ML110700622
| ML110700622 | |
| Person / Time | |
|---|---|
| Site: | Watts Bar  |
| Issue date: | 03/30/2011 |
| From: | Justin Poole Watts Bar Special Projects Branch |
| To: | Bhatnagar A Tennessee Valley Authority |
| Poole Justin/DORL/LPL3-1/ 301-415-2048 | |
| References | |
| TAC ME3945 | |
| Download: ML110700622 (4) | |
Text
UNITED STATES NUCLEAR REGULATORY COMMISSION WASHINGTON, D.C. 20555-0001 Narch 30, 2011 Mr. Ashok S. Bhatnagar Senior Vice President Nuclear Generation Development and Construction Tennessee Valley Authority 6A Lookout Place 1101 Market Street Chattanooga, TN 37402-2801
SUBJECT:
WATTS BAR NUCLEAR PLANT, UNIT 2 - REQUEST FOR ADDITIONAL INFORMATION REGARDING FINAL SAFETY ANALYSIS REPORT SECTION 2.4 (TAC NO. ME3945)
Dear Mr. Bhatnagar:
By letter dated May 7. 2010, the Tennessee Valley Authority (TVA) submitted Amendment 98 to the Final Safety Analysis Report (FSAR) for Watts Bar Nuclear Plant, Unit 2. In this regard, the U.S. Nuclear Regulatory Commission (NRC) staff has been reviewing FSAR Section 2.4, "Hydrologic Engineering." In a letter dated January 24,2011, TVA also provided anticipated changes to FSAR Section 2.4 in advance of FSAR Amendment 103, to facilitate the continuing review by the NRC staff.
The NRC staff has reviewed the information provided by TVA in FSAR Amendment 98 and in the January 24, 2011, letter, and finds that additional information is needed to continue its review of FSAR Section 2.4. The specific questions are in the enclosed request for additional information.
A response is required within 15 days of receipt of this letter.
If you should have any questions, please contact me at 301-415-2048.
Sincerely,
?£tSJ),~ f.
Justin C. Poole, Project Manager Watts Bar Special Projects Branch Division of Operating Reactor licensing Office of Nuclear Reactor Regulation Docket No. 50-391
Enclosure:
Request for Additional Information cc w/encl: Distribution via listserv
REQUEST FOR ADDITIONAL INFORMATION WATTS BAR NUCLEAR PLANT, UNIT 2 FINAL SAFETY ANALYSIS REPORT SECTION 2.4 TENNESSEE VALLEY AUTHORITY DOCKET NO. 50-391 By letter dated May 7,2010, Tennessee Valley Authority (TVA) provided Amendment 98 to the Watts Bar Nuclear Plant (WBN), Unit 2, Final Safety Analysis Report (FSAR). In Amendment 98, TVA included information in Section 2.4, "Hydrologic Engineering." In a letter dated January 24,2011, TVA also provided anticipated changes to FSAR Section 2.4 in advance of FSAR Amendment 103, to facilitate the continuing review by the Nuclear Regulatory Commission (NRC) staff. In the discussion in FSAR Subsection 2.4.3 regarding probable maximum flood (PMF) on streams and rivers, the staff finds that TVA makes no mention that the predicted PMF level is dependent on temporary modifications currently in place where sand baskets about 4 feet in height are deployed in the vicinity of four dams (Fort Loudoun, Tellico, Cherokee, and Watts Bar). Thus, the NRC staff requests the following additional information in order to continue its review:
- 1.
How does WBN Unit 2 licensing bases credit the use of the sand baskets with regards to protecting Unit 2?
- 2.
During the meeting between TVA and the NRC on July 2,2010, to discuss hydrology concerns expressed by the staff related to the operating TVA units, TVA indicated that the Cherokee and Douglas dams require rigorous evaluation in the form of finite element analyses to confirm their structural adequacy and functionality for long-term operation.
The NRC staff agreed with TVA's action as a confirmation of its earlier operability determination for PMF related to the operating units. TVA also indicated that the estimated completion of such analyses will likely extend beyond the projected start of operation for WBN Unit 2. Discuss how the short-term operability and the long-term functionality of these dams are reflected in the licensing bases for WBN Unit 2.
- 3.
Discuss the basis for concluding the structural adequacy of the sand baskets under either scenario of temporary or long-term deployment. Specifically, address the ability of the sand baskets to withstand debris, erosion and impact loading caused by tornado, hurricane, or large moving objects such as trucks.
- 4.
Clarify whether the sand baskets will be replaced or modified as permanent structures at some point in the future, after WBN Unit 2 receives its operating license. When does TVA expect to perform such replacement or modification? If the sand baskets will be made permanent, provide documentation of long-term usage either from the manufacturer, equivalent projects, or other appropriate supporting documentation. The documentation should include references to maintenance and operation plans of the systems, or replacement plans to achieve a long-term solution.
Enclosure
- 2
- 5.
Identify all incidents of current operability determinations TVA made related to WBN Unit 1, that are relevant to Unit 2, where the licensing bases for Unit 1 regarding hydrology and probable maximum flood level were not fully met. Discuss how TVA intends to address in the licensing basis for Unit 2, each incident where TVA relied on an operability determination for continued operation at Unit 1 until full compliance with the licensing basis is reached.
March ~\\(), /011 Mr. Ashok S. Bhatnagar Senior Vice President Nuclear Generation Development and Construction Tennessee Valley Authority 6A Lookout Place 1101 Market Street Chattanooga, TN 37402-2801
SUBJECT:
WATTS BAR NUCLEAR PLANT, UNIT 2 - REQUEST FOR ADDITIONAL INFORMATION REGARDING FINAL SAFETY ANALYSIS REPORT SECTION 2.4 (TAC NO. ME3945)
Dear Mr. Bhatnagar:
By letter dated May 7,2010, the Tennessee Valley Authority (TVA) submitted Amendment 98 to the Final Safety Analysis Report (FSAR) for Watts Bar Nuclear Plant, Unit 2. In this regard, the U.S. Nuclear Regulatory Commission (NRC) staff has been reviewing FSAR Section 2.4, "Hydrologic Engineering." In a letter dated January 24, 2011, TVA also provided anticipated changes to FSAR Section 2.4 in advance of FSAR Amendment 103, to facilitate the continuing review by the NRC staff.
The NRC staff has reviewed the information provided by TVA in FSAR Amendment 98 and in the January 24, 2011, letter, and finds that additional information is needed to continue its review of FSAR Section 2.4. The specific questions are in the enclosed request for additional information.
A response is required within 15 days of receipt of this letter.
If you should have any questions, please contact me at 301-415-2048.
Sincerely, IRAJ Justin C. Poole, Project Manager Watts Bar Special Projects Branch Division of Operating Reactor licensing Office of Nuclear Reactor Regulation Docket No. 50-391
Enclosure:
Request for Additional Information cc w/encl: Distribution via Listserv DISTRIBUTION:
RidsOgcRp Resource PUBLIC RidsNrrDorlLpwb Resource LPWB Reading File RidsNrrLABClayton Resource RidsAcrsAcnw_MailCTR Resource RidsNrrDorlDpr RidsRgn2MailCenter Resource RidsNrrDeEmcb Resource RidsNrrPMWattsBar2 Resource KManoly, NRR ADAMS Accession No. ML110700622 OFFICE LPWB/PM LPWB/LA EMCB/BC OGC
- NLO LPWB/BC NAME JPoole BClayton MKhanna DRoth SCampbeli DATE 03/11/11 03/11/11 03/11/11 03/14/11 03/30/11 OFFICIAL AGENCY RECORD