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Proposed Changes To San Onofre's Decommissioning Fund

Part 3 - SONGS $569 Million Replacement Steam Generators

4. Challenges and Rewards of Innovative Design of RSGs

Boguslaw J. Olech (Southern California Edison Co.), Tomoyuki Inoue (Mitsubishi Heavy Industries Ltd.)

This paper describes major challenges associated with, and rewards resulting from, an innovative/improved design of the Replacement Steam Generators (RSGs) for the San Onofre Nuclear Generating Station (SONGS). The SONGS consists of twin plants (Units 2 and 3) rated at 3358 MWt (~1180 MWe) each. SONGS Unit 2 began commercial operation in 1983 and Unit 3 in 1984. The plants were originally equipped with CE Model 3340 recirculating steam generators. The Original Steam Generators (OSGs) employed heat transfer tubing made of Alloy 600 Mill Annealed (MA) and the carbon steel egg-crate type tube supports. The OSGs were designed for a 40-year service life. Continuing to operate with highly degraded steam generators can involve substantial economic risks from forced outages, extended refueling outages, as well as the direct costs of inspections and repairs. To address these risks, and consistent with industry experience, Edison has set a 21.4% plugging level as the technical end-of-life of the SONGS OSGs. The worst case forecast indicated that this plugging level could be reached by approximately 2012. 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.

Continued Part 4

September 19, 2012 at 8:08 p.m. ( | suggest removal )

Proposed Changes To San Onofre's Decommissioning Fund

Part 2 - SONGS $569 Million Replacement Steam Generators

3. Improvements in MHI SG Technology

There is no standard design for a replacement SG because the specifications and plant requirements vary among customers. The dimensions of recently exported SGs, in which widely varied specifications were applied. However, by applying the following latest advanced technologies to all SGs, improvements were made which cope with all past problems such as tube corrosion, vibration and wear, fatigue, and water hammer, and products which satisfy customers' advanced demands for heat transfer capability and moisture content are being supplied.
(1) Tube material of high nickel alloy TT690 with excellent corrosion resistance.
(2) Outstanding tube support plate design, tube expansion technology in tube sheets.
(3) Tube support structure at U-bends with high support function.
(4) High-performance moisture separators.

Of these advanced demands for recent replacement SGs, items (3) and (4) deserve special attention. The tube support structure at a U-bend is a unique design with reduced flow resistance while assuring a high support function by increasing the number of support points. Together with excellent assembly technology during manufacturing, high reliability against vibration and wear of heat transfer tubes is achieved. MHI has developed a small, high-performance moisture separator by optimizing the geometry of the parts based on extensive field pressure tests. As a result, replacement SGs corresponding to power up-rating and/or advanced moisture requirements can be designed.

Ref. MHI, Ltd. Technical Review Vol. 43 No. 4 (Dec. 2006)

Continued Part 3

September 19, 2012 at 8 p.m. ( | suggest removal )

Proposed Changes To San Onofre's Decommissioning Fund

SONGS $569 Million Replacement Steam Generators

1. Background:

More than 100 Replacement Steam Generators (RSGs) in the USA have been installed with Alloy 690 TT Tubes that were designed, built and tested by Westinghouse, BWI and MHI (at Fort Calhoun). These steam generators have very few plugged tubes according to NUREG-1841 and Prof. Dan Hirsch's September 12, 2012 Report.

MHI has built more than 100 Steam Generators (SG) since 1970. Only Japan’s Mihama Unit 2 SG built by MHI had one tube rupture due to a displaced Anti Vibration Bar and that caused an IAEA Level 3 Nuclear accident!

2. Mihama Nuclear Accident Lessons Learnt by MHI

On February 9th, 1991, a heat transfer tube (SG tube) in a steam generator of the No.2 pressurized water reactor at the Mihama nuclear power station of the Kansai Electric Power Company broke off during a rated output operation. As a result, about 55 tons of primary cooling water leaked out from the SG tube into the secondary cooling loop, and the reactor was scrammed by operation of the ECCS (Emergency Core Cooling System). The failure of the SG tube was caused by fretting fatigue resulting from contact of the SG tube with the supporting plate for the SG tubes, because the AVB, which functions to prevent flow-induced vibration, was not inserted deep enough onto the SG tubes in the steam generator. The scale of the accident was ranked "level 3" on the international nuclear events scale (INES).

After the accident, a detailed examination of the AVB for the SG tubes in the steam generators of all reactors in the Kansai Electric Company was carried out. As a result, lack of sufficient insertion depth of the AVB was found in some heat exchangers. These AVBs were replaced with new ones and installed at the designated depth in the steam generators. Moreover, the steam generator of the No.2 pressurized water reactor was also replaced with a new one, because many of the SG tubes were removed from the generator for failure analysis.

Lessons Learnt and Causes: Ignorance, Insufficient Knowledge, Poor Understanding, Production, Hardware Production, Production of Machinery and Equipment, Heat Exchanger, SG tube, Supporting Plate, AVB, Installation, Regular Operation, Nonobservance of Procedure, Error of Mounting Position, Lack of Insert Depth, Failure, Fracture/Damage, Flow-induced Vibration, Fretting Fatigue, Failure of SG tube, Usage, Maintenance/Repair, Inspection, Lack of Inspection, Failure, Large-Scale Damage, Leakage of Coolant

KITUNAI, Yoshio (Japan Crane Association)
KOBAYASHI, Hideo (Yokohama National University)

Continued Part 2

September 19, 2012 at 7:57 p.m. ( | suggest removal )

NRC To Hold Public Meeting On San Onofre Oct. 9

SOW-DAB Team Humble Suggestions - NRC Public Meeting scheduled for San Onofre on Oct. 9

Here are some advanced questions for Reporters to ask NRC prior to the Public Meeting scheduled for San Onofre on Oct. 9

1. Has the MHI Root Cause Evaluation been completed and available for Public Viewing on the NRC Website?

2. When will the SCE Restart Plan and supporting documents be available for Public Viewing on the NRC Website?

3. Will the NRC Chairwoman, other Commissioners and/or Senator Barbara Boxer be available at the Public Meeting to assure public of a thorough, unbiased and complete investigation by NRC?

4. Besides SCE, will MHI Representatives be available to answer questions by the Public Groups?

5. Which interest groups will be consulted to have representation on the Table? How many Representatives? Who will decide?
Friends of the Earth
Fairewinds Energy Education
San Clemente Green
The Committee to Bridge the Gap
General Public

September 13, 2012 at 6:20 p.m. ( | suggest removal )

Proposed Changes To San Onofre's Decommissioning Fund

Cyber Security Initial Awareness Training - SONGS Leaders Proudly Say "SONGS Procedure Violation, No Problem, Problem has been addressed”. When Reporters ask SONGS and NRC, NRC and SONGS either don’t Respond or Reply with Pride, "No Problem, Problem has been addressed.

When the SONGS Leaders listed below and more than 1000 employees are out of out of compliance with a SONGS procedure, It is a significant breakdown of Quality Assurance Program, NEGATIVE Management Behavior. “You cannot borrow from Peter and pay Paul.” By citing that these leaders have taken the EIX Cyber Security Initial Awareness Training, It is OK to Violate A SONGS Procedure. This does not fit the Model Behaviors and Expectations of the SONGS Leaders specified in the SONGS Excellence Book, which is signed by the SONGS SVP/CNO Pete Dietrich. SONGS has a successful and dark history of procedure violations, culture of harassment, discrimination, false perceptions, cover-up and nuclear retaliation. Is it the way to operate an Unsafe INPO 4 Plant with the worst safety record and Steam Generator Problems. On the Top, SCE charges the Rate Payers 700 Million Dollars for defective SCE designed and MHI Fabricated Radiation Steaming Crucibles (after opposition by SDG&E) and continue to charge 54 million dollars a month with no lights?


Cyber Security Initial Awareness Training and Annual Requalification Training is a SONGS Specific Procedural Requirement (In Effect for the Last Three years) for all Station Employees with Unescorted Red Badge Access. Based on an Audit of T2000 Computer System Training Records, the following leaders never took SONGS Cyber Security Initial Awareness Training (Data Verified on 5/19/2012)

SONGS LEADERS never took the cyber security initial awareness training
Pete Dietrich - SVP/CNO - Executive Management
Tom McCool - Plant Manager - Executive Management

Annual requalification cyber security awareness training expired
Doug Bauer Site Manager/Vice President
Executive Management - Cyber Security Program Management Sponsor

T2000 - Out of 15 Senior Leadership Team (SLT) members, 5 have never taken the Cyber Security Initial Awareness Training and the Continuing Yearly Training (ENCODE 3NPCSAT). 6 Leaders Cyber Security Awareness Continuing Training (ENCODE 3NPCSAT) is overdue. These 11 Leaders are not qualified for Life Time Cyber Security Technical Training (ENCODE 3T90816). At least 4 of these 11 Leaders are member of the SONGS Emergency Response Organization (ERO Roster) and their training gaps (ENCODE 3NPCSAT) MAY POTENTIALLY impact compliance with the federal regulations.

ARC - Review Request - Continuation of NN 201992954 - 3NPCSAT GAPS
3NPCSAT - SONGS Nuclear Power Plant Cyber Security Awareness is required WBT for personnel that hold unescorted access to the Protected Area. The requirement is stated in section of SO123-XXI-TPD-GET.

September 12, 2012 at 11:13 a.m. ( | suggest removal )

Proposed Changes To San Onofre's Decommissioning Fund

Note: For Continuation see Part 5 above


What went wrong at San Onofre is a classic tale of Bad Equipment Design, Financial Greed and Time Pressures, Regulatory Negligence/Cover-up, Unapproved Tests and Experiments, Poor Industry Benchmarking, Consistent Equipment Failures, Poor Maintenance Practices, Bad Management Structure, Retaliation against Nuclear Safety Concerns and Repeat Human Performance Errors. Like Ace Hoffman Says, “The Citizens of Southern California, one of the most beautiful places on earth, are put at great risk by continued operation of San Onofre. It doesn't generate cheap power. It is the most expensive power in the world (when all the costs to society are taken into account). And it's obviously not reliable -- reliable "base load capacity", that has always been a claim of the nuclear industry and nuclear energy institute.”

Frankly, San Onofre has the worst record of addressing nuclear personnel/nuclear safety concerns (e.g. Billon Dollars Wasted Steam Generators, Fire/Safety, Lack of Station Ownership of Emergency Preparedness, Poor Maintenance, Inefficient Work Control, Uncontrolled Configuration Control, Lack of Adherence to Convoluted/Complicated Procedures, Inhuman Attendance Policy, Low Employee Morale, Harassment, Retaliation, Intimidation, Demotions, Be Here Now, Cyber Security Program, Lack of Solid Team Work & Alignment between Divisions, etc.).

Like One SONGs Worker says, “These Profit Driven Hungry Tigers are running San Onofre like a “Nazi Concentration Camp.” The present SONGS Management Structure does not have the capability/ability to Operate Nuclear Units and address these personnel/nuclear safety concerns. Existing SONGs employees with New Reformed/Humble Management can be retrained to operate these Gas-fired Units in an efficient and cost-effective manner. Public, Rate Payers, EIX Share Holders, Workers, NRC, CPCU, Workers, San Clemente Green, Friends of the Earth and News Media will be happy. Humans have only had one life to live. SONGS does not give the appearance of a Democratic and Civil America. SONGS Retaliatory Managers have to be taught to treat the workers with dignity and respect. Every SONGS Worker has a Constitutional Right to live in harmony and peace. One of the best SONGS Shift Manager had an argument with the Plant Manager and the Shift Manager said, I do not want to operate the damaged Unit 2 and put the public lives and my License on Line. So just like the SONGS Fire Engineer, who resigned to serve the public and protest against the nuclear ratiliation and harrassment, the Shift Manager also did the Honorable Thing, resigned and left for a nice vacaation. More Later

September 12, 2012 at 9:35 a.m. ( | suggest removal )

Proposed Changes To San Onofre's Decommissioning Fund

Note: For Continuation see Part 4 above


San Onofre Nuclear Generating Station Units 2 & 3 should be decontaminated and decommissioned (dismantled) without delay because Southern Californians do not want to take the risk of a Fukushima Nuclear Disaster in their Backyard. The Aging San Onofre Watergate Radiation Nightmare should be replaced by new 4-500 MW Gas Fired Units with New Intelligent Management, which respects and not retaliates against workers for earning Performance Bonuses.

Sunlight is the Earth's primary source of energy. The sun is a gigantic nuclear reactor. Human beings have to rely for the time being on Nuclear Power Plants to produce safe and cheap electricity. This is crucial for their existence and to be able t6 enjoy the modern comforts provided by the 21st Century Technology due to shortage of non-renewable fossil fuels and expensive environmental friendly renewable energy technologies. No Government, Rules, Organization, Technology, Safety and Design Features, and Quality Assurance/Inspection Procedures can guarantee 100% protection of the human beings from radiological accidents caused by Natural Disasters. However, there is no moral/legal excuse for radiological accidents caused by Bad Equipment Design/Fabrication Methods, Operator Negligence, Regulatory Negligence, Unapproved Tests and Experiments, Consistent Organizational Weakness, Poor Maintenance Practices, Fires, Retaliatory Profit- Motivated Management and Repeat Human Performance Errors.

Southern Californians do not want damaged San Onofre Replacement Steam Generators to be restarted for them to act as a Test Laboratory for NRC/SCE/MHI to determine the real root cause of tube damage. The restart approach to reduced power operations is unacceptable because, “Many more damaged tubes in the steam generators due to steam voiding, Flowering Effects and other factors can break catastrophically and create a Southern California’s Fukushima. SCE wants to run Unit 2 (Unit 3 is planned to be defueled), so they can make some money and avoid an investigation by the CPUC of what went wrong.

September 12, 2012 at 9:28 a.m. ( | suggest removal )

Proposed Changes To San Onofre's Decommissioning Fund


SONGS Unit 2 – SONGS Shift Managers and Operating Weaknesses Continued

• Lack of Stringent OPS/NTD Evaluation and Remediation Criteria for SM/STA/OPS Crew to achieve excellence and eliminate above shortcomings to prevent DEP Failures

• Lack of practice by the Operating Crews, CRS, STA and EC following the coaching/critique provided by the OPS SM Supervisor and NTD Evaluators. This statement was confirmed by NOD during a discussion with a former Shift manager this morning.

NRC Report States, “Assuming that a steam line break would cause the degraded steam generator tubes to rupture during a “T/2” exposure period of 6 months yielded a change in the large early release frequency of 4E-6/yr. However, SCE informed the NRC that a calculation is under review that will likely indicate that the differential pressures generated by a steam line break would not be large enough to rupture the degraded tubes as long as operators successfully implemented their emergency procedures. If this is confirmed, the risk associated with steam line breaks will be significantly reduced.

Southern Californians may not be lucky this time, because there is a 6 percent probability per the SONGS emergency plan records for the last 6 years of Plant operators making a mistake. Therefore, this event with or without an earthquake/main steam line break can cause a potential reactor meltdown of SONGS Unit 2 resulting in a Fukushima Daiichi Nuclear and Chernobyl disaster in Southern Californians Backyard.

Southern Californians, are you willing to live with the impact? If not, write to your Congressman or City Council to Protest the Restart of SONGS Unit 2. After all you pay the bills for Southern California Edison, Nuclear Regulatory Commission, California Public Utilities Commission Officials and all the Elected Politicians in the Country. Would you allow a Nuclear Disaster to happen, while these guys are enjoying their lives, partying and filling their pockets without any regard for your safety?

September 12, 2012 at 9:18 a.m. ( | suggest removal )

Proposed Changes To San Onofre's Decommissioning Fund


SONGS Unit 2 - The total plugging for Unit 2 is 205 tubes in steam generator 2E088, and 305 in 2E089. If Southern Californians allow SONGS Unit 2 to Restart even at reduced power, the SONGS Unit 2 steam generators are also susceptible excessive vibration of tubes in the U-bend region of the steam generators to the extent that the tubes can rub against each other (tube-to-tube interactions) causing excessive wear and loss of structural integrity. What it means is that without proper repairs of Unit 2 and exact root cause determination, an operational transient due to localized highly dry steam (No water) and inadequate tube support structure in the U bend region can cause several already weakened (damaged) and more than 200 plugged tubes to rupture like soft cookies. NRC Report States that the resident inspectors determined that crew supervision exercised effective oversight of plant status, crew performance, and control room command and control.

The SONGS Emergency Plan Root Cause Evaluation Problem Statement in April 2012 by the SONGS Nuclear Oversight Department states , “ Below are some of the weaknesses witnessed during review and or observation of LOCT/DEP Evaluations, EP Drills and based on discussions with the Shift Managers. Each weakness may be attributed to one or the other DEP Miss-classifications. Some of these weaknesses were also identified by a Nuclear Oversight Board Member based on his observation of the August 2011 EP drill.

• Unclear and confusing EALs and less than adequate Basis Documents

• Too many Priority Reading Assignments to clarify the EALs and Basis Document

• Lack of solid teamwork between the Operating Crew, CRS, STA and EC. Crew members were confused and concerned about their roles and responsibilities. Crew members held back or failed to provide information, which resulted in SM and CRS to trip the reactor.

• Poor communications between the Operating Crew, CRS, STA and EC. Briefs were ineffective at focusing on the crew priorities. Three way communication were not used for direction or when providing information relative to plant status.

• Poor diagnostics/interpretation of the transient events by the Operating Crew, CRS, STA and EC. Serious omissions, delays, or errors made in interpreting indications resulting in degraded plant conditions. Failed to use, or misused, or misinterpreted indications that resulted in improper diagnosis.

• Procedures were not followed correctly which impeded plant recovery or caused unnecessary degradation of plant conditions. Crews did not recognize EOI Entry Conditions.

• Failure of the STA to provide consistent & independent check of the EAL by EC (See NNs 201915131, 201932015 & 201937568).

Note: For Continuation see Part 4

September 12, 2012 at 9:16 a.m. ( | suggest removal )

Proposed Changes To San Onofre's Decommissioning Fund


NRC Report states SONGS Unit 3 steam generators had experienced excessive vibration of tubes in the U-bend region of the steam generators to the extent that the tubes rubbed against each other (tube-to-tube interactions) causing excessive wear and loss of structural integrity. Your staff determined that the vibration was caused by the steam conditions in the U-bend region of the steam generators by a phenomenon called “fluid elastic instability.” The NRC inspection team
concluded that the steam generators’ design and configuration did not provide the necessary margin to prevent this phenomenon. Although the steam generator tube degradation from this phenomenon observed in Unit 2 steam generators was not as severe, the NRC team concluded that both units’ steam generators were of similar design with similar thermal hydraulic conditions and configurations. Therefore, SONGS Unit 2 steam generators are also susceptible to this phenomenon.

SONGS Unit 3 - Eight SONGS Unit 3 tubes in steam generators built by Mitsubishi failed in-situ pressure test after the tube leak accident in January 2012. The NRC AIT Report says that plant operators responded to the event in a manner that protected public health and safety and all safety systems performed their functions to support the safe shutdown and cool down of the plant. The release resulted in an estimated 0.0000452 (4.52 E-5) mrem dose to the public. However, the loss of steam generator tube integrity is a serious safety issue that must be resolved prior to further power operation.

If eight tubes in Unit 3 steam generator would have ruptured, SONGS accident could have been many times worse than Mihama Nuclear Disaster, if the Intelligent Shift Managers and Operating Crews had not detected the Unit 3 leak in a timely manner and brought the plant to a safe shutdown. Southern Californians were lucky this time? The Steam generator tubes in Unit 3 are so damaged, that SCE is taking the fuel out of the reactor. According to SONGS reliable Sources, Mitsubishi is planning to relocate to the SONGS jobsite for 4 years, so they can determine what went wrong and repair Unit 3, so SCE can operate the Unit 3 again and make money. The question is can Southern Californians Trust NRC, CPCU, SCE and MHI to do that again without a detailed and open public investigation and risk their health, property and economy?

Note: For Continuation see Part 3

September 12, 2012 at 9:14 a.m. ( | suggest removal )