ML11167A061

OL - FW: 6-01-11_WBN U2 FSAR 2 4 Mtg Info to Nrc_Letter Only

ML11167A061
Person / Time
Site:	Watts Bar
Issue date:	06/03/2011
From:	Office of Nuclear Reactor Regulation
To:	Division of Operating Reactor Licensing
References
Download: ML11167A061 (8)

Text

WBN2Public Resource From: Poole, Justin Sent: Friday, June 03, 2011 7:46 AM To: Hoang, Dan Cc: WBN2HearingFile Resource

Subject:

FW: 6-01-11_WBN U2 FSAR 2 4 Mtg Info to NRC_Letter only Attachments: image001.jpg; 6-01-11_WBN U2 FSAR 2 4 Mtg Info to NRC_Letter only.pdf Here is a copy of the letter TVA sent to document control yesterday. I believe you have a copy of enclosure one which was the slide presentation they did for you on your trip. Enclosures 2 and 3 containing the calcs were too big to include via email so they will arrive with the official submittal, probably on Monday.

Justin C. Poole Project Manager NRR/DORL/LPWB U.S. Nuclear Regulatory Commission (301)4152048 email: Justin.Poole@nrc.gov From: Hamill, Carol L [1]

Sent: Thursday, June 02, 2011 9:58 AM To: Epperson, Dan; Poole, Justin; Raghavan, Rags; Milano, Patrick; Campbell, Stephen

Subject:

6-01-11_WBN U2 FSAR 2 4 Mtg Info to NRC_Letter only Please see attached letter that was sent to the NRC today. was too large to include with this letter, so I will send a followup e-mail with Enclosure 1 only. For those receiving hard copies in the mail, Enclosure 1 will be mailed with the letter.

Please let me know if you have any questions.

Carol L. Hamill Licensing/Quality Assurance WBN Unit 2 Project, EQB 1B WBN 4233653177 4233653833 clhamill@tva.gov 1

Hearing Identifier: Watts_Bar_2_Operating_LA_Public Email Number: 400 Mail Envelope Properties (19D990B45D535548840D1118C451C74D886EB31BF0)

Subject:

FW: 6-01-11_WBN U2 FSAR 2 4 Mtg Info to NRC_Letter only Sent Date: 6/3/2011 7:45:45 AM Received Date: 6/3/2011 7:45:46 AM From: Poole, Justin Created By: Justin.Poole@nrc.gov Recipients:

"WBN2HearingFile Resource" <WBN2HearingFile.Resource@nrc.gov>

Tracking Status: None "Hoang, Dan" <Dan.Hoang@nrc.gov>

Tracking Status: None Post Office: HQCLSTR02.nrc.gov Files Size Date & Time MESSAGE 1220 6/3/2011 7:45:46 AM image001.jpg 1023 6-01-11_WBN U2 FSAR 2 4 Mtg Info to NRC_Letter only.pdf 325922 Options Priority: Standard Return Notification: No Reply Requested: No Sensitivity: Normal Expiration Date:

Recipients Received:

Page 1 of 1 file://c:\EMailCapture\Watts_Bar_2_Operating_LA_Public\400\attch1.jpg 6/16/2011

U.S. Nuclear Regulatory Commission Page 2 June 1, 2011

Enclosures:

1. Presentation Package, Temporary Dams Modification Project

2. Calculation RSOFLHROGCDX00033320090003, PMF Temporary Modification Analysis

3. Calculation RSOGENROGCDX00033320110002, Seismic Evaluation of HESCO Baskets

4. Summary of Problem Evaluation Report 154477 cc (w/Enclosures 1 & 4 only):

U. S. Nuclear Regulatory Commission Region II Marquis One Tower 245 Peachtree Center Ave., NE Suite 1200 Atlanta, Georgia 30303-1257 Mr. Dan Hoang (w/Enclosures 1, 2, 3, and 4)

U.S. Nuclear Regulatory Commission O-09D3 11555 Rockville Pike Rockville, MD 20852-2738 NRC Resident Inspector Unit 2 Watts Bar Nuclear Plant 1260 Nuclear Plant Road Spring City, TN 37381

U.S. Nuclear Regulatory Commission Page 3 June 1, 2011 bcc (w/Enclosures 1 & 4 only):

Stephen Campbell U.S. Nuclear Regulatory Commission MS 08H4A One White Flint North 11555 Rockville Pike Rockville, MD 20852-2738 Charles Casto, Deputy Regional Administrator for Construction U.S. Nuclear Regulatory Commission Region II Marquis One Tower 245 Peachtree Center Ave., N.E., Suite 1200 Atlanta, GA 30303-1257

ENCLOSURE 1 PRESENTATION PACKAGE TEMPORARY DAMS MODIFICATION PROJECT

ENCLOSURE 4

SUMMARY

OF PROBLEM EVALUATION REPORT 154477 The hydrology issues at Watts Bar Nuclear Plant are being tracked through a single Problem Evaluation Report (PER), PER 154477. PER 154477 was initially written to address the assumptions made on Tellico Dam with respect to stability during the Operating Basis Earthquake. As other issues were identified during the hydrology analysis input reconstitution, additional PERs were written to address the specific issue and to address operability and functionality of that issue. As these additional PERs were closed, they were added to PER 154477 as the single tracking document. Currently, the open corrective actions remaining for PER 154477 are for documentation corrections.

Upon completion of the hydrology analysis for probable maximum flood (PMF), one of the additional PERs, PER 211722, was written to address the higher than original licensed PMF level (0.7 feet increase). Equipment required for flood mode was evaluated for impact of the increased PMF level. The review concluded that all equipment was adequate for the PMF event with margin except for the Unit 1 Thermal Barrier Booster (TBB) Pump motors. The base of these motors is located within 1/4 of the revised design basis flood level inside the structures.

The Unit 2 pumps are at the same elevation as the Unit 1 pumps. Since these components have reduced margin, a Unit 1 temporary alteration control measure was implemented to provide protection around the equipment through the use of a barrier. This protection is implemented as part of the flood mode preparations as described in Abnormal Operating procedures. The barrier is not required to deem the pump motors functional but is recommended to provide assurance of additional margin. Unit 2 is implementing a permanent design change to protect the pump motors.

To date, the only issue identified in the additional PERs is protection of the TBB pump motors as described above.