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#REDIRECT [[JAFP-12-0135, Flooding Walkdown Report - Entergys Response to NRC Request for Information Pursuant to 10CFR50.54(f) Flooding Aspects of Recommendation 2.3 of Near-Term Task Force Review of Insights from the Fukushima Dai-ichi Accident]]
| number = ML12332A379
| issue date = 11/27/2012
| title = James A. FitzPatrick - Flooding Walkdown Report - Entergys Response to NRC Request for Information Pursuant to 10CFR50.54(f) Flooding Aspects of Recommendation 2.3 of Near-Term Task Force Review of Insights from the Fukushima Dai-ichi Accid
| author name = Colomb M J
| author affiliation = Entergy Nuclear Northeast, Entergy Nuclear Operations, Inc
| addressee name =
| addressee affiliation = NRC/Document Control Desk, NRC/NRR
| docket = 05000333
| license number = DPR-059
| contact person =
| case reference number = JAFP-12-0135
| document type = Letter, Report, Miscellaneous
| page count = 25
| project =
| stage = Response to RAI
}}
 
=Text=
{{#Wiki_filter:JAFP-12-0135  
 
November 27, 2012
 
U.S. Nuclear Regulatory Commission
 
ATTN: Document Control Desk
 
11555 Rockville Pike
 
Rockville, MD 20852
 
==SUBJECT:==
Flooding Walkdown Report - Entergy's Response to NRC Request for Information Pursuant to 10 CFR 50.54(f) Regarding the Flooding Aspects  
 
of Recommendation 2.3 of the Near-Term Task Force Review of Insights  
 
from the Fukushima Dai-ichi Accident  
 
James A. FitzPatrick Nuclear Power Plant
 
Docket No. 50-333
 
License No. DPR-59
 
==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 Dai-ichi Accident, dated March 12, 2012 (ML12053A340) 2. Entergy Nuclear Operations, Inc, Response to NRC Request for Information (RFI) Pursuant to 10 CFR 50.54(f) Regarding the Flooding
 
Aspects of Recommendations 2.1 and 2.3 of the Near-Term Task Force
 
Review of Insights from the Fukushima Dai-ichi Accident, dated June 8, 2012, JAFP-12-0063 
 
==Dear Sir or Madam:==
 
On March 12, 2012, the NRC issued Reference 1 requesting information to support the evaluation of the NRC staff recommendations for the Near-Term Task Force (NTTF) review of
 
the accident at the Fukushima Dai-ichi nuclear facility. Enclosure 4 of Reference 1 contains
 
specific requested actions, requested information, and required responses associated with
 
Recommendation 2.3 for flooding walkdowns. Entergy Nuclear Operations, Inc (Entergy)
 
confirmed in Reference 2 that it would use the flooding walkdown procedure (Nuclear Energy
 
Institute 12-07, Guidelines for Performing Verification Walkdowns of Plant Flood Protection
 
Features) as endorsed by the NRC as the basis to conduct the walkdowns and develop the
 
needed information at the James A. FitzPatrick Nuclear Power Plant (JAF).
Pursuant to Required Response 2 of Reference 1, Enclosure 4, Entergy is providing the Flooding Walkdown Report for JAF in Attachment 1.
The new commitment contained in this submittal is contained in Attachment 2.
 
Should you have any questions concerning the contents of this letter, please contact Mr.
Chris Adner, Licensing Manager, at (315) 349-6766.
Entergy Nuclear Northeast Entergy Nuclear Operations, Inc. James A. FitzPatrick NPP
 
P.O. Box 110 Lycoming, NY 13093
 
Tel 315-349-6024 Fax 315-349-6480 Michael J. Colomb Site Vice President JAFP-12-0135 Page 2 of 2 I declareunderpenalty of perjury that the foregoing is true and correct;executed on November 27,2012.Michael J.olomb Site Vice President MPC/CA/kp Attachments:
1.James A.FitzPatrick Nuclear Power Plant Flooding Walkdown Report, JAF-RPT-12-00016 2.List of Regulatory Commitments cc: Regional Administrator, Region I U.S.Nuclear Regulatory Commission 2100 Renaissance Boulevard, Suite 100 King of Prussia, PA 19406-2713 Resident Inspector's Office U.S.Nuclear Regulatory Commission James A.FitzPatrick Nuclear Power Plant P.O.Box 136 Lycoming, NY 13093 Director, Office of Nuclear Reactor Regulation U.S.Nuclear Regulatory Commission Washington, DC 20555-0001 Mr.Mohan.Thadani, Senior Project Manager Plant Licensing Branch 1-1 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation U.S.Nuclear Regulatory Commission Washington, DC 20555-0001 Ms.Bridget Frymire New York State Department of Public Service 3 Empire State Plaza, 10 th Floor Albany, NY 12223 Mr.Francis J.Murray Jr., President New York State Energy and Research Development Authority 17 Columbia Circle Albany, NY 12203-6399 Attachment 1 JAFP-12-0135 James A. FitzPatrick Nuclear Power Plant Flooding Walkdown Report
 
Engineering Report No.JAF-RPT-12-00016 Rev.0 Page 1of 20 ENTERGY NUCLEAR Engineering Report Cover Sheet Engineering Report Title: Flooding Walkdown Submittal Report for Resolution of Fukushima Near-Term Task Force Recommendation 2.3: Flooding NewEngineering Report Type: Revision 0 Cancelled 0 Applicable Site(s)Superseded o IPI 0 ANOI 0 IP2 0 AN02 0 IP3 0 ECH 0 JAF 181 GGNS 0 PNPS 0 RBS 0 VY 0 WF3 0 WPO 0 PLP 0 Report Origin:Entergy 0 Vendor Vendor Document No.: JAF-RPT-12-00016 (6)Quality-Related:
0 YesNo Prepared by:__---::E;..;.;n:.;:.er;;...:c-'-o:.;:.n
_Responsible Engineer (Print Name/Sign)
Date:_Reviewed by: Date:----Design Verified/...:.N...:./.:..;A=--_-:--
_Design Verifier (if required)(Print Name/Sign)
C};1iI:JReviewd (Print Date: I/-'V-,*Reviewed by"': Approved by: t Name/Sign)
Date:
*JAF-RPT-12-00016 OENERCON REV.0 E.allenee-Every project Every day.Page 2 of20 ENGINEERING REPORT JAMES A.FITZPATRICK NUCLEAR POWER STATION WALKDOWN SUBMITTAL REPORT FOR RESOLUTION OF FUKUSHIMA NEAR TERM TASK FORCE RECOMMENDATION 2.3: FLOODING Prepared By: Reviewed By: Peer Reviewed E:3y: Approved By: Date:
___.Date: II-,,,'12.... services).7Date:\\-1"-1"2-Tom elo (Enercon Services)
Flooding Walkdown Submittal Report  for Resolution of Fukushima Near-Term Task Force Recommendation 2.3: Flooding  Engineering Report No. JAF-RPT-12-00016 Rev. 0 Page 3 of 20 TABLE OF CONTENTS Section  Title Page 1.0SCOPE AND OBJECTIVE............................................................................................................
............. 42.0DESIGN BASIS FLOOD HAZARD LEVEL ...............................................................................................
42.1Flood Hazards Identified ......................................................................................................
................... 42.2Assumptions ...................................................................................................................
......................... 62.3Methodology ...................................................................................................................
......................... 72.4Non Confor mance ...............................................................................................................
.................... 73.0EXTERNAL FLOOD PROT ECTION AND MITIGATION FEATURES ...................................................... 73.1Flooding Licens ing Basis ......................................................................................................
................... 73.2Flood Duration ................................................................................................................
......................... 83.3Flood Protection Features .....................................................................................................
.................. 83.4Procedures ....................................................................................................................
.......................... 93.5Adverse Weather ...............................................................................................................
...................... 94.0INTERNAL WARNING SYSTEMS ......................................................................................................
...... 94.1Perimeter Drain Pump Pit High Level............................................................................................
.......... 95.0EFFECTIVENESS OF FLOOD PROTECTION SYSTEMS ....................................................................... 95.1Acceptance Criteria ...........................................................................................................
...................... 95.2Discussion ....................................................................................................................
......................... 116.0IMPLEMENTATION OF WALKDOWNS ................................................................................................. 1 36.1NEI 12-07 Guidance ............................................................................................................
.................. 136.2Team Organization .............................................................................................................
................... 146.3Training Approach .............................................................................................................
.................... 147.0WALKDOWN RESULTS ..............................................................................................................
........... 147.1Results Summary ...............................................................................................................
................... 157.2Deficiencies ..................................................................................................................
......................... 187.3Observations ..................................................................................................................
....................... 187.4Corrective Actions ............................................................................................................
..................... 197.5Flood Protections Featur es Not In spected ......................................................................................
...... 198.0AVAILABLE PHYSICAL MARGIN .....................................................................................................
..... 199.0NEW FLOOD PROTECTION SYSTEMS ................................................................................................ 2 010.0REFERE NCES ....................................................................................................................
..................... 2011.0ATTACHMENTS ...................................................................................................................
................... 20________________________
__________________________________________________
Flooding Walkdown Submittal Report  for Resolution of Fukushima Near-Term Task Force Recommendation 2.3: Flooding  Engineering Report No. JAF-RPT-12-00016 Rev. 0 Page 4 of 20
 
===1.0 SCOPE===
AND OBJECTIVE This report was developed to provide information requested by the United States Nuclear Regulatory Commission (NRC) pursuant to Title 10 of the Code of Federal Regulations, Section 50.54(f) on March 12, 2012 for the James A. Fitzpatrick Nuclear Station (JAF). In response to the NRC request, Entergy performed walkdowns to verify that plant features credited in the current licensing basis (CLB) for protection and mitigation from external flood events are available, functional, and properly maintained. The walkdowns were performed to verify that structures, systems, and components (SSCs), portable flood mitigation equipment, and the procedures needed to install and or operate them during a flood are acceptable and capable of performing thei r design function as cr edited in the CLB. This report presents the findings of the flooding walkdown inspections completed at the JAF Nuclear Station. The walkdowns were completed in accordance with the United States Nuclear Regulatory Commission (NRC) endorsed guidance of NEI 12-07, Rev. 0A, Guidelines for Performing Verification of Plant Flood Protection Features, dated May 31, 2012 and Entergy Nuclear procedure EN-DC-170 that was developed to provide instructions for implementation of the NRC endorsed guidelines. The walkdowns completed at JAF were performed to verify that the structures, systems, and components (SSCs) credited for flood protection are capable of performing their design function as described in the CLB. The walkdowns were also used to verify that plant modifications implemented since original construction, such as changes to topography, do not adversely affect flooding protection. This report identifies the flooding hazards that comprise the CLB and the protection and mitigation features that are credited with preventing the ingress of external water into SSCs important to safety at JAF. The effectiveness of the flood protection features is evaluated against a set of acceptance criteria. Results of the walkdowns, including key findings, available physical margin, and any identified degraded, or nonconforming conditions are addressed and a description of the actions taken or planned to address these conditions is provided. 2.0 DESIGN BASIS FLOOD HAZARD LEVEL 2.1 Flood Hazards Identified Of obvious concern for flooding (due to its proximity) is Lake Ontario. High lake water levels are of concern at the screenwell building and at the shore line. As discussed in the JAF Final Safety Analysis Report (FSAR), the plant is on a slight topographic high. As such, precipitation falling on the site is discharged to Lake Ontario via intermittent streams. In general, the terrain in the area naturally slopes towards Lake Ontario. Roof drains are routed to the lake via the storm drain system. Thus, heavy rain is not a flooding concern for the JAF site.
 
Flooding Walkdown Submittal Report  for Resolution of Fukushima Near-Term Task Force Recommendation 2.3: Flooding  Engineering Report No. JAF-RPT-12-00016 Rev. 0 Page 5 of 20 2.1.1 Lake Ontario From the JAF FSAR Section 2.4.3.2, the probable maximum setup of Lake Ontario at the JAF site was determined to be 4.1 ft. above mean lake water level based on a two dimensional time dependent mathematical model. According to the storm study for the R. E. Ginna Plant (Docket No. 50-244- 5), the maximum probable rainfall on Lake Ontario as a whole is 0.35 ft. The original design basis maximum flood level in the screenwell was obtained by adding the maximum probable short term rise in lake level (4.1 ft.) and maximum probable rainfall on the lake (0.35 ft.) to the maximum contro lled water level (el. 248.0 ft.) resulting in a screenwell flood level of el. 252.5 ft. A later evaluation considered a maximum lake level elevation of 250 ft. (see Section 2.4). This evaluation assessed the effects of a ten thousand year storm and resulted in a revised design basis screenwell flood level of elevation 255 ft. Based on this flood level, the IPEEE (Ref. 10.5) states that the equipment in the lower portions of the screenwell area, and in particular the circulating water pumps and the normal SW pumps, could be affected by a flood.
From the FSAR, Section 2.4.3.
7, the average ground elevation outside the screenhouse is 272.0 ft. Concerning the flooding of the exterior access of the power plant, the maximum wave runup (7.5 ft.), the maximum wind setup (4.1 ft.), and the maximum rainfall of (0.35 ft.) were added to the maximum controlled still water level (248 ft.) resulting in a maximum probable flood level of elevation 260 ft. at the JAF site. The site grade elevation (272.0 ft.) is well above the probable coincident maximum flood level of 260 ft. at the site with a freeboard of 12 ft. Consideration of a maximum lake level of elevation 250 ft. would still result in a flood level of 262 ft.
with approximately 10 ft. of freeboard. 2.1.2 Maximum Probable Rainfall From the JAF Individual Plant Examination for External Events (IPEEE Ref. 10.5), roof and storm drainage at the site was designed on the basis of probable maximum precipitation criteria derived from HMP 33 (Ref. 10.8). In particular, roof drainage was designed assuming rainfall intensities of 3.5 in/hour and 4.0 in/hour for 10-minute durations. Storm drainage was designed assuming a 4.27 in/hour rain intensity.
Probable Maximum Precipitation (PMP) data published by the National Weather Service calls for higher rainfall intensities over shorter time intervals and smaller areas than had previously been considered in the original licensing basis. This could result in higher site flooding levels and greater roof ponding loads than had been used in design bases. Concern over this issue led the NRC to characterize the potential problem as Generic Issue 103. This generic issue was resolved by application of the new PMP criteria to JAF as listed below:
Flooding Walkdown Submittal Report  for Resolution of Fukushima Near-Term Task Force Recommendation 2.3: Flooding  Engineering Report No. JAF-RPT-12-00016 Rev. 0 Page 6 of 20 4.6 in/hour for a 6-hour duration  16 in/hour for a 1-hour duration  24.3 in/hour for a 30-minute duration  34.2 in/hour for a 15-minute duration  65.3 in/hour for a 5-minute duration Although these values exceed the design values, it is noted in the IPEEE that while the capacity of the drainage systems is limited by the flow of water into the drains at low water levels, at higher roof water levels drainage capacity increases. Consequently, it is predicted that PMP rates will not cause such an accumulation of water on the roofs so as to overload them. The IPEEE also states that hydraulic calculations performed using PMPs show the 50 Ib/ft 2 load capacity of the Reactor Building roof will be exceeded only if two of three drains on one side of the roof are blocked and, as a result, the depth of water on the roof exceeds 9.6 in. The IPEEE concludes that the undersized roof drainage on the Reactor and Turbine Buildings will not pose a significant risk. Accordingly, it was judged that Generic Issue 103 was resolved for JAF (Ref. 10.5). 2.1.3 Ground Water Ingress The annular space around the building is prov ided with a circumferential drain at the base of the Reactor Building to collect groundwater and maintain the sand backfill in an unsubmerged condition. Discharge is accomplished by two pumps, one active and one spare, which discharge into the Yard Drainage System which conducts the water to the lake. 2.1.4 Non-Governing Mechanisms Flood mechanisms common at other sites that are not applicable to JAF include the following:  Dam Failures  Ice Blockage  Tsunami  Hurricane
 
===2.2 Assumptions===
 
There are no key assumptions in the design basis flood hazards.
Flooding Walkdown Submittal Report  for Resolution of Fukushima Near-Term Task Force Recommendation 2.3: Flooding  Engineering Report No. JAF-RPT-12-00016 Rev. 0 Page 7 of 20
 
===2.3 Methodology===
 
The design basis flooding hazard was developed considering both PMP and Lake Ontario. 2.4 Non Conformance 2.4.1 Lake Ontario Shore Flood Level As stated in the JAF FSAR Section 2.4.3.5, regulation of Lake Ontario was implemented in April, 1960 at the direction of the International Joint Commission (IJC). One of the primary objectives of the plan of regulation is that the monthly mean level of Lake Ontario shall not exceed elevation 248. The plan of regulation is based upon historic norms for the period 1860 to 1954. Since regulation began, transient conditions in excess of historic norms have caused monthly mean lake level to exceed el evation 248 on a few separate occasions, each of three to four months duration. In each case, levels were lower than would have been experienced under natural control. The highest monthly mean lake level experienced since regulation began was elevat ion 249.1 in May 1973. The original FSAR concluded that the all-time monthly mean high water level, or any other level above elevation 248 would be experienced only if regulation were suspended and Lake Ontario were to revert to natural control; and that it was proper to assume that the maximum storm occurs when the lake stage is at elevation 248, the maximum controlled still water level. Since it has been shown that input in excess of historic norms can occur and can cause lake level to exceed elevation 248 on rare occasions, an additional evaluation was performed. This evaluation concluded that no condition adverse to safety exists with a maximum lake level at or below elevation 250. As discussed in Section 2.1.1, both the 248 ft. and 250 ft. still water level numbers are referenced in the FSAR Section 2.4.3.7. When wave runup, wind setup, and maximum rainfall are added, maximum levels at the shore are calculated as 260 ft. and 262 ft. Although two different still water level numbers are referenced, it is more conservative to use the higher number resulting in a shore flood level of 262 ft. 3.0 EXTERNAL FLOOD PROTECTION AND MITIGATION FEATURES 3.1 Flooding Licensing Basis Flooding events were considered for all modes of plant operation.
Flood contributors include the following:  Local Intense Precipitation  Seiche  Wind-Generated Waves  Wind Setup  Combinations of the above  Ground Water at the Reactor Building Flooding Walkdown Submittal Report  for Resolution of Fukushima Near-Term Task Force Recommendation 2.3: Flooding  Engineering Report No. JAF-RPT-12-00016 Rev. 0 Page 8 of 20
 
===3.2 Flood===
Duration Sustained winds are a key contributor to lake level changes and wave formation. FSAR Section 2.4.3.4 states that the portion of a storm with average hourly winds greater than 50 mph was taken to be the critical portion of the storm for wave formation. The duration of winds 50 mph and greater is 23 hrs.
Maximum probable rainfall has the following impacts on flooding:  Contributor to Lake Level  Causes Flow in the Roof Drain Systems  Creates Intermittent Streams of Runoff to the Lake Precipitation rates and durations ar e discussed above in Section 2.1.2. 3.3 Flood Protection Features 3.3.1 Ground Water Drainage There are no perennial streams located on the JAF site. Precipitation falling on the site is discharged to Lake Ontario via intermittent streams. Although numerous yard drains exist, no credit is taken for these features in the licensing basis. 3.3.2 Roof Drains Roof drains are collected and discharged by gravity to the storm sewer. 3.3.3 Ground Water at Reactor Building The annular space between the exterior wall of the Reactor Building and the surrounding rock is backfilled with a uniform sand material placed under controlled conditions to prevent excessive compaction. This material and method of placement ensures the free movement of the Reactor Building with respect to the surrounding rock during all seismic disturbances. To ensure the maintenance of this material in its as-placed condition, the annular space around the building is provided with a circumferential drain at the base of the Reactor Building to collect groundwater and maintain the sand in an unsubmerged condition. Drainage is accomplished by two perimeter drain pumps, one active and one spare, which discharge into the Yard Drainage System which conducts the water to the lake. 3.3.4 Reactor Building and Conduit Seals The Reactor Building is a poured-in-place reinforced concrete structure up to the refueling floor. Pre-formed water stops are incorporated in all construction joints below grade for watertightness.
Flooding Walkdown Submittal Report  for Resolution of Fukushima Near-Term Task Force Recommendation 2.3: Flooding  Engineering Report No. JAF-RPT-12-00016 Rev. 0 Page 9 of 20 Conduits that penetrate the Reactor Building below grade are sealed to prevent ground water intrusion into the building. 3.4 Procedures The site severe weather procedure requires that adequate dewatering pumps, sandbags, and personnel to assist be av ailable and prestaged. The procedure does not provide specific flood levels that trigger these actions, and the use of sandbags and dewatering pumps is not part of the flood protection CLB. 3.5 Adverse Weather There are no adverse weather conditions concurrent with any flood protection features and associated actions as part of the CLB. 4.0 INTERNAL WARNING SYSTEMS 4.1 Perimeter Drain Pump Pit High Level Perimeter Drain Pumps 75P-4A and 75P-4B (one primary and one standby) ensure that the annular space around the building remains dry. A circumferential drain at the base of the Reactor Building collects groundwater that these pumps discharge to the storm sewer system. Failure of the primary pump would result in operation of the standby pump. Failure of both pumps would result in high level that triggers a control room alarm, "09-6-1-1 PERIMETER DRN PMP TROUBLE". There are no automatic actions associated with this alarm. Manual actions involve troubleshooting and restoring pumps to operability. In addition to the alarm discussed above, pump performance is monitored by the Chemistry Department. Data is reviewed for pump run time and total flow volume on a weekly basis. 5.0 EFFECTIVENESS OF FLOOD PROTECTION SYSTEMS 5.1 Acceptance Criteria Acceptance criteria were established to allow ve rification that each feature was available and functional. The criteria varied based on t he type of feature as discussed below. 5.1.1 Manhole Conduit Seals Manhole 1 conduit seals were inspected to the following acceptance criteria:  Seals show no sign of damage that would pr event them from perfo rming their function  Manhole sump pump functions when require d with no signs of damage that could prevent operation.
Flooding Walkdown Submittal Report  for Resolution of Fukushima Near-Term Task Force Recommendation 2.3: Flooding  Engineering Report No. JAF-RPT-12-00016 Rev. 0 Page 10 of 20 The conduit seals and sump pump were evaluated by general visual inspection from within the manhole. Each conduit that routes to the Reactor Building was visually inspected, and photographs were taken from multiple angles. The sump pump and power source were also visually inspected and photographed. 5.1.2 Yard Areas The yard areas were inspected to the following acceptance criteria:  No topography changes, including security ba rrier installations, that adversely affect the site drainage plan  Verify that there are no added structures, security barriers, fences, etc., not shown on design drawings The site yard areas were separated into f our quadrants for convenience. Natural drain paths and intermittent streams were followed to their discharge point at the lake noting any features of interest. 5.1.3 Perimeter Drain Pumps The acceptance criteria for the perimeter drain pumps included the following:  No sign of damage that could prevent function  Overall physical condition of pump and parts acceptable It should be noted that the perimet er drain pump pit is a confined space. As such, it was considered a restricted access area by t he plant safety department, and a walkdown and inspection was not performed. S ee Section 7.5 for additional detail. 5.1.4 Screenwell Building The screenwell building was inspected to the following acceptance criteria:  No damage to integrity of slab at 255' elevation  All safety related equipment mounted above the floor elevation The Screenwell Building walkdown focused on the 255' elevation (design basis flood level for the screenwell building). T he slabs that make up this elevation were visually inspected for any structural issues. Safety related equipment location above this elevation was also confirmed.
Flooding Walkdown Submittal Report  for Resolution of Fukushima Near-Term Task Force Recommendation 2.3: Flooding  Engineering Report No. JAF-RPT-12-00016 Rev. 0 Page 11 of 20
 
====5.1.5 Shoreline====
Headwalls The shoreline headwalls were inspected to the following acceptance criteria:  Free from obstructions and blockages  No scouring or undermining  Discharge pipe above shore line rock  Discharge pipe diameter matches drawings The walkdown of these features included a visual inspection and photographs of the shoreline and features along wit h dimensional verification of the discharge pipe size. 5.1.6 Roof Drains Roof drains were inspected to the following acceptance criteria:  Drain is in good condition wit h no signs of degradation    No foreign material obstructions in the drain path The drain walkdowns included general visual inspections and photographs from multiple angles. 
 
===5.2 Discussion===
This section addresses the overall effectiveness of the plant's flood protection features to perform their credited functions during a variety of site conditions. Key questions being addressed include:  Is the barrier system available?  Is the barrier system functional?  Are operator actions feasible?  Could other existing plant equipment, structur es, and procedures mitigate the effects of an external flood under a variet y of plant configurations?  Are there additional existing plant struct ures, systems, components, and procedures that are not part of the flooding CL B and that could be used to mitigate an external flood. 5.2.1 Manhole Conduit Seals Manhole 1 contains eight conduits that are routed below grade to the Reactor Building. The conduits are internally sealed at the manhole to prevent water intrusion into the Reactor Building. The conduit seals are available and functional though the material condition requires further evaluation (s ee Walkdown Results Section below). By design, the sump pump in  Manhole 1 (Section 5.1.1) prevents the water level from reaching the elevation of the conduit seals. Should this sump pump fail, a temporary Flooding Walkdown Submittal Report  for Resolution of Fukushima Near-Term Task Force Recommendation 2.3: Flooding  Engineering Report No. JAF-RPT-12-00016 Rev. 0 Page 12 of 20 pump could be used to maintain the water level in Manhole 1 below the level of the conduit seals. The existing Manhole 1 sump pump and the use of a temporary pump are not part of the flooding CLB. 5.2.2 Yard Areas From the FSAR Section 12.3.1, the yard grade surroundi ng the Reactor Bu ilding structure is at elevation 271 ft. - 6 in. As discussed in the FSAR Section 2.4.1, precipitation falling on the site is discharged to Lake Ontario via intermittent streams. These streams are available and functional. In addition to the intermittent streams, a series of catch basins are located throughout the plant yard area that channel rain water into a storm sewer (also known as storm drains) system. However, yard area rainwater collection into this storm sewer system is not discussed in the CLB. 5.2.3 Perimeter Drain Pumps The FSAR Section 12.3.1 discusses these pumps and their function to maintain the backfill around the Reactor Building in an unsubmerged state. The perimeter drain pump pit was considered a restricted access area, thus a walkdown and inspection was not performed. However, the feature is considered available and functional based on no high level alarm existing for the perimeter drain sump. In addition, pump performance is monitored on a weekly basis by the plant chemistry department as part of the tritium detection program. The pumps operate automatically based on level switches. No operator actions are required except for responding to any high level alarms. Should the sump pumps fail, a temporary pump could be used to maintain the water level in the perimeter drain sump below the high level alarm.
Use of a temporary pump is not part of the flooding CLB. 5.2.4 Screenwell Building As discussed in the FSAR Section 2.4.3.2, the maximum probable flood level at the screenwell is elevation 255 ft. This flood level coincides with the top of the floor slab at this level. This barrier is available and functional with no operat or actions required. There are no other existing plant equipment, structures, or procedures that could mitigate the effects of an external flood at the screenwell house. Existing procedures focus on loss of level at the intake or high differential level across the screens. No procedures related to high level conditions in the screenwell were found to exist.
Flooding Walkdown Submittal Report  for Resolution of Fukushima Near-Term Task Force Recommendation 2.3: Flooding  Engineering Report No. JAF-RPT-12-00016 Rev. 0 Page 13 of 20
 
====5.2.5 Shoreline====
Headwalls The headwalls at the shoreline are where water from the site is discharged into Lake Ontario. The elevation difference between the site yard areas and the lake flood level acts to provide a natural flood barrier. This barrier is available and functional. No operator action is required. There are no other existing plant equipment, structures, or procedures that could mitigate the effects of an external flood at the shoreline nor are any required. The elevation difference is sufficient to prevent high lake level flooding from impacting the site. 5.2.6 Roof Drains The Turbine and Reactor Building roof drains discharge rain water to the storm sewer system. These systems are available and functi onal. No operator ac tions are required. There are no other existing plant equipment, structures, or procedures that could mitigate the effects of the maximum probable precipitation and the impact on roof structures. The IPEEE evaluated the roof drains and concluded that maximum probable precipitation events do not pose a significant risk. 6.0 IMPLEMENTATION OF WALKDOWNS 6.1 NEI 12-07 Guidance The verification walkdowns were performed in accordance with the NRC endorsed guidance of NEI 12-07, Rev. 0A, "Guidelines for Perf orming Verification Walkdowns of Plant Flood Protection Features" dated May 31, 2012, and Entergy Nuclear procedure EN-DC-170 that was developed to provide instructions for implementation of the NRC endorsed guidelines. Additional guidance for implementation was also obtained from the Flooding Walkdown Frequently Asked Questions (FAQs) and NRC responses, which are based on discussions between NEI and the NRC. The basis for establishing the walkdown scope and the flood protection features included the preparation of a walkdown list in accordance wit h the guidance provided in Section 4 of NEI 12-07. As part of this preparation, the CLB was reviewed to determine the flood protection features and actions that are necessary to prevent an external flooding event at the site from adversely impacting safety-related SSCs. In addition to the identification of passive and active protection features, existing site and Entergy corporate procedures were reviewed to determine if any procedures were necessary to ensure existing flood protection features would be functional in the event of a flood at the site. Walkdown packages were prepared in accordance with the guidance provided in NEI Section 5.2 and the walkdown team personnel were selected based on the requirements provided in Section 5.3 of NEI 12-07.
Flooding Walkdown Submittal Report  for Resolution of Fukushima Near-Term Task Force Recommendation 2.3: Flooding  Engineering Report No. JAF-RPT-12-00016 Rev. 0 Page 14 of 20 Prior to each walkdown, a pre-job brief was conducted. Walkdown results were documented in accordance with the recommendations of Section 7 of NEI 12-07 on the Flooding Walkdown Record Form provided in Attachment 9.3 of EN-DC-170. The walkdown record form provided in Attachment 9.3 is consistent with the record form template provided in Appendix B of NEI 12-07. 6.2 Team Organization Consistent with Section 5.3 of NEI 12-07, the JAF flooding walkdown team consisted of three members with complimentary background and skills.
The walkdown team was supplemented as required by plant maintenance personnel. 6.3 Training Approach Consistent with Section 5.3 of NEI 12-07 and Section 4.1 of EN-DC-170, personnel selected to perform walkdown inspection activities we re experienced and knowledgeable of the site CLB. Personnel were also trained to perform the visual inspections and met the knowledge requirements specified in EN-DC-170 and Appendix C of NEI 12-07.
Team members associated with the flooding walkdowns also satisfactorily completed the NANTEL Generic Verification Walkdowns of Plant Flood Protection Features lesson and were knowledgeable of the 10 CFR 50.54(f) lette r dated March 12, 2012. Plant maintenance personnel who supplemented the walkdown teams did not need to be qualified to the aforem entioned requirements. 7.0 WALKDOWN RESULTS Features inspected via walkdown fall into the categories as listed in Table 1 below.
Table 1 Total Features (by Category) Category Inspected Future Inspection Passive Incorporated 28 1 Passive Temporary 0 0 Active Incorporated 0 2 Active Temporary 0 0 Results from the walkdowns of the flood protection features are discussed below. These results include key findings; any degraded, non-conforming, or unanal yzed conditions; and any actions taken or planned to address conditions where required.
Flooding Walkdown Submittal Report  for Resolution of Fukushima Near-Term Task Force Recommendation 2.3: Flooding  Engineering Report No. JAF-RPT-12-00016 Rev. 0 Page 15 of 20
 
===7.1 Results===
Summary 7.1.1 Manhole Conduit Seals Eight conduits in Manhole 1 are routed below grade to the Reactor Building. These conduits are sealed internally at the manhole end. The conduit seals were inspected, and close-up photographs were taken. The inspection of the manhole revealed the following:  Uneven patchwork application of conduit seali ng material at the conduits leading to the Reactor Building. Significant corrosion of some of t he armored cables entering the conduits. Water appeared to be seeping from the area where an armored cable entered a conduit. Exposed portions of the conduit sleeves appeared to be in acceptable condition. Manhole sump pump appeared to be in worki ng order. Water level was below the level at which the pump would be expected to operate. No signs of degradation. The inspection results concluded the following for this manhole:  Based on the manhole water level and pum p appearance, the sump pump appears to be operating properly. The material condition at the conduit seal s is not acceptable based on the description above. The integrity of the penetrati on seals could not be visually verified due to the uneven patchwork appearance of the seal material. Water seepage from the armored cable/seal penet ration area is indication of potential seal or armor integrity failure. Overall, should flooding of Manhole 1 o ccur to a level above the conduits, the degraded condition would not likely result in significant water penetration into the Reactor Building. This observation was documented in a condition report. In addition, two earlier condition reports already relate to this topic. Walkdowns of Manhole 2 were not performed. Completion of this walkdown activity is being tracked by a condition report. See Section 7.4 below.
Flooding Walkdown Submittal Report  for Resolution of Fukushima Near-Term Task Force Recommendation 2.3: Flooding  Engineering Report No. JAF-RPT-12-00016 Rev. 0 Page 16 of 20 7.1.2 Yard Areas The yard areas were inspected via walkdown. The licensing basis states that precipitation on the site is carried away via intermittent streams. For convenience, the plant yard areas were divided into four quadrants (North East, South East, North Wes t, and South West). The goals of the walkdown included:  Verify no topography changes, including security barrier installations, adversely affect the site drainage plan. Verify there are no added structures, securi ty barriers, fences , etc. not shown on design drawings. The results of the walkdown confirmed that the above conditions were met. No degraded, non-conforming, or unanalyzed conditions were discovered. No condition reports were written. It should also be noted that in addition to intermittent streams, the site contains a yard drainage system (storm sewer) with numerous catch basins. However, this system is not credited in the licensing basis for removal of gr ound precipitation. 7.1.3 Perimeter Drain Pumps The perimeter drain pump pit was considered a restricted access area, thus a walkdown and inspection was not performed. Completion of this walkdown activity is being tracked by a condition report. A video inspection of the East and West drain pipes was performed in 2010. This video confirmed that the pi pe integrity is sound. 7.1.4 Screenwell Building The screenwell building was inspected via walkdown. The focus of the inspection was the 255 ft. elevation equivalent to the screenwell flood level. The goals of the walkdown included:  Verify adequate structural in tegrity of the concrete sl abs at the 255 ft. elevation  Confirm that all safety related equipment is located above the level of the floor and would not be impacted by a fl ood at the 255 ft. elevation The results of the walkdown confirmed that the above conditions were met. No degraded, non-conforming, or unanalyzed conditions were discovered. No condition reports were written.
Flooding Walkdown Submittal Report  for Resolution of Fukushima Near-Term Task Force Recommendation 2.3: Flooding  Engineering Report No. JAF-RPT-12-00016 Rev. 0 Page 17 of 20
 
====7.1.5 Shoreline====
Headwalls The shoreline headwalls were inspected vi a walkdown. The goals of the inspection included the following. Headwall pipe free from obstructions and blockages  No scouring or undermining  Confirm discharge pipe above shore line rock  Confirm discharge pipe diameter matches drawings The walkdown of these features included a visual inspection and photographs of the shoreline and features along with dimensional verification of the discharge pipe size. The results of the walkdown confirmed that the above conditions were met. No degraded, non-conforming, or unanalyzed conditions were discovered. No condition reports were written. 7.1.6 Roof Drains Roof drains were inspected via walkdown. The goals of the inspection included the following. Drain is in good condition wit h no signs of degradation    No foreign material obstructions in the drain path A total of 20 roof drains were inspected (10 on the turbine building, 6 on the Reactor Building, and 4 on the MG set room roofs. Numerous degraded conditions were found and are summarized below. The two drains on the east MG set room roof were significantly clogged with debris around the dome. A piece of one of the dom es was found on the roof near the drain. A few of the turbine building roof drains had debris buildup caus ing partial blockage and allowing ponding of water around the drain. Numerous domes over the drains (debris guards) were broken or missing sections (spars).
Flooding Walkdown Submittal Report  for Resolution of Fukushima Near-Term Task Force Recommendation 2.3: Flooding  Engineering Report No. JAF-RPT-12-00016 Rev. 0 Page 18 of 20 Most of the domes on the turbine building roof (and some on the Reactor Building roof) were not properly secured to the drain section on the roof (clamp ring). Most of the turbine building roof ground wires were im properly installed contributing to this problem. The degraded and non-conforming conditions described above are documented in condition reports.
 
===7.2 Deficiencies===
The following is a description of the deficiencies as determined by the Condition Report Process. Engineering is in the process of dispositioning the condition reports. 7.2.1 MG Set Room Roof Drains Partially clogged and degr aded roof drains were observed on the MG Set roof. No standing water was observed. It is reasonable to conclude that the drains were still functional although at a reduced capacity. Thus, the r oof structure remained functional. 7.2.2 Reactor Building Roof Drains Degraded roof drains were observed on the R eactor Building roof. It is reasonable to conclude that the drains were still functional. Thus, the roof structure remained functional. 7.2.3 Turbine Building Roof Drains Partially clogged and degraded roof drains were observed on the Turbine Building roof.
Minor standing water was observed. It is reasonable to conclude that the drains were still functional although at a reduced capacity. Thus , the roof structure remained functional. 7.2.4 Manhole 1 Material Condition Uneven patchwork application of conduit seali ng material was observed at the conduits leading to the Reactor Building.
Significant corrosion of some of the armored cables entering the conduits was also observed. Water appear ed to be seeping from the area where an armored cable entered a conduit.
Overall, should flooding of Manhole 1 occur to a level above the conduits, the degraded condition would not likely result in significant water penetration into the Reactor Building.
Thus, the water intrusion would be within the capability of the ar ea floor drain system.
 
===7.3 Observations===
 
All observations from the walkdowns have been captured in condition reports.
Flooding Walkdown Submittal Report  for Resolution of Fukushima Near-Term Task Force Recommendation 2.3: Flooding  Engineering Report No. JAF-RPT-12-00016 Rev. 0 Page 19 of 20
 
===7.4 Corrective===
Actions For each of the Condition Reports a Work Order has been assigned to resolve the identified condition. 7.5 Flood Protections Fe atures Not Inspected The flood protection features list ed below were not inspected. 7.5.1 Perimeter Drain Pump Pit Access to pumps 75P-4 A/B in the perimeter drain pump pit is through vertical 30" diameter pipe that is over 40 ft. long. Entry into this pit requires special rigging to allow the worker to be lowered in a harness by a hoist. This feature is classified as Restricted Access as it is located in a confined space. The restricted access of this feature is being tracked by a condition report. The schedule for inspection is November 1, 2014. The schedule for the future inspection is acceptable based on the following:  Remote inspection of the drain pipes (east and west) was performed in 2010. The drain pipe was clear and the integrity was sound. Pump performance is monitored by the Chemistry Department on a weekly basis. Data is reviewed for pump run time and total flow volume. 7.5.2 Manhole 2 Access into Manhole 2 requires confined space entry. During the team walkdown period (refueling outage), site support was not available for this confined space entry, thus this feature is considered restricted access. The restricted access of this feature is being tracked by a condition report. The site is schedule to perform this walkdown on October 30, 2013 as part of the next scheduled PM for the manhole. 7.5.3 No flood protection features were considered inaccessible. 8.0 AVAILABLE PHYSICAL MARGIN As indicated in Section 3.12 of NEI 12-07, Rev. 0A, the NRC is no longer expecting the Recommendation 2.3: Flooding Walkdowns to include an evaluation of the cliff-edge effects at the site. The Available Physical Margin (APM) has been determined and documented on the walkdown record forms. The APMs provided on the walkdown record forms will allow flood hazard reevaluations completed in response to Recommendation 2.1: Flooding to be completed. No APMs documented in the record forms were considered to be small APMs at JAF.
Flooding Walkdown Submittal Report  for Resolution of Fukushima Near-Term Task Force Recommendation 2.3: Flooding  Engineering Report No. JAF-RPT-12-00016 Rev. 0 Page 20 of 20 9.0 NEW FLOOD PROTECTION SYSTEMS There are no planned or newly installed flood protection systems or flood mitigation measures including flood barriers that further enhance the flood protection. The flooding walkdowns have not resulted in the need for any changes.
 
==10.0 REFERENCES==
10.1 NRC Letter to Licensees, dated March 12, 2012, "Request for Information Pursuant  to Title 10 of the Code of Federal Regulat ions 50.54(f) Regar ding Recommendations 2.1,2.3, and 9.3 of the Near Term Task Force Review of Insights from the Fukushima Daiichi Accident." 10.2 Guidelines for Performing Verification Wa lkdowns of Plant Flood Protection Features (NEI 12-07 [Rev. 0-A]), NEI, dated May 2012. 10.3 Regulatory Issues Summary 2005-20, Revi sion 1, Revision to NRC Inspection Manual Part 9900 Technical Guidance, "Operability Conditions Adverse to Quality or Safety." 10.4 JAF Final Safety Analysis Report Rev. 3, Dated 4/11/2011 10.5 JAF-RPT-MISC-02211, Rev. 0, JAF-Individual Plant Examination for External Events, Dated 6/27/1996 10.7 10CFR50.65, "Requirements for Monitoring the Effectiveness of Maintenance at Nuclear Power Plants" (Maintenance Rule) 10.8 National Weather Service, "Seasonal Variation of the Probable Ma ximum Precipitation East of the 105th Meridian for Areas from 10 to l000 Square Miles and Durations of 6, 12, 24, and 48 hours", Hydrometeorological Report No. 33, 1956 11.0 ATTACHMENTS None ATTACHMENT 2 JAFP-12-0135 List of Regulatory Commitments
 
JAFP-12-0135 Page 1 of 1 List of Regulatory Commitments The following table identifies those actions committ ed to by Entergy in th is document. Any other statements in this submittal are provided for information purposes and are not considered to be regulatory commitments.
TYPE (Check One)
COMMITMENT ONE-TIME ACTION CONTINUING COMPLIANCE SCHEDULED COMPLETION DATE (If Required)
Entergy will perform inspections of equipment that could not be inspected as identified in
 
Section 7.5 of the Flooding Walkdown Report. November 1, 2014}}

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