The DAB Safety Team: January 2, 2013
Media Contact: Don Leichtling (619) 296-9928 or Ace Hoffman (760) 720-7261
The NRC AIT Team's Review Of The SONGS Original Steam Generators (OSGs) And Their Replacement Steam Generators (RSGs) Requires Another Immediate NRR Investigation
The DAB Safety Team has transmitted the following to the Chairman of the NRC, Offices of Nuclear Regulator Regulations, Atomic Safety Licensing Board and NRC AIT Team Chief.
NRC Office of Nuclear Reactor Regulation has requested Edison in a December 26, 2012 letter the following additional information (RAI #32): "Please clarify how the information submitted by SCE demonstrates: (1) that the structural integrity performance criterion in TS 5.5.2.11.b.1 is met for operation within current licensed limits up to the licensed Rated Thermal Power (RTP or 100% Power), or (2) provide an operational assessment that includes an evaluation of steam generator Tube-to-Tube Wear (TTW) for operation up to the RTP."OSGs Design: The SONGS OSG design had shown to be susceptible to out-of-plane tube through-wall wear and severe corrosion of the tube supports. The maximum Stability Ratio calculated by SCE Engineers in 2001 Power Uprate Application was 0.675 (< 1 so no Fluid Elastic Instability (FEI)). According to Enclosure 2 of SONGS Unit 2 Return to Service Report, OSGs were operating at 1709 MWt (Reactor Thermal Power or RTP), vapor fraction (96.1%), Interstitial or gap velocity of 22.9 feet/second.
DAB SAFETY Team Comments. re: OSGs Design: The OSGs operated for 28 years, did not experience abnormal tube leak or tube-to tube wear (TTW) for operation up to 1709 RTP. No FEI occurred (stability ratio <1). Furthermore, the OSG FSAR analyses demonstrated that the offsite radiological release doses due to an OSG tube rupture, main steam line break or an inadvertent opening of an OSG Atmospheric Dump valve with single active failure were at the time, well within the federal 10CFR100 guidelines.
SCE Profit-Motivated RSGs Design Changes: According to Enclosure 2 of SONGS Unit 2 Return to Service Report, the SONGS RSGs RTP specifications were changed to 1729 MWt. To accommodate this additional 20 MWt, SCE engineers changed the vapor fraction (99.6%), Interstitial or gap velocity of 28.3 feet/second, added 377 additional tubes and increased the length of each tube by more than 7 inches. NRC AIT Team report states, "SCE Design Specification SO23-617-1 did not address specific criteria for stability ratio and does not mention fluid-elastic instability." Note: All these changes were made: (1) In a rushed "hush-hush" manner to generate extra profits for SCE and its Shareholders, (2) SCE Engineers prepared a defective 10CFR 50.59 safety evaluation hiding these numerous untested and unanalyzed changes under the pretense of "like for like" between the OSGs and the RSGs. Then they convinced NRC Region IV to review these without a formal NRC 50.90 License Amendment Process and Evidentiary Public Hearings.
NRC AIT Team review of SCE 10CFR 50.59: The NRC AIT Team stated in its report, "Based on the updated final safety analysis report description of the original steam generators, the team determined that the steam generators major design changes were reviewed in accordance with the 10 CFR 50.59 requirements. The team determined that no significant differences existed in the design requirements of Unit 2 and Unit 3 replacement steam generators. Based on the updated final safety analysis report description of the original steam generators, the team determined that the steam generators major design changes were reviewed in accordance with the 10 CFR 50.59 requirements. The NRR technical specialists reviewed SCE's 10 CFR 50.59 evaluation against 10 CFR 50.59(c)(2)(viii) which requires that licensees obtain a license amendment pursuant to 10 CFR 50.90 prior to implementing a proposed change if the change would result in a departure from a method of evaluation described in the final safety analysis report (as updated) used in establishing the design bases or in the safety analyses. The NRR technical specialists found two instances that failed to adequately address whether the change involved a departure of the method of evaluation described in the updated final safety analysis report." (emphasis added) The changes were as follows: (a) Reactor Coolant System Structural Integrity - Use of ABAQUS Computer Program instead of ANSYS: SCE's 50.59 evaluation incorrectly determined that using the ABAQUS instead of ANSYS was a change to an element of the method described in the updated final safety analysis report did not constitute changing from a method described in the updated final safety analysis report to another method, and as such, did not mention whether ABAQUS has been approved by the NRC for this application. (b) Main Steam Line Break Mass-Energy Blowdown Analysis & Tube Wall Thinning Analysis - Use of ANSYS Computer Program instead of STRUDL and ANSYS Computer Programs: SCE's 50.59 evaluation did not mention whether the method has been approved by NRC for this application.
The DAB Safety Team's Comment's re: SCE RSGs Catastrophic Design Changes: About a year ago, on January 31, 2012, in SONGS Unit 3, one tube started leaking radioactive coolant in one of brand new replacement steam generators (RSG's) E-088 that was reverse-engineered by SCE and manufactured by a complacent Mitsubishi Heavy Industries (MHI). The leak started small, but increased enough in a very short period of time to warrant the emergency shutdown of the reactor. When tested later (in March 2012), eight (8) steam generator tubes (wear range 72-100%, length of wear 23-34 inches) in the newly replaced San Onofre Unit 3 RSG E-088 failed "in-situ" main steam line break pressure testing and therefore were plugged, after only after 11 months of operation, something that had never happened before in the history of the US Nuclear fleet. Additionally, several hundred of the Alloy 690 Thermally Treated tubes were also plugged due to tube-to-tube wear. SONGS RSG's now have more damaged and/or plugged tubes than all the rest of the US reactor fleet combined. Southern Californians were very lucky, because a potentially serious nuclear accident in Unit 3 was narrowly avoided. This accident could have potentially caused a nuclear meltdown and threatened the health and safety, economy and environment of Southern California. NRC website also states, "The severity of one of the wear indications at a Unit 2 (steam generator tube to*) retainer bar was significant enough (90 percent thru-wall) to warrant in-situ pressure testing. This pressure test confirmed the structural integrity of this tube (there was no leakage)." This means that Southern Californians lucked out again, because Unit 2 just happened to be shutdown for refueling, otherwise, this tube could have also leaked radiation due to any design bases accident or unanticipated transients. Finally, the NRC AIT Team displayed poor judgment in their review of SCE's 10 CFR 50.59 Evaluation and the NRR Specialists wisely questioned the inadequacy SCE's 10 CFR 50.59 Evaluation. The NRR now needs to review the NRC AIT Teams' failure to enforce NRC Regulations and find out what exactly happened to ensure the Public Safety. * Wording added for clarification
DAB SAFETY Team Comments to NRR RAI#32: By operating the "Defectively Designed and Degraded" Unit 2 Replacement Steam Generators (RSGs) at 100% Reactor Thermal Power:
(1) SCE CANNOT DEMONSTRATE [with all the World's Expert's Assistance - emphasis added] that ALL in-service RSG tubes would retain structural integrity over the full range of normal operating conditions (including startup, operation in the power range, hot standby, cool down and all anticipated transients included in the design specification) and design basis accidents in accordance with SONGS Unit 2 Technical Specifications structural integrity performance criterion in TS 5.5.2.11.b.1.
(2) SCE CANNOT PROVIDE AN ACCEPTABLE OPERATIONAL ASSESSMENT TO THE NRC, which demonstrates that steam generator Tube-to-Tube Wear (TTW) for operation up to the RTP would not cause a tube leak in order to comply with Code of Federal Regulations, 10 CFR Part 50 Appendix A, General Design Criteria 14, "Reactor Coolant Pressure Boundary" shall have "an extremely low probability of abnormal leakage...and gross rupture."
Please See DAB Safety Team Paper Response to NRR RAI #32 - Technical for additional details. This press release will be posted on the web at this link: DAB Safety Team Documents.
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ABBREVIATIONS AND ACRONYMS:
· AIT: NRC's Augmented Inspection Team
· AVB: Anti Vibration Bar
· CE: Combustion Engineering, builders of SONGS original steam generators
· CNO: Chief Nuclear Officer
· DAB: DAB Safety Team
· FEI: Fluid Elastic Instability
· MHI: Mitsubishi Heavy Industry
· MSIV: Main Steam (line) Isolation Valve
· MSLB: Main Steam Line Break
· MWt: Mega-Watts Thermal
· NRC: Nuclear Regulatory Commission
· NRR: NRC's Office of Nuclear Reactor Regulations
· PVNGS: Palo Verde Nuclear Generating Station
· QA: Quality Assurance
· RAI: Request Additional Information
· RSG: Replacement Steam Generator
· RTP: Reactor Thermal Power
· SCE: Southern California Edison
· SG: Steam Generator
· SONGS: San Onofre Nuclear (Waste) Generating Station (alternate abbreviation: SONWGS)
· TS: Technical Specifications (for operation of a NPP)
· TTW: Tube-to-Tube Wear
The DAB Safety Team: Don, Ace and a BATTERY of safety-conscious San Onofre insiders plus industry experts from around the world who wish to remain anonymous. These volunteers assist the DAB Safety Team by sharing knowledge, opinions and insight but are not responsible for the contents of the DAB Safety Team's reports. We continue to work together as a Safety Team to prepare additional DAB Safety Team Documents, which explain in detail why a SONGS restart is unsafe at any power level without a Full/Thorough/Transparent NRC 50.90 License Amendment and Evidentiary Public Hearings. For more information from The DAB Safety Team, please visit the link above.
Our Mission: To prevent a Trillion Dollar Eco-Disaster, like Fukushima, from happening in the USA.
Copyright January 1, 2013 by The DAB Safety Team. All rights reserved. This material may not be published, broadcast or redistributed without crediting the DAB Safety Team. The contents cannot be altered without the Written Permission of the DAB Safety Team Leader and/or the DAB Safety Team's Attorney
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Ace Hoffman
Author, The Code Killers:
An Expose of the Nuclear Industry
Free download: acehoffman.org
Blog: acehoffman.blogspot.com
YouTube: youtube.com/user/AceHoffman
Carlsbad, CA
Email: ace [at] acehoffman.org
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