in overlooking some pote~~tial margins, as defined by the site per Sectio~i 5.8 of NEl 12-07.

For Wnllcdowa Reports:

lt~dicnte it1 the walkdow~~

report if ally APM information was recorded before the large APM approach described in this PAQ was developed.

Notes:

1. Typically, the CLB for the site will indicate what the probable maximum flood level is & tho level to whicll the SSC i~nportallt lo safety is protected, If the recorded APM exceeds tlle diffetencc between these two values at~d tlie rnargin is to be credited for additio~ial flood proleclioil, the margin must be justified by one of the followilig inethods:

R.

Doci~liie~~ted application of ~.easonable atld i~lclepe~~de~~tly verified engineering judgme~lt

b. Perfolmauce of ricw cngi~leeritlg allalysis

c. Reference to at) existing docurnent or atlalysis that soppoi-ts tile higher protection level Revision: 4 Date: 9/13/12 E. NRC Ravielv:

Not Necessary Necessary X

Explanation:

P. Industry An13roval:

Doct~a~etitation Method:

Sent 13.2012 lneetitw Date:_

G. NRC Accentnnce:

Interpretatiott X

Agenoy Position Documcnt~tion Method:

Sept 13,20 I2 ineetitip D a t e l Page 18 of 19

NTTF Recornnlendation 2.3 (Walkdowns): FIooditrg NextEra Energy Resources - PBNP November 14,20 12 NEEOS-PR-00 I, Revision 0 : FAQ-007 [Ref. 101 A. TOPIC:

l~~spectioti of exterior walls Source doctrnent:

NEI 12-07 Sectioe:

5.5.2 B. DWCRIPTIONr We liave a wet site where the SSCs are licensed to flood and the core is protected t~siny mitigating actions. Some of tlie bdldings have safety-related equipment below grade and below groundwater levels.

The building's concrete walls keep groundwater from altering ll~e str~rnture but tlierc is no rnention of the walls being credited flood or grou~ldwater protmtion featl~res in the CLB. If the walls A I I ~ any associated penetrntioll seals are not credited in the CLB as providing protection (against surface water or groaedwater flooding), do they need to be i~~cluded in the walkdown scope?

On tlre otller krul, if the walls auld associated seals are performing r flood protection fi~nction, specif'icnlly for grol~lldwater ingrcss, even tlloitgli the CLB for floodi~lg is silent on it, sl~oluld a visl~al observatioil of the walls be peufor~ned?

C. Initiator; ne:

J Bellini Pllorre: (6 10) 877-6022 pate:

713 111 2 E-Mail: joe, bellini@nmec.com J). RESOLUTION; (lncltde additional pnges if necessary. Total pages:

I

)

Inquiuy number:D07 Priority:

H Ally exterior wall (above or below grade) protectillg spncc credited as dry in tllc CLB froln groutldwater or surface water flooding shortld be incli~ded in the walkdown scope, even if the exterior walls are 11ot explicitly mentioned in the CLB. Tlre inspection of the walls slio~rld also note degtading or l~oncollfownjng coriditions for associated penet~wtio~is, seals, eto., altlloi~glr the penetrations/seals tlletnselves do not need to be listed as separate fentures, wit11 separate walkdow~l record forms, ur~less individually credited In the CLB. Tlia inspection applies to portio~ls of the walls below design basis flood and/or grotindwater levels.

Note that Available Physical Margin sl~ould be obtained to the lowost u~sealed, unqualified and or inspected sealed penetration above tlre design basis water level.

Revision: 0 Date:

8/1/2012 E. NRC Review; Not Necessary X Necessary Explanation:

F. lndustw Annroval:

Docuii~entation Method:

Dnte: