ML12363A102
| ML12363A102 | |
| Person / Time | |
|---|---|
| Site: | South Texas  |
| Issue date: | 12/19/2012 |
| From: | Gerry Powell South Texas |
| To: | Document Control Desk, Office of Nuclear Reactor Regulation |
| References | |
| NOC-AE-12002942, TAC ME4936, TAC ME4937 | |
| Download: ML12363A102 (7) | |
Text
Nuclear Operating Company South Texas Pro/ect Electric Generating Station PO. Box289 Wadsworth, Texas 77483 December 19, 2012 NOC-AE-1 2002942 10 CFR 54 STI: 33638751 File: G25 U. S. Nuclear Regulatory Commission Attention: Document Control Desk Washington, DC 20555-0001 South Texas Project Units 1 and 2 Docket Nos. STN 50-498, STN 50-499 Supplement 1 to Request for NRC Staff to Suspend Safety Review of South Texas Project License Renewal Application (TAC Nos. ME4936 and ME4937)
References:
- 1. STPNOC letter dated December 11, 2012, from D. W. Rencurrel to NRC Document Control Desk, "Request for NRC Staff to Suspend Safety Review of the South Texas Project License Renewal Application (TAC Nos. ME4936 and ME4937)" (NOC-AE-12002937)
- 2. NRC letter dated October 3, 2012, "Requests for Additional Information for the Review of the South Texas Project, Units 1 and 2, License Renewal Application - RWST Cracking, Set 24 (TAC Nos. ME4936 and ME4937)"(ML12256B049)
- 3. NRC letter dated November 19, 2012, "Requests for Additional Information for the Review of the South Texas Project, Units 1 and 2, License Renewal Application - Set 25 (TAC Nos. ME4936 and ME4937)"(ML12311A438)
- 4. STPNOC letter dated December 6, 2012, from D. W. Rencurrel to NRC Document Control Desk, "Partial Response to Requests for Additional Information for the Review of the South Texas Project, Units 1 and 2, License Renewal Application - Set 25 (TAC Nos. ME4936 and ME4937)"
By Reference 1, STP Nuclear Operating Company (STPNOC) requested a temporary suspension of the safety review of the South Texas Project, Units 1 and 2, license renewal application. This letter addresses NRC requests for additional information provided in References 2 and 3. In addition, this letter addresses the implementation of commitments associated with the License Renewal Application that will be deferred until after the resumption of review activities.
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NOC-AE-12002942 Page 2 Reference 4 provided a response to RAI A1-2, "Follow-up on Operating Experience Implementation." RAI 1-2 was part of the information requested by Reference 3 - Set 25.
A response to the requested information in Reference 2 and the remaining requested information in Reference 3 will be provided by February 28, 2014.
The Enclosure to this letter provides a revision to the implementation of commitments impacted by the temporary suspension of the safety review. The changes are depicted in a line-in/line-out format. There are no other regulatory commitments in this letter.
Should you have any questions regarding this letter, please contact either Arden Aldridge, STP License Renewal Project Lead, at (361) 972-8243 or Ken Taplett, STP License Renewal Project regulatory point-of-contact, at (361) 972-8416.
G. T. Powell Vice President, Generation KJT
Enclosure:
License Renewal Commitments
NOC-AE-12002942 Page 3 cc:
(paper copy)
(electronic copy)
Regional Administrator, Region IV U. S. Nuclear Regulatory Commission 1600 East Lamar Boulevard Arlington, Texas 76011-4511 Balwant K. Singal Senior Project Manager U.S. Nuclear Regulatory Commission One White Flint North (MS 8B1) 11555 Rockville Pike Rockville, MD 20852 Senior Resident Inspector U. S. Nuclear Regulatory Commission P. 0. Box 289, Mail Code: MN1 16 Wadsworth, TX 77483 C. M. Canady City of Austin Electric Utility Department 721 Barton Springs Road Austin, TX 78704 John W. Daily License Renewal Project Manager (Safety)
U.S. Nuclear Regulatory Commission One White Flint North (MS 011-F1)
Washington, DC 20555-0001 Tam Tran License Renewal Project Manager (Environmental)
U. S. Nuclear Regulatory Commission One White Flint North (MS 011 F01)
Washington, DC 20555-0001 A. H. Gutterman, Esquire Kathryn M. Sutton, Esquire Morgan, Lewis & Bockius, LLP John Ragan Chris O'Hara Jim von Suskil NRG South Texas LP Kevin Polio Richard Pena City Public Service Peter Nemeth Crain Caton & James, P.C.
C. Mele City of Austin Richard A. Ratliff Alice Rogers Texas Department of State Health Services Balwant K. Singal John W. Daily Tam Tran U. S. Nuclear Regulatory Commission
Enclosure NOC-AE-12002942 Page 1 of 4 A4 LICENSE RENEWAL COMMITMENTS Table A4-1 identifies proposed actions committed to by STPNOC for STP Units 1 and 2 in its License Renewal Application. These and other actions are proposed regulatory commitments. This list will be revised, as necessary, in subsequent amendments to reflect changes resulting from *IRC questions and STPNOC responses. STPNOC will utilize the STP commitment tracking system to track regulatory commitments. The Condition Report (CR) number in the Implementation Schedule column of the table is for STPNOC tracking purposes and is not part of the amended LRA.
Table A4-1 License Renewal Commitments It #Commitment LRA Implementation Section ~
Schedule 4
Enhance the Open-Cycle Cooling Water System program procedures to:
B2.1.9 Prior to the period of include visual inspection of the strainer inlet area and the interior surfaces of the extended operation adjacent upstream and downstream piping. Material wastage, dimensional change, discoloration, and discontinuities in surface texture will be identified. These inspections CR 10-23256 will provide visual evidence of loss of material and fouling in the ECW system and serve as an indicator of the condition of the interior of ECW system piping components otherwise inaccessible for visual inspection.
include the acceptance criteria for this visual inspection.
require a minimum of 25 ECW piping locations be measured for wall thickness prior to the period of extended operation. Selected areas will include locations considered to have the highest corrosion rates, such as areas with stagnant flow.
require an engineering evaluation after each inspection of the aluminum-bronze piping inserted inside the slip-on flange downstream of the CCW heat exchanger, o
require the engineering evaluation calculated wear over the next inspection interval using a margin of four years of wear at the actual yearly wear rate, o
require corrective action in accordance with the corrective action program be initiated if the calculated wear indicates that the aluminum-bronze piping wall will reduce to a thickness of less than minimum wall thickness plus margin (four years of wear at the actual yearly wear rate),
Enclosure NOC-AE-12002942 Page 2 of 4 Table A4-1 License Renewal Commitments
" require loss of material in piping and protective coating failures be documented in the corrective action program, and require an engineering evaluation be performed when loss of material in piping or protective coating failures is identified.
Enhance the Open-Cycle Cooling Water System program procedures to:
visually inspect every six years, and test after 12 years of service at a six year frequency the coating applied on the essential chiller water box covers, standby diesel generator (SDG) jacket water coolers, SDG lube oil coolers, SDG intercoolers and interconnection piping. The coating test performed are low voltage holiday test per ASTM D5162, dry film thickness test per ASTM D7091 and Steel Structures Painting Council (SSPC) PA-2 and pull off adhesion test per ASTM D4541, require coating inspections and tests be performed by a qualified Nuclear Coating Specialist (NCS) as defined by ASTM D7108 or by Coatings Surveillance Personnel (CSP) under the technical direction of the NCS.
Prior to the ncxt Fchedulad in8Pecti9n February 28. 2014 44 Structural integrity analyses will be updated and testing will be conducted to confirm that methodologies and assumptions based on past information remain valid.
o Six samples from three aluminum bronze components recently removed from service will be tested.
The samples will be tested for chemical composition including aluminum content, mechanical properties (such as fracture toughness, yield and ultimate tensile strengths) and microstructure.
- The acceptance criterion for ultimate tensile strength value of aluminum bronze material is greater than or equal to 30 ksi. The acceptance criterion for fracture toughness is 65 ksi in1/2 for aluminum bronze castings and at welded joints in the heat affected zones. The acceptance criterion for yield strength is equal to or greater than one-half of the ultimate strength.
- Trend ultimate tensile strength and compare to the acceptance criterion.
B2.1.37 P~GF tG jaR~aF February 28, 2014 CR 12-22150
Enclosure NOC-AE-12002942 Page 3 of 4 Table A4-1 License Renewal Commitments Determine degree of dealloying and presence of cracks by destructive examination. Trend the degree of dealloying and cracking by comparing examination results with previous examination results.
The structural integrity analyses will be updated, as required.
The results of the testing and any required changes to the structural integrity analyses will be completed and sent to the NRC staff for review.
45 Enhance the Selective Leaching of Aluminum Bronze procedures to:
Volumetrically examine aluminum bronze material components in the ECW system that demonstrate external leakage where the configuration supports this type of examination,
" Destructively examine each aluminum bronze material component in the ECW system that demonstrates external leakage for the presence or absence of internal cracks and for the degree of dealloying. Profiling will continue until 10 percent of susceptible components are examined to validate the input parameters to the structural integrity analyses.
o Trend the degree of dealloying and cracking by comparing examination results with previous examination results.
Metallurgically test aluminum bronze material components in the ECW system that demonstrate external leakage until the following population of components is tested:
o At least three different size components of two samples each are tested, and o
At least nine total samples-are tested.
o Perform fracture toughness testing of test samples that include a crack in the dealloyed material where sufficient sample size supports bend testing.
o Trend ultimate tensile strength and compare to the acceptance criterion.
o Test samples for chemical composition including aluminum content, mechanical properties (such as yield and ultimate tensile strengths) and microstructure.
o Determine the degree of dealloying by destructive examination.
o Trend the degree of dealloying and cracking by comparing examination results with previous examination results.
" The acceptance criterion for ultimate tensile strenath value of aluminum bronze material is B2.1.37 March 31, 2013 February 28, 2014 CR 12-26987
Enclosure NOC-AE-12002942 Page 4 of 4 Table A4-1 License Renewal Commitments greater than or equal to 30 ksi. The acceptance criterion for fracture toughness is 65 ksi in1/ 2 for aluminum bronze castings and at welded joints in the heat affected zones. The acceptance criterion for yield strength is equal to or greater than one-half of the ultimate strength.
Perform an engineering evaluation at the end of each test to determine if the sample size requires adjustment based on the results of the tests.
Update the structural integrity analyses as required to validate adequate load carrying car~ccitv_
46 Leak rates that could occur upstream of any individual component supplied by the ECW system N/A
,M3rch 31, 2013 will be determined to validate the maximum size flaw for which piping can still perform its intended function.
February 28, 2014
- A summary of the results of these leak rates will be provided to the NRC for review.
'CR 12-27257