ML20366A012
| ML20366A012 | |
| Person / Time | |
|---|---|
| Issue date: | 12/29/2020 |
| From: | NRC/OCIO |
| To: | |
| Shared Package | |
| ML20366A007 | List: |
| References | |
| FOIA, FOIA/PA-2017-0690, NRC-2017-000688 | |
| Download: ML20366A012 (48) | |
Text
Charles R. Pierce Southern Nuclear Regulatory Affairs Director Operating Company, Inc.
40 Inverness Center Parkway Post Office Box 1295 Birmingham, AL 35242 Tel 205.992.7872 Fax 205.992.7601 SOUTHERt.'
NUCLEAR
<<\
A SOUTHERN COMPANY Stt I i 2015 Docket Nos.: 50-348 NL-15-1222 50-364 U. S. Nuclear Regulatory Commission ATTN: Document Control Desk Washington, D. C. 20555-0001 Joseph M. Farley Nuclear Plant - Units 1 and 2 Recommendation 2.1 Flood Hazard Reevaluation Report
References:
- 1. NRC Letter, Request for Information Pursuant to Title 10 of the Code of Federal Regulations 50.54(f) Regarding Recommendations 2.1, 2.3, and 9.3, of the Near-Term Task Force Review of Insights from the Fukushima Daiichi Accident; dated March 12, 2012.
- 2. Letter to NRC, Southern Nuclear Operating Company Request to Obtain U.S. Army Corps of Engineers (USAEC) Information, dated September 26, 2013. (ML13274A343)
- 3. Letter to NRC, Joseph M. Farley Nuclear Plant - Units 1 and 2 Request for Extension of Flood Hazard Reevaluation Report Due Date, dated February 28, 2014. (ML14072A486)
- 4. Letter to NRC, Joseph M. Farley Nuclear Plant - Units 1 and 2 Additional Information Regarding the Request for Extension of Flood Hazard Reevaluation Report Due Date, dated May 21 , 2014. (ML14141A629)
- 5. Letter from NRC, Joseph M. Farley Nuclear Plant - Units 1 and 2, Relaxation of Response Due Dates Regarding Flood Hazard Reevaluations for Recommendation 2.1, dated July 17, 2014. (ML14174A938)
- 6. NRC Letter, Joseph M. Farley Nuclear Plant, Units 1 and 2 - Transmittal of U.S. Army Corps of Engineers Flood Hazard Reevaluation Information, dated June 25, 2015. (Ml151768199)
Ladies and Gentlemen:
On March 12, 2012, the Nuclear Regulatory Commission (NRC) issued Reference 1 to all power reactor licensees and holders of construction permits in active or deferred status. Enclosure 1 of Reference 1 requested each addressee perform and submit a Flood Hazard Reevaluation Report (FHRR).
In order to fully perform this reevaluation for the Joseph M. Farley Nuclear Plant (FNP) site, Southern Nuclear Operating Company (SNC) submitted Reference 2 requesting specific
U. S. Nuclear Regulatory Commission NL-15-1222 Page 2 information be obtained by the NRC from the U.S. Army Corps of Engineers (USACE) and be provided to SNC. To meet all of the requirements of Reference 1, SNC submitted Reference 3 which outlined the need for an extension request to provide the FHRR 120 days after the USACE flooding analysis information was received. SNC also provided additional information requested by the NRC by Reference 4. The NRC granted the requested relaxation as provided in Reference 5.
On June 25, 2015, the NRC provided the requested information (Reference 6) which started the agreed upon 120 day clock. The Flooding Hazard Reevaluation Report for FNP is provided in the Enclosure to this letter. This completes the flooding hazard reevaluation for FNP as required by Reference 1.
This letter contains no new regulatory commitments. If you have any questions, please contact John Giddens at 205.992.7924.
Mr. C. R. Pierce states he is the Regulatory Affairs Director for Southern Nuclear Operating Company, is authorized to execute this oath on behalf of Southern Nuclear Operating Company and, to the best of his knowledge and belief, the facts set forth in this letter are true.
R**t;"f);::d, C.R. Pierce Regulatory Affairs Director CRP/JMG/GLS Sworn o and subscribed before me t h i s ~ day of {J!)cJ.v RM I 2015,
-=--+-=::..:::....,___........=..+-:-*Ht-Notary Public My commission expires: / {) ':Z -Zo /1
Enclosure:
Joseph M. Farley Nuclear Plant - Units 1 and 2 Flood Hazard Reevaluation Report cc: Southern Nuclear Operating Company Mr. S. E. Kuczynski, Chairman, President & CEO Mr. D. G. Bost, Executive Vice President & Chief Nuclear Officer Ms. C. A. Gayheart, Vice President - Farley Mr. M. D. Meier, Vice President- Regulatory Affairs Mr. B. J. Adams, Vice President - Engineering Mr. D.R. Madison, Vice President - Fleet Operations RTYPE: CFA04.054
U.S. Nuclear Regulatory Commission Nl-15-1222 Page3 U. S. Nuclear Regulatory Commission Mr. L. D. Wert, Regional Administrator (Acting)
Mr. S. A. Williams, NRR Project Manager - Farley Mr. P. K. Niebaum, Senior Resident Inspector- Farley Alabama Department of Public Health Dr. D. E. Williamson, State Health Officer
Joseph M. Farley Nuclear Plant - Units 1 and 2 Recommendation 2.1 Flood Hazard Reevaluation Report Enclosure Joseph M. Farley Nuclear Plant Units 1 and 2 Flooding Hazard Reevaluation Report
FLOOD HAZARD REEVALUATION REPORT IN RESPONSE TO THE S0.54(f) INFORMATION REQUEST REGARDING SEVERE ACCIDENT MANAGEMENT FOR FUKUSHIMA NEAft..TERM TASK FORCE RECOMMENDATION 2,1: FLOODING REEVALUATION for the JOSEPH M. FARLEY NUCLEAR PLANT 7388 ALABAMA 9S, COLUMBIA, ALABAMA 36319 Renewed Facility Operating License Nos. NPF-2 (Unit 1) and NPF-8 (Unit 2)
NRC Docket Nos. S0-348 (Unit 1) and 50-364 (Unit 2)
Southern Nuclear Operating Company, Inc.
42 Inverness Center Parkway, Bin 8044 P.O Box 1295 Birmingham, Alabama 35201-1295 Prepared by:
AMEC Environment & Infrastructure, Inc.
3800 Ezell Road, Suite lOD Nashville, Tennessee 37211 Version 1.0 Printed Name Affmation .Q.!N Originator: iit.,-1 e~El.\."-l- AMEC
'o/t,V~
Verlfler: *- :J'~s '6~=s.s____ AMEC
/C) /l.lJ Jz_.o/
Approver: ~.t+r A. m~(\ t"l AMEC
- : x = t ~ ~ ~ ~ JIJ /1-0 '2.01 Lead Responsible Engineer: -r 1
_d0.!::_\~
- !' / ,* ,.
- 4'C'ftAIC:"" I -*- 5/VC _
Branch Manager senior Manager Design Engineering:
Corporate Acceptance; '4Hfli 1t,AEr/ .S SNC PO No.: SNA31945-0002, Line 1, Item 764659 RCN: FAR0169.0
SAM NTTF Recommendation 2.1 (Hazard Reevaluations): Flooding October 20, 2015 Southern Nuclear Operating Company, Inc. Version 1.0 Contents
- 1. LIST OF ACRONYMS .................................................................................................................................... 4
- 2. PURPOSE .................................................................................................................................................... 5
- a. Background ............................................................................................................................................ 5
- b. Requested Actions ................................................................................................................................. 6
- c. Requested Information .......................................................................................................................... 6
- 3. SITE INFORMATION .................................................................................................................................... 7
- a. Detailed Site lnformati,on ....................................................................................................................... 7
- b. Current Design Basis Flood Elevations for All Flood Causing Mechanisms.......................................... 15
- c. Flood Related Changes to the Licensing Basis and Any Flood Protection Changes (including mitigation) Since License lssuance ............................................................................................................... 18
- d. Changes to Watershed and Local Area since License Issuance ........................................................... 19
- e. Current Licensing Basis Flood Protection and Pertinent Flood Mitigation Features ........................... 19
- f. Additional Site Details .......................................................................................................................... 20
- 4.
SUMMARY
OF FLOOD HAZARD REEVALUATION ...................................................................................... 21
- a. Local Intense Precipitation ................................................................................................................... 21
- b. Flooding in Streams and Rivers ............................................................................................................ 27 Chattahoochee River................................................................................................................................ 27 Wilson Creek ............................................................................................................................................ 27
- c. Dam Breaches and Failures .................................................................................................................. 29
- d. Storm Surge .......................................................................................................................................... 31
- e. Seiche ................................................................................................................................................... 31
- f. Tsunami ................................................................................................................................................ 31
- g. Ice Induced Flooding ............................................................................................................................ 32
- h. Channel Migration or Diversion ........................................................................................................... 32
- i. Combined Effect Flood ......................................................................................................................... 36 Kontek Vehicle Barrier ............................................................................................................................. 36 Wind-Generated Waves ............................................................................................................................ 37
- 5. COMPARISON WITH CURRENT BASIS FLOOD HAZARD ............................................................................ 38
- 6. INTERIM EVALUATION AND ACTIONS TAKEN OR PLANNED TO ADDRESS ANY HIGHER FLOODING HAZARDS RELATIVE TO THE DESIGN BASIS ...................................................................................................... 39 LIP ............................................................................................................................................................. 40 Riverine PMF ............................................................................................................................................ 40
- 7. REFERENCES ............................................................................................................................................. 41 JOSEPH M. FARLEY NUCLEAR POWER PLANT Page 2 of 44 SNC PO No.: SNA31945*0002, Line 1, Item 764659 RCN: FAR0169.0
SAM NTTF Recommendation 2.1 (Hazard Reevaluations): Flooding October 20, 2015 Southern Nuclear Operating Company, Inc. Version 1.0 List of Tables Table 3-1: Chattahoochee River Significant Reservoirs ...........................................................................................12 Table 3-2: Land Cover for the Chattahoochee River Watershed ..................................................................... 12 Table 4-1: 1-hr/1-sq-mi PMP Distribution for Plant Farley .............................................................................. 23 Table 4-2: LIP Predicted Flooding Results at the Main Doors and Bays................................................................ 25 Table 4-3: PMF Peak Dischar es at the Wilson Creek HEC-HMS Model Junctions ............................................ 28 Table 4-4: (b)(3) 16 USC § 8240 1(d), (b)(4) (b)(7)(F) ........................................................................................ 30 Table 4-5: Summary of Key Wave Characteristics ...................................................................................................37 Table 5-1: Summary Comparison with Current Licensing Basis Flood Hazard ....................................*.................38 Table 6-1: River Stages and Preparation Time..........................................................................................................40 List of Figures Figure 3-1: Site Location of Plant Farley (USGS Quadrangle Reference llc) .................................................... 9 Figure 3-2: Site Layout and Topography of Plant Farley (Reference 19) ......................................................... 10 Figure 3-3: Chattahoochee River Watershed ............................................................................................................ 11 Figure 4-1: 1-hr PMP Distribution for Plant Farley .......................................................................................... 23 Figure 4-2: Discharge and Stage Hydrograph for a PMF on the Chattahoochee River Routed through Walter F. George using Controlled Releases..........................................................................................................................27 Figure 4-3: Wilson Creek Watershed..........................................................................................................................28 Figure 4-4: Water Surface Elevation Profile for Governing PMF from Wilson Creek HEC-RAS Model... .......... 29 Fi ure 4-5: Dischar e and Sta e Hydrograph for Governing PMF from (b)(3) 16 us C § 824o-1(d) (b)(4)
F O*
ydrolog1c a1lure at I
- f * ..... - i b F
........................ ..,............,,,_,,,,,,,_,_,,_,,:__,_,:__ § )(3) 16l(d)
USC.
(b) 8240 1gure - : ot an, Quadrangle Map ...............................................................................................33 (4) (bi?)(F)
Figure 4-7: 2011 NAIP Aerial lmagery.........................................................................................................................34 Figure 4-8: Superposition of 1953 USGS Quandrangle Map on 2011 NAIP Aerial lmagery................................35 Figure 4-9: 2011 USGS Gordon, AL*GA 7.5' Quadrangle Map.................................................................................36 JOSEPH M. FARLEY NUCLEAR POWER PLANT Page 3 of 44 SNC PO No.: SNA31945-0002, Line 1, Item 764659 RCN: FAR0169.0
SAM NTTF Recommendation 2.1 (Hazard Reevaluations): Flooding October 20, 2015 Southern Nuclear Operating Company, Inc. Version 1.0
- 1. LIST OF ACRONYMS oc degree(s) Celsius (or Centigrade)
OF degree(s) Fahrenheit ac acre(s)
ANS American Nuclear Society ANSI American National Standards Institute APM Available Physical Margin CAP Corrective Action Program CFR Code of Federal Regulations cfs cubic (foot)feet per second CLB Current Licensing Basis CR Condition Report D-A-D depth-area-duration (curves)
DEM Digital Elevation Model EM Engineer Manual ESP Early Site Permit ESRI Environmental Systems Research Institute ft feet FEMA Federal Emergency Management Agency FFE Finish Floor Elevation FSAR Farley Nuclear Plant Final Safety Analysis Report FTP file transfer protocol GIS Geographic Information System GHCN Global Historical Climatology Network GHCND Global Historical Climatology Network Data HEC Hydrologic Engineering Center HEC-HMS Hydrologic Engineering Center Hydrologic Modeling System HEC-RAS Hydrologic Engineering Center River Analysis System HHA hierarchical hazard assessment HMR Hydrometeorological Report hr hour(s)
HUC Hydrologic Unit Code in inch ISFSI Independent Spent Fuel Storage Installation km kilometer(s) km 2 square kilometer(s)
LandSat Land-Use Satellite m meter(s) mi2 square mile(s) mi mile(s) min minute(s) mm millimeter(s)
JOSEPH M. FARLEY NUCLEAR POWER PLANT Page 4 of 44 SNC PO No.: SNA31945-0002, Line 1, Item 764659 RCN: FAR0169.0
SAM NTTF Recommendation 2.1 (Hazard Reevaluations): Flooding October 20, 2015 Southern Nuclear Operating Company, Inc. Version 1.0 NAIP National Agriculture Imagery Program NAVD88 North American Vertical Datum of 1988 (NGV029 - 0.33 ft)
NCDC National Climatic Data Center NED National Elevation Dataset NGVD29 National Geodetic Vertical Datum of 1929 {Mean Sea Level)
NHD National Hydrography Dataset NLCD National Land Cover Database NOAA National Oceanic and Atmospheric Administration NRC United States Nuclear Regulatory Commission NRCC Northeast Regional Climate Center NRCS Natural Resources Conservation Service NWS National Weather Service PMF probable maximum flood PMP probable maximum precipitation PPT Precipitation depth PMSA Probable Maximum Snowpack Accumulation PSAR Preliminary Safety Analysis Report RWST Refueling Water Storage Tank scs Soil Conservation Service SNC Southern Nuclear Operating Company SSCs structures, systems, and components SSE safe shutdown earthquake UFSAR Updated Final Safety Analysis Report USACE United States Army Corps of Engineers USGS United States Geological Survey WSE Water Surface Elevation
- 2. PURPOSE
- a. Background In response to the nuclear fuel damage at the Fukushima Dai-ichi power plant due to the March 11, 2011 earthquake and subsequent tsunami, the United States Nuclear Regulatory Commission (NRC) established the Near Term Task Force (NTTF) to conduct a systematic review of NRC processes and regulations, and to make recommendations to the Commission for its policy direction. The NTTF reported a set of recommendations that were i1ntended to clarify and strengthen the regulatory framework for protection against natural phenomena.
On March 12, 2012, the NRC issued an information request pursuant to Title 10 of the Code of Federal Regulations, Section 50.54 (f) (10 CFR 50.54(f) or 50.54(f)) (Reference 2) which included six (6) enclosures:
- 1. [NTTF) Recommendation 2.1: Seismic
- 2. [NTTF) Recommendation 2.1: Flooding
- 3. [NTTF) Recommendation 2.3: Seismic
- 4. [NTTF) Recommendation 2.3: Flooding JOSEPH M. FARLEY NUCLEAR POWER PLANT Page 5 of 44 SNC PO No.: SNA31945-0002, Line 1, Item 764659 RCN: FAR0169.0
SAM NTTF Recommendation 2.1 (Hazard Reevaluations): Flooding October 20, 2015 Southern Nuclear Operating Company, Inc. Version 1.0
- 5. [NTTF] Recommendation 9.3: EP
- 6. licensees and Holders of Construction Permits In Enclosure 2 of Reference 2, the NRC requested that licensees 'reevaluate the flooding hazards at their sites against present-day regulatory guidance and methodologies being used for early site permits and combined license reviews.'
On behalf of Southern Nuclear Operating Company, Inc. (SNC), this report provides the information requested in the March 12, 50.54(f) letter; speclflcally, the information listed under the 'Requested Information' section of Enclosure 2, paragraph 1 ('a' through 'e') for the Joseph M. Farley Nuclear Power Plant (Plant Farley). The 'Requested Information' section of Enclosure 2, paragraph 2 ('a' through 'd'),
Integrated Assessment Report, will be addressed separately if the current design basis floods do not bound the reevaluated hazard for all flood causing mechanisms.
- b. Requested Actions Per Enclosure 2 of Reference 2, Addressees are requested to perform a reevaluation of all appropriate external flooding sources, including the effects from local intense precipitation (LIP) on the site, probable maximum flood (PMF) on st reams and rivers, storm surges, seiches, tsunami, and dam failures. It Is requested that the reevaluation apply present-day regulatory guidance and methodologies being used for ESP and calculation reviews including current techniques, software, and methods used in present-day standard engineering practice to develop the flood hazard. The requested information will be gathered in Phase 1 of the NRC staffs two phase process to implement Recommendation 2.1, and will be used to identify potential 'vulnerabilities' (see definition below).
For the sites where the reevaluated flood exceeds the design basis, addressees are requested to submit an interim action plan that documents actions planned or taken to address the reevaluated hazard with the hazard evaluation.
Subsequently, addressees should perform an integrated assessment of the plant to identify vulnerablllties and actions to address them. The scope of the Integrated assessment report will include full power operations and other plant configurations that could be susceptible due to the status of the flood protection features. The scope also includes those features of the ultimate heat sinks (UHS) that could be adversely affected by the flood conditions and lead to degradation of the flood protection (the loss of UHS from non-flood associated causes are not included). It is also requested that the integrated assessment address the entire duration of the flood conditions.
A definition of vulnerability in the context of [Enclosure 2] is as follows: Plant-specific vulnerabilities are those features Important to safety that when subject to an increased demand due to the newly calculated hazard evaluation have not been shown to be capable of performing their intended functions.
- c. Requested Information Per Enclosure 2 of Reference 2, the final report should be provided documenting results, as well as pertinent site information and detailed analysis, and include the following:
- a. Site information related to the flood hazard. Relevant structures, systems, and components (SSCs) important to safety and the UHS are included In the scope of this reevaluation, and pertinent data concerning these SSCs should be included. Other relevant site data includes the following:
JOSEPH M . FARLEY NUCLEAR POWER PLANT Page 6 of44 SNC PO No.: SNA31945-0002, Line 1, Item 764659 RCN: FAR0169.0
SAM NTTF Recommendation 2.1 (Hazard Reevaluations): Flooding October 20, 2015 Southern Nuclear Operating Company, Inc. Version 1.0
- i. Detailed site information (both designed and as-built), including present-day site layout, elevation of pertinent SSCs important to safety, site topography, as well as pertinent spatial and temporal data sets; ii. Current design basis flood elevations for all flood causing mechanisms; iii. Flood-related changes to the licensing basis and any flood protection changes (including mitigation) since license issuance; iv. Changes to the watershed and local area since license issuance;
- v. Current licensing basis flood protection and pertinent flood mitigation features at the site; vi. Additional site details, as necessary, to assess the flood hazard (i.e., bathymetry, walkdown results, etc.)
- b. Evaluation of the flood hazard for each flood causing mechanism, based on present-day methodologies and regulatory guidance. Provide an analysis of each flood causing mechanism that may impact the site including local Intense precipitation and site drainage, flooding in streams and rivers, dam breaches and failures, storm surge and seiche, tsunami, channel migration or diversion, and combined effects. Mechanisms that are not applicable at the site may be screened-out; however, a justification should be provided. Provide a basis for inputs and assumptions, methodologies and models used including input and output files, and other pertinent data.
- c. Comparison of current and reevaluated flood causing mechanisms at the site. Provide an assessment of the current design basis flood elevation to the reevaluated flood elevation for each flood causing mechanism. Include how the findings from Enclosure 2 of the S0.S4(f) letter (i.e.,
Recommendation 2.1 flood hazard reevaluations) support this determination. If the current design basis flood bounds the reevaluated hazard for all flood causing mechanisms, include how this finding was determined.
- d. Interim evaluation and actions taken or planned to address any higher flooding hazards relative to the design basis, prior to completion of the integrated assessment described below, if necessary.
- e. Additional actions beyond Requested Information item 1.d taken or planned to address flooding hazards, If any.
- 3. SITE INFORMATION
- a. Detailed Site Information Site Location The Joseph M. Farley Nuclear Plant (Plant Farley) is in Houston County, approximately 5 miles south of Columbia, Alabama. The site is located approximately 0.8 miles west of the Chattahoochee River and south of Wilson Creek. The site is across the Chattahoochee River from Early County, Georgia, approximately 120 miles southeast of Montgomery, Alabama and 90 miles northwest of Tallahassee, Florida. The site location is shown in Figure 3-1 (Reference llc).
Site Layout and Topography The Plant Farley site consists of approximately 460 acres. The powerblock area, which consists of the reactor and turbine buildings, is predominantly Impervious due to buildings, asphalt/concrete roads and walkways, and gravel areas in and around the powerblock area, switchyards, cooling tower area, JOSEPH M. FARLEY NUCLEAR POWER PLANT Page 7 of 44 SNC PO No,: SNA31945-0002, Line 1, Item 764659 RCN: FAR0169.0
SAM NTTF Recommendation 2.1 (Hazard Reevaluations): Flooding October 20, 2015 Southern Nuclear Operating Company, Inc. Version 1.0 simulator/training buildings, and warehouse area. The Service Water Intake Structure is located on the northeast edge of the service water pond and the south of the powerblock area (Reference 19).
The natural site and plant grade varies from approximately 210 ft NGVD29 to less than 120 ft NGVD29 at the Chattahoochee River. Overall, the site is elevated above Chattahoochee River and Wilson Creek with a north-south watershed divide through the switchyard west of the powerblock. The western and northern portion of the site drains north to Wilson Creek. The remainder of the site drains to the east and south eventually discharging into the Chattahoochee River. For the powerblock area, runoff from the switchyard drains east towards the turbine building, and then is routed by overland flow to the north or to the south by concrete channels and a series of culverts. The grade adjacent to the eastern side of the turbine and reactor buildings slopes easterly toward the Chattahoochee River (Reference 15).
The grade elevation at the control building, reactor building, and diesel building is 154.5 ft NGVD29 (Reference 7). The grade elevation at the Service Water Intake Structure is 195.0 ft NGVD29 (Reference 20). The site layout and topography is shown in Figure 3-2.
JOSEPH M . FARLEY NUCLEAR POWER PLANT Page 8 of 44 SNC PO No.: SNA31945-0002, Line 1, Item 764659 RCN: FAR0169.0
SAM NTTF Recommendation 2.1 (Hazard Reevaluations): Flooding October 20, 2015 Southern Nuclear Operating Company, Inc. Version 1.0
~
(ill IIW<tly HHC!land Q"i; (
~
othln A>hfonf
[I
' Site Drainage Boundary Evaluation or Plant Farttr Local fnttnH Prtclpltatlon -
Canonwood StY.,. Accident Manaa-ment {SAM) lo, Fuku1hlma Near-Tann T*k Force (NTTf)
RacommandaUon 2.1 Flooding R....,1fu1t1on Malone - "'"'
Flgutw S.1 r;-;"\
0 Figure 3-1: Site location of Plant Farley (USGS Quadrangle Reference llc)
JOSEPH M. FARLEY NUCLEAR POWER PLANT Page 9 of 44
$NC PO No.: SNA31945-0002, Line 1, Item 764659 RCN: FAR0169.0
SAM NTTF Recommendation 2.1 (Hazard Reevaluations): Flooding October 20, 2015 Southern Nuclear Operating Company, Inc. Version 1.0 Fleur* 3-2: Site layout and Topoaraphy of Plant Farlloy (Reference 19)
JOSEPH M. FARLEY NUCLEAR POWER PLANT Page 10 of 44 SNC PO No SNA31945-0002, Line 1, Item 764659 RCN FAR0169 0
SAM NTTF Recommendation 2.1 (Hazard Reevaluations): Flooding October 20, 2015 Southern Nuclear Operating Company, Inc. Version 1.0 Chattahoochee River Watershed The headwaters of the Chattahoochee River Basin begin in the mountain region of north Georgia, and then flows through the Piedmont Belt into the Coastal plain and on to the Gulf of Mexico. The Plant Farley site Is within the Coastal Plain where the river has a fairly uniform width and a gradual slope.
The dominant surface hydrological feature of the site's region is the Chattahoochee River. The drainage area of the Chattahoochee River watershed at Plant Farley Is approximately 8,215 square miles (Reference lla). The average flow in the Chattahoochee River at the site is approximately 11,500 cfs (Reference 7). A delineation of the Chattahoochee River watershed is provided i1n Figure 3-3 below.
N ame<!3 40 Miles A Figure 3-3: Chattahoochee River Watershed JOSEPH M. FARLEY NUCLEAR POWER PLANT Page 11 of44 SNC PO No.: SNA31945-0002, Line 1, Item 764659 RCN: FAR0169.0
SAM NTTF Recommendation 2.1 (Hazard Reevaluations): Flooding October 20, 2015 Southern Nuclear Operating Company, Inc. Version 1.0 Eleven (11) dams are on the main channel of the Chattahoochee River upstream of the site. Several of these are lower head dams that lack significant storage volume and do not contribute significantly to flow attenuation. Nine (9) dams/reservoirs located on the main channel of the Chattahoochee River upstream of the Plant Farley site are considered significant compared to the other dams on the Chattahoochee River main channel: Buford, Morgan Falls, West Point, Bartletts Ferry, Goat Rock, Oliver, North Highlands, George W. Andrews, and Walter F. George. These dams are active in controlling both daily flows for power generation and flood flows on, the Chattahoochee River. The FSAR (Reference 7) analyzed Buford, Morgan Falls, West Point, Bartletts Ferry, Goat Rock, Oliver, and Walter F. George Reservoirs. Table 3-1 below displays the major reservoir properties.
Table 3-1: Chattahoochee River Significant Reservoirs Storage Spillway Approximate Drainage Area Dam Capacity Crest (ft Miles Upstream (sq ml)
(acre-ft) NGVD29) from Farley Buford 2,554,000 \D}l.)) 10 1,036 300 USC§ Mor11an Falls 2,400 824o-1(d), 1,340 268 West Point 298,389 (b)(4) (b)(7) 3,437 150 Bartletts Ferirv 181,000 (F) 4,260 134 Goat Rock 8,500 4,535 128 Oliver 32,000 4,670 119 North Highlands 1,495 4,670 118 Walter F. George 690,000 7,463 30 George W. Andrews 9,980 8,197 2 The land use of the Chattahoochee River Watershed is predominantly rural with forested and agricultural lands with few large urbanized areas including Atlanta and Columbus, Georgia. A summary of the land cover of the watershed (Reference 11e) is provided in Table 3-2 below.
Table 3-2: Land Cover for the Chattahoochee River Watershed Land Cover Percentage Barren Land 0.3%
Cultivated Crops 3.5%
Deciduous Forest 28.9%
Developed, High Intensity 0.7%
Developed, Low Intensity 4.6%
Developed, Medium Intensity 1.4%
Developed, Open Space 7.8%
Emergent Herbaceous Wetlands 0.1%
Evergreen Forest 23.3%
Grassland/Herbaceous 4.9%
Mixed Forest 4.2%
Open Water 2.8%
Pasture/Hay 8.4%
Shrub/Scrub 5.6%
Woody Wetlands 3.5%
JOSEPH M. FARLEY NUCLEAR POWER PLANT Page 12 of44 SNC PO No.: SNA31945-0002, Line 1, Item 764659 RCN: FAR0169.0
SAM NTTF Recommendation 2.1 (Hazard Reevaluations): Floodlng October 20, 2015 Southern Nuclear Operating Company, Inc. Version 1.0 SSCs Important to Safety The following non-electrical SSCs are important to safety and aire located below site grade elevation for the Plant Farley power block which Is El. 154.5' (Reference 22):
- 1. Low Pressure/Decay Heat Removal pumps and valves (Residual Heat Removal System Ell): Pumps Ql/2E11P0001A/B are at floor elevation 77' -0" (References 23 and 24). The suction isolation valves Ql/2E11V0001A/B are located between 107' -1 "and 108'-6" (References 25, 26, 27 and 28). The discharge valves Ql/2E11V0002A/B are between elevations 81'-41/4" and 81'-41/2" (References 29, 30, 31 and 32).
- 2. High Pressure/makeup pumps and valves (Chemical and Volume Control System E21): Charging Pumps Ql/2E21P0002A/B/C are at Floor elevation 100'-0" (References 33 and 34). The RWST to Charging pump suction isolation valves Ql/2E21V0336A/B are at elevation 104'-9" (References 35 and 36). The Charging pump suction header isolation valves Ql/2E21V0324A/B and Ql/2E21V0325A/B are located at elevation 101'-6" (References 35 and 36). The charging pump discharge header isolation valves Ql/2E21V0326A/B and Ql/2E21V0327A/B are located at elevations 101'-6" and 109-6" (References 37, 38 and 39). The charging pump discharge check valves Ql/2E21V0122A/B/C are at elevation 107'-3" (References 35 and 36).
- 3. Emergency feedwater pumps and valves (Auxiliary Feed Water System N23): Pumps (Ql/2N23P0001A/18/2) are at Floor elevation 100'-0" (References 40 and 41). Suction check valves Ql/2N23V0006 and Ql/2N23V0007A/B are located between 111'-0" and 115'-0" (References 42 and 43). Pump discharge valves Ql/2N23HV3227A/B/C and Ql/2N23HV3228A/B/C are located at elevation 130'-0" (References 44 and 45).
The following Electrical SSCs are important to safety:
- 1. Emergency electrical power diesel generators (Floor El. 155'-0") (Reference 70)
- 2. Emergency electrical power distribution centers (lowest Plant Farley EL. 121'-0") (References 84 and 85)
- 3. Station batteries are at floor elevation 121'-0" (References 23 and 24)
- 4. Vital power inverters are at floor elevation 121' -0" (References 82 and 83)
- 5. Vital instrument power distribution centers are at floor elevations 139'-0"and 155'-0" (References 63 and 65)
- 6. Control room (Plant Farley control room is at elevation 155'-0" - (References 68 and 69)
Motor Control Center:
JOSEPH M. FARLEY NUCLEAR POWER PLANT Page 13 of 44 SNC PO No.: SNA31945-0002, Line 1, Item 764659 RCN: FAR0169.0
SAM NTTF Recommendation 2.1 (Hazard Reevaluations): Flooding October 20, 2015 Southern Nuclear Operating Company, Inc. Version 1.0
Station Batteries:
- 1. Q1R42E0002A-1A 125V Battery- Floor Elevation 121'*0" (Reference 60)
- 2. Q1R42E0002B -18 125V Battery- Floor Elevation 121'-0" (Reference 60)
- 3. Q2R42E0002A - 2A 125V Battery - Floor Elevation 121' -0" (Reference 58)
- 4. Q2R42E0002B - 2B 125V Battery- Floor Elevation 121'-0" (Reference 58)
Inverters:
- 1. Q1R21E0009A Inverter A - Floor Elevation 121'-0" ( Reference 62)
- 2. Q1R21E0009B Inverter B - Floor Elevation 121'-0" ( Reference 62)
- 3. Q1R21E0009C Inverter C- Floor Elevation 121'-0" ( Reference 62)
- 4. Q1R21E0009D Inverter D- Floor Elevation 121'-0" (Reference 62)
- 5. Q1R21E0009F-A- Inverter F - Floor Elevation 121'*0" (Reference 62)
- 6. Q1R21E0009G-B- Inverter G - Floor Elevation 121'-0" (Reference 62)
- 7. Q2R21E0009A Inverter A- Floor Elevation 121'-0" (Reference 58)
- 8. Q2R21E0009B Inverter B - Floor Elevation 121'-0" ( Reference 58)
- 9. Q2R21E0009C Inverter C - Floor Elevation 121'-0" (Reference 61)
- 10. Q2R21E0009D Inverter D - Floor Elevation 121'-0" (Reference 61)
- 11. Q2R21E0009F-A- Inverter F - Floor Elevation 121'-0" (Reference 58)
- 12. Q2R21E0009G-B - Inverter G - Floor Elevation 121'-0" (Reference 61)
Vital instrument power distribution centers:
- 1. Q1R21l0001A Vital AC Instrumentation Distribution Panel lA - Floor Elevation 155'-0" (Reference 63)
- 2. Q1R21L0001B Vital AC Instrumentation Distribution Panel 1B - Floor Elevation 155'-0" (Reference 63)
JOSEPH M. FARLEY NUCLEAR P*OWER PLANT Page 14 of 44 SNC PO No.: SNA31945-0002, Line 1, Item 764659 RCN: FAR0169.0
SAM NTTF Recommendation 2.1 (Hazard Reevaluations): Flooding October 20, 201S Southern Nuclear Operating Company, Inc. Version 1.0
- 3. QlR21L0001C Vital AC Instrumentation Distribution Panel lC - Floor Elevation 139'-0" (Reference 63)
- 4. Q1R21L00010 Vital AC Instrumentation Distribution Panel 1D - Floor Elevation 139'-0" (Reference 63)
- 5. Q2R21L0001A Vital AC Instrumentation Distribution Panel 2A - Floor Elevation 155'-0" (References 64 and 65)
- 6. Q2R21L0001B Vital AC Instrumentation Distribution Panel 2B - Floor Elevation 155'-0" (References 64 and 65)
- 7. Q2R21L0001C Vital AC Instrumentation Distribution Panel 2C - Floor Elevation 139'-0" (Reference 64)
- 8. Q2R21L00010 Vital AC Instrumentation Distribution Panel 20 - Floor Elevation 139'-0" (Reference 64)
Emergency electrical power distribution centers (The Emergency buses at Plant Farley are F, G, H, J, K and L):
- 1. Q1R15A006A- Switchgear Bus F - Floor elevation 139'-0" (Reference 47)
- 2. Q2Rl5A006A- Switchgear Bus F - Floor elevation 139'-0" (Reference 48)
- 3. Q1Rl5A007B - Switchgear Bus G - Floor elevation 121'-0" (Reference 49)
- 4. Q2R15A007B - Switchgear Bus G - Floor elevation 121' -0" (Reference SO)
- 5. Q1Rl5A503A - Switchgear Bus H - Floor Elevation 151' -0" (Reference 51)
- 6. Q2R15A503A - Switchgear Bus H - Floor Elevation 151' -0" (Reference 51)
- 7. Q1Rl5A504B - Switchgear Bus J - Floor Elevation 151'-0" (Reference 51)
- 8. Q2R15A504B- Switchgear Bus J - Floor Elevation 151'-0" (Reference 51)
- 9. Q1R15A505A - Switchgear Bus K - Floor Elevation 198'-9" (Reference 52)
- 10. Q2R15A505A -Switchgear Bus K - Floor Elevation 198'-9" (Reference 52)
- 11. Q1R15A506B-Switchgear Bus L -Floor Elevation 198'-9" (Reference 53)
- 12. Q2R15A506B-Switchgear Bus L - Floor Elevation 198'-9" (Reference 53)
- b. Current Design Basis Flood Elevations for All Flood Causing Mechanisms The design basis was reviewed to determine which flood-causing mechanisms are considered in the current design basis flood. Below is a summary of flood-causing mechanisms considered and not considered in the design basis.
- 1. Local Intense Precipitation Per the FSAR, the PMP was not used as the basis for design of Category I structures because the supporting analysis did not show ponding in the power block area. Based on the analysis, the topography of the plant is directed runoff from rainfall away from the power block area, both by natural drainage and by a combined system of culverts along with open ditches to the natural drainage channels. These channels subsequently JOSEPH M. FARLEY NUCLEAR POWER PLANT Page 15 of44 SNC PO No.: SNA31945-0002, Line 1, Item 764659 RCN: FAR0169.0
SAM NTTF Recommendation 2.1 (Hazard Reevaluations): Flooding October 20, 2015 Southern Nuclear Operating Company, Inc. Version 1.0 outlet to the Chattahoochee River. Therefore, the topography for the power block area precludes flooding safety-related structures from the PMP (Reference 7).
The PMP for the power block area was selected from the World Record Envelop Curve as shown on Figure 9-44 in Chow's Handbook (Reference 7).
Rainfall in.= 15.3 x (duration in hours) 0 *486 The runoff from local PMP across the plant area was checked using the rational method. The underground storm drainage system was assumed inoperative allowing only overland flow routing for PMP runoff. The depth of water at check locations was determined by using the Manning equation. The maximum water depth adjacent to the turbine building was 6 inches, which is 6 i nches below slab grade (Reference 7).
A second PMP was estimated for the storage pond used as the ultimate heat sink. The crest length of the storage pond dam and dike ls 3,900 ft with the crest at elevation 195 ft NGVD29. The drainage basin that feeds the storage pond is apprnximately 325 acres. The design storm for this basin was assumed to be a 6-hour storm with a PMP of 29.9 inches. The PMP will raise the storage pond to elevation 192.2 ft NGVD29 and with maximum wave runup reaching elevation 194.0 ft NGVD29 (Reference 7).
- 2. Flooding In Streams and Rivers The PMF was used as the basis for hydrologic design of Category I structures in the power block area. The maximum flood elevation for the Chattahoochee River at the site of 144.2 ft NGVD29 is based upon a PMF discharge of 642,000 cfs (Reference 7).
The primary consideration in determining the flood potential was the probable maximum depth of precipitation occurring over the drainage basin above the plant site. The basic method described in U.S.
Weather Bureau Hydrometeorological Report No. 33 was used for this analysis. To estimate t he PMP for the 8,246 square mile Chattahoochee River Basin, the large storm of March 11 to 16, 1929 (LMV 2-20 -Elba, Alabama) was transposed over the Chattahoochee River basin upstream of the site. The storm with the primary center located at 84-S1-l0W, 32-20-20N, with the isohyetal pattern rotated 20 degrees counter clockwise from its original bearing, would produce the maximum volume of precipitation in the drainage basin above the site. The average total depth of storm rainfall across the river basin was 15.7 inches. The average depth of rainfall excess over the drainage basin was 12 .9 inches (Reference 7).
The ground was assumed to be saturated at the start of the storm, so no initial infiltration loss was considered. An average storm infiltration rate of 0.05 in/hour was used for the study (Reference 7).
A rainfall runoff model was developed to estimate a PMF peak discharge at Plant Farley. The drainage basin above Columbia lock and Dam was subdivided into 16 areas. A 6-hour unit hydrograph was developed for each of these areas by the Corps of Engineers from various storm and flood records. The 6-hour increments of rainfall excess for each of the 16 areas were routed down the river by the progressive average lag method and, through the Corps of Engineers' reservoirs. Reservoir operations, spillway rating curve and capacity curves were obtained for select upstream in-line reservoirs on the Chattahoochee River. The resulting PMF peak discharge at the site was 642,000 cfs (Reference 7).
A stage-discharge relationship was developed for the Plant Farley site at Chattahoochee River mile 44.3 using the USACE HEC-2 Water Surface Profiles program. Eighty-five river valley cross-sections were obtained from USACE contour maps extending from river mile 10.54 to 75.1. The model was calibrated using known high water marks from two historical floods occurring in March 1929 and February 1961. The resulting PMF peak river stage was 144.2 ft NGVD29 (Reference 7).
JOSEPH M. FARLEY NUCLEAR POWER PLANT Page 16 of 44 SNC PO No.: SNA31945-0002, Line 1, Item 764659 RCN: FAR0169.0
SAM NTTF Recommendation 2.1 (Hazard Reevaluations): Flooding October 20, 2015 Southern Nuclear Operating Company, Inc. Version 1.0
- 3. Dam Breaches and Failures Hydrologic Failure The major dams above the site that could affect the maximum water level at Plant Farley have been designed by the Corps of Engineers. These dams are designed to withstand the PMF flow and were not considered as failing under this condition. Of the other dams that might affect the conditions at Plant Farley, Bartletts Ferry Dam was the primary dam considered as part of the current licensing basis. Bartletts Ferry, as it existed at the time of the current licensing basis analysis, could not contain its spillway to provide more capacity (Reference 7).
During failure, Bartletts Ferry reservoir was assumed to draw down from elevation 530 ft to elevation 450 ft, releasing about 215,000 acre-ft of water. Assu~
- this complete failure occurred during the passing of f~~I~-~~j~~ - thePMFforPlantFarleybyBartlettsferryOam;a surge wave would result below the dam. B domino
"' ,~,rn,n type failure, Goat Rock and Oliver dams would fal resulting in afl tt surge..wave at \~~\3\~~4~ ~b~l~~24o- Dam,(?)(3) 1? U S C.
89 miles below Oliver Dam, which would reflect from the dam. -Im decay of amplitl'rm"Tl'l-.:-rnrrnr'"Olr.lrm:i'<; wa~.~2,~?~,\~, (b) derived from discussions given on solitary wave decrease with distance In Engineering Hydraulics by Hunter Rouse, page 724, and a com uter ro ram for unsteady nonuniform f low developed by J. J. Stoker.
3 1 Assuming the sur reached :;( ~ ~ c : 4o- Dam at the same t ime as the peak PMF flow is passing, it 82 1 (b)(3) 16 USC
~}2 ,~?~:(~i(b) .
8 w.a.uld...add about ***** ft to th se oir eve and cause an additional 88,000 cfs discharge through the spillway. Assuming this additional flow continues to Plant Farley, this would raise the peak flooding discharge! (PMFI plus Bartletts Ferry dam break) to 730,000 cfs and the Chattahoochee River peak stage to (b)(3) 16 U S.C ........elevation ........... ft NGVD29 at the site (Reference 7).
§ 824o-1(dr(bj IA\ IL\1"7\lr\ se*s *c ai u (b)(3)16USC (bJ(3J16USC§824:,. []
§ 824o-1(d},(b) ******** 1fd: {blt4l.lb)fl}(F\ Dam and **************** Dam were both considered to be breached by seismic failure (Reference IA\ IL\1-,\lr""\
! 1-3 1 (b)( ~U ~- ~ ailure ere _ domino-type failure effect from wave action ultimately resulting M~!~~t~ .. ~ e wave at \~~t\~~~ ~b~7JM 4o- 2 Dam, which would reflect and be contained within t he reservoir (4) (b)(7)(F) (Reference 7).
~b~~!:~~(~r~(~
"' ,L,,.,,,,_;
l 357,000 of loam was considered to be breached during the crest of a standard project flood discharge cfs w,l h the reservoir at elevation 201 ft NGVD29 and the tallwater at elevation 16 NGVD29, by a seismic event. Breaching t Jconservatively assumed to be the ibX3l 16 u 8 c § 824o-1(dl (bl(4) (b)(7) ft earth
~b~~i~~~?i~
,., ,um,.--
. ..dike....section over a period o ******* minutes (selected to facilitate computer analysis). This gave the most critical condition that was con ed reasonable to possibly occur (Reference 7).
(b}(3) 16 U SC § 824o-1 An unsteady flow analysis of the (dJ. (b)(4). (b)(?J(F) Dam seismic failure was performed using a computer program f~ eady nonuniform ow eve ope y J. J. Stoker. The resulting peak river stage at Plant
~b~~!~~~)~(~ Farleywast:_Jft NGVD29 (Reference 7).
- 4. On-site Storage Pond Dike Failure Flooding of the plant power block area due to flow from the storage pond is addressed in FSAR Section 2.4.10. The storage pond dam and dike are designed to withstand (a) the safe shutdown earthquake (SSE) and (b) the storage pond PMP with coincident high winds. Nonetheless, failure of the storage pond dike was assumed in order to assess potential consequences. The storage pond dike is located so that the resulting discharge of water would not be directed into the plant area (Reference 7).
JOSEPH M. FARLEY NUCLEAR POWER PLANT Page 17 of44 SNC PO No.: SNA31945-0002, Line 1, Item 764659 RCN: FAR01 69.0
SAM NTTF Recommendation 2.1 (Hazard Reevaluations): Flooding October 20, 2015 Southern Nuclear Operating Company, Inc. Version 1.0
- 5. Probable Maximum Surge, Selche, and Tsunami Flooding The Plant Farley site is not near a large body of water, thus flooding induced by surge, seiche, or tsunami does not apply (Reference 7).
- 6. Ice Flooding Icing does not normally occur on the Chattahoochee River at Plant Farley. No record of the river being iced over at this location has been found. Therefore, there would be no interference with the flow of water into the river water intake due to ice. Even If the surface did become frozen there would be no Interference with withdrawal of water by the river water intake due to depth of water in the river (Reference 7).
- 7. Channel Migration or Diversion The river upstream from the site does not have sufficiently high banks to cause a potential diversion of the river and bypass of the intake structure. With Lake Seminole varying between elevation 76 ft NGVD29 and elevation 78 ft NGVD29, a tennporary blockage of the river upstream from Plant Farley would not seriously affect the quantity of water available to the river water intake structure. Even if the river was temporarily blocked, cooling water could be obtained from the storage pond (Reference 7).
- 8. Combined Effects Flooding PMF and Wave Runup The CLB postulates a 50 mph wind occurring concurrently as the PMF peak flood stage of the Chattahoochee River (144.2 ft NGVD29). The wave runup analysis was based on procedures provided in "Freeboard Allowances for Wave in Inland Reservoirs" by Saville, Mcclendon and Cochran. The wave study indicated that the runup of the significant wave would be 9.1 ft or at elevation 153.3 ft NGVO29. It was concluded that the wave water will not reach the main plant area (Reference 7).
Hydrologic Failure and Wave Runup If a surge due to the failure of Bartletts Ferry,llfm reached Walter F. George Dam at the same time as the (b)(3) 16 USC.
peakPMFJlowispassing;itwouldaddabout_jft to the reservoir level and cause an additional 88,000 cfs
§ 824o-1(d}:(b) .
discharge through the spillway~ ing this additional flow continues to Plant Farley, this would raise the
.Jhte.rine. flooding elevationto*t:_J ft NGVD29. lf a coincidental sustained wind velocity of 40 mph is considered occurrM ring this peak flow, it could cause a runup of the significant wave of 7.2 ft on 3:1
- ~~::~~~~~e~:~~oyo~ :~~Gi~~~gb:~!~~~ eh~~h~~~:a;1etl~;:~i~~l nt*~*-* (*ta~GPV~;,9d~~w~~~~!h!~~-~ri-~~~~;~,(~~(~
mph wind) to occur simultaneously at Plant Farley. This type of failure was considered so improbable that it was not further considered to endanger the plant (Reference 7).
Seismic Failure and Wave Run up A wind velocity of 50 mph is considered for the seismically induced dam failure combined with wav~ .
(b)(3) 16 U SC .
!P~2J.dff~)S(ll)
The wave ~!,!Il.\,m .oL9.lftonari~ ageofE : ) ft NGVD29 would reach an elevation ofL : :t t -~JP:6,~)s(~
NGVD29.ThisJsJessthanelevationt=__f NGVD for the PMF and Wave Runup (Reference 7). ,., ,L~m,r:
§' BZ46-'11UJ'. (b)
- c. Flood Related Changes to the Licensing Basis and Any Flood Protection Changes (including mitigation) Since License Issuance Flood-Related Changes to the Licensing Basis since License Issuance The following is a summary of flood-related changes to the licensing basis since license issuance:
- There have been no changes to the CLB since last issuance.
JOSEPH M . FARLEY NUCLEAR POWER PLANT Page 18 of 44 SNC PO No.: SNA31945-0002, Line 1, Item 764659 RCN: FAR0169.0
SAM NTTF Recommendation 2.1 (Hazard Reevaluations): Flooding October 20, 201S Southern Nuclear Operating Company, Inc. Version 1.0 Flood Protection Changes Since License Issuance The following is a summary of flood protection changes since license issuance:
- The Service Water Culvert was identified as a deficiency due to partial blockage during the Flood Walkdown (NEI 12-07) on September 21, 2012 and promptly corrected (reference CR 521936 and CR 521939). (Reference 13)
- The flood walkdown process verified the Farley Units 1 & 2 flood protection CLB and determined that no additional or enhanced flood protection features were necessary. (Reference 12)
- d. Changes to Watershed and Local Area since License Issuance The following is a summary of changes to the watershed and local area since license issuance:
- At the time of the CLB analysis, a new spillway was being added at Bartletts Ferry reservoir to Increase spillway capa,city. That new spillway capacity was not considered in the CLB. The FSAR states that the spillway construction was to be completed in 1985 (Reference 7).
- e. Current Licensing Basis Flood Protection and Pertinent Flood Mitigation Features The topography of the Plant Farley Is such that none of the safety-related facilities are exposed to river flooding by the most severe flood t : tite. The PMF elevation including dam break and the maximum (b)(3) 16 U S C.
w.ave....runup,....would..be at elevation ************** ft NGVD29. This is below the plant grade at elevation 154.5 ft
§ 824o-f{d}:' (b)'"
NGVD29 and, therefore, flooding of e power block area is improbable from this source. (Reference 12)
There are no safety-related systems or components located below the design maximum flood elevation that are not protected against flooding. The foundation slabs and exterior walls of safety-related structures are designed to resist upward and lateral pressures caused by the maximum flood level. (Reference 12)
The plant underground drainage system is designed for a maximum precipitation of 6 inches per hour. With the underground drainage system blocked, the ground surface topography and combination of ditches and natural drainages ensures that flooding of safety-related equipment does not occur as a result of local intense precipitation equal to the PMP. (Reference 12)
Chattahoochee River Flood Duration The PMF flood at the plant site begins approximately 12 days following the start of the design PMP event.
The river returns to normal elevation approximately 10 days after beginning of the PMF flood. (Reference 7)
Credited CLB Flood Protection Features Structures, systems, and components (i.e., features) relied upon for protection against external floods are designated as "flood protection features" and can be either passive or active. For Plant Farley Units 1 & 2, credited flood protection features are passive and include those credited for mitigating floods from surface and subsurface sources. Farley's credited flood protection features are independent of operating mode and, therefore, changes in operational mode do not.affect the flood protection features' ability to protect safety-related SSCs. (Reference 12)
SSCs (i.e., features) relied upon for protection against external PMP, PMF or groundwater floods are designated as "flood protection features" and can be either passive or active. For Plant Farley l!Jnits 1 & 2, credited flood protection features are passive. (Reference 12)
The features assessed during plant walkdowns are organized into the following categories (Reference 12):
- Topography JOSEPH M. FARLEY NUCLEAR POWER PLANT Page 19 of44 SNC PO No.: SNA31945-0002, Line 1, Item 764659 RCN: FAR0169.0
SAM NTTF Recommendation 2.1 (Hazard Reevaluations): Flooding October 20, 2015 Southern Nuclear Operating Company, Inc. Version 1.0
- Exterior walls, including penetration seals and waterstops
- Piping and electrical tunnels
- Storage Pond ,(UHS) dike None of the safety-related facilities in the power block area are susceptible to surface flooding by the PMF, (b)(3) 16 U SC
§ 824o-1(dr(b) whos~ _highest. elevationJs atEJft NGVD29 (FSAR Section 2.4.3), or to subsurface flooding from groundwater. (Reference 12)
The power block is also protected from floods caused by an assumed failure of the Seismic Category I UHS cooling water storage pond. In this case, water is diverted from the power block by the configuration of the dam and dike relative to natural drainage features, and the topography between the storage pond and the power block. (Reference 12)
Active flood Protection Features for external floods, Farley Units 1 & 2 do not rely upon active flood protection features such as sump pumps, portable pumps, isolation and check valves, flood detection (e.g., level switches), or watertight doors. (Reference 12)
Temporary Flood Protection Features for external floods, Farley Units 1 & 2 does not rely upon temporary features for protection. (Reference 12)
Operator Actions I Applicable Procedures I Guidance The Farley Nuclear Plant Abnormal Operating Procedure for Severe Weather, FNP-0-AOP-21.0 (Reference 75), provides actions in response to severe weather conditions. This procedure is entered when severe weather conditions are experienced or anticipated from any of the following (Reference 12):
- River level approaching 95 ft and continued rise is projected.
- Report of a tornado or tornado warning.
- Sustained winds in excess of 35 mph, from a, named storm system, are forecast for the plant site within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> by the National Weather Service or by an appropriate weather service approved by SNC management.
- Heavy or excessive rainfall greater than 6 inches per hour.
- Extended (>7 days) heat wave with daily ambient temperatures exceeding 95 degrees F.
- Management discretion when deemed appropriate.
- f. Additional Site Details The Flood Walkdown inspection (NEI 12-07) (Reference 12) completed in November 2012 identified 32 degraded conditions with respect to flood protection and APM features. A total of 20 condition reports were written against flood protection features and 12 were written against APM features. Degraded conditions identified during the flood walkdowns were evaluated in accordance with station processes and entered into the CAP. In all cases, the degraded flood protection features were determined to be capable of performing their intended flood protection function when subject to a design basis flooding hazard and therefore are not reportable to the NRC. (Reference 12)
During an assessment of all condition reports, the following conditions were determined to have similar characteristics (Reference 12).
JOSEPH M. FARLEY NUCLEAR POWER PLANT Page 20 of44 SNC PO No.: SNA31945-0002, Line 1, Item 764659 RCN: FAR0169.0
SAM NTTF Recommendation 2.1 (Hazard Reevaluations): Flooding October 20, 2015 Southern Nuclear Operating Company, Inc. Version 1.0
- Exterior Door Seals and Thresholds -CRs were generated which identified deteriorated door seals and threshold that need to be addressed. Reference CRs 519139, 519141, 519833,519835,520587,520589, 520590, 521235,521272,521942.
- Minor Cracks in Concrete Walls
- CRs were generated which identified these minor cracks Reference CRs 519150, 519153, 519825, 519826, 519828, 521269, 521278.
- Piping and Electrical Seals - CRs were generated which identified various types of electrical and piping seals that need to be addressed. Reference CRs 519821, 519822, 520603, 521275, 522069.
- Stains on Walls - CRs were generated which identified staining on wall that need to be addressed.
Reference CRs 520595, 520601, 520604, 520611, 521276, 521277, 521279.
The Service Water Culvert was identified as a deficiency due to partial blockage during the Flood Walkdown (NEI 12-07) on September 21, 2012 and promptly corrected (reference CR number 521936) (Reference 13).
- 4.
SUMMARY
OF FLOOD HAZARD REEVALUATION The following ls a summary evaluation of the flood hazard at Plant Farley for each flood causing mechanism described in NUREG/CR-7046. These evaluations are based on acceptable industry standard methodologies and regulatory guidance. An analysis to identify each flood causing mechanism that may impact the site was performed including local intense precipitation and site drainage, flooding in streams and rivers, dam breaches and failures, channel migration or diversion, and combined effects. Mechanisms that are not applicable at the site (i.e., storm surge, seiche, and tsunami) have been screened-out as described below.
- a. Local Intense Precipitation The LIP is a measure of the extreme precipitation (high intensity/short duration) at a given location. The duration of the event and the support area are needed to qualify an extreme precipitation event fully.
Generally, the amount of extreme precipitation decreases with increasing duration and increasing area.
2 NUREG/CR-7046 (Reference 4) specifies that the LIP should be equivalent to the 1-hr, 2.56-km (1-mi2) probable maximum precipitation (PMP) at the location of the site.
The LIP event was evaluated for Plant Farley to determine the associated flooding elevation and velocities assuming the active and passive drainage features are non-functioning. The LIP evaluation was performed in accordance with the NRC's "Design-Basis Flood Estimation for Site Characterization at Nuclear Power Plants in the United States of America," dated November 2011 (NUREG/CR-7046). The LIP evaluation was developed in Calculation Package SC-SNC453276-004 (Reference 18).
The model was created with boundaries that encompass the local site drainage. Plant Farley is elevated from its surrounding topography and runoff drains to Wilson Creek in the north, a small tributary of Wilson Creek that also drains the Cooling Pond to the west, and the Chattahoochee River floodplain to the south and east.
The runoff caused by the LIP event was estimated using the FL0-2D software (Reference 8). The software uses shallow water equations to route stormwater throughout the site. The methodology used w ithin the FL0-20 software includes the rainfall function; area and width reduction factors to account for ISFSI Storage Pads; and the levee function to reflect the site security features, which could potentially impact the natural drainage characteristics of the site.
The FL0-20 model was constructed from a Digital Elevation Model (DEM). The DEM was developed using LiDAR (Light Detection and Ranging) data (Reference 15) and supplemented with as-built drawings of site JOSEPH M. FARLEY NUCLEAR POWER PLANT Page 21 of44 SNC PO No.: SNA31945-0002, Line 1, Item 764659 RCN: FAR0169.0
SAM NTTF Recommendation 2.1 (Hazard Reevaluations): Flooding October 20, 2015 Southern Nuclear Operating Company, Inc. Version 1.0 features (e.g., drainage features such as side ditches). Exterior door elevations and the surrounding areas of the safety related structures were surveyed by SNC and reported in Calculation Package SC-SNC453276-007 (Reference 9). These points were also included in the DEM.
The levee feature was used to represent the Kontek Vehicle Barriers in the FL0-20 model to account for the vehicle barrier's effects on local drainage patterns. Openings (roads, etc.) in the vehicle barriers were modeled in FL0-20 accordingly. Gaps between the individual blocks of the vehicle barriers were not modeled in FL0-20 because they were considered minimal/non-existent during the site reconnaissance.
Also, flow patterns at the site are predominantly away from the safety-related structures due to site topography/grading and, therefore, not showing minor gaps between the individual blocks is considered a conservative approach.
To represent obstructions in the model, the buildings, tanks and cooling towers were coded into the FL0-20 grid surface using approximate top/ roof elevations based on the raw liDAR data (Reference 18). Buildings were modeled as grid elements with higher elevation. There was no credit taken for any roof parapets on Reactor/Turbine Buildings and roof drains were assumed to be blocked.
The FL0-20 model uses Manning's Roughness Coefficients (n-values) to characterize the site's surface roughness and calculate effects on flow depths and velocities. Manning's n values were obtained from the FL0-20 Reference Manual, Version 2009 (Reference 10). land cover for the site was evaluated using interpretation of orthoimagery that was verified in the field by AMEC.
The 1-hour PMP event distribution was developed using Hydrometeorological Report 52 (HMR 52)
(Reference 14). Per NUREG/CR-7046, the LIP event is defined as a 1-hour/1-square-mile PMP event. The total PMP depth per square mile for the 1-hr event was extrapolated from the PMP depth contour map provided in Figure 24 of HMR 52 (Reference 14). The distribution of the 1-hr PMP was developed for the 5-,
15-, and 30-minute time intervals, with the 60-minute interval being the 1-hour PMP depth. The 1-hour PMP distribution is provided in Table 4-1 and Figure 4-1 below.
Since the 1-hour/1-square-mile PMP event would fully encompass the contributing drainage area of Plant Farley, the evaluation of a longer duration and larger storm event (6-hour/10-square-mile) was not warranted. This approach Is in accordance with the definition of the LIP event per NUREG/CR-7046 (Reference 4). In addition, because of the rainfall intensity during the first hour of the storm event, the amount of precipitable water available for a longer duration storm event would be minimal compared to the first hour. Therefore, any increase in maximum flood levels due to a longer duration storm event is unlikely.
The 1-hr PMP event temporal distribution was developed in ac,cordance with HMR 52, which provides a set of multiplication factors for the 5-, 15-, and 30-minute t ime intervals relative to the 1-hr, 1-mi2 PMP depths.
While HMR 52 does not specifically state the time intervals be arranged In this particular order, with the typical west-east flow across North America, the type of storm set-up that would provide an LIP would likely be a mesoscale convective system. Typically in this type of weather system the initial precipitation is associated with the mature cells and a zone of convergence and as such will be very intense. The storm motion and nature of the system would then see a decrease In the precipitation after the initial burst as the rear trailing stratiform region with the cold pool moves over the area. This type of meteorological system fits with the front loaded distribution (Reference 86).
JOSEPH M. FARLEY NUCLEAR POWER PLANT Page 22 of44 SNC PO No.: SNA31945-0002, Line 1, Item 764659 RCN: FAR0169.0
SAM NTTF Recommendation 2.1 (Hazard Reevaluations): Flooding October 20, 2015 Southern Nuclear Operating Company, Inc. Version 1.0 Table 4-1: 1-hr/1-sq-ml PMP Distribution for Plant Farley Time Percent Total PMP Cumulative Depth Reference (minutes) (%) (Inches) 0 0% 0.00 N/A 5 32.00% 6.19 Figure 36 of the HMR-52 manual 15 50.08% 9.68 Figure 37 of the HMR-52 manual 30 73.22% 14.15 Figure 38 of the HMR-52 manual 60 100% 12.,ll . Figure 24 of the HMR-52 manual 20 J
18 1-- 1-1--
vi a.,
16
.5 14
-50.
0 a.,
12 10 -
~
ii
~ 8
~
J!C 6
'iii a:: 4 . ,- , -, -
2 1--
0 L, 0 10 20 30 40 50 60 Time (minutes)
Figure 4-1: 1-hr PMP Distribution for Plant Farley The flooding elevations associated with the LIP were calculated by applying the 1-hour/1-square-mile storm evenly across the site in the FL0-2D model. The model was run for 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> to allow for the site to drain and with only the areas of static ponding remaining at the end of the model run.
Per recommendations provided by NUREG/CR-7046, runoff losses were ignored during the local intense precipitation event in order to maximize the runoff from the event. Only overland flow and open channel systems were considered in the LIP flooding analysis (Reference 4).
All active and passive drainage system components (e.g., pumps, gravity storm drain systems, small culverts, inlets, etc.) were assumed non-functional or clogged during the LIP event, per Case 3 in NUREG/CR-7046 (Reference 4).
The LIP evaluation was conducted independently of external high-water events. That is, the LIP event was assumed to have occurred non-coincident to a river flood. Therefore, backwater or tailwater was not considered. NUREG/CR-7046 dloes not specify that an external condition be considered for LIP flood hazard evaluations (Reference 4).
JOSEPH M. FARLEY NUCLEAR POWER PLANT Page 23 of 44 SNC PO No.: SNA31945-0002, Line 1, Item 764659 RCN: FAR0169.0
SAM NTTF Recommendation 2.1 (Hazard Reevaluations): Flooding October 20, 2015 Southern Nuclear Operating Company, Inc. Version 1.0 The LIP flooding evaluation (per Case 3 assumptions of NUREG/CR-7046, Section 3.2) calculated the maximum flooding depths, water surface elevations, velocities, resultant static loads, and resultant impact loads that could be expected during the LIP event, assuming the surface drainage system and storm sewer system are fully blocked. The maximum predicted water surface elevation and resulting depth can be seen below in Table 4-2.
JOSEPH M. FARLEY NUCLEAR POWER PLANT Page 24of44 SNC PO No.: SNA31945-0002. Line 1, Item 764659 RCN: FAR0169.0
SAM NTTF Recommendation 2.1 (Hazard Reevaluations): Flooding October 20, 2015 Southern Nuclear Operating Company, Inc. Version 1.0 Table 4*2: LIP Prodlcted Floodl111 R1,ults at the Main Doors and Bays Max.
ftefet1nce M*x. ffoodln1 Floodlns Mu.
5'1,.,..,.d Rn/shed Floor Max. Wat-er Surface Maw. AHUttant Grid O.plh 1bov1 Duration Resultant DoorlD lulldins Elevation (FFE) flevallon Velochy lmpect Eltmnt FFE 1bgy1 FFE Static Load I.Nd No.
It (NAVDa) lt(NGVD29) lt(NAVDII) lt(NGVD29) It hr ft/soc lb/It lb/ft Ooor40S 68240 154.S3 154.86 154.99 lSS.32 0.46 1.30 0.59 0.18 6.51 Door441 67604 154.48 154.81 154.87 155.20 0.39 I .JO 0.23 0.03 us Door442 58948 154.68 155.01 154.97 155.30 0.29 1.00 0.7S 0.62 8.41 Auxrtia,y Unit Na, t Door443 51563 154,73 155.06 154.98 155.ll 0.25 1.00 0,66 0,41 5.34 Door436 57800 154.67 155.00 155.39 155.72 0.72 I.JO 0.73 1.78 57.87 PA109 57034 154.67 155.00 155,42 155.75 0.75 I .JO 1.07 3.34 SI.IS Door2405 68248 154.52 154.BS 154,94 155.27 0.42 1.10 0.68 0.23 5.44 Door 2441 67644 154,44 154.n 154,69 155.02 0.25 0 .60 0.30 0.04 2.02 Door 2436 51211 154.70 155.03 155,37 155.70 0.67 1.60 0.50 0.39 13.88 Au!dliary Unit No. 2 Door 2442 58603 154.68 155.01 154.79 155.12 0.10 0.30 0.42 0.05 0.41 Door 2443 59374 154,73 155.06 154.87 155.20 0.14 0.10 0.4-4 0.05 0.62 PA121 57048 154,67 155.00 ISS.48 155.81 0.81 Max' 0.78 0.31 31.13 Door468 Conulnment Untt No. 1 65121 154.15 154.48 154.90 155.23 0.75 1.30 0.71 0.70 17.40 Door 2468 Containment Unil No. 2 65167 154.17 154.SO 154.66 !S4,99 0.49 1.30 0.48 0.21 7.48
[).854 111063 19S.18 195.51 195.Sl 195.84 0.33 1.00 0.4-4 0.09 3.49
[).855 service Water Intake Structurt 112076 195.28 195.61 195.48 195.81 0.20 0 .30 0.35 0.03 1.26 1
T856 110965 194.64 194.97 195.Sl 195.84 0.87 Mn 0.37 0.22 23-76 JOSEPH M. FARLEY NUCLEAR POWER PLANT Page 25 of 44 SNC PO No SNA31945-0002, lino 1, Item 784659 RCN FAR0169 O
SAM NTTF Recommendation 2.1 (Hazard Reevaluations): Flooding October 20, 2015 Southern Nuclear Operating Company, Inc. Version 1.0 Mix.
Reference Mu. f loodln1 Floodlnl Mu.
SUMlyed finished floo, Mu. Wattr Surlac:1 Max, Resultant G~d D1pth1b..1 Duration Rtsuttant DoorlO lulldlna ElenUon lfFE) U1¥1tlon Volodty Impact Element FFE above ff£ Stade toad toad No.
IIINAVOII) ll(NGV029) ll(NAVDII) ftlNGVD29) ft hr ft/H< lb/II lb/II D-720 67891 154.81 IS5.14 154.9S 155.28 o.u 0.20 053 007 065 0 -721 616Z7 154.80 155.13 1S4.94 155.27 0.14 0.10 0.90 0.24 0,60 D-723 65111 154.6S 154.98 mos 155,41 0.43 Max1 056 0 20 207 D-724 Olesel Generator 654Zl 1S4.89 155.22 155.11 ISS.44 0.22 1.00 062 0.21 LS3 0-735 67892 153.72 1S4.05 154,77 155.10 1.05 Mn1 037 0 36 34.16 D-736 61627 152.53 152.86 154.94 1S5.27 2.41 Max1 0,90 0.24 0,60 1
D-737
. . 65422 154.65 The model was slmul11ed for 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />. Mu mtaru full model Jfmulation time, 154,98 IS4.98 1S5.31 0,33 1.00 072 0 ,39 3.40 JOSEPH M. FARLEY NUCLEAR POWER PLANT Page 26 of 44 SNC PO No SNA3194S-0002, Line 1, llem 764659 RCN FAR0169 0
SAM NTTF Recommendation 2.1 (Hazard Reevaluations): Flooding October 20, 2015 Southern Nuclear Operating Company, Inc. Version 1.0
- b. Flooding in Streams and Rivers The PMF in rivers and streams, adjoining the site should be determined by applying the PMP to the drainage basin in which the site is located. The PMF Is based on a transformation of PMP rainfall on a watershed to flood flow. The PMP is a deterministic estimate of the theoretical maximum depth of precipitation that can occur at a time of year of a specified area. A rainfall-to-runoff transformation function, as well as runoff characteristics, based on the topographic and drainage system network characteristics and watershed properties are needed to appropriately develop the PMF hydrograph. The PMF hydrograph is a time history of the discharge and serves as the input parameter for other hydraulic models which develop the flow characteristics including flood flow and elevation.
Chattahoochee River The USACE evaluated a PMF routed through Walter F. George using controlled releases yielding a peak discharge at Plant Farley of 664,061 cfs with a maximum water surface elevation of 141.5 ft (Reference 72).
The discharge and stage hydrographs on the Chattahoochee River at Plant Farley are provided in Figure 4-2.
800,000 180.00 Plant Grade Elevation
- 154.S ft NGVD 29 700,000 160.00 140.00 600,000
,, 120.00 500,000 ,,
I 400,000 --L __ +---
_,-;';- --+--I 100.00 80.00 ai" N
0
~
300,000 60.00 200,000 40.00 100,000 20.00 0 20 40 60 80 100 120 140 160 180 Time (hours)
--Discharge ---- Stase - -
- Plant Grade Elevation Figure 4-2: Discharge and Stage Hydrograph for a PMF on the Chattahoochee River Routed through Walter F. George using Controlled Releases Wilson Creek Wilson Creek Is adjacent to Plant Farley to the north and is within in the Chattahoochee River watershed.
Figure 4-3 shows the location of the 7.99 square-mile Wilson Creek watershed relative to the Plant Farley site.
JOSEPH M. FARLEY NUCLEAR POWER PLANT Page 27 of 44 SNC PO No.: SNA31 945-0002, Line 1, Item 764659 RCN: FAR0169.0
SAM NTTF Recommendation 2.1 (Hazard Reevaluations): Flooding October 20, 2015 Southern Nuclear Operating Company, Inc. Version 1.0 Figure 4-3: Wilson Creek Watershed The peak discharge and associated flood levels of Wilson Creek were evaluated in calculation SC-SNC453276-003 (Reference 74) to determine if flooding from Wilson Creek would challenge the site during an extreme storm event. The following subsections describe the PMF hydrologic and hydraulic analyses performed for Wilson Creek. Unless noted otherwise, these subsections reference calculation SC-SNC453276-003.
Wilson Creek PMF Hydro/ogic Analysis HEC-HMS was used to simulate the hydrologic processes of the watershed. The model was developed using three sub-basins. No stream gage data is available for Wilson Creek to allow for model calibration.
Therefore the model was not calibrated and was run for a1 spatially-constant PMP equal to the PMP obtained from HMR 51 and 52 for the storm center. Snyder's method was used for rainfall-runoff transformation. Losses and channel routing were conservatively not included in the model.
PMP storm durations of 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br />, 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br />, and 1 day were considered. The 1-day PMP yielded the largest peak discharges.
Table 4-3 reports the values of peak discharge at HEC-HMS model junctions (shown in Figure 4-3), used as input for the Wilson Creek HEC-RAS model simulation.
Table 4-3: PMF Peak Discharges at the Wilson Creek HEC-HMS Model Junctions Junction Peak Discharge (cfs)
WC10200J 20,314 WC10100J 29,506 OUTLET 32,458 JOSEPH M . FARLEY NUCLEAR POWER PLANT Page 28 of 44 SNC PO No.: SNA31945-0002, Line 1, Item 764659 RCN: FAR0169.0
SAM NTTF Recommendation 2.1 (Hazard Reevaluations): Flooding October 20, 2015 Southern Nuclear Operating Company, Inc. Version 1.0 Wilson Creek PMF Hydraulic Analysis A steady-flow, one-dimensional hydraulic analysis of Wilson Creek was conducted using HEC- RAS. Cross-section geometry was developed using a combination of the DEM developed from Plant Farley LiDAR data (Reference 15) and USGS 10-meter DEM (Reference lla). The geometry of the rail and truck bridge on Wilson Creek obtained from SNC design drawing D-171636 Revision 4 (Reference 71) was coded Into the HEC-RAS model.
The slope for the HEC-RAS model downstream boundary condition was set to 0.00319 ft/ft, which corresponds to the stream slope for the last few downstream cross sections. USGS orthoimagery (Reference llb) and HEC-RAS User's Manual (Reference 76) were used to estimate Manning's n-values and ineffective flow areas. Contraction and expansion coefficients for natural floodplain cross sections were set to 0.1 and 0.3. Contraction and expansion coefficients upstream and downstream of the bridge were set to 0.3 and 0.5.
The peak PMF discharge of 32,458 cfs resulted in a maximum PMF stage just upstream of the rail and truck bridge (HEC-RAS River Station 6639.6) of 140.17 ft NAVD88, corresponding to 140.50 ft NGVD29, which is 14 ft below the plant grade elevation of 154.5 ft NGVD29 (Reference 7). Figure 4-4 shows the water surface elevation profile for the governing PMF computed using HEC-RAS.
Wilson Cleek Plan: WlsonCreek 8112/2015 Whon Creek Mui
,eo IAgond Plant Grade Elevatlon a 154.17 ft NAVO BB= 154.S NGV029 150
_ - - - - - - - - - - - - , WS P"4'
- 1 day Ground 140 130 g
j 120 1
w 110 100 PMF WSE upstream of Rall and Truck Bridge~
90 140,17 ft NAVO 88
- 140.50 ft NGVD29 80 .., --r - --
0 1000 2000 3000 4000 5000 6000 7000 8000 9000 10000 11000 12000 13000 Main Channel Distance (II)
Figure 4-4: Water Surface Elevation Profile for Governing PMF from WIison Creek HEC*RAS Model
- c. Dam Breaches and Failures (b)(3) 16 USC § 8240-1 (d), (b)(4) (b)(7)(F)
- Buford Dam o Hydrologic Failure 8240-1 (dl (b)
(4) (b)(7)(F) o Sunny Day Failure
. . F "I "'
(b....,(,.!:;):;:
16;.::U .::;;==:
C o Se1sm1c a1 ur 8240 _1(d) (bJ( 4), (b)
(7)(F)
JOSEPH M. FARLEY NUCLEAR POWER PLANT Page 29 of 44 SNC PO No.: SNA31945-0002, Line 1, I1em 764659 RCN: FAR0169.0
SAM NTTF Recommendation 2.1 (Hazard Reevaluations): Flooding October 20, 2015 Southern Nuclear Operating Company, Inc. Version 1.0
- Walter F. George Dam b}( )1 U 4o-1(d} (b}(4), ( )( )(
0 0
- West Po nt Dam 0 Hydrologlc Failure (b)(3) 16 USC § 824o,1(d}, (b)(4), (b)(7)
(F) o Sunny Day Failure l(b)(3):16 U.S C. § 824o-1(d), (b)(4), (b)(7)(F)
Table 4 -4: l(b)(3) 16 USC § 8240-1(d), (b)(4), (b)(7)(F) I I
USACE Project Failure Scenario I Peak Discharge (cfs l (D/(3) 1t> u :, l, § 8240-1 (d) (b)(4) (b)({)(~)
Buford Dam Walter F. George Dam West Point Dam JOSEPH M. FARLEY NUCLEAR POWER PLANT Page 30 of44 SNC PO No.: SNA31945-0002, line 1, Item 764659 RCN: FAR0169.0
SAM NTTF Recommendation 2.1 (Hazard Reevaluations): Flooding October 20, 2015 Southern Nuclear Operating Company, Inc. Version 1.0
§ 24o-1( ),( )(4) (b)( )()
( )(3) 16 U Figure 4-5: Discharge and Stage Hydrograph for Governing PMF from m~i"Z"'T"l"'l""l"""'!""ll'i"li-::-,"- , - - - - - - - - . . . . . . 1 o- hydrologlc failure at (b)(JJ-1 U 4o- 1 (d) (b)(4), (b)(7)(F) (d). (b)(4) (b)(7)(F)
- d. Storm Surg Storm surge is the rise of offshore water elevation caused principally by the shear force of the hurricane or tropical depression winds acting on the water surface.
The Chattahoochee and Flint rivers merge at Lake Seminole to form the Apalachicola River, which drains into the Gulf of Mexico. Tidal influence does not extend beyond 25 miles up the Apalachicola River. Plant Farley is well upstream of tidal influences on the Apalachicola River and, therefore, is not susceptible to storm surge flooding (Reference 21).
- e. Seiche Seiche Is an oscillation of t he water surface in an enclosed or semi-enclosed water body Initiated by an external cause.
The Chattahoochee River is not a semi-enclosed water body and, therefore, Plant Farley is not susceptible to seiche f looding.
- f. Tsunami Tsunami Is a series of water waves generated by a rapid, large scale disturbance of a water body due to seismic, landslide or volcanic tsunamigenic sources.
The Chattahoochee and Flint r ivers merge at lake Seminole to form the Apalachicola River, which drains into the Gulf of Mexico. Tidal influence does not extend beyond 25 miles up the Apalachicola River. Plant JOSEPH M. FARLEY NUCLEAR POWER PLANT Page 31 of 44 SNC PO No.: SNA31945-0002, Line 1, Item 764659 RCN: FAR0169.0
SAM NTTF Recommendation 2.1 (Hazard Reevaluations): Flooding October 20, 2015 Southern Nuclear Operating Company, Inc. Version 1.0 Farley is well upstream of tidal influences on the Apalachicola River and, therefore, is not suisceptible to tsunami flooding (Reference 21).
- g. Ice Induced Flooding Ice jams and ice dams can cause flooding by impounding water upstream of a site and subsequently collapsing or downstream of a site impounding and backing up water. There is no method to assess a probable maximum ice jam or ice dam. Therefore, historical records are generally used to determine the most severe historical event in the vicinity of the site.
Icing does not normally occur on the Chattahoochee River at Plant Farley. The only recent incidence of icing occurred in 1961 along the banks in slack water areas. No record of the river being iced over at this location has been found. Therefore, there would be no Interference with the flow of water into the river water intake due to ice. Even if the surface did become frozen there would be no interference with withdrawal of water by the river water intake due to depth of water in river (Reference 7).
- h. Channel Migration or Diversion Flood hazard associated with channel diversion is due to the possible migration either toward the site or away from it. For natural channels adjacent to the site, historical and geomorphlc processes should be reviewed for possible tendency to meander. For man-made channels, canals or diversions used for the conveyance of water located at a site, possible failure of these structures should be considered.
As indicated in NUREG/CR-7046 Section 3.8, there are no well-established predictive models for channel diversions and, therefore, It is not possible to postulate a probable maximum channel diversion event (Reference 4). As part of the Plant Farley analysis, historical records and available studies were reviewed to evaluate whether the adjacent Chattahoochee River has exhibited the tendency to meander towards the site. Available sources Including the Plant Farley FSAR, current and historical topographic maps, and geologic information were reviewed.
Meandering river bends are observed in natural river channels at all scales. The natural flow path adjustments occur so that the sediment transport capacity of the river channel matches the upstream sediment supply rate with deposition or erosion along the channel bed. The channel continually evolves because the upstream rates of water and sediment are continually changing.
The Chattahoochee River reach adjacent to the Plant Farley site is approximately 500 ft wide. There are eleven inline reservoirs on the Chattahoochee River upstream of the site. The closest reservoir to Plant Farley, George W . Andrews Lock and Dam, is approximately 2 miles upstream of the site. The George W.
Andrews Lock and Dam was constructed in 1963 and is operated by the US Army Corps of Engineers (Reference 16). Based on a review of the upstream reservoirs in the watershed, it appears the reservoirs could serve to trap sediment as well as control outflows, which could reduce the tendency of the reach adjacent to Plant Farley to meander (Reference 17). To evaluate whether the reach adjacent to Plant Farley has a tendency to meander, a USGS quad map from 1953 (Reference 11.c.i) was superimposed on current aerial Imagery (2011 NAIP, Reference. 11.b) at the Plant Farley site. Figures 4-6 to 4-8 show that little change has occurred in the alignment of this reach over the past 60 years. Figure 4-9 is the recent 2011 USGS Quadrangle map of the area. This indicates that, perhaps due to the dampening effect of peak flows as well as reduction of the sediments by upstream reservoirs, a very stable channel has developed in this region.
The Chattahoochee River is approximately 0.8 miles to the east of Plant Farley, where the intake for the plant draws a portion of its cooling water supply. Based on discussions with SNC personnel during an April 2, 2013 site visit, the river intake structure is maintained free of sediment and debris build up, however JOSEPH M. FARLEY NUCLEAR POWER PLANT Page 32 of 44 SNC PO No.: SNA31945-0002, Line 1, I1em 764659 RCN: FAR0169.0
SAM NTTF Recommendation 2.1 (Hazard Reevaluations): Flooding October 20, 2015 Southern Nuclear Operating Company, Inc. Version 1.0 large scale dredging operations to prevent channel meandering due to scour or substantial sediment build up have not been necessary at the river intake structure.
Figure 4-6: 1953 USGS Dothan, Al Quadrangle Map JOSEPH M. FARLEY NUCLEAR POWER PLANT Page33 of 44 SNC PO No.: SNA31945-0002, Line 1, Item 764659 RCN: FAR0169.0
SAM NTTF Recommendation 2.1 (Hazard Reevaluations): Flooding October 20, 2015 Southern Nuclear Operating Company, Inc. Version 1.0 Figure 4-7: 2011 NAIP Aerial Imagery JOSEPH M. FARLEY NUCLEAR POWER PLANT Page 34 of44 SNC PO No.: SNA31945-0002, Line 1, Item 764659 RCN: FAR0169.0
SAM NTTF Recommendation 2.1 (Hazard Reevaluations): Floodi ng October 20, 2015 Southern Nuclear Operating Company, Inc. Version 1.0 Figure 4-8: Superposition of 1953 USGS Quadrangle map on 2011 NAIP Aerlal Imagery JOSEPH M. FARLEY NUCLEAR POWER PLANT Page 35 of 44 SNC PO No.: SNA31945*0002, Line 1, Item 764659 RCN: FAR0169.0
SAM NTTF Recommendation 2.1 (Hazard Reevaluations): Flooding October 20, 2015 Southern Nuclear Operating Company, Inc. Version 1.0 EUSGS
....1'>0' U.S. Ol!PAR'TMENT OP nil I NTl!RIOR U . $ . 0601.00ICAL SURVSY
(;USTopo Figure 4-9: 2011 USGS Gordon, AL-GA 7.s* Quadrangle Map
- i. Combined Effect Flood Kontek Vehicle Barrier The Plant Farley safety related buildings are surrounded by 3.5-ft high Kontek Vehicle Barriers (References 79 and 80). Note 2 of SNC Dr.awing D-506768 Version 7.0 Dated August 4, 2013 (Reference 81) describes these barriers as " permanent anti-crash concrete block barriers."
JOSEPH M. FARLEY NUCLEAR POWER PLANT Page 36 of 44 SNC PO No.: SNA31945-0002, Line 1, Item 764659 RCN: FAR0169,0
SAM NTTF Recommendation 2.1 (Hazard Reevaluations): Flooding October 20, 2015 Southern Nuclear Operating Company, Inc. Version 1.0 Wind-Generated Waves Per NUREG/CR-7046 (Reference 4), the 2-year wind speed was applied in the critical direction on top of highest stillwater elevation produced by the governing flooding scenario. The analysis is presented in Calculation SC-SNC453276-005 (Reference 73).
Two fetch lengths from the same Critical Fetch were used in this study. The first fetch length of 4.98 mi, representing the deep open water portion of the Critical Fetch from the edge of the governing PMF flood area to the southern edge of the Plant Farley site, was used to compute the offshore wave characteristics (significant wave height, wave period, and maximum wave height) and to determine the wavelength classification. The second fetch length of 5.08 mi, representing the distance from the edge of the governing PMF flood area to the Plant Farley Kontek Vehicle Barrier, was used to compute the wind setup at the Kontek Vehicle Barrier (Refere1nce 73).
The 2-year wind speed of SO mph at 30 ft above ground was obtained from Figure 1 of ANSI/ANS-2.8-1992 (Refer~nce 5). The topographic data was assembled using LiDAR data (Reference 15) and USGS DEM Data (Reference lla).
Wind-generated wave heights, wave runup, and wave breaking and attenuation were computed using the methods illustrated in EM 1110-2-1100 (Reference 6). Wave runup was computed using methods from USACE CERC-90-4 (Reference 78). Wind setup was estimated using the approach described in EM 1110 1420 (Reference 77). The maximum wave height was determined in accordance with section 7.4.3 of ANSI/ANS 2.8 (Reference 5).
The classification of the wave conditions along the critical fetch was estimated following the approach described in EM-1110-2-1100 (Reference 6). Offshore waves were classified as deep water waves based on the ratio of average depth to the wavelength per EM-1110-2-1100 (Reference 6).
The offshore significant wave height associated with a fetch-limited wave period of 2.9 seconds and a wind velocity of 50.65 mph at 10 m (32.8 ft) above ground was estimated to be 3.94 ft crest to trough, with a maximum (1%) wave height of 6.57 ft crest to trough. The wind setup at the Kontek Vehicle Barrier was estimated to be 0.45 ft.
The governing PMF maximum stillwater depth at the Kontek Vehicle Barrier within the area where incident waves could potentially propagate between the Primary Access Point Building an~ I is r=l tt. The(b)(3) 16 U SC computed wave height above the PMF stillwater level at the Kontek Vehicle Barrier isL : f t: T~ aximumf~~~.?!~
water depth at the Kontek Vehicle Barrier, computed as the sum of maximum PMF Stillwater depth, wind ,., ,w,.,r:
setup, and wave height above the stillwater level, isc:::::]ft, corresponding to a maximµm '!Vater surface (b)(3).16 U S C (b)(3) 16 USC *********** J ft NGVD 29. The maximum water depth at the Kontek Vehicle Barrier incliucli~g-----wave § 824o:1(d), (b) elevation...ofE
§ 824o-1(d}:(bj runup, computed as the sum of maximum PMF Stillwater depth, wind setup, and wave runup, isG ft.,.i6)(3n(rus C corresponding to a maximum water surface elevation of[ 3ftNGV029. _ t,~~'~'S(~
The Kontek Vehict jier height is 3.5 feet, which is larger than the maximum water depth at the Kontek ,., ,L,m,): ( )
1 (b)(3) 6 USC ...Vehlde...8arrier *O * *-* * -* ft,* therefore, the Kontek Vehicle Barrier stops the wave propagation towards the
§ 824o-1(d}: (bf.
safety-related bui ings. Overtopping of the barrier may occur due to wave runup, but with no sustained wave action past the barrier. A summary of the key wave characteristics is provided in Table 4-5.
Table 4-5: Summary of Key Wave Characteristics Offshore Significant Wave Height, ft 3.94 Offshore Maximum Wave Height, ft 6.57 Wind Setup, ft 0.45 JOSEPH M . FARLEY NUCLEAR POWER PLANT Page 37 of44 SNC PO No.: SNA31945-0002, Line 1, Item 764659 RCN: FAR0169.0
SAM NTTF Recommendation 2.1 (Hazard Reevaluations): Floodling October 20, 2015 Southern Nuclear Operating Company, Inc. Version 1.0 PMF Stillwater Elevation at the Kontek Vehicle Barrier, ft NGVD29 (0)(3) 1o U SC § 8240-1 (d) (b)(4) ~
Maximum Depth at Kontek Vehicle Barrier using Offshore Significant Wave Height (b)(7)(F) and Wind Setup, ft Maximum Water Surface Elevation at Kontek Vehicle Barrier using Offshore Significant Wave Height and Wind Setup, ft NGVD29 Maximum Depth at Kontek Vehicle Barrier using Offshore Maximum Wave Height and Wind Setup, ft
~
Maximum Water Surface Elevation at Kontek Vehicle Barrier using Offshore Maximum Wave Height and Wind Setup, ft NGVD29
~
Maximum Depth at the Kontek Vehicle Barrier Including Computed Wave Height at Barrier and Wind Setup, ft Maximum Water Surface Elevation at the Kontek Vehicle Barrier Including Computed Wave Height at Barrier and Wind Setup, ft NGVD29 Maximum Depth at the Kontek Vehicle Barrier Including Wind Setup and Wave Runup, ft Maximum Water Surface Elevation at the Kontek Vehicle Barrier Including Wind Setup and Wave Runup, ft NGVD29
- 5. COMPARISON WITH CURRENT BASIS FLOOD HAZARD The current and reevaluated flood causing mechanisms at the site were compared to assess whether the reevaluated flood hazard is bounded by the current design basis flood elevation. The comparison is provided in Table 5-1.
Table 5-1: Summary Comparison with Current Licensing Basis Flood Hazard Licensing Basis Current Licensing Bounds Flood Causing Basis Flood Hazard Flood Hazard Reevaluation Elevation Reevaluation Mechanism Elevation (NGVD29} (NGVD29} Flood Hazard?
Local Intense 6 inch flood depth Maximum Occurring Water Surface Not Bounded Precipitation outside of the Elevations at Unprotected Openings of turbine building Safety Related Buildings:
=
Auxiliary Unit 1 155.75 ft
=
Auxiliary Unit 2 155.81 ft Containment Unit 1 = 155.23 ft Containment Unit 2 = 155.99 ft Diesel Generator Building= 155.44 ft Service Water Intake Structure= 195.84 ft Flooding in Streams Maximum Occurring Maximum Occurring WSE at the plant Bounded and Rivers WSE at the plant due due to a PMF routed through Walter to Chattahoochee F. George with controlled releases River PMF is 144.2 ft. 141.5 ft.
JOSEPH M . FARLEY NUCLEAR POWER PIANT Page 38 of44 SNC PO No.: SNA31945-0002, Line 1, Item 764659 RCN: FAR0169.0
SAM NTTF Recommendation 2.1 (Hazard Reevaluations): ~looding October 20, 2015 Southern Nuclear Operating Company, Inc. Version 1.0 Licensing Basis Current Licensing Bounds Flood Causing Basis Flood Hazard Flood Hazard Reevaluation Elevation Reevaluation Mechanism Elevation (NGVD29) (NGVD29) Flood Hazard?
Dam Breaches and Maximum Occurring Maximum Occu rring WSE at the plant Not Bounded Failures WSE at t he plant due due to (DJ\->fl ti U ::, l, S 0L40-l \U/ \U)\4/,
\DJ\.)} lb I
to hydrologic dam USC§ ~ ro og~ ra11ure atl +**
failure of Bartletts 8240-1 i ............ * ******************************** .............................. . ..........................
~
(b)(3) 16 USC ..... .. Ferry Dam isF 7tt. (d) (b) ltA\ ,~
§ 824o-1'{d}:-(b)
Combined Effect M aximum Occurring Maximum Occurring WSE including Not Bounded Flood WSE at the plant due wave runup at the Kontek Vehicle to Chattahoochee Barrier along the Critical Fetch due to River PMF plus 50 (b)(3) 16 U SC § 8240-1(d) (b)(4) (b)(7){F)
Storm Surge mnh wave runup Is 1ft.
I
-- Js -
II ,uro10 ft1c ra11ure at I~~~~ 10 u::," s 8240-t(d), (b)(4) (b) 7\!Fl Not addressed in the Not an applicable flood causing Not Applicable CLB mechanism Seiche Not addressed in the Not an applicable flood causing Not Applicable CLB mechanism Tsunami Not addressed in the Not an applicable flood causing Not Applicable CLB mechanism Ice Induced Not addressed in the Not an applicable flood causing Not Applicable Flooding CLB mechanism Channel Migration Screened Out Screened Out Not Applicable of Diversion
- 6. INTERIM EVALUATION AND ACTIONS TAKEN OR PLANNED TO ADDRESS ANY HIGHER FLOODING HAZARDS RELATIVE TO THE DESIGN BASIS The NRC 10 CFR 50.54(f) Request for Information letter dated March 12, 2012 (Reference 2) provides that flood hazard reevaluations are performed using updated flooding hazard information and present-day regulatory guidance and methodologies. Vulnerabilities identified during the flood hazard reevaluations were entered into t he corrective action process and will be dispositioned accordingly.
Plant-specific vulnerabilities based on updated hazard assessments resulted in LIP, Dam Breaches and Failures and Combined Effect flooding levels that exceeded the existing Design Basis flood levels listed in the FSAR (Reference 7) and are conditions beyond the CLB. These do not call into question operability, and need not be reported to the NRC pursuant to 10 CFR 50.72 or 10 CFR 50.9. NRC notification of the flooding reevaluation results and any actions taken in response to them will be reported in the reevaluation report and the integrated assessment, If necessary, required by the 50.54(f) letter.
JOSEPH M . FARLEY NUCLEAR POWER PLANT Page 39 of 44 SNC PO No.: SNA31945-0002, Line 1, Item 764659 RCN: FAR0169.0
SAM NTTF Recommendation 2.1 (Hazard Reevaluations): Flooding October 20, 2015 Southern Nuclear Operating Company, Inc. Version 1.0 Documentation of interim and now final corrective actions to mitigate the Beyond Design Basis values are presented In the following discussions.
LIP The Farley Nuclear Plant Abnormal Operating Procedure for Severe Weather, FNP-O-AOP-21.0 (Reference
- 75) provides procedures to prepare for a LIP event when rainfall within the next 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> is predicted to exceed 6 inches per hour. If LIP conditions are predicted, then management will initiate th-e actions of Appendix VIII, the Intense Precipitation or Site Flooding Contingency.
Appendix VIII provides guidance for when and how to place sandbags, staffing for sandbagging evolution, procedures associated with filling and placing sandbags, where to obtain the sandbags and bagging tools, the location of sand storage, and where to transport the sandbags (specifically doors and diesel fuel oil storage tank areas listed In the "Sand Bag Requirements" table Included In the appendix). Specific direction is provided for how to place sandbags at doors that must remain functional, for the New Fuel doors, East Missile doors and doors that are not required to remain functional. Guidance is also provided on how to remove the sandbags.
Riverine PMF The Farley Nuclear Plant Abnormal Operating Procedure for Severe Weather, FNP-O-AOP-21.0 (Reference
- 75) provides procedures to prepare for a riverine flooding event. A river stage of 95 ft (NGVD29) at the River Water Intake Structure with a projected continued rise initiates the actions described in Appendix I, the High River Level Contingency.
Appendix I provides phone numbers for USACE personnel at Andrews Lock and Dam and Walter F. George Dam to obtain the latest river forecasts. Appendix I also provides projected river stages and flood protection actions to take with regard to those projected river stages. Table 6-1 provides the projected river stages, the maximum riverine PMF elevation and the time to reach those river stages from the 95 ft (NGVD29) initiation stage based on the stage hydrograph developed by USACE provided in Figure 4-5. It is important to note that the site is not inundated during the PMF and safety related buildings are not impact ed. Only with the combined effects of wind-generated! waves on top of the PMF do water surface elevations exceed plant grade, but wave propagation is stopped by the Kontek Vehicle Barrier and does not impact safety related structures.
Table 6-1: River Stages and Preparation Time Projected River Time to Reach Stage (ft. River Stage NGVD29) (hours)*
104 3 112 6 127 14 (b)(3) 16 USC
§ 824o-1(d}:(bJ- - - - - -
(4) (b)(7)(F)
I I r* 53
- Time from river stage 95 ft NGVD29
- Maximum PMF elevation JOSEPH M. FARLEY NUCLEAR POWER PLANT Page 40 of 44 SNC PO No.: SNA31945-0002, Line 1, Item 764659 RCN: FAR0169.0
SAM NTTF Recommendation 2.1 (Hazard Reevaluations): Flooding October 20, 2015 Southern Nuclear Operating Company, Inc. Version 1.0
- 7. REFERENCES
- 1. Nuclear Energy Institute (NEI), Report 12-08. Overview of External Flooding Reevaluations. August 2012.
- 2. U.S. Nuclear Regulatory Commission. Letter to Licensees. Request far Information Pursuant to Title 10 of the Code of Federal Regulations 50.54(f) Regarding Recommendations 2.1, 2.3, and 9.3 of the Near Term Task Force Review of Insights from the Fukushima Dai-ichi Accident. March 12, 2012.
- 3. U.S. Nuclear Regulatory Commission (NRC). 2007. NUREG-0800, "Standard Review Plan for the Review of Safety Analysis Reports for Nuclear Power Plants: LWR Edition - Site Characteristics and Site Parameters (Chapter 2)," ML070400364, March 2007.
- 4. U.S. Nuclear Regulatory Commission (NRC). 2011. NUREG/CR-7046, PNNL-20091, Design-Basis Flood Estimation for Site Characterization at Nuclear Power Plants in the United States of America.
ML11321A195, November 2011.
- 5. American Nuclear Society (ANS). 1992. American National Standard for Determining Design Basis Flooding at Power Reactor Sites. Prepared by the American Nuclear Society Standards Committee Working Group ANSI/ANS-2.8, La Grange Park, Illinois.
- 6. United States Army Corps of Engineers (2008), Engineering Publication EM 1110-2-1100.
- 7. Southern Nuclear Operating Company (2015), "Joseph M. Farley Nuclear Plant, Units 1 & 2 Final Safety Analysis Report (FSAR)". Rev 26.
- 8. AMEC Computer Software Validation and Certification NUK-003; FLO-20.
- 10. FLO-20 Reference Manual, Version 2009.
- 11. U.S. Geological Survey. The National Map Viewer. http://nationalmap.gov The following datasets files were downloaded for the specified extent :
- a. National Elevation Dataset (NED) in 1/3 arc second resolution, ArcGrid format
- b. National Agriculture Imagery Program (NAIP), JPG2000 format
- c. USGS Historic 7.5 minute Quadrangle Maps, PDF format I. Dothan, AL 1953 GeoPDF (Extent, (-85.143, 31.199), (-85.074, 31.246))
ii. Gordon, AL 2011 TM GeoPDF (Extent, (-85.125, 31.25), (-85, 31.125))
- d. National Hydrology Dataset (NHD), File Geodatabase format for ArcGIS 9.3.1
- e. National Landcover Database 2006 (NLCD) - Land Cover, GeoTiff format
- 12. SNC (2012). "Farley Nuclear Plant 50.54(f) Flood Walkdown Report. Report Number SNC425759.
Version 0.
- 13. SNC Plant Farley NTTF 2.3 Walkdown Record Form No. PLANT FARLEY-F-2012-95-01, Version 1.0, Dated November 19, 2012.
- 14. U.S. Weather Bureau (1982), "Application of Probable Maximum Precipitation Estimates - United States East of the 105th Meridian," Hydrometeorological Report No. 52.
- 15. Farley Nuclear Plant LIDAR Topography LAS Format, Supplied April 17, 2013.
JOSEPH M . FARLEY NUCLEAR POWER PLANT Page41 of44 SNC PO No.: SNA31945-0002, Line 1, Item 764659 RCN: FAR0169.0
SAM NTTF Recommendation 2.1 (Hazard Reevaluations): Flooding October 20, 2015 Southern Nuclear Operating Company, Inc. Version 1.0
- 16. U.S. Army Corps of Engineers.(2013) Corps Maps: National Inventory of Dams.
http://geo.usace.army.mil/pgis/f?p=397:12: . Accessed 6/18/13.
- 17. Chattahoochee River Basin Watershed Protection Plan, Environmental Protection Division, Georgia Department of Natural Resources. http://www.gaepd.org/Documents/chatt.html.
- 18. Southern Nuclear Operating Company Calculation Package SC-SNC453276-004 (2013), "Evaluation of Plant Farley Local Intense Precipitation - Severe Accident Management (SAM) for Fukushima Near-Term Task Force (NTTF) Recommendation 2.1 Flooding Re-evaluation".
- 19. SNC Plant Farley General Arrangement Drawings No. 0-507029, Version 2.0, Dated June 11, 2013.
- 20. SNC Plant Farley General Arrangement Drawings No. D- 171331, Version 8.0, Dated December 28, 2012.
- 21. United States Geological Survey Georgia Water Science Center: The Apalachicola-Chattahoochee-Flint (ACF) River National Water Quality Assessment (NAWQA) Program study website.
( http://ga.water.usgs.gov/nawga/basin/index.htm l).
- 22. 0170084, Version 30.0, "General Arrangement-Outside of Buildings".
- 23. 0175066, Version 9.0, "Equipment Location Section B-8".
- 24. D205066, Version 6.0, "Equipment Location Section "B-B" ."
- 25. 0514690, Sheet 4, Version 2.0, "Residual Heat Removal System - Ell Piping and Hanger Isometric".
- 26. D514690, Sheet 2, Version 1.0, "Residual Heat Removal System - Ell Containment Building El.
122'- 9" and Below".
- 27. D515012, Sheet 2, Version 1.0, "Residual Heat Removal System - Ell Containment Building El.
11 105'- 6" *
- 28. DS15012, Sheet 1, Version 1.0, "Residual Heat Removal System - Ell Containment Building El.
105'- 6" ".
- 29. 0514042, Sheet 1, Version 2.0, "Residual Heat Removal System - Ell Containment Building El. 83'-
0" ".
- 30. 0514046, Sheet 1, Version 1.0, "Residual Heat Removal System - Ell Auxiliary Building El. 77'- O" &
83'-0" ".
- 31. 0515285, sheet 2, Version 1.0, "Residual Heat Removal System - Ell Auxiliary Building El. 83' -0" ".
- 32. D515281, sheet 1, Version 2.0, "Residual Heat Removal System - Ell Auxiliary Building El. 78'- O" to 97'-0" ".
- 33. D175058, Version 15.0, "Equipment Locations -Auxiliary Building Area - Plan at 100'-0" & Below".
- 34. D205058, Version 10.0, "Equipment Locations AUX. BLDG. Area Plan EL. 100'-0" & Below".
- 35. D175336, Version 19.0, "Chemical & Volume Control System Piping - Partial Plan AUX. BLDG.".
- 36. D205335, Version 11.0, "Chem. & Vol. Control System Plans EL. 100'-0" -AUX. BLOG.".
- 37. D175344, Version 16.0, "Chem. & Vol. Control System Sections AUX. BLDG.".
- 38. D175343, Version 19.0, "Chemical and Volume Control System Sections AUX. Building".
- 39. 0205339, Version 11.0, "Chem. & Vol. Control Sys. Sections EL. 100'-0" -AUX. BLDG.".
- 40. D175063, Version 18.0, "Equip. Location-AUX. & Control BLDG. Area- Plans at 100'-0" & Below".
JOSEPH M . FARLEY NUCLEAR POWER PLANT Page 42 of44 SNC PO No.: SNA31945-0002, Line 1, Item 764659 RCN: FAR0169.0
SAM NTTF Recommendation 2.1 (Hazard Reevaluations): Floodllng October 20, 2015 Southern Nuclear Operating Company, Inc. Version 1.0
- 41. D205063, Version 16.0, "Equip. Location - AUX. & Control BLDG. Area - Plans at 100'-0" & Below".
- 42. D175308, Version 17.0, "AUX FDWTR SYS- PL AUX BL".
- 43. D205308, Version 16.0, "Auxiliary Feedwater System Plans EL. 100'-0" & 110'-0" -AUX BLDG.".
- 44. D175309, Version 12.0, "AUX FDWTR SYS PL AUX BLDG".
- 45. D205142, Version 19.0, "INST. Locations -AUX & Control BLDG. Area - Plan at EL. 121'-0".
- 46. A181004, Version 45.0, "Functional System Description - Electrical Distribution System".
- 47. D175061, Version 14.0, "Equip. Locations AUX & Control BLDG. Area Plan at 139' -0".
- 48. D205061, Version 13.0, "Equipment Locations AUX & Control BLDG. Area Plan at 139'-0".
- 49. D175062, Version 15.0, "Equip. Locations AUX & Control BLDG. Area Plan at 121'-0".
SO. D205062, Version 12.0, "Equip. Locations AUX & Control BLDG. Area Plan at 121'-0".
- 51. D172171, Version 20.0, "Electrical Equipment Plan Diesel Building".
- 52. D203200, Version 8.0, "Tray & Conduit Layout S.W.I.S Safe Shutdown Raceway Identification &
Location of KAOWOOL Wirap".
- 53. D203201, Version 8.0, "Tray & Conduit Layout S.W.I.S Safe Shutdown Raceway Identification &
Location of KAOWOOL Wrap".
- 54. D175055, Version 20.0, "Equip. Locations AUX. BLDG. Area - Plan at El.155'-0".
- 55. D175056, Version 26.0, "Equip. Locations AUX. BLDG."
- 56. D205056, Version 28.0, "Equipment Locations AUX. BLDG. Area Plan at El.139'-0".
- 57. D177442, Sheet 1, Version 52.0, "Tray and Conduit Layout-Auxiliary Building Elevation 121'-0" -
Area 4".
- 58. D203285, Version 17.0, "Tray and Conduit Layout ELEV. 121'-0" Safe Shutdown Raceway Identification and Location of KAOWOOL Wrap".
- 59. D207430, Version 37.0, "Tray and Conduit Aux. BLDG. Above El. 155'-0" Area 4 West".
- 60. 0177441, Sheet 3, Version 1.0, " Tray & Conduit Layout -AUX BLDG. EL. 121'-0" Area 3".
- 61. D203284, Version 12.0, "Tray & Cond Layout ELEV. 121'-0" Safe Shutdown Raceway ldent and Location of Kaowool Wrap".
- 62. D180562, Version 8.0, "Tray & Conduit Layout ELEV. 121'-0" Safe Shutdown Raceway ID and Location of Kaowool Wrap".
- 63. 0177455, Sheet 1, Version 44.0, "Exposed COND LO Cable Spreading Room".
- 64. 0207455, Sheet 1, Version 37.0, "Exposed Conduit Layout Cable Spreading Room".
- 65. 0207455, Sheet 2, Version 36.0, "Exposed Conduit Layout Cable Spreading Room".
- 66. H12615, Version 6.0, "ARCH Diesel Gen BLDG Roofs & FLR Plan".
- 67. H46159, Version 1.0, "Control Room EL.164'-0" Outline Dimensions for Raised Floor Plan".
- 68. 0175069, Version 25.0, " Equipment Location - AUX. BLOG. Control Room".
- 69. 0205069, Version 25.0, "Equipment Location - AUX. Building Control Room".
JOSEPH M. FARLEY NUCLEAR POWER PLANT Page 43 of44 SNC PO No.: SNA31945-0002, Line 1, Item 764659 RCN: FAR0169.0
SAM NTTF Recommendation 2.1 (Hazard Reevaluations): Flooding October 20, 2015 Southern Nuclear Operating Company, Inc. Version 1.0
- 70. Dl72172, Version 2.0, "Elect SECT & DETS Diesel BLDG".
- 71. Alabama Power Company (1973). Drawing D-171636 Rev. 4 - Rail & Truck Bridge over Rock Creek -
Plan - Elevation. Dated January 9, 1973.
- 72. U.S. Nuclear Regulatory Commission (2015). Joseph M . Farley Nuclear Plant, Units 1 and 2 -
Transmittal of U.S. Army Corps of Engineers Flood Hazard Reevaluation Information (TAC Nos. MF3037 and MF 3038). June 25, 2015.
- 73. Southern Nuclear Operating Company Calculation Package SC-SNC453276-005 (2015), "Plant Farley Wind-Generated Wave Analysis - Severe Accident Management (SAM) for Fukushima Near-Term Task Force (NTTF) Recommendation 2.1 Flooding Re-evaluation".
- 74. Southern Nuclear Operating Company Calculation Package SC-SNC453276-003 (2015), " Farley Probable Maximum Flood Hydraulics - Severe Accident Management (SAM) for Fukushima Near-Term Task Force (NTTF) Recommendation 2.1 Flooding Re-Evaluation".
- 75. Southern Nuclear Operating Company. "Farley Nuclear Plant Abnormal Operating Procedure FNP-O-AOP-21.0: Severe Weather, Revision 41.0. November 3, 2014.
- 76. U.S. Army Corps of Engineers, HEC-RAS River Analysis System, User's Manual, Version 4.1, CPD-68, Hydrologic Engineering Center, January 2010.
- 77. U.S. Army Corps of Engineers (1997). Hydrologic Engineering Requirements for Reservoirs. Engineer Manual (EM) 1110-2-1420.
- 78. USACE (1990). Maximum Periodic Wave Runup on Smooth Slopes. Miscellaneous Paper CERC-90-4.
- 79. Southern Nuclear Ope*rating Company (2010). Document No. U-419516 - J. M. Farley Nluclear Plant
- Unit No. 1 / 2 - Kontek Vehicle Barrier VK8M-20K-50-L. Ver. 2.0.
- 80. Southern Nuclear Operating Company (2010). Document No. U-419517 - J.M. Farley N'uclear Plant
- Unit No. 1 /2 - Kontek Vehicle Barrier VK8M-20K-50-H. Ver. 2.0.
- 81. Southern Nuclear Operating Company (2013). Document No. D-503768 - J.M. Farley Nuclear Plant
- Unit No. 1 /2 - Vehicle Barrier Systems Layout Partial Plans. Ver. 7.0.
- 82. D175057, Sheet 1. Version 34.0, "Equipment Locations - Auxiliary BLDG Area plan at EL. 121'-0".
- 83. D20507, Sheet 1, Version 29.0, "Equipment Locations AUX BLDG. Area Plan at EL. 121'-0".
- 84. D177440, Sheet 1, Version 44.0, "Tray & Cond. Layout AUX BLDG Above EL 121'-0" Area 2".
- 85. D207440, Sheet 1, Version 24.0, "Tray & Conduit Layout Auxiliary Building Above Elevation 121'-0",
Area 2".
- 86. Houze, Robert A., Jr. (2004), "Mesoscale Convective Systems." Review of Geophysics, 42, RG4003/2004. Paper number 2004RG000150.
JOSEPH M . FARLEY NUCLEAR POWER PLANT Page 44 of44 SNC PO No.: SNA31945-0002, Line 1, Item 764659 RCN: FAR0169.0