Thursday, March 14, 2013

San Onofre Unit 2 Retainer Bars Could Cause Massive ☢ Leakage

In an accident like a main steam line break at San Onofre, the badly designed retainers bars in Unit 2 could actually make things much worse by causing more damage to any of the 9,727 already fatigued tubes in each of its steam generators which could lead to additional leakage of highly radioactive reactor core coolant and/or cause a nuclear incident or worse a nuclear accident like Fukushima!

Radioactive Leaks and ruptures can happen without notice:


The NRC has decided in AIT follow-up report dated 11/09/2012, “Item 3. “(Closed) Unresolved Item 05000362/2012007-03, ‘Evaluation of Retainer Bars Vibration during the Original Design of the Replacement Steam Generators” as a non-cited violation in accordance with Section 2.3.2 of the NRC’s Enforcement Policy.”  However, as shown below, SCE/MHI’s failure to verify the adequacy of the retainer bar design as required by SCE/MHI’s procedures have resulted in plugging of several hundred tubes in the brand new replacement generators. This has resulted in these violations:

1. Failure to meet NRC Chairman Standards on Nuclear Safety by SCE,
2. Failure to meet Senator Boxer’s Committee on Environment and Public Works
(EPW) Standards on Nuclear Safety by SCE,
3. Failure to enforce SCE Edison Contract Document instructions to MHI by SCE,
4. Failure to meet SONGS Technical Specifications by SCE,
5. Failure to meet general design criteria (GDC) in Appendix A, “General Design
Criteria for Nuclear Power Plants,” to 10 CFR Part 50, “Domestic
Licensing of Production and Utilization Facilities GDC 14, “Reactor
Coolant Pressure Boundary” by SCE/MHI,
6. Failure to demonstrate that Unit 2 retainer bars will maintain tube bundle
geometry at 70% power due to fluid elastic instability during a main line
steam break (MSLB) design basis event, and
7. SCE/MHI took shortcuts by avoiding the 10 CFR 50.90 License Amendment
Process under the false pretense of “like for a like” replacement steam
generator.  SCE added 377 more tubes, increased the average length of the
heated tubes and changed the thermal-hydraulic operation of the RSGs without
proper safety analysis and inadequate 10CFR 50.59 Evaluation.
This intentional action to produce more thermal megawatts out of the
RSGs compromised safety at SONGS Unit 2 due to the failure of 90
percent through wall thickness of a tube by the inadequate design of the
etainer bar.

Recommended Actions:

NRC San Onofre Special Panel is requested to resolve the above listed Allegations and/or Violations within 30 days of receipt of this email and prior to granting SCE’s permission to do any restart "testing" of Unit 2. Answer all allegations factually, don't just void them.
See Full Document:
Media Alert: San Onofre Retainer Bar Problems