NEWS: Palo Verde Nuclear plant unexpectedly shuts down.

One of our nation's largest power plant shut down unexpectedly on Monday. It was the first time that all three units at the plant shut down and even one of the two diesel backups did not seem to want to work properly. The disruption caused 65,000 residents to lose power for about an hour. There were also some people affected in New Mexico and Northern California.

 

Nuclear regulators inspect Palo Verde, plant remains inoperable


Could this have been another cyber attack like the attack on several internet sites?

[edit on 16-6-2004 by Muaddib]

[edit on 6-16-2004 by Valhall]

There was a story about Palo Verde last week about a shut down of Unit 3.
They said that was the fourth shutdown of a reactor at that site this year.

This was the fourth unexpected shutdown at Palo Verde this year. Three of those involved radiation leaks.

In addition to those shutdowns, Unit 3 last month had a non-radioactive vent-line leak.

azcentral

I also just found this at NIN.

" The �distribution problem� caused all three nuclear reactor units at the Palo Verde nuclear power plant shut down due to an unidentified disruption of questionable origin. The number 3 Unit will remain shutdown for the remainder of this week due to a �control system malfunction. "

Excerpted from.
www.homelandsecurityus.com...

Per the NRC:

ALERT DECLARED - REACTOR TRIP DUE TO LOSS OF OFF SITE POWER

On June 14, 2004, at approximately 07:44 Mountain Standard Time (MST) all three units at the Palo Verde Nuclear Generating Station experienced automatic reactor trips coincident with a grid disturbance and loss of offsite power in the Palo Verde Switchyard. Unit 2 declared an ALERT Emergency Plan classification at approximately 07:54 due to a loss of AC power to essential buses reduced to a single power source for greater than 15 minutes such that any additional single failure would result in a station blackout. Subsequently, at 09:51 Unit 2 downgraded the Emergency Plan classification to a NOTIFICATION OF UNUSUAL EVENT when AC power was restored from a single essential bus to both essential buses. Units 1 and 3 declared a NOTIFICATION OF UNUSUAL EVENT at 07:53 MST due to a loss of offsite power to essential buses for greater than 15 minutes. The NOTIFICATION OF UNUSUAL EVENT was terminated for all 3 units at 12:07 MST.

Unit 1 and 2 manually initiated a Main Steam Isolation System ESF actuation by procedure. Unit 3 received an automatic Main Steam Isolation System ESF actuation.

Due to the loss of offsite power, the Emergency Plan Technical Support Center (TSC) was unavailable. The Unit 2 Satellite TSC was to be staffed by the Emergency Response Organization in response to the loss of assessment capability. Power to the TSC has since been restored.

The Emergency Plan ALERT declaration includes staffing of the Joint Emergency New Center to address expected media interest.

All three units were at normal operating temperature and pressure prior to the trip. All CEAs inserted fully into the reactor cores. All Emergency Diesel Generators (EDGs) (2 per unit) associated with each of the 3 units started as expected in response to the loss of offsite power to their safety buses. Unit 2's train "A" EDG started, but did not indicate volts or amps and was manually shutdown.

The offsite power grid had several perturbations for approximately one hour following the event but has been stable since. LCO 3.8.1, AC Sources - Operating, was entered in each unit as a result of this event. Heat removal is to atmosphere via atmospheric dump valves in natural circulation. Main steam safety valves may have lifted for a brief time. Restoration of forced reactor coolant circulation is pending assurance that the offsite power grid can reliably support the load. No major equipment was inoperable prior to the event that contributed to the event.

All 3 units are stable at normal operating temperature and pressure in Mode 3. The event did not result in any challenges to fission product barriers and there were no adverse safety consequences as a result of this event. The event did not adversely affect the safe operation of the plant.

source

So, other than one diesel generator having a problem (that's why there's redundant systems), the problem was with the electrical grid, not the plant. The control systems at nuclear power plants are not connected to the internet, so there's no way a hacker could control anything (besides, most plants in the US still rely on analog, not digital, controls).

The problem was not only one diesel motor having problems, read the link again it said "the plant's power was reduced to one motor working." And if the problem was an offsite power failure, it could very well have been a hacker since the problem did not generate inside the nuclear plant which is pretty much secure.

Right, all three units were tripped due to the loss of offsite power (not due to the malfunctioning diesel generator - that is what initiated the ALERT declaration). Tripping the reactor is a safety precaution that is taken whenever the grid goes down, and isn't a "problem" per se. And you're right, the grid problems may have been caused by hackers - my point was merely that the problem was outside the plant.

One thing I found interesting on the NRC site was that San Onofre had problems with offsite power (Frequency off) about 3 min. before Palo Verde had problems with off site power. The Frequency only dropped down to 59.7Hz, but that is something that is very carefully controlled. Someone playing with the Grid?

I live in Phoenix...about 20 miles from Palo Verde. It was interesting that our local news, yesterday, headlined with the fact that something like 70,000 residents were without power, due to a power grid failure. Then, as an aside, they said that parts of the Palo Verde plant was shut down as a precaution. My husband and I both thought that a little strange at the time.
So far, mum's the word, from our local media..who, apparently, don't want to panic anyone. Of course, everyone is speculating as to the real cause and most suspect some kind of hacking.
joey