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@dean sent you a gmail

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@Peter good comments.. to complicate matters further the NRC recently will issue new guidance with the help of USGS to provide new rules on NPP locations between the east and west part of the country. thats one problem, the USGS comes up with new seismic assumptions that then have to be fed through complicated analyses and it is hard to keep up with determining what must be done at each plant based on the USGS data and then implement some sort of timeline schedule to get the modifications etc completed and upgrades to the TSR...

More on San Onofre. Now they think all 3 units may have steam generator problems. The damaged unit has ruined pipes in the steam generator. They replaced these all in 2010. enformable.com

@Ian are you looking for the CSV file?

Power Reactor Event Number: 47628
Facility: SAN ONOFRE
Region: 4 State: CA
Unit: [ ] [ ] [3]
RX Type: [1] W-3-LP,[2] CE,[3] CE
NRC Notified By: DOUG FOOTE
HQ OPS Officer: JOHN KNOKE Notification Date: 01/31/2012
Notification Time: 22:58 [ET]
Event Date: 01/31/2012
Event Time: 17:30 [PST]
Last Update Date: 01/31/2012
Emergency Class: NON EMERGENCY
10 CFR Section:
50.72(b)(2)(iv)(B) – RPS ACTUATION – CRITICAL Person (Organization):
JEFF CLARK (R4DO)
SCOTT MORRIS (IRD)
LOUISE LUND (NRR)
Unit SCRAM Code RX CRIT Initial PWR Initial RX Mode Current PWR Current RX Mode
3 M/R Y 100 Power Operation 0 Hot Standby
MANUAL TRIP DUE TO A PRIMARY TO SECONDARY LEAK GREATER THAN 30 GAL/HR”At 1505 PST, Unit 3 entered Abnormal Operation Instruction S023-13-14 ‘Reactor Coolant Leak’ for a steam generator leak exceeding 5 gallons per day.”At 1549 PST, the leak rate was determined to be 82 gallons per day. At 1610 PST, a leak rate greater than 75 gallons per day with an increasing rate of leakage exceeding 30 gallons per hour was established and entry into S023-13-28 ‘Rapid Power Reduction’ was performed.”At 1630 PST, commenced rapid power reduction per S023-13-28 ‘Rapid Power Reduction’. At 1731 PST, with reactor power at 35% the Unit was manually tripped. At 1738 PST, Unit 3 entered Emergency Operation Instruction S023-12-4 ‘Steam Generator Tube Rupture’.”At 1800 PST the affected steam generator was isolated.”All control rods fully inserted on the trip. Decay heat is being removed thru the main steam bypass valves into the main condenser. Main feedwater is maintaining steam generator level. No relief valves lifted during the manual trip. The plant is in normal shutdown electrical lineup.Unit 2 is presently in a refueling outage and was not affected by this event.The licensee has notified the NRC Resident Inspector. The licensee has issued a press release.

This was not the first time a leak-scare has occurred at the San Onofre plant. In November 2011, a level 1 alert was issued at the plants but the appropriate alarms did not go off.

San Onofre just finished replacing both steam generators attached to Unit 2 and 3. Many other plants of similar design have conducted similar upgrades, but none, according to the NRC, has had a rupture after being installed.

The leak is not Edison’s first problem with the new steam generators.

In September 2009, Edison met with NRC officials to discuss weld defects that were detected in both of the 640-ton crucibles.

The utility notified the NRC in August 2009 that the replacement generators for Unit 3 had developed cracks in a weld that connects a 5-inch-thick steel plate that supports each generator’s innards.

Inspections found that use of a special metal-gouging tool caused the welds to become brittle and crack. Mitsubishi Heavy Industry, the company that built the generators for Edison, fixed the cracked welds, and they passed NRC inspection.

Sounds like San Onofre will be down for a long time while they sort this out. Does anyone know when the CA nuclear referendum vote will be or if they have enough signatures to get it on the ballot?

@dean thanks.

@Ian raw data: www.tepco.co.jp the pressure data is in columns 4-8 (3rd after date column)

Steam Dump Control - The steam dump control system reacts to prevent a reactor trip following
a sudden loss of electrical load. The steam dump control system also removes stored energy and
residual heat following a reactor trip so that the plant can be brought to equilibrium no-load
conditions without actuation of the steam generator safety valves. The steam dump control system
also provides for maintaining the plant at no-load or low-load conditions to facilitate a controlled
cooldown of the plant.
Rapid Power Reduction - For large, rapid load rejections (turbine trip or grid disconnect from
50-percent power or greater) a rapid nuclear power cutback is implemented. This results in a
reduction of thermal power to a level that can be handled by the steam dump system.

Rapid Power Reduction Rod Selection
The number of rods needed to obtain this power reduction is dependent on the core burnup during
the fuel cycle. In addition, if a large load rejection (grid disconnect) is initiated at a part-power
condition (50-percent to 100-percent power), then a reduced number of control rods need to be
released. Therefore, a means is provided to have the control system select which rods will be
released by the rapid power reduction system.
The selection of the rods that are released during the rapid power reduction is based on a thermal
power measurement. The thermal power is integrated over time to arrive at a core burnup.
Depending on the core burnup and the plant power level, the choice of the control rods to be
released by the rapid power reduction system is determined. Capability is provided for the
operator to correct the integrated burnup periodically based upon a more detailed burnup
calculation.

shows the criteria for reportable leak rates 5 gallons per day.. abnormal operation instruction s023-13-14, then leak increased with the increasing leake rate in excess of 30 gal/hour... pushed them into rapid power reduction and subsequent NRC and other notification

www.edison.com Contact: Media Relations, (626) 302-2255

ROSEMEAD, Calif., Feb. 1, 2012 � Southern California Edison (SCE), operator of the San Onofre Nuclear Generating Station, continues to plan for the repair of the steam generator tube leak in Unit 3 following a precautionary shutdown Tuesday. Sensitive monitoring instruments at Unit 3 continue to show no change in radiation levels that would be detectable off-site.

Operators responded quickly yesterday to indications of a steam generator tube leak based on readings from highly sensitive instruments designed to detect this condition, and in time to take action to prevent any potential change in detectable radiation exposure outside the plant boundary. Operators safely shut the plant down and isolated the component that contained the leaking tube within four hours of detecting the indications.

Currently, operators are cooling down Unit 3 and reducing pressure in the plant, which is the method to stop the tube from leaking. They are meticulously following prescribed procedures written specifically for addressing a tube leak condition.

"There was no threat then, nor is there now any danger to the public or to plant workers," said Pete Dietrich, senior vice president and Chief Nuclear Officer for Southern California Edison. "Our operators performed exactly as they are trained to perform and took prompt action to ensure we did not create a situation involving any challenge to the health and safety of the public," Dietrich said.

Unit 2 is currently offline for a planned maintenance, refueling and technology upgrade outage. Service will not be affected; Southern California Edison has ample reserve power to meet customer needs.

hi Dean!

www.urscorp.com West (SGT), a URS/AREVA NP joint venture company, is providing project management, planning, engineering and construction services to prepare and install four new steam generators each at Units 1 and 2 at Diablo Canyon Nuclear Power Plant, which is located near Avila Beach along the central California coast, for the Pacific Gas and Electric Company of San Francisco. The plant provides electricity for approximately three-million households in northern and central California.

@lilly.. true.. the article had the steam generator and I wondered if it had a mitsubishi sign on it

Bird life badly hit by nuclear fallout in Japan www.irishtimes.com

@dean I don't know of anyone specifically studying wildlife in the zone. I am sure someone is. The domestic animals, it is hard to tell what is lack of food/shelter vs. radiation contributing to death and illness.