ML16103A512
| ML16103A512 | |
| Person / Time | |
|---|---|
| Site: | South Texas  |
| Issue date: | 02/24/2016 |
| From: | Dunn R F South Texas |
| To: | Document Control Desk, Office of Nuclear Reactor Regulation |
| References | |
| NOC-AE-16003341, STI: 34283123 | |
| Download: ML16103A512 (2) | |
Text
South Teras Project Electric Genemting Station P.O. Ba.-289 1-'hdsworth.
Texas 77./83 U. S. Nuclear Regulatory Commission Attention:
Document Control Desk Washington, D.C. 20555-0001 South Texas Project Unit 1 February 24, 2016 NOC-AE-16003341 10 CFR 50.46 (a)(3)(ii)
Docket No. STN 50-498 1 O CFR 50.46 Thirty-Day Report of Significant ECCS Model Changes
References:
-Letter from R.F. Dunn to NRC Document Control Desk, "10 CFR 50.46 ECCS c: *:: >:.:;,_;Eva1*uation Model Significant Change/Error Report," dated October 17, 2012, NOC-AE-12002912(ML12310A383)
- 2. Letter from R.F. Dunn to NRC Document Control Desk,, '.'10 GF:R 50.46 Thirty-Day Report of Significant ECCS Model Changes," dated Jµ)y.7, _2014, NOC-AE-14003157 (ML 14205A014) . " . In accordance with the requirements of 1 O CFR 50.46 (a)(3)(ii), STP.Nuclear Operating Company (STPNOC) is submitting a 30-day report for a significant' change in the STP Unit 1 Emergency Core Cooling System (ECCS) Model. It was discovered that the 1 O CFR 50.46 :*report issued within 30 9f $TP _Unit 1. reach_ir;ig 100% rated-thermal* power which was achieved Ori Dece-mber 3o,* 2'015: cO'nditiC:m
.. Report-16-2783 was written to address this oversight.
.. In Reference 2, STPNOC identified that the value for the hot assembly average rod Gamma Energy Deposition Model-( GEOM) for Unit_ 1 Cygle 19, ,increased 0.0041 _above coolant accident (LOCA)re'road i:mfety analysis checklist (RSAC) limit of 0.984. This change resulted in an estimated increase of 3°F in Peak Clad Temperature (PCT) from the 211 ?°F reported in Reference
- 1. For Unit 1 Cycle 20, there is no PCT penalty due to GEOM violation, so the 3°F penalty no longer applies, and PCT reduces from 2120°F back to 2117°F. Since the absolute value of PCT changes to the Analysis of Record exceeds 50°F, the change is considered significant in accordance with 10 CFR 50.46 (a)(3)(i).
No-s-chedule for reanalysis-is proposed since the 'unit_ 1 Cycle PQT remains below the 10 CF.R 50.46(b)(1) limit of 2200°F. _ -' . -. , There are no commitments in this letter. ,-,
any ques'tions
,,_ . --
- _. ' -__ .-:_.;*",*:
- _*: . ,:. :: .. --.. _. :'.,_ _-_
- .
.-'_: -*-. : . r". * -'. .. , * , I r * ' ', 'r ' '* < ( I ' *' ! . . ' -.. -* . STI: 34283123 . : .. * . .' .: '* ' -* * ** ,1 *** 1 ,, *' Roland F. Dunn _
.. , Nuclear Fuel and Analysis \ *' -* *.) ; f* -
cc: (Paper Copy) Regional Administrator, Region IV U.S. Nuclear Regulatory Commission 1600 East La-mar Boulevard Arlington, TX 76011-4511 Lisa M. Regner Senior Project Manager U.S. Nuclear Regulatory Commission One White Flint North (08H04) 11555 Rockville Pike Rockville, MD 20852 NRC Resident Inspector U. S. Nuclear Regulatory Commission P. 0. Box 289, Mail Code: MN116 Wadsworth, TX 77 483 STI: 34283123 (Electronic Copy) NOC-AE-16003341 Page 2 of 2 Morgan, Lewis & Bockius LLP Steve Frantz, Esquire U. S. Nuclear Regulatory Commission Lisa M. Regner NRG South Texas LP John Ragan Chris O'Hara Jim van Suski! CPS Energy Kevin Pollo Cris Eugster L. D. Blaylock Crain Caton & James. P.C. Peter Nemeth City of Austin Elaina Ball John Wester Texas Department of State Health Services Richard A. Ratliff Robert Free South Teras Project Electric Genemting Station P.O. Ba.-289 1-'hdsworth.
Texas 77./83 U. S. Nuclear Regulatory Commission Attention:
Document Control Desk Washington, D.C. 20555-0001 South Texas Project Unit 1 February 24, 2016 NOC-AE-16003341 10 CFR 50.46 (a)(3)(ii)
Docket No. STN 50-498 1 O CFR 50.46 Thirty-Day Report of Significant ECCS Model Changes
References:
-Letter from R.F. Dunn to NRC Document Control Desk, "10 CFR 50.46 ECCS c: *:: >:.:;,_;Eva1*uation Model Significant Change/Error Report," dated October 17, 2012, NOC-AE-12002912(ML12310A383)
- 2. Letter from R.F. Dunn to NRC Document Control Desk,, '.'10 GF:R 50.46 Thirty-Day Report of Significant ECCS Model Changes," dated Jµ)y.7, _2014, NOC-AE-14003157 (ML 14205A014) . " . In accordance with the requirements of 1 O CFR 50.46 (a)(3)(ii), STP.Nuclear Operating Company (STPNOC) is submitting a 30-day report for a significant' change in the STP Unit 1 Emergency Core Cooling System (ECCS) Model. It was discovered that the 1 O CFR 50.46 :*report issued within 30 9f $TP _Unit 1. reach_ir;ig 100% rated-thermal* power which was achieved Ori Dece-mber 3o,* 2'015: cO'nditiC:m
.. Report-16-2783 was written to address this oversight.
.. In Reference 2, STPNOC identified that the value for the hot assembly average rod Gamma Energy Deposition Model-( GEOM) for Unit_ 1 Cygle 19, ,increased 0.0041 _above coolant accident (LOCA)re'road i:mfety analysis checklist (RSAC) limit of 0.984. This change resulted in an estimated increase of 3°F in Peak Clad Temperature (PCT) from the 211 ?°F reported in Reference
- 1. For Unit 1 Cycle 20, there is no PCT penalty due to GEOM violation, so the 3°F penalty no longer applies, and PCT reduces from 2120°F back to 2117°F. Since the absolute value of PCT changes to the Analysis of Record exceeds 50°F, the change is considered significant in accordance with 10 CFR 50.46 (a)(3)(i).
No-s-chedule for reanalysis-is proposed since the 'unit_ 1 Cycle PQT remains below the 10 CF.R 50.46(b)(1) limit of 2200°F. _ -' . -. , There are no commitments in this letter. ,-,
any ques'tions
,,_ . --
- _. ' -__ .-:_.;*",*:
- _*: . ,:. :: .. --.. _. :'.,_ _-_
- .
.-'_: -*-. : . r". * -'. .. , * , I r * ' ', 'r ' '* < ( I ' *' ! . . ' -.. -* . STI: 34283123 . : .. * . .' .: '* ' -* * ** ,1 *** 1 ,, *' Roland F. Dunn _
.. , Nuclear Fuel and Analysis \ *' -* *.) ; f* -
cc: (Paper Copy) Regional Administrator, Region IV U.S. Nuclear Regulatory Commission 1600 East La-mar Boulevard Arlington, TX 76011-4511 Lisa M. Regner Senior Project Manager U.S. Nuclear Regulatory Commission One White Flint North (08H04) 11555 Rockville Pike Rockville, MD 20852 NRC Resident Inspector U. S. Nuclear Regulatory Commission P. 0. Box 289, Mail Code: MN116 Wadsworth, TX 77 483 STI: 34283123 (Electronic Copy) NOC-AE-16003341 Page 2 of 2 Morgan, Lewis & Bockius LLP Steve Frantz, Esquire U. S. Nuclear Regulatory Commission Lisa M. Regner NRG South Texas LP John Ragan Chris O'Hara Jim van Suski! CPS Energy Kevin Pollo Cris Eugster L. D. Blaylock Crain Caton & James. P.C. Peter Nemeth City of Austin Elaina Ball John Wester Texas Department of State Health Services Richard A. Ratliff Robert Free