ML14030A419
| ML14030A419 | |
| Person / Time | |
|---|---|
| Site: | Harris  |
| Issue date: | 02/10/2014 |
| From: | Andrew Hon Plant Licensing Branch II |
| To: | Kapopoulos E Duke Energy Progress |
| Hon A NRR/DORL/LPL2-2 | |
| References | |
| TAC MF1103 | |
| Download: ML14030A419 (8) | |
Text
UNITED STATES NUCLEAR REGULATORY COMMISSION WASHINGTON, D.C. 20555-0001 Mr. Ernest J. Kapopoulos Site Vice President Duke Energy Progress, Inc.
Shearon Harris Nuclear Power Plant 5413 Shearon Harris Road New Hill, NC 27562-0165 February 10, 2014
SUBJECT:
SHEARON HARRIS NUCLEAR POWER PLANT, UNIT 1 - REQUEST FOR ADDITIONAL INFORMATION REGARDING FUKUSHIMA LESSONS LEARNED
-FLOODING HAZARD REANALYSIS REPORT (TAC NO. MF1103)
Dear Mr. Kapopoulos:
By letter dated March 12, 2012, the U.S. Nuclear Regulatory Commission (NRC) issued a request for information pursuant to Title 10 of the Code of Federal Regulations, Section 50. 54(f)
(hereafter referred to as the 50.54(f) letter). The request was issued as a part of implementing lessons-learned from the accident at the Fukushima Dai-ichi nuclear power plant. Enclosure 2 to the 50.54(f) letter requested licensees to perform a flood hazard re-evaluation using present-day methodologies and guidance.
By letter dated March 12, 2013, Duke Energy submitted a response to Enclosure 2, Required Response 2 of the 50.54(f) letter. The NRC staff has determined that additional information is needed to complete its review.
This request was discussed with Mr. Bryan Miller of your staff on January 28, 2014. The NRC staff's determination was confirmed that the proposed request for additional information (RAI) does not contain sensitive information that should be withheld from the public. Furthermore.
you would provide a complete response to the RAI by March 24, 2014.
If you have any questions, please contact me at 301-415-8480 or via e-mail at Andrew.Hon@ nrc.gov.
Docket Nos. 50-400
Enclosure:
Request for Additional Information cc w/encl: Distribution via Listserv Sincerely, Andrew Hon Plant Licensing Branch 11-2 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation
REQUEST FOR ADDITIONAL INFORMATION FUKUSHIMA LESSONS LEARNED FLOODING HAZARD REEVALUATION REPORT DUKE ENERGY PROGRESS, INC.
SHEARON HARRIS NUCLEAR POWER PLANT (HNP), UNIT 1 DOCKET NOS. 50-400 By letter dated March 12, 2012, the U.S. Nuclear Regulatory Commission (NRC) issued a request for information pursuant to Title 10 of the Code of Federal Regulations, Section 50.54(f)
(hereafter referred to as the 50.54(f) letter). The request was issued as a part of implementing lessons-learned from the accident at the Fukushima Dai-ichi nuclear power plant. Enclosure 2 to the 50.54(f) letter requested licensees to perform a flood hazard reevaluation using present-day methodologies and guidance.
By letter dated March 12, 2013 (Agencywide Documents Access and Management System (ADAMS) Accession No. ML13079A253), Duke Energy submitted a response to Enclosure 2, Required Response 2 of the 50.54(f) letter. The NRC staff has determined that the following additional information is needed to complete its review.
RAI No. 1, Local Intense Precipitation Flooding -A
Background:
Given the significant role of elevation data in defining slopes and flowpaths, the staff needs a description of the methods used to incorporate elevation measurements into its local intense precipitation-induced flood analyses, in order to complete the staff's independent evaluations.
Request: Provide descriptions of the sources of elevation data, the methods used to incorporate elevation measurements into local intense precipitation flood analysis, and the likely magnitude of the errors associated with these elevations.
RAI No.2. Local Intense Precipitation Flooding-B
Background:
Given the significant role of estimated times-of-concentration in the determination of the rainfall intensity and therefore the estimation of discharge during the local intense precipitation event, the staff needs the data used to estimate times-of-concentrations for all subbasins, in order to complete the staff's independent evaluations.
Request: Provide the data used to estimate times-of-concentration for each subbasin.
RAI No. 3, Local Intense Precipitation Flooding - C
Background:
Given the significant role of depressions in Subbasins 5, 6, 8, and 16 in the estimation of overall discharge conveyed downstream, the staff needs more detailed description of these areas and why these depressions would remain unchanged in future, in order to complete the staff's independent evaluations.
Enclosure Request: Provide detailed description of the areas with depressions in Subbasins 5, 6, 8, and 16 and why these depressions would remain unchanged in future.
RAI No. 4, Local Intense Precipitation Flooding - D
Background:
Given the significant role of the HEC-RAS model in the licensee's analysis and the need to review the formulation of its complex spatially and temporally distributed input, the staff needs the licensee's HEC-RAS input files used for local intense precipitation analysis, in order to complete the staff's independent evaluations.
Request: Provide electronic versions of the input files used for HEC-RAS analysis in the flooding hazard reanalysis report (FHRR) related to local intense precipitation analyses. Also, provide a list or map showing which flowpath reaches used in the HEC-RAS model simulation are located in gravel-covered areas and which are located in concrete or asphalt-covered areas.
RAI No. 5, Local Intense Precipitation Flooding - E
Background:
The staff noted that mean sea level (MSL) and National Geodetic Vertical Datum of 1929 (NGVD29) datums are used in the FHRR such that they appear interchangeable. However, the FHRR does not clearly state if this is the case. Given the significant role the elevation data have in relating water-surface elevations and site topography through the use of consistent datums, the staff needs a consistent description of the relationship between MSL and NGVD29 used in its analysis, in order to complete the staff's independent evaluations.
Request: Clarify the relationship between the vertical elevation datums used in the FHRR.
RAI No. 6, Local Intense Precipitation Flooding - F
Background:
In its review of the FHRR, the staff noted that the licensee did not provide full citations of technical references used in the local intense precipitation analysis. A full citation to the HNP Unit 1 Final Safety Analysis Report {FSAR) is also missing.
Request: Provide full citations to technical references and the HNP Unit 1 FSAR used in the FHRR.
RAI No.7, Streams and Rivers Flooding-A
Background:
The licensee used the analyses from the combined license application (COLA) for the proposed Harris Advance Reactor (HAR) Units 2 and 3 (Duke 2013) as the basis for reevaluating flooding from streams and rivers at the current HNP Unit 1 site. The COLA was based on a Main Dam configuration different from that used for developing the current licensing basis (CLB) (Duke 2013). In addition to the FHRR and HNP FSAR, NRC staff used the latest revision (Rev. 4) of the HAR COLA (Progress Energy 2012) for its review.
Request: Provide an explanation why the HAR Units 2 and 3 COLA analyses are appropriate for the reanalysis of HNP CLB for flooding from streams and rivers.
RAJ No. 8. Streams and Rivers Flooding - B
Background:
Same as RAI No. 7 Request: Provide an explanation of changes to the COLA analyses to correspond to the site and reservoir configurations with only HNP Unit 1 present.
RAI No. 9, Streams and Rivers Flooding - C
Background:
The licensee determined that a 259 km2 (1 00 mi2) isohyetal pattern maximized the precipitation depth over the Buckhorn Creek watershed. Staff were unable to find a figure illustrating the distribution of the Probable Maximum Precipitation (PMP) pattern from U.S.
Weather Bureau Hydro-meteorological Report (HMR 52) over the Buckhorn Creek watershed.
Request: Provide a figure showing the distribution of the PMP pattern derived from HMR 52 over the Buckhorn Creek watershed.
RAI No. 10. Streams and Rivers Flooding - E
Background:
Infiltration rates were estimated by the licensee to be in a range of 0.13 to 0.38 mm/hr (0.05 to 0.15 in./hr), with the larger value used as the initial infiltration rate. While the staff found that the infiltration calculation methods are appropriate, the conservatism of the infiltration rates needs to be demonstrated.
Request: Provide an explanation of how an initial infiltration rate of 0.38 mm/hr (0.15 in./hr) is conservative for a range of estimated infiltration rates of 0.13 to 0.38 mm/hr (0. 05 to 0.15 in./hr) for the predominant soil type.
RAI No. 11, Streams and Rivers Flooding - F
Background:
The geometric characteristics of the residual area (i.e., the land area that drains directly to the reservoirs) were presumably based on distances to the reservoir, though the method for developing them is not described by the licensee.
Request: Provide an explanation of the method used for hydrograph development of the residual area around the Main and Auxiliary Reservoirs.
RAI No. 12. Streams and Rivers Flooding - G
Background:
The licensee also states that the Auxiliary Dam spillway rating curve was taken from the HAR COLA (Progress Energy 2012); however, it is unclear whether the Auxiliary Dam spillway rating curve includes tailwater effects from discharge to the Main Reservoir.
Request: Provide an explanation of the effects of tailwater effects from Auxiliary Dam spillway discharges to the Main Reservoir and how they were incorporated into the rating curve of the Auxiliary Dam.
RAI No. 13, Streams and Rivers Flooding - H
Background:
The licensee states that the primary discharge coefficient values from the HAR COLA are 3.95 and 3.92 for the Main Dam and the Auxiliary Dam, respectively. The licensee did a curve fit to the rating curve from HNP FSAR Figure 2.4.3-3 (PEC 2009) using a coefficient of 3.95 but it did not provide an adequate fit. By back calculation to the HNP rating curve, the licensee computed a primary discharge coefficient of 3.5.
Request: Provide an explanation for the discrepancy between the two discharge rating curve coefficients for the Main Dam spillway.
RAI No. 14, Streams and Rivers Flooding-H
Background:
The licensee also used HEC-HMS to compute the probable maximum flood (PMF) water surface elevations in the Main and Auxiliary Reservoirs using level-pool routing of runoff along with the reservoir stage-storage and storage-discharge curves.
Request: Provide an explanation of the conservatism in using level-pool routing as opposed to hydraulic routing for the PMF elevation computations in the Main and Auxiliary Reservoirs.
RAI No. 15, Streams and Rivers Flooding - I
Background:
Staff examined the stage capacity curve for the Main Reservoir (HNP FSAR Figure 2.4.3-6; PEC 2009) and found that it only extends up to an elevation of 76.2 m (250 ft).
Staff could not find a figure or table corresponding to the extension of the Main Dam spillway rating curve.
Request: Clarify if the reservoir capacity curve was extended to 79.2 m (260ft) as done for the spillway discharge rating curve. If the capacity curve was not extended, provide an explanation of the method used to handle level-pool routing if the stage exceeded 76.2 m (250 ft).
RAI No. 16, Streams and Rivers Flooding-J
Background:
In its review of the FHRR, the staff noted that the licensee did not provide full citations of technical references used in the flooding analysis for streams and rivers. A full citation to the HNP Unit 1 FSAR and the HAR Units 2 and 3 COLA are also missing.
Request: Provide full citations to technical references, to the HNP Unit 1 FSAR, and to the HAR Units 2 and 3 COLA used in the FHRR.
RAI No. 17, Storm Surge Flooding
Background:
In its review of the FHRR, the staff noted that the licensee cited the Nuclear Energy lnstitude (NEI) white paper Post-Fukushima Near-Term Task Force Recommendation 2.1, Supplemental Guidance for the Evaluation of Dam Failures, Rev. B, for the estimation of maximum wave run-up.
Request: Explain how the use of the NEI white paper fulfills the requirement specified in the March 12, 2012 50.54(f) letter to use current applicable Commission requirements and guidance in performing the flood hazard re-evaluation of storm surge.
RAI No. 18, Hazard Input for the Integrated Assessment-A Backgroun d: The March 12, 2012, 50.54(f) letter, Enclosure 2, requests the licensee to perform an integrated assessment of the plant's response to the re-evaluated hazard if the re-evaluated flood hazard is not bounded by the current design basis.
Request: The licensee is requested to provide the applicable flood event duration parameters (see definition and Figure 6 of the Guidance for Performing an Integrated Assessment, JLD-SG-2012-05) associated with mechanisms that trigger an Integrated Assessment. This includes (as applicable) the warning time the site will have to prepare for the event, the period of time the site is inundated, and the period of time necessary for water to recede off the site for the mechanisms that are not bounded by the current design basis. The licensee is also requested to provide a basis for the flood event duration parameters. The basis for warning time may include information from relevant forecasting methods (e.g., products from local, regional, or national weather forecasting centers).
RAI No. 19, Hazard Input for the Integrated Assessment - 8
Background:
The March 12, 2012, 50.54(f) letter, Enclosure 2, requests the licensee to perform an integrated assessment of the plant's response to the re-evaluated hazard if the re-evaluated flood hazard is not bounded by the current design basis.
Request: Provide the flood height and associated effects (as defined in Section 9 of JLD-ISG-2012-05) that are not described in the flood hazard re-evaluation report for mechanisms that trigger an Integrated Assessment. This includes the following quantified information for each mechanism (as applicable):
Hydrodynamic loading, including debris, Effects caused by sediment deposition and erosion (e.g., flow velocities, scour),
Concurrent site conditions, including adverse weather, and Groundwater ingress.
If you have any questions, please contact me at 301-415-8480 or via e-mail at Andrew. Hon@nrc.gov.
Docket Nos. 50-400
Enclosure:
Request for Additional Information cc w/encl: Distribution via Listserv DISTRIBUTION:
PUBLIC LPL2-2 Reading RidsAcrsAcnw_MaiiCTR Resource RidsNroDsea Resource RidsNrrDorllpl2-2 Resource RidsNrrLABCiayton Resource RidsNrrPMHarris Resource RidsRgn2MaiiCenter Resource CCook, NRO EMiller, NRR/DORL ADAMS A ccess1on N o.: ML14030A419 Sincerely,
/RAJ Andrew Hon Plant Licensing Branch 11-2 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation
- 1 d t d J v1a e-ma1 ae anuary 20 2014 I
OFFICE NRR/DORLILPL2-2/PM NRR/DORLILPL2-2/LA NRO/DSENRHMB* NRR!DORLILPL2-2/BC NRRIDORL/LPL2-2/PM NAME AHon BCiayton CCook JQuichocho (FSaba for) AHon DATE 2/6/14 2/6/14 01/20/14 2/10/14 2/10/14 OFFICIAL RECORD COPY