ML16272A220

Oconee, Units 1, 2, and 3, Enclosure 1: Flood Walkdown Report (NRC 50.54(f) NTTF Recommendation 2.3), Dated November 27, 2012 (Redacted)

ML16272A220
Person / Time
Site:	Oconee
Issue date:	11/27/2012
From:	Duke Energy Carolinas
To:	Office of Nuclear Reactor Regulation
Shared Package
ML16070A295	List: ML16070A284 ML16070A287 ML16070A288 ML16070A290 ML16272A216 ML16272A217 ML16272A218 ML16272A220 ONS-2015-028, Supplemental Information Re NRC 2008 and 2012 Request for Information Pursuant to 10 CFR 50.54(f) Pertaining to External Flooding, Dated March 6, 2015 (Redacted)
References
FOIA/PA-2016-0071
Download: ML16272A220 (30)

Text

ML1233801 12Oconee's Flood Walk-down Information Requested byNRC's March 12, 2012, I0CFR 50.54(f)

LetterNovember 27, 2012.. ....- ... .. 3.-.;;3;V~'

....... ...... .nJLlBI&iVIU d51 qUFIii

= --i.v .... ..... )Enclosure 1Flood Walkdown Report(NRC 50.5.4 (f) NTTF Recommendation 2.3)

Flood Walkdown Report -NRC 50.54 (1) NTTF Recommendation 2.3TABLE OF CONTENTS1.0 PURPOSE..................

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32.0 DESIGN M ETHOD/ANALYTICAL METHOD .......,....................................

...... 33.0 SUMMARY IN FORM~AI-ION....................................................................

44.0 ASSUMPTIONS

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....... ...... .. .....45.0 TECHNICAL PRESENTATION.

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45.1. CURRENT LICENSING BASIS (CLB) FLOOD SCENARIOS.........,.......................

45.1.1 UFSAR Based Flooding.,,..

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45J.1.. Probable Maximum PeclpitatlOn...

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45.1. 1.2. Keowee Reservoir Retention-,.............,..................*

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5.1.1.3 5SF Flood Protect/on

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.....6..5.1.2 Safety Evaluation Based Flooding (Pending, NON UFSAR) ....................

,..751.2.1 Jocassee Sunny Day Failure -Safety Evaluation (SE) .............

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,...,75.2 Flood Mitigating Features and Their Effectiveness......................

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95.2.1 PMP Protection Features

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...,.... 105.2.2 Keowee Reservoir Retention 125.2.3 SSF Flood Protection Features

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135.2.4 CAL Intedim Compensatory Measure (1CM) Features

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.. ....,,. ..... 135.2.5 Other Features

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.185.12.6 Flood Warning systems.......................,............,................

. .. .......195.3 DESCRIPTION OF WALKDOWN PROCESS AND ACCEPTANCE CRITERIA,..

........195.4 RESULTS OF WALKDOWNS

..,...... ... ........,........,.............,..............,...

216.0 ComplianCe with NEI 12-07, Appendix D .....,..................

.... ....... 24.Page 2 Flood Walkdown Report -NRC 50.54 (f) NTTF Recommendation 2.31.0 PURPOSEThis report documents the results of a Flood Design Basis Walkdown performed to provideinformation to the United States Nuclear Regulatory Commission (NRC) as requested by itsletter dated March 12, 2012.

Background:

In response to the events at Fukushima Dai-ichi due to an earthquake andsubsequent

tsunami, the NRC issued an information request on Marchl 12, 2012, in accordance with Title 10 of the Code of Federal Regulations, Section 50.54(f).

Enclosure 4 of the 50.54(f)letter is directed toward addressing the Near Term Task Force (NTTF) Recommendation 2.3 forFlooding and requested the results of a flooding design basis walkdown.

The NRC subsequently endorsed the guidance

document, NEI 12-07 (Rev. 0-A), as a satisfactory approach to providing this information.

This report provides the information requested by the 50.54(f) letter asdescribed in NE! 12-07. This report is based on the current External Flood Licensing Basis andthe features that Oconee Nuclear Station (ONS) credits for mitigation of an external flood (as ofSeptember 2012). The SSC's that are further discussed in this report range from QA-1 to NON-QA. The walkdown findings were documented as an ONS calculation, which constitutes aretrievable location for the NTTF 2.3 Flood Walkdown Report and Walkdown Package.2.0 DESIGN METHOD/ANALYTICAL METHODThe 10 CFR 50.54(f) letter was issued in the course of implementing the lessons learned fromthe accident at the Fukushima Dai-ichi nuclear facility.

The NRC accepted NEI 12-07 as aguideline document created by the Nuclear Energy Institute (NEI), which describes a process forperforming the requested work. The following is an excerpt from the NRC'S acceptance letter."The NRC staff confirmed that the guidance directs the licensee to perform the walkdowns ina manmer that will address the Requested Information items 1l.a through 1 .j in the 10 CFR50.54(f) letter. Additionally, the NRC staff finds that Appendix D, "Walkdown Report,"'

ofNEI 12-07 delineates the appropriate information to be submitted in response to Requested Information items 2.a through 2.h of the 50.54(f) letter.As described above, the NRC staff has reviewed the guidance contained in NEI 12-07 andfinds that performance and reporting of flooding protection walkdowns in accordance withthis document would be responsive to the 10 CFR 50.54(f) letter.'"

ONS took no exceptions to the NEI 12-07 guidelines and implemented the methods that wererecommended for completing the walkdowns.

The NE! 12-07 document was found to beacceptable as a walkdown procedure and was utilized by Oconee in the performance of thewalkdown process.

No exceptions were taken to the NEI 12-07 walkdown process.Accordingly, the Walkdown forms in Appendix B of NEL 12-07 were used to perform thewalkdowns, including a peer review required by the forms.The technical detail contained in this report is derived from referenced information contained inthe calculation written to document the walkdown findings.

Page 3 Flood Walkdown Report -NRC 50.54 (f) NTTF Recommendation 2.3CZNT.JNJ ZEZU~IIT EJTEIrClTZ.

3.0 SUMMARY INFORMATION The requested Flood walkdowns required ONS to inspect all flood mitigation features andprocedures that make- up the current licensing basis. The walkdowns incorporated a thoroughreview of all features, procedures, preventive maintenance (PM) programs, and early warningdetection systems.

The findings support that all mitigation and protection features are expectedto successfully perform their design basis function.

Minor issues were discovered throughout thewvalkdown process and these issues have been captured in the plant Corrective Action Program(Problem Identification Program -PIP). None of the issues challenge Oconee's ability tomaintain the safety condition of the Nuclear Station.One deficiency, as defined by NE! 12-07, was found related to digital readouts of the voltmeters at the Keowee Spiliway.

This issue has been captured in PIP and does not negatively affect theoperability of the Keowee Spiliway.

The walkdown effort was performed, and this report is in full compliance with NEI 12-07. Allinspection requirements were met and no exceptions were taken to the NRC approved processlaid out in NEI 12-07.4.0 ASSUMPTIONS There were no assumptions used in the walkdown process.

Every feature was either walkeddown specifically for the NTTF 2.3 Flood Walkdown in November of 2012, or within the past-year for various other reasons.5.0 TECHNICAL PRESENTATION Thiis portion of the report is provided to describe the current, as Of November 2012, ExternalFlood Licensing Basis and the features that ONS credits in the mitigation of an external flood.5.1 CURRENT LICENSING BASIS (CLB) FLOOD SCENARIOS 5.1.1 UFSAR Based Flooding5.1.1.1 Probable Maximum Precipitation This discussion focuses on theProbable Maximum Precipitation (PMP) and its impact on thelocal drainage basins. For Oconee, there are two (2) drainage basins of concern when impactedby precipitation.

The first basin is the larger Keowee reservoir drainage basin that encompasses an approximate 439 square mile area (Updated Final Safety Analysis Report (UFSAR) 2.4.1.2).

This basin is associated with "External" rainfall and its analysis.

The second basin is the smallerlocal drainage basin which is associated with "Local" (or ONS site related) rainfall and itsanalysis.

The local drainage basin can be further divided into two areas. The first encompaSSes an approximate 129 acre area around Oconee Nuclear Station and the second is the approximate 9.5 acre local drainage basin around Keowee Hydro Station.

The Oconee local drainage basin isPage 4 Flood Walkdown Report -NRC 50.54 (f) NTTF Recommendation 2.3,.iLLI I 'U,... rluul UiUUI! RU q~lJI A..,37U[UJ)[

characterized by a ridge line on the north and west that slopes east-south-east into the relatively level yard (Approximate Elevation:

796 feet). On the east side-of the. yaird, the terrain continues its slope to the east-south-east to the Keowee river channel (Approximate Elevation:

672.5 feet).UFSAR Section 2.4.2.2 defines ther Probable Maximum Precipitation (PMP) as 26.6 inches ofrain falling within a 48-hour period, thus proviiding the magnitude (quantity) of rain and theduration of the rainfall event. The distribution of they rainfall

• over the 48 hour5.555556e-4 days <br />0.0133 hours <br />7.936508e-5 weeks <br />1.8264e-5 months <br /> period was,patterned after an actual storm that occurred on August 13-15, 1940 (UFSAR 2.4.2.2).

The UFSAR states that "essential"'

systems and componentsr are designed, fabricated and erectedto Withstand forces that might be imposed by natural phenomena that include, in part, groundwater and flood (UJFSAR 3.1.2). The essential systems and components were defined to includethe Reactor Coolant System, Reactor Vessel InternalS, Reactor Building, Engineered SafegUards Systems and the Electric Emergency Power Sources.

As delineated ini UFSARSection 3.4.1 1,*Class 1 structures have measures to protect them from floods. Section 3.4.1.,1 states that theplant yard elevation is 796.0 feet mean sea level (msl) and the minimum external accesselevation for the Auxiliary, Turbine and Service Buildings is 796.5 feet msl, creating a 6 inchwater "sill". This sill constitutes a barrier to flood water entering Class. 1 Structures and provideswater detention capacity (ponding) over the yard area, thereby reducing the impact of*a storm'speak rainfall.

Also, there is "a surface water drainage system that protects the plants facilities from local precipitation"'

(UrFSAR-3.4.1!.1).

Implicit to the surface water drainage system :(thecorrugated metal pipe drainage system),

is the free edge along: the cast-south-east Side of theplant. While surface water doesn't cascade down this slope during normal rainfall (erosion),

thisflow path provides an additional feature in the overall flood mitigation strategy.

In summary,rainfall would initially surface-flow to the yard drainage system and be removed from the plant*yard, until the: yard drainage system reaches its capacity.

Water would then begin (starting at thecatch basin locations) to pond over the plant yard where it would be detained until the yard drainsystem "catches up" with the precipitation, or in the most extreme cases,: the water would surfaceflow to and cascade over the free edge and down the eastern slope of the plant.Adverse weather conditions that could be assumed to simultaneously occur with the PMP couldinclude typical storm conditions, making work outside dangerous or difficult.

However, Lthelicensing basis protective features for the PMP event are passive in nature and exist or :are stagedprior to the event occurring.

The weather conditions that initiate the PMP flooding event are described in the Oconee Severe.Weather Preparations PrOcedure.

Specifically, these conditions include rainfall in excess of4 inches of rain :in any 6 hour6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> period. This procedure dictates actions to be taken prior to theweather event arriving.

Because this flooding event is 48 hrs in duration, local flood heights vary with time.A new calculation for the Licensinag Basis PMP which estimates the local flood heights around'the ONS site is in the review stage. However, at the time of this report, the calculation was notPage 5.

Flood Walkdown Report -NRC 50.54 (f) NTTF Recommendation 2.3* '.':: L:I ". "...Y. 7.,-". ." J .L ....... .J.. 10 t.Z:'"'2J

'complete and is not incorporated into the CLB. (Note

Mitigating actions fo~r the preliminary calculation is discussed in Section 5.2 of this report,)

.. ..5.1.1.2 Keowee Reservoir Retention Asecond external flood initiator is the Keowee Reservoir.

Section 2.4.1 .1, "Site and Facilities" of the UFSAR describes this feature by the height of the retention dikes and dams of the KeoweeReservoir.

It states: "All of the man-made dikes and dams forming the Keowee ReservOir rise toan elevation of 815 ft msl including the intake channel dike." Lake Keowee was formed in 1971by the Keowee Dam on the Keowee River and the Little River Dam on the Little Ri'ver. Itsprimary purpose is to provide cooling water for ONS and a water source for the Keowee HydroElectric Station.

At full pond, 800 ft msl, Lake KeoWee has a surface area of 18,373 acres, aShoreline of approximately 300 mi, and a v~olume of 955,586 ac-ft, and a total drainage area of'about 439 square mi. The J ocassee and Keowee Reservoirs and the hydroelectric stationslocated at the reservoirs are owned and operated by Duke Energy. The UFSAR further describes floods on the Keowee Reservoir by stating "While spiliway capacities at Keowee and Jocasseehave been designied to pass the design flood with no Surcharge on full pond, the dams and otherhydraulic structures have been designed with adequate freeboard:

and structural safety factors tosafely accommodate the effects of the maximum hypothetical precipitation.

Because of the time-lag, characteristics of the runoff hydrograph aftera storm, it is not, considered credible that themaximum reservoir elevation due to the maximum hypothetical precipitation would occursimultaneously with winds causing maximum wave heights and run-ups."

(UFSAR Section2.4.2.2.)

There is one exception to the Keowee Reservoir Retention dikes and dams maximum815 ft mnsl elevation.

This exception is described as "Two Reinforced Concrete Trenches extendthrough the Intake Dike with a minimum elevation of 810 ft' msl, with all removable coversremoved.

These trenches are protected from wave action by the Condenser Cooling Water(CCW) Intake Structure and the Causeway at the west end of the Intake Structure.

Therefore only the maximum reservoir elevation of 808 ft msl is applicable with regard to flooding t~hroughthe reinforced concrete trenches."(UFSAR Section 2.4.2.2)UFSAR Section 18.3.8, Federal Energy Regulatory Commission (FERC) Five Year Inspections describes the Keo wee Reservoir Retention items as: the Keowee River Dam, Little River Dam,Little River Dikes A, B, C, D, Oconee Intake Canal Dike, Keowee Spiliway, Keowee Intake, andKeowee powerhouse.

This sections states, "Inspections of the Keowee River Dam; Little RiverDam; Little River Dikes A, B, C, D; Oconee intake Canal Dike; Keowee Spillway and LeftAbutment, Keowee Intake and Powerhouse are performed in accord ance with the requirements in 18 CFR Part 12, Safety of Water. Power Projects and Project Works."5.1.1.3 SSF Flood Protection:

An additional Licensing caveat exists in ONS's UFSAR. UFSAR Section 9.6.3.1i describes thedesign basis loads for the Standby Shutdown Facility (SSF). 'The original basis for theSSF stated, "Flood studies show that Lake Keowee and Jocassee are designed with adequatemargins to contain and control floods...

The Final Safety Analysis Report (FSAR) addresses OCronee's location as ona ridgeline 100' above mnaximum known floods. Therefore, externalPage 6 Flood Walkdown Report -NRC 50.54 (f) NTTF Recommendation 2.3flooding due to rainfall affecting rivers and reservoirs is not a problem.

The 5SF is within thesite boundary and, therefore, is not subject to flooding from lake waters."

(UFSAR Section9.6.3.1).

In: 1983, a Jocassee dam failure study Was completed to determine-the maximum water-h~eight around the SSF if a postulated failure of the Jocassee'Dam is considered.

The results ofthe Study estimated a peak flood elevation of 817.45 ft msl at the Keowee darn, and an ONS yardflood level of 4.71 ft. In response to this study, ONS erected several walls approximately 5 ft tallaround the entrances tO the SSF as a risk reduction measure.

This was not part of the designbasis. Based on Oconee's September'26, 2008 response to a 10CFR 50.54 (f) request forinformation, ONS increased the height of the flood wall, around the SSF by 2.5 ft. The :resulting elevation of 803.5 ftresl provides additional margin.The UFSARSection 9.6.3.1 was. updated to say: "As a P RA enhancement the 5SF is providedwith a five foot eXternal-flood wall which is equipped with a water tight, door near the southentrance of the SSF. A stairway over the wall provides access to the north entrance.

The yardelevation at both the north and the south entrances to the SSF is 796.0 ft msl .Based on the as-built configuration of the 5' flood wall provided at the north entrance and the flood wall at thesouth entrance to the SSF,. SSF external flood pr'otection is provided for flooding that does notexceed 80.1 feet above mean sea level." In its current as-built condition, the SSF has flood.protection features up tO elevation 803 '-6" msl.5.1.2 Safety Evaluation Based Flooding (Pending, NON UFSAR)5.1.2.1 Jocassee Sunny Day Failure -Safety Evaluation (SE)A unique external flood initiating eyent is the Sunny Day Failure of the Jocasseel Dam. Thisinitiator is derived from an NRC SE dated January 28, 2011i, addressing commitments made inregards to the June 22, 2010 Confirmatory Action Letter (CAL) to address external floodingconcerns.

This initiating event is 'unique in that its basis originates from an SE, not the UFSAR=.The discussion below is a synopsis of the SE.inr April 2006, the U.S. NRC staff questioned the flood protection barrier for the SSF. The NRCidentified that the licensee had incorrectly calculated the Jocassee Dam Failure frequency

.andhad not adequately addressed the potential consequences of flood heights predicted at ONS.Based on concerns raised by the NRC, by letter dated August 15, 2008, (ML08 1640244) theNRC requested information in a 10CER 50.54(f) letter. Duke Energy responded on:September 26, 2008 (ML082750!106)r to the licensee request.

The NRC staff reviewed theinformation and based on the review, the NRC staff found' that the information proyided by thelicensee did not demonstrate that the :ONS site would be adequately protected from. externalflooding events. SpecifiCally the licensee did not:(l) provide an adequate inundation study, (2)provide a deterministic resolution of this matter, and (3) provide a schedule to resolve theexternal flooding issue in a timely manner.After further correspondence, the NRC Staff issued a Confirmatory Action Letter to the licenseeon June 22, 2010, requesting the following-:

1) submit to the NRC all documentation necessary topage 7 Flood Waikdown Report -NRC 50.54 (f) NTTF Recommendation 2.3demonstrate that the inundation of the ONS site, from the postulated failure of Jocassee Dam,has been bounded 2) by November 30, 2010, submit a list of all modifications necessary to:mitigate the inundation, and 3) make all necessary modifications by November 30, 2011.The staff also requested that the compensatory measures (CMs) listed in the CAL remain inplace until final resolution has been agreed upon between the licensee and the NRC staff.The SE goes on to discuss its evaluation of the methods and parameters chosen to be used byDuke Energy. It concludes by stating:

"The u nmitigated Case 2 dam breach parameters thatWere used in the flooding models, provided by Duke Energy for ONS site, demonstrated that licensee has included conservatisms of the parameters utilized in the dam breach scenario.

Theseconservatisms pr'ovide the staff with additional assurance

.that the above Case scenario willbound the inundation at ONS, therefore providing reasonable assurance for the overall floodingscenario:

at the site. This new flooding scenario is based on a-random

-sunny-day failure of theJocassee Dam. This Case 2 scenario will be the new flooding basis for the site." (SE datedJanuary 28, 2011) The final commitment listed in the SE states that the, licensee has committed to keep the compensatory measures in place until final resolution has been agreed upon betweenthe licensee and ;the NRC staff."There are no assumed adverse weather conditions that occur simultaneously with the Dam breakand its associated mitigation strategies.

The Case.2 scenario, as described in the SE produces aflood height of 81 5'-0" msl in the Oconee Yard. This flooding event lasts approximately 8 hour9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br />sbefore the: flood waters recede below yard level. The CAL dated. June 22, 20110 has a list. ofcommitted compensatory measuires tO be implemented by the licensee.

The Compensatory Measures are listed in the-table below:,Table 1: Compensatory Measures from CAL dated June 22, 2010No. CompenSatory Measures Implementation

......_ StatusPerform flooding studies using the 1-EC- RAS model for, comparison with1 previous DAMBRK models to more accurately represent anticipated flood Completed

___heights in thie west yard following a postulated failure of the Jocassee DamMaintain plans, procedures (Jocassee and Oconee) and guidance documents implemented (Oconee) to address .mitigation of postulated flood eventswhich could render the SSF inoperable and are consistent~with cunrent2 perspectives gained foilpwing the H-EC-RAS sensitivity studies and the Completed-

'subsequent 2d inundation studies.

TO the extent p~ractical, the mitigatiOn strategy is similar to existing extensive plant damage-scenario (B.5.b)___equipment, methods and criteria.

Duke Energy H-ydro Generation will create a guidance document to3 .consolidate river management and storm managemnent processes.

Completed

___the Jocassee Development and the Keowee Development)

________Page Flood Walkdown Report -NRC 50.54 (1) NTTF Recommendation 2.3I iII 1 A ¥ r,

• Itll... .o ,No. Compensatory Measures Implementation

_____Status Maintain a dam safety inspection program that includes:

(I) weekly damnsafety inspections of the Jocassee Dam by Duke Energy personnel, (2) dam4 safety inspections following any 2-inch or greater rainfall or felt seismicCoped event, (3) annual dam safety inspections by FERC representatives, (5) fiveCoped year safety inspections by FERC approved consultants, and (6) five yearunderwater inspections......

Maintain a monitoring program that includes:'

(1) continuous remoteS monitoring from the Hydro Central Operating Center in Charlotte, NC, (2)5 monthly monitoring of observation wells, (3) weekly monitoring of seepage Completed

___monitoring points, and (4) annual surveys of displacement monuments.

6 oASsign oasean Oconeestts engineer as Jocassee Dam contact to heighten awareness Completed Install ammeters and voltmeters on Keowee spillway gates for equipmentCoped 7__ condition monitoring.Coped 8 Ensure Forebay and Tailrace level 'alarms are provided for Jocassee toomlee___ support timely detection of a developing dam failure.Coped Add a storage building adjacent to the Jocassee spillway to house the backup Coped___ spillway gate operating equipment (e.g. compressor and air wrench)Coped Obtain and stage a portable generator and electric drive motor near the10 Jocassee spillway gates to serve as a second set of backup spillway operating Completed

___equipment.

Conduct Jocassee Dam failure Table Top Exercise with Oconee participation Coped11__ to exercise and improve response procedures.Coped 12 Instrument and alarm seepage monitoring locations for timely detection ofCoped12_ 'degrading conditions.Coped 13Provide additional video monitoring of Jocassee Dam (e.g. dam toe13__ abutments, and groin areas) for timely assessment of degrading conditions.

Completed 14 Obtain and stage a second set of equipment (including a B.5.b-type pump) Completed 14__ for implementation of the external flood mitigation guidance.

________15 Conduct Jocassee Dam/Oconee Emergency Response Organization Drill to Completed

___exercise and improve response

.procedures._________

5.2 Flood Mitigating Features and Their Effectiveness The Current Licensing Basis (CLB), as defined by 10CFR 54.3, is the set of Nuclear Regulatory Commission (NRC) requirements applicable to a specific plant, plus a licensee's docketed andcurrently effective written commitments for erisuring compliance with, and operation within,applicable NRC requirements and the plant-specific design basis, including all modifications andadditions to such commitments over the life of the facility operating license.

It also includes theplant-specific design basis information, defined by 10CFR 50.2, as documented in the mostrecent UFSAR as required by 10OCFR 50.71.The set of NRC requirements applicable to a specified plant CLB includes:

• NRC regulations in 10 CFR Parts 2, 19, 20, 21, 26, 30, 40, 50, 51, 54, 55, 70, 72, 73 and100 and appendices theretoPage 9 Flood Walkdown Report -NRC 50.54 (f) NTTF RecOmmendation 2.3* Commission Orders* License Conditions

• Exemptions-

• Technical Specifications

• Plant-Specific design basis information defined in 10 CFR 50.2 and documented in themost recent UFSAR (as required by 10 CFR 50.71)* Licensee Commitments remaining in effect that were made in docketed licensing correspondence (such as licensee responses to NRC bulletins, License Event Reports,Generic Letters and Enforcement Actions)*Licensee Commitments documented in NRC safety eValuations Based on this description of the CLB and the above listed ONS specific CLB flooding initiators, a list of features has been compiled.

Below is a description of thie different features andjustification as to why they have been included based on CLB. Many of the features are actuallygroups of smaller features and for convenience has often :been paired together.

-5.2.1 PMP Protection FeaturesThe first group is features

1. 1- #9.These features are included because of the PMP initiating flood as described above. They are alleither at yard elevation

(--796 ft msl) or below grade and are listed below:Flood Waikdown Feature#1 -Auxiliary Building Exterior Subsurface Walls and Seals#2 Radwaste trench covers and seals from Radwaste Facility to Turbine BuildingRadwaste trench covers and seals from Radwaste Facility to Auxiliary Building#4--Interim Radwaste trench covers and seals#5- Manhole 7 Cover, Techni'cal Support Building vault and seals#6- Borated Water Storage Tank (BWST) trench Covers#7- Yard Drain system#8- CT-5 trench covers :in Auxiliary Building#9-, PMP rainfall event flood barriers sandbags and Gryffoiyn Early in 2012, an issue arose about the PMP analysis for the ONS yard. This led to a thoroughinvestigation of current status of various structures on site and their ability to resist flood watersfrom a PMP event. A vendor is currently working on a new analysis of the ONS yard to gainmore precise local flood heights around the yard. A walkdown was performed for all Class 1structures and other structures deemed critical to safe shutdown using preliminary results fromPage 10 Flood Walkdown Report -NRC 50.54 (f) NTTF Recommendation 2.3wirnnoIu iru.u puuua ....... .. 1 Cf 3.21_.I)')

an initial draft' version of the revised PMP analysis.

'That analysis is currently in final review andindicates thait the Versioni Used for the walkdowns was conservative..

The walkdown sueyed thebuilding envelope to identify weaknesses in flood protection.

It was determined that ONS is innonconform~ance with the Licensing Basis as described in UFSAR Section 3.4.1.1 becauise watermay exceed a 6 inch sill in a few areas surrounding the Class 1 structures.

All other areassurrounding the structures were' determined to be acceptable.

Compensatory measures weretaken in the form of Flood Barrier Sandbags and Gryffolyn coverings.

These barrier locations and heights are based on a preliminary analysis that was performed on local flood heights in theyard. This information is being v¢alidated by the vendor analysis.

The~se compensatory measurestemporarily protect some of the site, other places on site were either found to be acceptable orhave been entered into PIP and resolutions have been made. ONS received a NRC finding on theUFSAR no~nconformarnce issue. The NRC finding is described in the Oconee NRC Inspection Findings Report 2012003.

All issues are either currently being tracked or resolved in PIP orhave been found toube acceptable.

None of these features require a repeat walkdown based onNEI 12-07,. Section 5.5 guidelines.

The comprehensive walkdowns performed early in 2012 asdocumented in PIP meet the intent and requirements of NEI 12-07.The overall effectiveness of these features can be described as adequate to protect againsthistoric rainfall events. A PIP that describes an issue with the RadwaSte facility trench thatenters the Auxiliary' Building~was written in 2012. An open penetration was discovered in thistrench. During normal rainfall events when it is possible to incur water build up against the 6"lip, water does not leak into the Auxiliary Building through below grade penetrations.

Floodlevels such'as those produced during the CLB PMP event have never been approached during arainfall event at ONS. In the recent years, two significant rainfall events have occurred thatwould have challenged the integrity of the water tightness feature of the trench. One is tropicalstorm Jeanne, on September 28, 2004, that dropped 3.17 inches of rain in 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> on Seneca,South Carolina (SC). The other tropical storm being Cindy, on July 7, 2005, dropped 2.93inches of rain in 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> on the Same location.

If the water tightness of the subject trenches hadbeen degraded and they were challenged on these dates, evidence would have likely beenindicated by the level indications in the Low Activity Waste Tank (LAWT). PIP database:

research found no record of excessive filling of the LAWT on these days. In addition, Operations personnel indicate no noticeable correlation between LAWT levels and rainfallevents, indicating that the subject trenches (and the Auxiliary Building as a whole) have not beensubject to any unanticipated inflows.

At the time the PIP was written, the trenches that enter the.Auxiliary Building served as thle flood barrier and'the Au~xiliary wall Was considered tobe~functional but non-conforming.

However, the functional expectations of ONS's SelectedLicensee Commitment (SLC) are satisfied.

To resolve the nonconformance, a modification installed an isolation valve and flow limiting device to ensure water fr~om these trenches couldnot enter the Auxiliary Building unimpeded.

Two shortcomings were identified during the walkdown process of these items. The first'shortcoming related to following the design control process and the second related to the PMprogram for the subsurface protective features.

Because of this issue, PIP's have been Written toenhance the PM programs on the yard drain system, as well as the below grade pernetrations.

Page. 11 Flood Walkdown Report -NRC 50.54 (f) NTTF Recommendation 2.3C..T.I..

jrri" flD IpV, CU' MCN/ITIUVI INFnR i'ium mmou;pol

..it~u.. ...J...13cr OI)1Engineering Changes.

have been initiated to control-labels for the ,below grade auxiliary penetrations identifi'ed" as- flood features, on site design drawings.

Features

1. 1 through #9 are passive features that are very rarely affected by normal plantoperations.

All of these items, with the exception of the yard drain system, are listed 'as passivedesign features in an Oconee Site Directive.-

The inclusion of features on the ,passive designfeature list ensures that the items remain functional and in place. There is a controlled processfor removing these features from service.

If at any time there is a threat of external flood due toPMP, the Operations Shift Manager (OSM) is notified and the feature is immediately returned toservice.

A piP has been 'written to address the Yard Drain System with respect to passive design.5.2.2 Keowee Reservoir Retention FeaturesA second group consists of Features

1. 10 -#16. These features are included because they are partof the Keowee Reservoir Retention items as described above. Listed below are the seven Flood Walkdown Feature :#10- Keowee river dam#11- Oconee Intake Canal Dike#12- Little River Pam#13- Little RiVer Dikes A, B, C, D#14- Keowee Intake#15- Keowee Powerhouse

1. 16- Keowee SpiliwayThis is the same list of dikes and dams listed in section 18.3.8 of the UFSALR. Each of iheseKeowee Reservoir retention items is well maintained and inspected on a regular basis. Section1 8.3.8 of the UFSAR dictates that these items are to undergo 5 year FERC Themost recent FERC inspection was performed in, 2012. There are also yearly FERC and DukeEnergy internal inspections of these same features.

Additionally, Keowee personnel inspect theearthen structures every two weeks. This inspection data is collected and stored in a hard copylog book at Keowee Hydro Station.

Any degradation or nonconforming items found in theseinspections would be documented and included in PIP. The scope of the yearinspections is sufficient in meeting the intent of the NEI 12-07 walkdowns.

The personnel performing these inspections have enveloping qualifications as described in NEJ '12-07. ONShas elected to not perform rework for the features that have been inspected based on FERCinspections.

The items listed above can be described as Very effective in performing their designfunctions.

No PIP's or corrective actions were identified for these items on the basis of theirability to retain the Keowee Reservoir.

'Page 12 Flood Walkdown Report -NRC 50.54 (f) NTTF Recommendation 2.3CO,,N.tA

........

.a lt't V c rTD rtPv I Vr'vl M A TIANr/5.2.3 SSF Flood Protection FeaturesThe third group consist of features

1. 32- #34. These features are included because they are theexterior flood protection features for the SSF. Listed below are the three features:

Flood Walkdown Feature#32- 5SF flood barriers including exterior walls#33- SSF steel plate with CO2 refill access#34- SSF External wall penetrations These features form the exterior flood protection wall that was installed as a risk reduction measure for PRA. Even though these items are not the design basis for the SSF, they have beenincluded on this list because they are described in the UFSAR. All SSF external wallpenetrations below elevation 803.5 ft msl were walked down in 2012 by a member of the CivilDesign Basis team. This walkdown effort is recorded in PIP and any recommendations ordegradation of items are also captured and being tracked in PIP. The SSF flood barriers, including all three features listed above, are also included in the Passive Design Features list..These features ensure the SSF has flood protection up to an elevation of 803.5 ft msl. The threefeatures listed above can be described as being effective at performing their intended function.

The exterior flood walls as well as the steel plate with Carbon Dioxide (CO2) refill access havenever been challenged by flood waters. These are passive features and based on the acceptance criteria they are judged to be acceptable and are expected to survive a flood event.5.2.4 CAL Interim Compensatory Measure (ICM) FeaturesThe fourth group consists of Features

1. 17 -#31. Their purpose is to mitigate flood conditions based on a postulated sunny day failure of the Jocassee Dam, as described in Section 5.1.2.1 ofthis report. This list was derived from the fifteen CAL Compensatory

Measures, as described above, and the actions taken by ONS in order to satisfy the CAL. These features include plantflood protection procedures, early flood detection warning equipment housed at Jocassee Hydro,and emergency equipment housed at Oconee and operated under emergency procedures.

The listof features is provided below:Flood Walkdown Feature#17- EM 5.3 Procedure

1. 18- AP/0/A/1700/047 Procedure

1. 19- Jocassee Flood-mitigating plans and procedures

1. 20- Duke Energy Hydro generation guidance document#21- Dam safety inspection program#22- Maintained monitoring Program#23- Keowee Spillway enhancements

1. 24- Jocassee Forebay and tailrace alarmsPage 13 Flood Waikdown Report -NRC 50.54 (f) NTTF Recommendation 2.3CONT,.INJ JECUIUT'.'

VVn~ouIrIIOI, Ju puuilc dJislosU~

Iure Rune,..'i h~ .3YUd)Iij Flood Walkdown Feature#25- Jocassee storage building with backup spiliway operating equipment

1. 26- Portable generator and electric drive motor near the spiliway#27- Documentation of Table top Exercises

1. 28- Instrumentation and alarm selected seepage monitoring locations

1. 29- Video monitoring of Jocassee Dam#30- Second set of B.5.b like equipment

1. 31- Jocassee dam-ONS response drill documentation Some of the above listed items are simply historical documentation describing events that tookplace, or proving compliance with the Compensatory Measures.

Others are early warningdetection

devices, such as the video monitoring equipment at the Jocassee dam. The items thatwere walked down at Jocassee were determined to be very effective in performing their intendeddesign function.

No issues were found with any of the equipment maintained at Jocassee.

A self assessment was recently performed at ONS for the items listed above. ONS has a NRCcommitment to perform this assessment to ensure the Interim Compensatory Measures described in the CAL are maintained.

The assessment report identified one deficiency and fourrecommendations.

The deficiency and recommendations are pertinent to the Flood features#17-31 and are discussed below.Deficiency I. Generated a PIP in the Corrective Action Program on repair of Keowee spillway gatevoltmeters.

The inoperability of these instruments is a deficiency as noted in theNEI 12-07 walkdown of plant flood protection features.

Recommendations (enhancements)

1. Determine if Jocassee Emergency Communication Equipment should include a mobilesatellite phone to address widespread loss of power concerns and secure equipment ifwarranted.

2. Inform Jocassee Dam Contact of any new Jocassee monitoring equipment issues that mayarise in the future. The Jocassee Dam Contact should generate a tracking PIP to informONS Station management of status and resolution.

-3. Evaluate using non ethanol fuel or add a fuel stabilizer to the electric generator that, powers backup spillway equipment.

4. Evaluate draining and replacing the fuel in the electric generator at some frequency (Halepump has fuel changed every, 2 years)These recommendations are captured as Corrective Actions in the PIP for the self assessment.

Page 14 Flood Walkdown Report -NRC 50.54 (f) NTTF Recommendation 2.3Two of the above items, Features

1. 17 and #18, are procedures, Engineering procedure (E.M. 5.3)and Abnormal Procedure AP/0/A/1700/047 (AP-47).

These are the only procedures identified asa Flood Feature that could reasonably be simulated.

Both procedures have previously beenexercised during Emergency Drills and OPS personnel are trained on them. A new revision wasreleased in August 2012 and was simulated.

Some aspects of the procedures, such as turning onequipment, making nozzle connections, and others, are not actually performed during thesimulation but do not devalue the simulation since ONS has documentation that these activities have been performed and timed. All issues identified during the simulation, were captured in thePIP process.

None of these issues were deemed to cause the procedures to be non-effective.

Allsystems were found to be functional and all operator actions were found to be feasible.

Withminimum staffing available and the complex evolutions that take place in AP-47, the simulation confirmed that adequate staff resources were able to complete the tasks during the event.Feature #20 corresponds with the CAL Interim Compensatory Measure #3 (1CM #3). DukeEnergy Hydro Generation developed the "Keowee -Toxaway Project High, Water Operations Process" for managing the river management and storm management process.

This processdefines the operating plan for lake level management of the Keowee-Toxaway (K-T) project,which includes the Lake Toxaway, Lake Jocassee, Lake Keowee, as wvell as the Bad Creekreservoir, in consolidating river management and storm management in anticipation ofsignificantly high precipitation and storm runoff events. Aspects of thifs high-water operations process are summarized below:* Operations Issue -definition of the plan* Risk Management Summary -A description of the risk to the public safety, mitigation

strategy, and responsibility for ensuring execution of the plan.*Operating Commitments

-Defined commitments of each organization in the K-TProject, Hydro Generation Management and Staff, and Hydro Central Operating Center,for execution of the process for mitigating of significantly high precipitation and stormrunoff events* Compensatory Measures

-A description of Hydro Central Operating Center staffing24/7 to execute the process as well as contingency operating locations should it beneeded.* Contingency Operating Actions -A description of actions to be performed by HydroCentral including daily monitoring of weather forecasts and weather radar for potential abnormal rainfall amounts that could cause a rapid rise in the K-T Hydro projects, including monitoring of the K-T area lakes for rapid lake level rise (rapid rise definedfor Jocassee as a 0.6 foot rise per hour).This feature was found to be acceptable.

Feature #21 corresponds with the CAL 1CM #4. All aspects of maintaining a dam safetyinspection

program, as defined in this 1CM, were found to be met. No issues were identified during walk-downs of these systems/components or documents.

The Jocassee dam safetyPage 15 Flood Walkdown Report -NRC 50.54 (f) NTTF Recommendation 2.3inspection program is a very comprehensive program utilizing multiple resources and methodsfor inspection of the water retaining components of the Jocassee Project.Feature #22 corresponds with the CAL ICM #5. All aspects of the Jocassee Dam monitoring program were found to be met. No issues were identified.

The program is comprehensive andencompasses redundant means for identification of any issues associated with the Jocassee Damand its supporting structures.

Additionally, instrumentation is in place, operable, and is properlymaintained to support the monitoring program.Feature #23 is associated with the Keowee Spillway Enhancements.

'[he Keowee Spillwayenhancements are comprised of digital voltmeters and ammeters that were installed at all fourspillway gates. These digital readouts allow operators controlling the spillway gates to quicklyand easily see the voltage and amaperage during gate movement prevent damaging the gates, ifthe gates stick or bind during movement.

Upon inspection, all four sets of ammeters wereworking properly but all four sets of the voltmeters were out of service.

The voltmeters werepreviously discovered to be inoperable and entered in PIP. The PIP was closed to a work order,because the failure of the voltmeters did not prevent the gates from operating, and was notreportable to FERC. A new PIP was written to document the issues of the voltmeters andincluded their association to the procedural issues for operating the gates. The gate operating procedure does not provide instruction to the operators on the use of the voltmeters, or any backup methods for reading voltage during operation.

The Keowee" spillway voltmeters are beingdescribed as a deficiency, as defined in NEI 12-07. This was the only identified deficiency fromthe walkdown this feature.Feature #24 corresponds with the CAL 1CM #8. Jocassee Forebay and Tailrace instrumentation (alarms) were the subject of a walk-down at the Jocassee facility.

The instrument systems wereobserved to be operable with no issues identified.

Procedures are in-place at Jocassee and theHydro Operations Center (HOC) to address these alarms should they be activated.

No findingsidentified.

Feature #25 corresponds with the CAL ICM #9. A storage building which houses backupoperating equipment for the spillway gate is located next to the Jocassee spillway and containstwo independent sets of backup operating equipment for controlling the spillway gate.* One means consists of a diesel powered air compressor and an air operated wrench(which is discussed in this 1CM 9).* A separate means consists of a portable powered electrical generator and an electricwrench (which is discussed in 1CM 10)This equipment is dedicated for use in providing a backup means of operating the Jocasseespiliway gates and has no other purpose.

The storage building and backup equipment was ingood physical condition.

The air compressor and air wrench are tested monthly for properoperation.

(This Work Order also checks the electric generator and electric wrench mentioned in1CM 10). The startup instructions contain a check for sufficient fuel in the compressor.

Page 16 Flood Walkdown Report -NRC 50.54 (f) NTTF Recommendation 2.3CUN'I AIN5 SEUuRrI Y SIINMITIVE INFORKMAT ION.witnnolil from puonic alscws~ura¢ Uu~Ad Feature #26 corresponds with the CAL ICM #10. The storage building which houses the airoperated backup spiliway operating equipment also contains a separate set of electrical backupoperating equipment.

The electrical set is comprised of a diesel generator and an electricpowered wrench. The equipment was in good physical condition and a demonstration ofpowering the backup electric wrench from a generator was observed.

The generator and airwrench are tested monthly for proper operation.

Part of the startup instructions checks forsufficient fuel in the generator.

An interview with Jocassee management confirmed that theequipment in the storage building is dedicated for providing backup operational control for theJocassee spillway gates, and is not used for any other purpose.Feature #27 corresponds with the CAL 1CM #1l 1, to implement table top exercises.

A table topexercise to evaluate the use of AP/O/Ai1 700/047 and EM 5.3 was conducted on 6/28/2010 anddocumented in PIP. Enhancements have been incorporated into API0/A/1 700/047, the OconeeEmergency Plan and Hydro EmergencY Actions plans. Proposed actions related to EM 5.3 havebeen augmented with actions from the 12/15/2010 Oconee Emergency Drill 2010-02.

TheJocassee Emergency Plan was revised to make the Oconee OSM the first contact for a damfailure event.Feature #28 corresponds with the CAL 1CM #12, for seepage monitoring instruments.

Instruments at selected seepage monitoring points were verified by visual inspection with theJocassee staff and Hydro Central staff. The instruments have a wireless feed to a repeater stationlocated on the crest of the Jocassee dam which transmits instrument data to the Bad CreekControl Room and Hydro Central.

The alarm logic is based on rate of level change and initiates procedure action for immediate operator response to verify conditions and initiate appropriate action level.Feature #29 corresponds with the CAL 3 for visual mopitng of Jocassee Dam. ]cameras are located at the Jocassee intake;W~

7 for security and (7) for monitoring.lake level.

cameras are located at the Jocassee discharge or security 7 formonitoring the Dam structure and discharge.

No findings were 1 ntified.

Ant exploration of theJocassee site which included observations of the intake and discharge was conducted.

Wevisually observed that camera (used for monitoring) had been installed in addition tothe normal securit (b)(7)(F)

J. The Jocassee supervisor gave a tour of theJocassee control room and demonstrated how the additional cameras could detect potential Damfailures.

Cameras gave real time images of actual water level conditions and could monitor theDam structure.

Feature #30 corresponds with the CAL 1CM #14 for the B.5.b like equipment.

This feature waswalked down at the same time as much of the AP-47 procedure simulation walkdowns.

The"second set" of equipment, as referenced in the June 22, 2010 CAL, is comprised of a secondHale pump permanently located at Chemical Treatment Pond (CTP)-l and a External FloodMitigation (EFM) trailer located at the base of the Oconee Office Building.

The primary set ofsimilar equipment is the actual B.5.b equipment located inside its shelter building at the OconeePage 17 Flood Walkdown Report -NRC 50.54 (1) NTTF Recommendation 2.3...... TV&--3I,;;

FR.... C-.Intake Canal. The overall effectiveness of this feature is determined to be functional.

Minorissues were noted with this equipment.

The first issue was that a copy of an enclosure to AP-47 which directs how EFM trailer is to beused, and is stored inside the trailer, was found to be wet and damaged but still useable.

Thisissue was immediately resolved.

Next, there were concerns about the mounting locations for the fire hoses throughout the yard.Because these hoses will be deployed across the yard during the flood, there were questions ifthe hoses would be adequately secured.

There were also concerns about the appearance of asmall oil leak at the Hale pump. This issue was resolved.

The suction source for the Hale pump,CTP-l1, had visible accumulations of algae floating in the pond. This raised a question regarding whether the strainer would become clogged.

Weaknesses in the PM program for the suctionpipes at the Hale pump were also discovered.

Input from Site Chemistry regarding the algaesupports the determination that the strainer would not clog and the Hale pump is designed tooperate with algae in the water. This issue was entered into PIP and is being tracked.

None ofthese issues keep the pump from performing its intended function.

Because this equipment is either permanently located above the flood plain or is procedurally moved to a higher elevation, the flooding event will not impact operator actions.

It has beenvalidated that ONS, at minimum required

staffing, has enough operators to complete intendedactions in the operating procedures.

Feature #31 corresponds with the CAL ICM # 15. The results of Oconee Drill 2010-02 aredocumented in PIP. Proposed changes to EM 5.3 are captured in PIP actions to revise EM 5.3and remain open. The next External Flood Mitigation related drills are scheduled for the firstquarter of 2013.5.2.5 Other FeaturesFeature #35 is the last feature on the Flood Walkdown list and corresponds to the Site Elevation and Topography.

NEL 12-07,'Appendix A, provides guidance on this topic as follows:* Compare the current site topography with the topography assumed in the currentlicensing basis flood evaluation

• Assess differences to determine if they could affect water flow or flood levels and createvulnerabilities in existing flood protection features* The need for a land survey for elevations will depend upon the accuracy of theapplicable drawings and site topographical documents ONS had already begun an effort to accomplish the tasks listed above prior to the release of NEI12-07. This feature is included in order to remain in compliance with NEI 12-07 and to track theprogress of the Site Elevation and Topography effort. To date, the topography has been found toPage 18 Flood Walkdown Report -NRC 50.54 (f) NTTF Recommendation 2.3CONTIAINS SiCURIlI V ! ILv I IUI'.be consistent with drawings and elevations assumed in plant documentation associated with theflood features, with the exception of the 6" sills protecting some Class 1 structures.

The #35 Flood Feature Walkdown items only represent features that the ONS Current Licensing Basis credits for flood mitigation.

There are other features on site, such as the temporary Intake Dike Flood Barrier and thepermanent swale wall located above CTP-1, that ONS does not take credit for in the CLB. Theseitems have not been included.

These two items decrease flooding levels from a postulated SunnyDay Failure of Jocassee.

The swale wall, which is located north of CTP-1, keeps CTP-l frombeing damaged during the event. The intake dike wall significantly lowers the water level in theyard from the first peak of flood waters.The 10CFR 50.54(f) request for information regarding External Flooding does not include anyinternal source of flooding.

Therefore many internal flood features onsite have not beenincluded because their design and licensing basis is based on an internal source of flood waters.5.2.6 Flood Warning SystemsOconee has no warning systems credited for external flood by the CLB to detect the presence ofwater in rooms important to safety. Oconee, as it is licensed, is considered a dry site and nowater was assumed to enter buildings due to external flooding events. The only warning systemput in place is the equipment listed as features 19-29. These are pieces of equipment that wereeither implemented prior to the CAL or because of the CAL. This equipment is what Jocasseeuses to make a declaration of Condition A or Condition B of the Jocassee Dam.(Condition A andCondition B are the triggering events which initiate the Jocassee Dam Break scenario.

These aredescribed in detail in Emergency Procedures.)

This equipment is critical for the success ofOconee in mitigating the External Flood due to Jocassee Dam Break.5.3 DESCRIPTION OF WALKDOWN PROCESS AND ACCEPTANCE CRITERIAIn order to satisfy the requirements of the requested information in part 1 .h of the Fukushima 10CFR 50.54 (f) letter Sectioni 2.3, staff at Oconee implemented walkdown strategies asprovided by NEI 12-07 and supplemental guidance that was created by the Exelon group.Section 1 .h requests the following information:

1. h Verify that flood protection systems are available, functional, and implementable under avariety of site conditions by reviewing the following:

i. Operator availability, operator

training, timeliness of response, equipment maintenance and operability, back-up availability, operator access under adverse site conditions ii. Methods and acceptance criteria to evaluate exterior barrieriii. Methods and acceptance criteria to evaluate incorporated barriers*

iv. Methods and acceptance criteria to evaluate temporary flood barriersv. Preparations in advance of adverse weather conditions Page. 19 Flood Walkdown Report -NRC 50.54 (f) NTTF Recommendation 2.3Wlminoia 1rom pUwll Ui~ciUSUr¢ IJmuuuv zIj Oconee primarily implemented the methods that were recommended by NEI 12-07 forcompleting the walkdowns.

Most of this information is found in Section 6 of NEI 12-07 whichfully satisfies the requested information from Section 1l.h above.Oconee used the NRC endorsed NEI 1 2-07 document for the walkdown procedure.

Noexceptions to the NEI 12-07 walkdown process were taken by Oconee. Accordingly, Oconeeused the Walkdown forms presented in Appendix 1B of NEI 12-07 to perform the walkdowns.

Asa part of these forms, a peer review system is built in.Oconee applied the provision in NEI 12-07 which allows other comprehensive walkdowns conducted within 2011 and 2012 to be credited for validation of flood protection features.

Theseother walkdowns may be credited if the walkdown was performed and documented such that metthe expectations in this guideline.'

Many of the items on the Flood Feature list were walkeddown within the past year. In order to ensure that the scope of these previously performed walkdowns met the intent of NEI 12-07's guidance, a gap analysis was performed.

Features that were not walked down went through an intensive review of their PM programs, testing programs, and surveillance programs.

None of these items were categorized as restricted or inaccessible.

Features that were subject to controlled PM programs were evaluated to ensurethat there was reasonable assurance of continued functionality.

This information wasdocumented in the walkdown records and has been summarized in this report. Even thoughsome of the features were not walked down specifically for this exercise, the following activities were performed for each feature on the list:* Ensured that the feature is included in a periodic test, monitoring, or inspection program* Verified that the testing, monitoring, or inspection is being performed

• Determined if the scope of the test, monitoring, or inspection is adequate to confirm thecredited flood protection function of the feature.Any questionable observations were entered into PIP for disposition or were already in PIP andthose PIP's were referenced.

Additionally, all features on the list have been walked down thisyear, although not necessarily for this specific exercise.

All walkdowns, were performed bySubject Matter Experts (SME's) either in CiVil or Mechanical design groups. These walkdowns were comprehensive in scope, looking specifically for degradation of features and signs ofleakage.

After reviewing the scope of each walkdown, all have been found to be acceptable inmeeting the intent of NEL 12-07. Therefore it was determined that the provisions of Section 5.5of NEI 1.2-07 were satisfied, and a re-performing a walkdown of these features would not beconducted.

Since Oconee's walkdown scope was relatively

limited, it was decided that the minimumrequired participants could implement the task.* Adam Johnson was chosen to be the lead engineer on the Flood Walkdowns.

Hisbackground is based in the Civil Design Basis group. He was selected due to his priorPage 20 Flood Walkdown Report -NRC 50.54 (f) NTTF Recommendation 2.3WitbhIOlo from puD~lC uI(Isiill-U llUr = Juma ,,-AU ..~F ... O~J1/41knowledge of ONS licensing basis for flooding, and walkdown experience of current sitefeatures.

• Jim Weir was selected as the second walkdown team member. His background includesowning many different systems on site, as well as being a part of investigation teams inthe past. He was selected based on his wealth of experience on site at ONS and hismechanical engineering background.

This provided diversity to the walkdown team toprotect against "group think" pitfalls.

This team satisfied the requirements of Section 5.3 of NEI 12-07, which includes requirements for knowledge of site current licensing basis, and experience with visual inspections of plant.SSC's. The guidance outlined inl Table 1 of Appendix C to NEI 12-07 was fully met and wasdocumented in the training portion of the Walkdown package.

The walkdowns werespecifically scheduled to avoid being performed simultaneously with other routine activities.

Some additional personnel accompanied the walkdown team, but their scope was limited toregular maintenance activities, such as opening cabinets.

An OPS trained expert contributed tothe Abnormal Procedure walkthr'ough and External Flood Mitigating Guidance Documentwalkthrough.

A primary system engineer who authored the External Flood Mitigation Documentalso participated in the External Flood Mitigating Guidance Document walkthrough.

Section 7 of NEI 12-07 describes the peer review process for the flood walkdowns.

Instead ofobtaining a completely independent peer review, the walkdown forms have sign offs thatconstitute a peer review. Completion of the review signatures on the walkdown forms ensuresthe intent of the peer review, as described in NEI 12-07, was met. The walkdown forms withpeer review signatures are retained as an attachment to the calculation that documents thewalkdown results.

ONS has not taken exception to the NEI 12-07 process and no actionsresulted in a change to the walkdown process or methodology.

5.4 RESULTS OF WALK.DOWNS Based on the guidance of NEI 12-07, the walkdown process Was implemented for 11l floodfeatures.

The other flood features were accessed based on prior work and walkdowns completed within 2011 and 2012. The flood walkdowns, as directed and defined by NEI 12-07, onlyresulted in the finding of one deficiency.

This deficiency is the out of service voltmeters locatedat the Keowee Spillway gates. By being out of service they cannot meet their intended designfunction, which is to monitor the voltage being used by the gate motors. This deficiency doesnot affect that actual operation of the spillway gate, but since the voltmeters are a NRCcommitted item and a FERC requirement, they are being described as a deficiency.

There are nooperability concerns due to this deficiency.

This deficiency is documented in PIP. Operators still have the ability to manually connect volt meters to read voltage during gate operation.

Thevolt meters are scheduled to be returned to service by the end of 2012. This deficiency was theonly item requiring a reportability review in accordance with Regulatory Issues Summary 2005-20, R~ev 1, Revision to NRC Inspection Manual Part 9900 Technical

Guidance, "Operability Conditions Adverse to Quality or Safety,"

to ensure that ONS was in compliance with ourreportability process.Page 21 Flood Walkdown Report -NRC 50.54 (f) NTTF Recommendation 2.3wtI~lnnoI iromi pU Iubih, u: n .... ........1 ~ l .,_,(_)(Other PIP's were written in conjunction with the walkdowns.

The scope of these PIP's rangefrom missing Foreign Material Exclusion (FME) covers to PM program weaknesses.

A briefdescription of each of the PIP's written is shown below for completeness.

1. During Flood procedure walkdown (AP-47) an obstruction was noted at one of the EFMFire Hose Anchor Points.2. AP/0/A/1 700/047 needs enhancement in description of site personnel evacuation of lowlying areas due to External Flood.3. AP/0/A/1700/047 needs enhancement on instruction to SSF operators to safely evacuateto higher ground as the flood waters over top the SSF exterior flood walls. Currentprocess may put operators in an unnecessary personal safety risk.4. The hard copy of Enclosure 5.5 of AP/0/A/1 700/047 that is "procedure staged" in theEFM trailer was found wet in its protective covering.

5. AP-47 reasonable simulation exercise associated with NRC 50.54(f)

Flood Walkdownactivities raised questions regarding Nuclear Equipment Operator (NEO) activities vs.NEOs on minimum staff.6. The EFM Hale Pump located at CTP-1 (based on oil in the Oil catchment) had a small oilleak. Also suction and discharge hoses need FME covers.7. Cosmetic degradation of the concrete construction joint at the East wall and Floor Slab ofSSF. Minor hairline cracking noticed in the grout pad of Exterior Flood Wall Support inPatio area.8. Weaknesses discovered with EFM/Extensive Damage Mitigation (EDM) Hale Pump FireHose inspection and testing PMs.9. During AP-47 field walkdowns at CTP-1, Precautions and Enhancements regarding thePump Suction Pipe were identified.

10. Observation during AP-47 walkdowns regarding the potential impact of debris floating inCTP-1 water on the Hale Pump Suction Strainer.

11. A deficiency has been identified during the flood walkdowns.

The Voltmeters at theKeowee Spillway were found out of service and had inadequate procedural direction.

A list of the features that were walked down for this report are listed below:Feature #17: reasonable simulation.

Some issues were found while performing thissimulation.

Feature #18: reasonable simulation.

Some issues were found while performing thissimulation.

None of these issues were deemed to cause the procedures to benon-effective.

Feature #23: inspected.

A deficiency was discovered.

Page 22 Flood Walkdown Report -NRC 50.54 (f) NTTF Recommendation 2.3CO.'lTAi.!.fl fECUI.I'IT'.

2ErJ2TTr:r.

Feaur #2: nspctd.ItJ~

was found toUEI beLI~U copetl UIacceptable Feature #24: inspected.

It was found to be completely acceptable.

Feature #25: inspected.

It was found to be completely acceptable.

Feature #26: inspected.

It was found to be completely acceptable.

Feature #28: inspected.

It was found to be completely acceptable.

Feature #30: inspected.

Issues were found with this item but these were not deficiencies.

Feature #32:inspected.

It was found to be completely acceptable.

PIP's were written todiscuss issues found during this walkdown.

These were either cosmetic ofhousekeeping issues and did not directly relate to the features ability to performits function.

Feature #33: inspected.

It was found to be completely acceptable.

Other PIP's were referenced in the walkdown forms for the items not walked down. Many of thefeatures had previously been walked down within 2012 and ONS elected to not perform reworkby re-walking these features down. Some issues exist with these features.

Listed below are theflood features that were not re-inspected.

Feature # 1Feature #2Feature #3Feature #4Feature #5was not reinspected, but also not completely acceptable.

Issues currently existwith the Aux building below grade penetrations.

PIP' s have been written totrack the issues with Feature # 1.was not reinspected, but also not completely acceptable.

Issues currently existwith the Radwaste trench covers to the turbine building.

PIP's have been writtento track the issues with this feature.was not reinspected, but, also not completely acceptable.

Issues currently existwith the Radwaste trench covers to the auxiliary building.

PIP's have beenwritten to track the issues with this feature.was not reinspected, but also not completely acceptable.

Issues currently existwith the Interim Radwaste trench covers to the auxiliary building.

PIP's havebeen written to track the issues with this feature.was not reinspected, but also not completely acceptable.

Issues currently existWith Manhole 7. PIP's have been written to track the issues associated with thisfeature.Feature #6 was not reinspected, and was found completely acceptable.

Feature #7was not reinspected, but also not completely acceptable.

Issues currently existwith the yard drain system. PIP's have been written to track the issuesassociated with the yard drain system.Page 23 Flood Walkdown Report -NRC 50.54 (f) NTTF Recommendation 2.3Features

1. 8 thrul 6, #1 9 thru 22, #27, and #31 were not re-inspected, and were foundcompletely acceptable.

Feature #34 was not reinspected, but also not completely acceptable.

Issues currently existwith the below grade SSF penetrations.

PIP's have been written to track theissues with this feature.Feature #35 was not reinspected, but also not completely acceptable.

Issues currently existwith the Site Elevation and Topography.

PIP's have been written to track theissues with this feature.There were no flood features identified as restricted access or inaccessible feature.

All featuresthat were originally identified as CLB flood features were successfully walked down.There were no Cliff Edge Effects entered into PIP. Cliff Edge Effects as defined by NEI 12-07and the NRC's Near Term Task Force (NTTF) Report are: issues with the plant where "thesafety consequences of a flooding event may increase sharply with a small increase in theflooding level." At ONS there is a postulated flood elevation of 815' ft msl. This is a flood ofapproximately 19' in the yard at some areas. Many structures are assumed to be completely flooded and fail. Cliff Edge Effects differ from Available Physical Margin (APM). The APMfor each applicable flood protection feature is the difference between licensing basis flood heightand the flood height at which water could affect an SSC important to safety. Determination ofAPM for local intense precipitation may not be possible.

The APM information for the featureslisted above has been collected and can be found on the Walkdown Forms. This information willbe used in the flood hazard reevaluations performed in response to Item 2.1: Flooding in the50.54(f) letter.Prior to starting the NTTF 2.3 Flood walkdowns, ONS had initiated detailed research for boththe Jocassee Dam Break scenario as well as the PMP flooding scenario.

Since the release of theNRC 50.54(f) letter ONS has had to reprioritize the design scope and schedule for its plannedmodifications to the plant to mitigate these different flooding scenarios.

In accordance with thedirection from Recommendation 2.1 Flooding from the NRC 50.54(f) letter, the ONS site floodhazards are currently being reanalyzed.

Based on the results of this effort, new flood mitigating features will be designed and installed.

However, based on the results of the 2.3 floodwalkdowns, no immediate

changes, other than those described above in the PIP system, will bemade to ONS.6.0 Compliance with NEI! 12-07, Appendix DThe outline below was created to ensure the report above accommodates recommendations from,and is in full compliance with, NEI 12-07 appendix D. Each section of NEI 12-07 Appendix Dis presented below with a page and section reference from the report above that fulfills its intent.The items in italics are excerpts from NET 12-07.Page 24 Flood Waikdown Report -NRC 50.54 (f) NTTF RecOmmendation 2.3a. Describe the design basis flood hazard level (s) for all flood-causing mechanisms, including groundwater ingress.*Identify all flood hazards that were evaluated in the site 's design basis and the floodlevel resulting from each. Identify hazards that were screened out.i. Note that some flood hazards may be limiting for flood level and some for otherconsiderations such as warning time and dynamic loading.Two flood hazards were identified.

These hazards are the PMP flood event described inSection 5.1.1.1 and the Sunny Day Failure of Jocassee Dam described in Section 5.1.2.No hazards were screened out because Oconee's only external flooding events are thePMiP and Jocassee Dam Break. Groundwater ingress is not a design or licensing basisflood hazard at Oconee, therefore this hazard was screened out.*Describe any key assumptions (e.g., all culverts were assumed blocked)No assumptions were made in this report. This is described in Section 4.* Include information on the methodology used in developing the design basis floodinghazardNo specific methodologies are described for the ONS PMP flood hazard as originally described in the UFSAR. Currently, HEC-RAS based models are being performed to addressthe PMP flood hazard reanalysis.

Methodologies for determining the Jocassee Dam Breakhazard are described in Section 5.1.2.*If differences or" contradictions in flood hazard levels were found in design orlicensing basis documentation, include a description of the basis for flood level usedAs flood models develop further for the Jocassee Dam Break and the PMIP flood event, newflood levels are obtained.

The flood levels described in the Safety Evaluation provided by theNRC for the Jocassee Dam Break scenario represent current design basis for the JocasseeDam Break. The original PMP flood hazard as described in the UFSAR represents thecurrent design basis for PMP flood.b. Describe protection and mitigation features that are considered in the licensing basisevaluation to protect against external ingress of water into SSCs important to safety.*Describe the flooding licensing basis including what plant configurations (modes ofoperation; for example.

full power operations, start up, shutdown, and refueling) wereconsidered This description should be consistent with the scope of the floodingwalkdowns.

Oconee's flooding licensing basis includes two flooding events previously described:

thePMP flood and the Jocassee Dam Break. Neither event takes into consideration modes ofoperation.

These events are assumed to occur with minimurn required operating staff..Page 25 Flood Walkdown Report -NRC 50.54 (f) NTTF Recommendation 2.3-.T?_IBJ LYNETINFORMATION.

Document the flood duration assumed in the CLB. If the CLB does not provideinformation on the flood duration, this lack of information should be documented inthe walkdlown report.The PMP flood event is a 48 hour5.555556e-4 days <br />0.0133 hours <br />7.936508e-5 weeks <br />1.8264e-5 months <br /> event as described in section 5.1.1.1.

The Jocassee DamBreak event produces modeled flood levels in the Oconee yard f[or approximately 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br />, asdescribed in Section 5.1.2.* Describe the flood prote ction features that are credited in the CLB, such asincorporated, exterior and temporar~y

barriers, time required for credited actionsunder flood conditions, active flood protection

features, procedures, warningscredited for external floods, site drainage plan, etc..The descriptions of the flood protection features that are credited in the CLB are located inSection 5.2. These descriptions make up a large portion of the report.* Describe weather conditions or flood levels that trigger procedures and associated actions for providing flood protection and mitigation.

The weather conditions that initiate the PMP flooding event are described in theOconee Severe Weather Preparations procedure.

Specifically these conditions include a rainfall in excess of 4 inches of rain in any 6 hour6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> period. This procedure dictates actions to be taken prior to the weather event arriving.

This is described inSection 5.1.I.1.*Describe the adverse weather conditions that were assumed concurrent with floodprotection features and associated actions.No other adverse weather conditions are assumed to occur concurrently with the floodprotection features are associated actions.

This is described in Sections 5.1.I. 1 and 5.1.2.c. Describe any warning systems to detect the presence of wafer in rooms important tosafety.*Describe the room water level warning systems (e.g., alarms) credited for their floodprotection function in the plant 's externaliflooding licensing basisNo room water level warning systems are credited for flood protection in the plants externalflooding licensing basis. This is described in Section 5.2.6.* Note that systems that detect internal flooding sources are not part of the scope of thewalkdownd. Discuss the effectiveness of flood protection systems and exterior, incorporated, andtemporary flood barriers.

Discuss how these systems and barriers were evaluated usingthe acceptance criteria developed as part of Requested Information Item J.h.Page 26 Flood Walkdown Report -NRC 50.54 (f) NTTF Recommendation 2.3 C " C,, fl,, .IT ......... r1n.F MAT

• The purpose of the 2.3 walkdowns is to verif the conformance with the CLB; theadequacy of the CLB will be addressed as part of the 2. 1flood ree valuations if anintegrated assessment is requiredAll flood protection features were analyzed based on their licensing basis function.

This isdescribed in Section 5.2.* The acceptance criteria for the walkdowns are described in section 6 of the guideline.

This approach is consistent with requested information item 1. h of the 50.54(f) letter.Discuss how the plant implemented this approach.

Oconee implemented the acceptance criteria as described in Section 6 of the NEI 12-07guideline.

Section 5.3 describes Oconee's walkdown process and the implementation of theNEI 12-07 guidelines.

• This discussion should include an evaluation of the overall effectiveness of the plant 'sflood protection features to perform their credited functions during a variety of siteconditions (as defined previously,),

as determined by the results of the walkdowns (thefeatures are available, functional, and implementable).

The CAP process willdetermine which of the walkdown observations are deficiencies and what actionswere taken or planned to address them. Questions such as the jollowing should beevaluated for a variety of site conditions:

The overall effectiveness of the features is described in Section 5.2.i. ls the barrier system functional

?All features were either deemed acceptable (functional) or the issues were identified asdeficiencies.

ii. Are operator actions feasible?

The reasonable simulations that were performed are described in Section 5.2.4. Operatoractions were deemed feasible.

• Describe how other existing plant equipment, structures, and procedures mightmitigate the effects of fan external flood under a variety of plant configurations.

Oconee has specific mitigating plans for the licensing basis hazards.i.Clearly describe what additional

existing, if any, plant structures, systems,components, and procedures that are not part of the flooding CLB and that couldbe used to mitigate an external flood. Note that the Walkdown Report shouldinclude a description of existing plant capability, not an assessment of plantvulnerabilities to flooding that might exist under all susceptible plantconfigurations.

The assessment of plant vulnerabilities to all. susceptible plantconfigurations will be completed, if applicable, as part of an Integrated Assessment peiformed in response to Enclosure 2 of Reference 1Page 27 Flood Walkdown Report -NRC 50.54 (f) NTTF Recommendation 2.3-.ijL i..... * -.L i.. ,it.., ......J 0 i There are a few features onsite that could be used to mitigate an external flood and arenot part of the ONS CLB. These features are described in Section 5.2.5.ii. Note: NUMARC 93-01, Rev 4A provides guidance on implementation of themaintenance rule. Section 11.3. 4. 2 of this document recommends an assessment of maintenance activities that expose SSCs to flood hazards in a mlanner thatdegrazdes their capability to perform key safety functions.

Credit for this activitycould be included in this discussion.

All flood mitigating features that might be affected by maintenance activities are listed asOconee PasSive Design Features.

Items included on the Passive Design Feature listreceive an extra level of oversight to ensure we do not degrade their capability to performkey safety functions.

This is described in Section 5.2.1 .e. Present information related to the implementation of the walkdown process.

(e.g., detailsof selection of the walkdown team and procedures,)

using the documentation temnplate discussed in Requested Information Item 1.j, including actions taken in response to thepeer review.Confirm that guidance was followed (and options selected when available within theguidance) and any exceptions taken to the guidance.

See sections

5. 3 7, Appendix B.NEt 12-07 was followed and no exceptions were taken to the guidance.

This is described inSection 5.3.* Describe how the walkdlown teams were organized (e.g., number of members, generalbackground, etc.). See sections 5.3 and 7.There was only one walkdown team consisting of two members.

The walkdown members andtheir backgrounds are described in Section 5.3.*Describe the approach used to comply with section 5.3 guidance on Walkdown teamselection and training.

The waikdown team was in full compliance with the training requirements set forth by NEt12-07. This is described in Section 5.3.f. Results of the ,walkdown including key findings and identijfied

degraded, non-conforming, or unanalyzed conditions.

Include a detailed description Of the actionstaken or planned to address these conditions using the guidance in Regulatory IssuesSummary 2005-20, Rev 1, Revision to NRC Inspection Manual Part 9900 Technical

Guidance, "Operability Conditions Adverse to Quality or Safety,"

including entering thecondition in the corrective action program.Include the following items* Description of all deficiencies-as determined by the CAP. Observations that areentered into the CAP and not dispositioned as deficiencies do not need to be. reporte~d Page 28 Flood Walkdown Report.-

NRC 50.54 (f) NTTF Recommendation 2.3~NTA1N3 JE2UflITY fTNfiITI"E VN!~f~W~

l~A Awflnnppu ii ujip p.uuii~ .IL~i.....J.. 10 --,flr ,, 2 n.1 ,.,d I 1.One deficiency was identified and was entered into PIP. This is described in Section 5.4.* Description of any observations reported in the CAP that were not dispositioned atthe time of the report "All observations that were entered into the Corrective Action program were dispositioned atthe time of the report.* Describe actions that were taken or are planned to address the deficiencies using theguidance in RegUlatory Issues Summary 2005-20 Revision 1.The guidance in RegulatorY issues Summary 2005-20, Revision

! was taken intoconsideration for the deficiency that was discovered.

This is described in Section 5.4.*Flood protection features that could not be inspected, including All flood features were inspected.

No items were Categorized as restricted access orinaccessible.

This is described in section 5.4. The sub-items below are not applicable o Features affected by restricted access (see section 5. 1):-Justi~fication for delay-Schedule-Any necessary special procedures o Inaccessible features (see section 5.1J%"-Basis for reasonable assurance that the feature is available and will performits credited function or an assessment of the impact of non-peiformance of thefunctionl f more than one "'inaccessible "flood protection feature wvith potential loss offunction is reported, then an evaluation of the aggr'egate effect floodprotection features must be provided.

• Walkdown record forms are not submitted to the NRC, but as discussed in Section 7are retained onsite for NRC inspection The walkdown forms have been retained onsite and can be accessed for NRC inspection asdescribed in Section 1.0.g. Document any cliff-edge effects identified and the associated basis. Indicate those thatwere entered into the corrective action program.

Also include a detailed description ofthe actions taken or planned to address these effects.*Cliff edge effects and physical margins do not need to be rePorted to the NRC as partof the Walkdown Report. However, the Alppendix B walkdown

records, which include.the collected 4PM information, need to be retained and caailable for NRC audits andinspections.

page 29 Flood Walkdown Report -NRC 50.54 (f) NTTF Recommendation 2.3WIlfnfloIu iruuz puwlIt uul:.auiuuul uniit.~ .. .-,u ' ,.The walkdown forms have been retained onsite and can be accessed for NRC inspection asdescribed in Secti6rn 1.0.. ..*. While the NRC used the same term :as the NTTF Report in its 50. 54(0) information request (Reference 8.1) related to Flooding Recommendation

2. 3, the information that the NRC expects Utilities tO obtain during the Recommendation 2.3 walkdowns is /different.

To clarify, the NRC is now differentiating between cliff-edgel effects (whichare dealt with in Recommendattion 2.1) and a new term, Available Physical Margin(APM). APM information will be collected during the walkdowns, but will not bereported in the response to Reference 8.1, Enclosure

4. The APMs determined by theRecommendation 2.3 walkdowns do not involve calculating the cliff-edge effects (i. e.,the safety consequences).

During the Recommendation 2.1i integrated assessment, thecliff-edge effects and the associated safety risks will be determined using the APMs aswell as other information, such as the specific SSCs that are subjected to flooding andthe potential availability of other systems to mitigate the riskAPM information has been collected.

This is described in Section 5.4.l nstead of submitting cli4ff-edge effects report that Available Physical Margins ihavebeen collected and documented in the Walkdown Record fi~rm (Appendix B). Thisinformation will be used in the flood hazard reevaluations performed in response toItemn 2.1: Flooding in the 50.54(1) letter (Reference 8.1!).Cliff edge effects are not being submitted.

Available Physical Margins have been collected and documented.

This is described in Section 5.4.h. Describe any other planned or newly installed flood protection systems or floodmitigation measures including flood barriers that further enhance the flood protecetion.

Identify results and any subsequent actions taken in response to the peer review.* Describe changes determined to be necessary by the flood walkdowns and whetherthey have been completed or their schedule for completion No other changes, other than those already initiated in the ONS CAP, will be made. This isdescribed in Section 5.4.* For the purposes of the flooding design basis walkdown verifi cation, the peer reviewis the process described in section 7. The only actions and results that should be:reported are those that r'esulted in a change to the iwalkdown process or methodology.

Corrections and resolution of differences resulting from the normal process ofperformer

/ reviewer interaction are not repoQrted The peer review process as described in Section 7 of NEi 12-07 has been followed..

Nochanges have been made and therefore there are no reportable actions.

This :is described inSection 5.3.Page 30