ML18086A218
| ML18086A218 | |
| Person / Time | |
|---|---|
| Site: | Palisades  |
| Issue date: | 05/03/2018 |
| From: | Joseph Sebrosky Beyond-Design-Basis Management Branch |
| To: | Entergy Nuclear Operations |
| Sebrosky J | |
| References | |
| Download: ML18086A218 (4) | |
Text
UNITED STATES NUCLEAR REGULATORY COMMISSION WASHINGTON, D.C. 20555-0001 May 3, 2018 Vice President, Operations Entergy Nuclear Operations, Inc.
Palisades Nuclear Plant 27780 Blue Star Memorial Highway Covert, Ml 49043-9530
SUBJECT:
PALISADES NUCLEAR PLANT - CORRECTION LETTER FOR STAFF ASSESSMENTS ASSOCIATED WITH RESPONSE TO 10 CFR 50.54(f)
INFORMATION REQUEST - FLOOD-CAUSING MECHANISM REEVALUATION
Dear Sir or Madam:
The purpose of this letter is to provide corrections to two staff assessments the U.S. Nuclear Regulatory Commission (NRC) issued associated with an Entergy Nuclear Operations, Inc.
(Entergy, the licensee) letter dated March 11, 2015 (Agencywide Documents Access and Management System (ADAMS) Accession No. ML15114A209). Entergy's March 11, 2015, letter provided the response for Palisades Nuclear Plant (Palisades) to a March 12, 2012, NRC request for information that was issued under Title 10 of the Code of Federal Regulations, Section 50.54(f). The NRC staff assessments that are being corrected are dated December 23, 2015, and February 14, 2018 (ADAMS Accession Nos. ML15356A765 and ML18037A625, respectively).
Correction to Discussion of Palisades Current Design Basis Table 1 and Table 3.1-1 of the NRC staff's letters dated December 23, 2015, and February 14, 2018, respectively, state the following regarding storm surge:
Flood Mechanism Stillwater Elevations, feet Associated Effects, Current Design Basis (ft.) National Geodetic ft. (COB) Flood Vertical Datum of 1929 Elevation, ft.
(NGVD29) NGVD29 Storm Surge 594.1 8 602.1 In addition, Section 3.5 of the NRC staff's February 14, 2018, letter states the following regarding the Palisades COB:
The COB probable maximum flood elevation for storm surge is based on a stillwater-surface elevation of 594.1 ft. NGVD29, and an elevation of 602.1 ft.
NGVD 29 including wind waves and runup at the lakeward side of the circulation water pipes. The COB design wave height is 8-ft., producing a combined COB total water elevation of elevation 602.1 ft. NGVD29 along the lakeward side of the circulation water pipe.
The above descriptions are not an accurate reflection of the Palisades COB and the associated effects. As stated in Section 3.9.2.1. 7 of the licensee's March 11, 2015, flood hazard reevaluation report (FHRR), wave runup height is not measured as height above the stillwater
elevation but is instead measured from the ground elevation near the Screenhouse/lntake Structure.
Table 1 and Table 3.1-1 of the staff's assessment dated December 23, 2015, and February 14, 2018, respectively, are corrected as follows:
Stillwater Elevation, ft. National Geodetic Current Design Basis Vertical Datum of Associated (COB) Flood Elevation, ft.
Flood Mechanism 1929 (NGVD29} Effects, ft. NGVD29 Storm Surge at the g ~
Screen house/Intake 594.1 (See Note 1) 597.0 (See Note 1)
Structure Storm Surge at Not included ~
locations other than at 594.1 in the COB the Screenhouse/lntake (See Note 2) 594.1 Structure Note 1: The licensee's COB includes an evaluation of wave runup (associated effects) at the Screenhouse/lntake Structure. The wave runup is estimated as 8 ft. above the ground surface elevation at that location (elevation 589.0 ft. NGVD29). This results in a maximum COB elevation of 597.0 ft. NGVD29 at the Screenhouse/lntake Structure.
Note 2: The Screenhouse/lntake Structure was the focal point of the COB analysis for the storm surge flood-causing mechanism. Associated effects were only calculated at this structure. At other locations, the Palisades COB elevation for the storm surge flood-causing mechanism is equal to the stillwater elevation.
The staff also corrects Section 3.5 of the February 14, 2018, letter with the following replacement text:
The Palisades COB includes an evaluation of the dynamic effect of wave run-up to a height of 597.0 ft NGVD29 at the Screen House/Intake Structure, which is capable of withstanding the loads. The COB for Palisades evaluated the impact of stillwater storm surge flooding of 594.1 feet on the safety-related service water pumps. The licensee concluded that the service water pumps would be able to perform their intended safety-related function under these flooding conditions.
The staff notes that Table 2, and Table 4.1-1, of the staff's assessment letters dated December 23, 2015, and February 14, 2018, remain correct and are unchanged. These tables provide information regarding the reevaluated hazard elevations for flood-causing mechanisms not bounded by the Palisades COB and include the following information:
Flood Mechanism Stillwater Associated Reevaluated Hazard Elevations, ft. Effects, ft. Elevation, ft.
NGVD29 NGVD29 Storm Surge (H.4 Combined 593.9 8.3 602.2 Flood Event): Lakeward of Circulation Water Pipes Landward of Circulation Water 593.9 0.4 594.3 Pipes Landward of Turbine Buildinq 593.9 0.4 594.3 North of Turbine Buildinq 593.9 1.1 595.0 The licensee is expected to apply information contained in Table 2 and Table 4.1-1 associated with a storm surge flood-causing mechanism as part of their flooding mitigation strategies assessment, and the flooding focused evaluation or integrated assessment, as appropriate.
Correction to Table 3.2-1 of the Staff Assessment Dated February 14, 2018 Table 3.2-1 of the staff assessment dated February 14, 2018, is corrected as follows regarding Manhole #4:
ID Description Ground Maximum Maximum Time to Bounded (B) or Number Surface Flood Flood Maximum Not Bounded (NB)
Elevation, Elevation, Depth, ft. Flood ft. ft. Elevation NGVD29 NGVD29 (hours) 28 Manhole #4 623.9 626.1 2.2 M NB (East of 0.2 Containment Building)
The staff found the licensee estimate of the time to maximum flood elevation for this location to be reasonable. This duration is 0.2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br />, not 0.5 hours5.787037e-5 days <br />0.00139 hours <br />8.267196e-6 weeks <br />1.9025e-6 months <br /> as previously reported.
If you have any questions, please contact me at (301) 415-1132 or via e-mail at Joseph.Sebrosky@nrc.gov.
Sin~
seph M. Se rosky, Seni Pro* ct Manager yond-Desi n-Basis Management Branch ivision of Licensing Projects Office of Nuclear Reactor Regulation Docket No. 50-255 cc: Distribution via Listserv
ML18086A218 *via e-mail OFFICE NRR/DLP/PBMB/PM NRR/DLP/PBMB/LA NRO/DSENRHM/BC*
NAME JSebroskv Slent CCook DATE 4/19/18 3/29/18 4/19/18 OFFICE NRR/DLP/PBMB/BC NRR/DLP/PBMB/PM NAME EBowman JSebroskv DATE 5/1/18 5/3/18 UNITED STATES NUCLEAR REGULATORY COMMISSION WASHINGTON, D.C. 20555-0001 May 3, 2018 Vice President, Operations Entergy Nuclear Operations, Inc.
Palisades Nuclear Plant 27780 Blue Star Memorial Highway Covert, Ml 49043-9530
SUBJECT:
PALISADES NUCLEAR PLANT - CORRECTION LETTER FOR STAFF ASSESSMENTS ASSOCIATED WITH RESPONSE TO 10 CFR 50.54(f)
INFORMATION REQUEST - FLOOD-CAUSING MECHANISM REEVALUATION
Dear Sir or Madam:
The purpose of this letter is to provide corrections to two staff assessments the U.S. Nuclear Regulatory Commission (NRC) issued associated with an Entergy Nuclear Operations, Inc.
(Entergy, the licensee) letter dated March 11, 2015 (Agencywide Documents Access and Management System (ADAMS) Accession No. ML15114A209). Entergy's March 11, 2015, letter provided the response for Palisades Nuclear Plant (Palisades) to a March 12, 2012, NRC request for information that was issued under Title 10 of the Code of Federal Regulations, Section 50.54(f). The NRC staff assessments that are being corrected are dated December 23, 2015, and February 14, 2018 (ADAMS Accession Nos. ML15356A765 and ML18037A625, respectively).
Correction to Discussion of Palisades Current Design Basis Table 1 and Table 3.1-1 of the NRC staff's letters dated December 23, 2015, and February 14, 2018, respectively, state the following regarding storm surge:
Flood Mechanism Stillwater Elevations, feet Associated Effects, Current Design Basis (ft.) National Geodetic ft. (COB) Flood Vertical Datum of 1929 Elevation, ft.
(NGVD29) NGVD29 Storm Surge 594.1 8 602.1 In addition, Section 3.5 of the NRC staff's February 14, 2018, letter states the following regarding the Palisades COB:
The COB probable maximum flood elevation for storm surge is based on a stillwater-surface elevation of 594.1 ft. NGVD29, and an elevation of 602.1 ft.
NGVD 29 including wind waves and runup at the lakeward side of the circulation water pipes. The COB design wave height is 8-ft., producing a combined COB total water elevation of elevation 602.1 ft. NGVD29 along the lakeward side of the circulation water pipe.
The above descriptions are not an accurate reflection of the Palisades COB and the associated effects. As stated in Section 3.9.2.1. 7 of the licensee's March 11, 2015, flood hazard reevaluation report (FHRR), wave runup height is not measured as height above the stillwater
elevation but is instead measured from the ground elevation near the Screenhouse/lntake Structure.
Table 1 and Table 3.1-1 of the staff's assessment dated December 23, 2015, and February 14, 2018, respectively, are corrected as follows:
Stillwater Elevation, ft. National Geodetic Current Design Basis Vertical Datum of Associated (COB) Flood Elevation, ft.
Flood Mechanism 1929 (NGVD29} Effects, ft. NGVD29 Storm Surge at the g ~
Screen house/Intake 594.1 (See Note 1) 597.0 (See Note 1)
Structure Storm Surge at Not included ~
locations other than at 594.1 in the COB the Screenhouse/lntake (See Note 2) 594.1 Structure Note 1: The licensee's COB includes an evaluation of wave runup (associated effects) at the Screenhouse/lntake Structure. The wave runup is estimated as 8 ft. above the ground surface elevation at that location (elevation 589.0 ft. NGVD29). This results in a maximum COB elevation of 597.0 ft. NGVD29 at the Screenhouse/lntake Structure.
Note 2: The Screenhouse/lntake Structure was the focal point of the COB analysis for the storm surge flood-causing mechanism. Associated effects were only calculated at this structure. At other locations, the Palisades COB elevation for the storm surge flood-causing mechanism is equal to the stillwater elevation.
The staff also corrects Section 3.5 of the February 14, 2018, letter with the following replacement text:
The Palisades COB includes an evaluation of the dynamic effect of wave run-up to a height of 597.0 ft NGVD29 at the Screen House/Intake Structure, which is capable of withstanding the loads. The COB for Palisades evaluated the impact of stillwater storm surge flooding of 594.1 feet on the safety-related service water pumps. The licensee concluded that the service water pumps would be able to perform their intended safety-related function under these flooding conditions.
The staff notes that Table 2, and Table 4.1-1, of the staff's assessment letters dated December 23, 2015, and February 14, 2018, remain correct and are unchanged. These tables provide information regarding the reevaluated hazard elevations for flood-causing mechanisms not bounded by the Palisades COB and include the following information:
Flood Mechanism Stillwater Associated Reevaluated Hazard Elevations, ft. Effects, ft. Elevation, ft.
NGVD29 NGVD29 Storm Surge (H.4 Combined 593.9 8.3 602.2 Flood Event): Lakeward of Circulation Water Pipes Landward of Circulation Water 593.9 0.4 594.3 Pipes Landward of Turbine Buildinq 593.9 0.4 594.3 North of Turbine Buildinq 593.9 1.1 595.0 The licensee is expected to apply information contained in Table 2 and Table 4.1-1 associated with a storm surge flood-causing mechanism as part of their flooding mitigation strategies assessment, and the flooding focused evaluation or integrated assessment, as appropriate.
Correction to Table 3.2-1 of the Staff Assessment Dated February 14, 2018 Table 3.2-1 of the staff assessment dated February 14, 2018, is corrected as follows regarding Manhole #4:
ID Description Ground Maximum Maximum Time to Bounded (B) or Number Surface Flood Flood Maximum Not Bounded (NB)
Elevation, Elevation, Depth, ft. Flood ft. ft. Elevation NGVD29 NGVD29 (hours) 28 Manhole #4 623.9 626.1 2.2 M NB (East of 0.2 Containment Building)
The staff found the licensee estimate of the time to maximum flood elevation for this location to be reasonable. This duration is 0.2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br />, not 0.5 hours5.787037e-5 days <br />0.00139 hours <br />8.267196e-6 weeks <br />1.9025e-6 months <br /> as previously reported.
If you have any questions, please contact me at (301) 415-1132 or via e-mail at Joseph.Sebrosky@nrc.gov.
Sin~
seph M. Se rosky, Seni Pro* ct Manager yond-Desi n-Basis Management Branch ivision of Licensing Projects Office of Nuclear Reactor Regulation Docket No. 50-255 cc: Distribution via Listserv
ML18086A218 *via e-mail OFFICE NRR/DLP/PBMB/PM NRR/DLP/PBMB/LA NRO/DSENRHM/BC*
NAME JSebroskv Slent CCook DATE 4/19/18 3/29/18 4/19/18 OFFICE NRR/DLP/PBMB/BC NRR/DLP/PBMB/PM NAME EBowman JSebroskv DATE 5/1/18 5/3/18