|The DAB Safety Team has serious concerns about SCE’s Unit 2’s Restart Reports, because these reports do not meet the NRC Chairman’s Safety Definition nor do they satisfy the NRC’s 10CFR50, Appendix B Quality Assurance Standards.|
Ultimate Responsibility: The top U.S. nuclear safety official, the Chairman of the NRC said earlier this month the operator of the idled San Onofre nuclear plant is ultimately responsible for ensuring the quality of equipment and work provided by vendors or its contractors. Addressing nuclear industry executives in Atlanta, Nuclear Regulatory Commission Chairman Allison Macfarlane touched upon challenges at the idled San Onofre nuclear station and highlighted the responsibilities of the plant license holder. "This obligation extends to the licensees’ use of vendors and contractors," McFarlane said. "The licensee is ultimately responsible for the work done by their vendors and contractors to ensure they meet our quality assurance requirements." [Source: U-T San Diego November 7-2012]
Question Number 1: Why the massive tube damage at San Onofre aka SONGS?
More than 100 Replacement Steam Generators (RSGs) in the USA with Alloy 690 TT Tubes have been designed, fabricated and tested by Westinghouse, BWI and other vendors, including Fort Calhoun by MHI. These steam generators have only had very few plugged tubes according to NUREG-1841 and Professor Dan Hirsch’s September 12, 2012 Report. MHI has built more than 100 Steam Generators since 1970. Only Mihama Unit 2 SG built by MHI had a single tube rupture due to a displaced Anti Vibration Bar. The question is, why did the SONGS Replacement Steam Generators suffer so much severe degradation in such a short time? Is this the fault of SCE’s in-house design team, their Performance Specifications coupled with their numerous design changes and or the MHI Fabrication/Testing Technology combined with Faulty Thermal-Hydraulic Computer Codes? The DAB Safety Team and the Public expected that SCE and their three NEI Qualified, “US Nuclear Power Plant Designers”, Westinghouse, AREVA and MHI would arrive at a concise and clear answer (Meeting the NRC Quality Assurance requirements as stated by NRC Chairman Allison Macfarlane) to this puzzling question in the Unit 2 Return to Service Report.
Observations On Number 1: The SCE Cause Evaluation Report, Operational Assessments reports prepared by SCE, AREVA and Westinghouse, and MHI Technical reports conflict and contradict with each other on the causes and extent of degradation pertaining to the fluid elastic instability in SONGS Unit 2 Steam Generator Replacement Generators (RSGs) and Tube-to-AVB gaps in both Unit 3 and Unit 2 RSG’s. MHI further states that specific causes that resulted in tubes being susceptible to fluid-elastic excitation are not yet completely known. Furthermore SCE has not plugged all the 2 tubes in one of the Unit 2 RSG’s nor have they removed the Retaining Bars (RB’s) as recommended by MHI in their latest NRC notification, issued after their preliminary report!
Operational Note On Number 1: Unit 2 was running at higher steam pressures than Unit 3 and lower thermal power than Unit 3. That is why the void fractions were lower than 98.5% and no fluid elastic instability occurred in Unit 2. AREVA, Westinghouse, MHI and SCE missed this key observation in the SCE Unit 2 restart Plan. At least one person working at SONGS spoke up about this fact but nobody listened to him and it was ignored because everybody in SCE was focused on blaming MHI to recover the insurance money and or absolving themselves of all blame. The DAB Safety Team will explain the probable reasons other than the ECT results for Unit 3’s increased clearances between the anti-vibration bars and the tubes in their next Press Release.
Comments And Observations About Number 1: It is the opinion of the DAB Safety Team’s Expert Panel, former NRC Staff and SONGS Concerned Insiders that this Westinghouse Operational Assessment is full of holes based on incomplete inspection data, under-conservative computer modeling and is in effect, just “Smoke & Mirrors,” because:
(1) SCE Engineers have either not provided, or they are withholding important information from Westinghouse because of “The consequences of being Wrong, Terminated or Fired,”
(2) Due to competing and proprietary interests between Westinghouse and MHI, Westinghouse Engineers do not have all the MHI Manufacturing Details and are just guessing in their Deterministic Operational Analysis of Unit 2, the second worst Degraded Replacement Steam Generators in the Operating US Nuclear Fleet,
(3) Due to Time Pressure exerted by SCE, Westinghouse Staff did not have proper time for independent validation of all facts, documentation and data provided by SCE’s Engineers, in their original report.
(4) Since nobody knows what really happened, all the Parties have a shared interest to “Operate Unit 2 at reduced power as a nuclear “RSG Tube Wear Test Lab”.
UCS Observations: The Union of Concerned Scientists (UCS) has serious concerns about Southern California Edison’s (SCE) restart plans for San Onofre Unit 2. In a 10/12/2012 letter submitted to the Nuclear Regulatory Commission (NRC), David Lochbaum, Director, Nuclear Safety Project, identified the following issues:
· Unit 2 replacement steam generator 2SG89 has significantly more wear indications per number of supports than does [Unit 2] replacement steam generator 2SG88. Until the reason for this marked difference between the wear degradation for the Unit 2 replacement steam generators is understood, the operational assessment performed for future operation is suspect.
· Since all four replacement steam generators came from the same manufacturer, were of the same design, made of the same materials, assembled using the same procedures, and operated under nearly identical conditions in twin reactors, the reason for this marked difference is unclear… [the] explanation is not well documented and therefore appears to be more convenient than factual.
· The document states that the owner will “administratively limit Unit 2 to 70% reactor power prior to a mid-cycle” outage to inspect the replacement steam generators. What are the legal and safety consequences if the reactor power were to increase to 75%, 85% or 100% power, advertently or inadvertently? The NRC has licensed San Onofre Unit 2 to operate at 100% power. What would legally prevent the owner from restarting Unit 2 and increasing its output to the NRC licensed limit? The NRC’s enforcement program includes sanctions when its regulations are violated, but nothing if promises are broken. If the NRC agrees that reactor operation at less than 100 percent power is warranted, it should enforce that reduction with an order or comparable legally enforceable document. However even that will not necessarily prevent its occurrence. Has NRC even considered that fact?
· Table 8-1 of Enclosure 2 and its accompanying text attempt to explain how operating Unit 2 at 70% power will prevent the tube-to-tube wear (TTW) experienced on Unit 3 by comparing it to an anonymous reactor (called Plant A). Reliance on one suspect data point (Plant A) is hardly solid justification for operation at 70% power being acceptable.
· There is no justification in this 80-plus-page document for an operating duration of 150 days.
· There are no legal means compelling the plant’s owner to shut down Unit 2 after 150 days of operation at or above 15% power.
· A temporary nitrogen-16 radiation detection system will be installed prior to the Unit 2 startup. However, there is no commitment to use it after startup, or to keep it in service should it stop functioning. The detection system is proposed as a defense-in-depth measure, but there is no assurance it will be operated. Furthermore, it will NOT provide the necessary warning that tube rupture is eminent. It will only indicate that it is already occurring.
· Attachment 6 to Enclosure 2 has proprietary information redacted. Section 1.4 of Enclosure 2 states that the owner used AREVA, Westinghouse Electric Company LLC, and Intertie/APTECH to review the operational assessment. At least one of these companies manufactures replacement steam generators and would therefore be a competitor to Mitsubishi Heavy Industries (MHI), which made the replacement steam generators for San Onofre. If the owner did not withhold the proprietary information from MHI’s competitors, why withhold it at all? If SCE did withhold the proprietary information from these reviewers, what is the value of their independent, but limited, review?
Conclusions And A Final Question: The DAB Safety Team Agrees with NRC Chairwoman Allison Macfarlane that SCE is ultimately responsible for the work done by their vendors and contractors to ensure they meet our quality assurance requirements. Based upon the review of all Restart Documents and all the issues identified by David Lochbaum, The DAB Safety Team’s Expert Panel along with their SONGS Concerned Insiders opinion that these reports are full of holes and based on incomplete inspection and or operational data, under-conservative computer modeling and represents Smoke & Mirrors which does not meet the NRC Chairwoman’s Safety Definition nor the standards outlined in the 10 CFR Part 50, Appendix B, “Quality Assurance Criteria for Nuclear Power Plants and Fuel Reprocessing Plants.”
The Trillion Dollar Question is now, how can the NRC’s Region IV in good faith, even consider having a November 30 Public Hearing, except to possibly give SCE a Billion Dollar Christmas present, by allowing them to restart their damaged Unit 2 without a 50.90 License Amendment Process by completely ignoring the safety of all those living in Southern California due to the potential of having a Trillion Dollar Eco-Disaster at San Onofre because of their already well documented massively damaged RSG tubes?
The DAB Safety Team: November 26, 2012
Copyright November 26, 2012 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 Attorneys.