ML13155A189
| ML13155A189 | |
| Person / Time | |
|---|---|
| Site: | San Onofre  |
| Issue date: | 05/12/2013 |
| From: | Hawkins B - No Known Affiliation |
| To: | Rules, Announcements, and Directives Branch |
| References | |
| NRC-2013-0070, 78FR22576 00417 | |
| Download: ML13155A189 (5) | |
Text
UNITED STATES NUCLEAR REGULATORY COMMISSION WASHINGTON, D.C. 20555-0001 ml D'-vi rn cji r-Jn r-r'77l qL+ (ý ('-4/3 SUNSI Review Complete Template = ADM -013 E-RIDS= ADM-03 Add= B. Benney (bjb)
CHAIRMAN Resource From: Bill Hawkins [billiee123456@gmail.com]
Sent: Sunday, May 12, 2013 1:45 AM
Subject:
San Onofre Sad Saga Continued
-NRC/SCE/MHI/SCE Experts and Public Awareness Series-SCE Designed and MHI Fabricated 21st Century Safest & Innovative Replacement Steam Generators
Reference:
Nuclear Regulatory Commission
[Docket No. 50-361; NRC-2013-00701, Application and Amendment to Facility Operating License Involving Proposed No Significant Hazards Consideration Determination; San Onofre Nuclear Generating Station, Unit 2]Kendra UIrich states, "Edison's restart scheme has major holes in it: the root cause of the problems hasn't been found, Edison's own experts disagree on even the secondary cause of the issues, and disagree on the length of time left before another accident could occur -- which could be somewhere in the range of a few months to a little over a year. In short, Edison is rushing to restart the reactor in time for summer, when they can maximize their profits, which -- unfortunately for the people of Southern California
-- means putting safety at the bottom of the list. But the Nuclear Regulatory Commission has the power to stop the restart, by rejecting Edison's license amendment and allowing the public to get involved in the process." Dr. Joram Hopenfeld and SONGS Insiders say,"Operating at 70% power may reduce risk, but it is no guarantee of safety. "Maybe the vibrations wouldn't be as severe, but it doesn't mean they are going away," Hopenfeld said. SONGS Insiders say, "If an accident like Main Steam Line Break happens, (an) emergency plan is not geared to handle such a public safety devastation.
Those things have never been racticed or demonstrated in a drill scenario." According to a highly placed retired SCE manager,
Conclusions:
Edison says, "It had no knowledge of the SONGS SGs issues until January 2012" is completely misleading and erroneous.
Based on an internal San Onofre investigation conducted last year and rejection of SCE & MHI Root Cause Evaluation and NRC AIT Report, it is concluded that Edison Engineers most likely knew of SG issues in 2006, but did not speak up loud enough for fear of retaliation or firing. Therefore, truth can only be proven, if Edison team of California Professional Engineers (Mechanical, Pipe Supports, Civil and Steam Generators) are made to testify under oath to prove that they had no PRIOR knowledge of the steam generator issues until January 2012. In addition, all the meeting notes and videos of SCE/MHI Joint AVB Team need to be examined in detail, which hopefully are in possession of SCE and MHI and have not been tampered (Billion Dollar Question).
Issues: MHI Root Cause states, "Also MHI and SCE recognized that the SONGS RSG steam quality (void fraction) was high and MHI performed feasibility studies of different methods to decrease it.Several design adjustments were made to reduce the steam quality (void fraction) but the effects were small. Design measures to reduce the steam quality (void fraction(e.g., using a larger downcomer, using larger flow slot design for the tube support plates, and even removing a TSP)) by a greater amount were considered, but these changes had unacceptable consequences and MHI and SCE agreed not to implement them. Among the difficulties associated with the potential changes was the possibility that making them could impede the ability to justify the RSG design under the provisions of 10 C.F.R. §50.59. Thus, one cannot say that use of a different code than FIT-Ill would have prevented the occurrence of the in-plane FEI observed in the SONGs RSGs or that any feasible design changes arising from the use of a different code would have reduced the void fraction sufficiently to avoid tube-to-tube wear. For the same reason, an analysis of the cumulative effects of the design changes including the departures from the OSG's design and MHI's previously successful designs would not have resulted in a design change that directly addressed in-plane FEI." I A review of Edison Procurement documents for replacement generator indicates that these documents were prepared, checked and certified by an Edison Design Team of California Professional Engineers (Mechanical, Pipe Supports, Heat Transfer, Civil and Steam Generators.)
These documents state, "The tables in the 'Original Design Data' column specify the values for the existing steam generators and in the "Replacement Design Data" column specify the values for the RSG, either imposed by Edison or proposed by the Supplier.
Edison prefers that the imposed values be maintained to the greatest extent possible, but understands that some trade-offs may be necessary, and is willing to work with the Supplier to accommodate these trade-offs.
The Supplier may address with Edison any deviations from the values specified.
The Supplier shall prepare and submit for Edison's review a Design Review Item List, which shall identify the design issues and fabrication/assembly activities, which if not correctly handled/performed may result in inadequate RSG performance, or degradation of performance, or reduction of the RSG service life. The list shall provide a detailed description of the issues, explain how they are addressed in the RSG design and fabrication/assembly plan or procedures, and identify the areas where trade-offs may be required." Some of the Edison specified parameters responsible for higher steam quality (higher void fraction, fluid elastic instability) are as follows: OSG -San Onofre Original Combustion Engineering Steam Generators RSG -San Onofre SCE Designed and MHI Fabricated 21st Century Safest & Innovative Replacement Steam Generators Steam .Generaor Thermal Rating .(@100% Reactor Power -MWt -oSG 1,705.i. RSG -1,729 Steam Pressure (@1 00%power)
-Beginning of Life.(Guaranteed Value).-.
psia -OSG -900; RSG -817 RCS Design Flow (0% Tube Plugged) -gpm -OSG -198,000, RSG -209,880 (16%)Circulation Ratio (@.1.00%power)
-OSG -3.2, RSG -3.3 817 Steam Moisture Content, %,-OSG < 0.20 -RSG -< 0.10 Increasing the heat transfer area by 11%, Addition of 377 new tubes (4% heat transfer:
area)Increasing .theaverage.!length of heated tubes by 50. inches (Equivalent addition .of.650 tubes or.7% heat.tra.nsfer area)There are hundreds of operating steam generators in the world, which have avoided fluid elastic instability by keeping the void fractions below 98.5% (Ref. AREVA Operational Assessment data for 5 steam generators, NUREG-1841, NRC Approved Power Uprate Applications, etc.) by operating at steam pressures above 900 psia, Steam Moisture Content < 0.20 % and circulation ratios above 4.MHI Root Causes states, "SCE/MHI AVB Design Team recognized that the design for the SONGS RSGs resulted in higher. steam quality (void fraction) than previous designs and had considered making changes to the design to reduce the void fraction (e.g., using a larger downcomer, using larger flow slot design for the tube support plates, and even removing a TSP)." So, we assume, that Edison Engineers must have foreseen the impact the problem of high void fractions on increased tube vibrations and refused to make the changes, because it could have impeded the ability to justify the RSG design under the provisions of 10 C.F.R. §50.59, delayed the construction schedule, increased the costs and reduced the profit margins. Increasing the circulation ratios meant reducing the void fractions by increasing the steam pressures, reducing pressure losses, reducing moisture content and less thermal output from the generator.
High void fractions cause higher tube vibrations, fluid elastic instability and tube-to-tube wear. MHI/SCE AVB Team missed the boat on Academic Research Papers (2003 through 2006), NUREG-1841 Industry Bench Marking (World's largest CE 2 replacement steam generators installed in 2002 and partly owned by SCE) and ignored the well-established elementary principles of physics, SG tube vibrations, nucleate boiling, heat transfer, void fractions and circulation ratios by refusing to lower the RSG void fractions.
The Original Combustion Engineering Steam Generators operated at 900 psi and a void fraction of 96.1%. That is why these steam generators did not suffer fluid elastic instability in 28 years of operation.
Increasing the heat transfer area by 11 %, addition of 377 new tubes (4% heat transfer area), the average length of heated tubes by 50 inches (Equivalent addition of 650 tubes or 7% heat transfer area), the steam generator thermal output by 24 MWt to make more profits and refusal to reduce the void fractions was a joint decision, which we assume, was known by members of the MHI/SCE AVB Team and SCE Management, which included the Edison Engineers.
Edison Steam Generator Expert states, "The contract for design, fabrication and delivery of the RSGs was awarded to Mitsubishi Heavy Industries Ltd. (MHI). As specified, the RSGs were supposed to be a replacement in-kind for the OSGs in terms of form, fit and function.
At the same time, however, the RSG specification included many new requirements derived from both industry and SONGS operating experience, and the requirement to use the best and most suitable materials of construction.
These requirements were aimed at improving the RSG longevity, reliability, performance and maintainability.
Also, the specification called for very tight fabrication tolerances of the components and sub-assemblies, especially the tubesheet and the tube U-bend support structure.
In addition, SONGS steam generators are one of the largest in the industry, which called for innovative design solutions and improved fabrication processes when working on the RSGs. Conceivably, the MHI and Edison project teams faced many tough challenges throughout the entire project in the design; manufacturing and QC areas, when striving to meet the specification requirements.
Both teams jointly tackled all these challenges in an effective and timely manner. At the end, MHI delivered the RSGs, which incorporated all the latest improvements found throughout the industry, as well as innovative solutions specific to the SONGS RSGs. In Unit 2, the RSGs were installed and tested in 2009/10 and in Unit 3 in 2010/11. The RSG post-installation test results met or exceeded the test acceptance criteria for all specified test parameters, thus properly rewarding the effort put into their fabrication." The closure of SONGS' units 2 and 3 has cost $470 million, which has been absorbed by the region's customers and the company's shareholders.
Southern California Edison, is trying to figure out its next move: That is, it is asking the Nuclear Regulatory Commission to allow it to restart Unit 2 and to gradually rev it up to 70 percent of its capacity.
If it is unable to do so, the utility says that it may retire both units at the end of this year."Without a restart of Unit 2, a decision to retire one or both units would likely be made before year-end 2013," says Theodore Craver, chief executive of Edison International that is the holding company for SoCalEd, in a conference call. "There are many potential decision scenarios involving Unit 2 and Unit 3. They all have different implications for grid reliability, customer costs, attainment of greenhouse gas and air quality objectives." Other than permanently shutting down the units, SoCalEd could choose to work with the vendor that installed the steam generators to fix the problem. That would take five years, meaning that costs would continue to add up while the facility would not be bringing in any revenues.All this has created a mess between SoCalEd and Mitsubishi Corp., which installed the steam generators that have defective parts. The vendor says that its liabilities are limited to $139 million, which is considerably less than the overall maintenance costs, not to mention to the loss of business.It also says that it had informed the utility in 2009 of the malfunctions, which led to the radiation leaks in 2012.3 Mitsubishi maintains that a strategic business decision was made in 2009 to fix the problem, as opposed to re-install different parts. SoCalEd, however, denies that supposition, adding that it had no knowledge of the issue until January 2012. That's when the tubes began leaking.Now both companies are being accused by citizen groups and policymakers of improprieties and caring more about profits than they do safety. Specifically, Rep. Ed Markey, D-Mass. wants the U.S.Securities and Exchange Commission to probe into whether investors were intentionally misled."Investors presumably would want to know whether a company is choosing not to implement additional safety protocols because such actions might require a nuclear reactor to go through a more strenuous licensing process," says Rep. Markey, who is top Democrat on the House Natural Resources Committee. "Such choices could be evidence of poor management or even possible civil liability." 4