3 Mile Island Reactor Shuts Down

AP ^ | November 2 2006

[jmc1969]

The reactor at Three Mile Island, site of the nation's worst nuclear accident, shut down Thursday, but radiation was not released and there was no danger to the public, company and federal officials said.

A faulty instrument reading triggered the automatic shutdown, officials said. It was the first shutdown of Unit 1 since 1997, said Ralph DeSantis, a spokesman for the plant's operator, AmerGen Energy Co. LLC.

The unit, which opened in 1974, shut off at 1:35 p.m. and remained down Thursday evening.

The plant, about 10 miles southeast of Harrisburg, was the site of the nation's worst nuclear accident when a partial meltdown occurred in the Unit 2 reactor in March 1979.

[festus]

Thats what I was thinking.

In ohio not far from a nuke plant where my father was working men in white outfits and geiger counters came over to take some readings. They assured him there was nothing to worry about it was all routine...................

[Palladin]

Never believe them when they say "We're from the government and we're here to help you."

Especially if they're wearing white suits and carrying Geiger counters.

[burzum]

Environmental surveys are part of every nuclear plant. They do them because it is probably a 5th generation "what if?" clause and because the public expects them to do it, not because they had a massive radioactive discharge.

The logic is something like this: What if our radioactive discharge procedures and logs were wrong (which were reviewed independently by probably more than 10 people), the plant operation logs were wrong (reviewed again), procedures for preventing inadvertent discharges were performed incorrectly (and the logs were wrong), the local radiation meters failed, and the local surveys were performed incorrectly, could it be possible to contaminate the countryside? I guess we had better check!

[sefarkas]

where I worked spiked off the meter

#1 A 'spike' is not a reading. #2 Playing with the gain on the instrument will make it read whatever you want it to read. I suggest you probe your 25 or so year old memory to see if the instruments were current with the calibration program outlined in your QA manual. Unsubstantiated claims such as the one you make may be entertaining, but your claim has no credibility.

"... It has been estimated that about 2.5 million Ci of noble gases (about 0.9 percent of the core inventory) and 15 Ci of radioiodine (about 0.00003 percent of the core inventory) were released to the environment at TMI-2 (NUREG/CR-1250). [Also referred to as the Rogovin report.] No other radioactive fission products were released in measurable quantities. It has been estimated that the maximum cumulative off-site radiation dose to an individual was less than 100 mrem (NUREG/CR-1250; President's Commission 1979). The total population exposure has been estimated to be in the range from about 1000 to 5000 person-rem. (This range is discussed on page 2 of NUREG-0558.) This exposure could statistically produce between zero and one additional fatal cancer over the lifetime of the exposed population of approximately 2 million in the site area. The same population receives about 240,000 person-rem each year from natural background radiation, and approximately a half million cancers are expected to develop in this group over the lifetime of the population (NUREG/CR-1250; President's Commission 1979), primarily from causes other than radiation. Trace quantities (barely above the limit of detectability, below allowable limits, and less than that from fallout due to nuclear tests) of radioiodine were found in a few samples of milk produced in the area. No other food or water supplies were affected. "

See more at http://www.nrc.gov/reading-rm/doc-collections/nuregs/staff/sr1437/v1/part05.html

[Roses0508]

I did computer support at a nuclear power plant for 7 years. What I learned is the hardest thing about running a nuclear plant is keeping it running - they are designed so that any small deviance shuts the thing down automatically for safety's sake.

[Erasmus]

I'm guessing here, but I think that Palladin was engaging in "double secret sarcasm."

< }B^)

[Erasmus]

Then again, I could be wrong.

(^8{><}8^)

[Jimmy Valentine]

The thing that always grinds me is that the reactor was perfectly safe and shut itself down properly; thesafety mechanisms worked.

The cause of the problem was the operators in the control room who were screwing around playing grab ass instead of monitoring the equipment.

They should all be in jail for life.

[burzum]

Well the event report is in and it appears that it was actually a scram.

Power Reactor	Event Number: 42957
Facility: THREE MILE ISLAND Region: 1 State: PA Unit: [1] [ ] [ ] RX Type: [1] B&W-L-LP,[2] B&W-L-LP NRC Notified By: JOE SHOFFNEN HQ OPS Officer: JOHN MacKINNON	Notification Date: 11/02/2006 Notification Time: 14:53 [ET] Event Date: 11/02/2006 Event Time: 13:34 [EST] Last Update Date: 11/02/2006
Emergency Class: NON EMERGENCY 10 CFR Section: 50.72(b)(2)(iv)(B) - RPS ACTUATION - CRITICAL	Person (Organization): JOHN WHITE (R1)

Unit	SCRAM Code	RX CRIT	Initial PWR	Initial RX Mode	Current PWR	Current RX Mode
1	A/R	Y	100	Power Operation	0	Hot Shutdown

Event Text

AUTOMATIC TURBINE TRIP/ REACTOR TRIP DUE TO INVALID LOW CONDENSER VACUUM SIGNAL


"At 1334 on 11-2-06 an Automatic Reactor Trip occurred from 100% power. All systems functioned as required. One safety valve stuck open on both OTSGs. They subsequently re-seated. An employee working on the roof at the time of the trip fell off a ladder and injured his leg. Emergency medical was contacted to assisted with the injured worker. Two fire trucks and an ambulance was dispatched to the site to remove the injured worker. The worker was not contaminated. There is no indication of any OTSG Tube leaks. Initial investigation indicates the reactor tripped, due to a turbine trip due to an invalid low vacuum signal."

State and local officials will be notified of this event by the licensee.


I&C Techs were performing maintenance on one of the low pressure vacuum switches. An electrical fault fed to the other two low pressure vacuum switches causing a 2 out of 3 signal which resulted in a turbine trip followed by a reactor trip signal, as expected. All rods fully inserted into the core. One safety valve (9 safety valves on each OTSG) on each Once Through Steam Generator stuck open. OTSG "B" safety relief valve was open less than one minute. There are no leaking OTSG tubes. A condensate relief valve located in the turbine building opened/shut - nobody injured. The ICS (Integrated Control System) operated as expected. All emergency core cooling systems and the emergency diesel generators are fully operable plus the electrical grid is stable.

A licensee working on the industrial coolers on top of the industrial building, standing on a ladder, fell off the ladder when OTSG relief valve opened. Licensee either broke or badly sprained his leg.

The NRC Resident Inspector was informed of this event by the licensee.

[coloradan]

Not true. The Geiger counters where I worked spiked off the meter.

They would probably spike off the meter if you gave them a dental x-ray or two, too. You get a lead apron when they operate the x-ray machine, after all. It is entirely possible that the average person in the city surrounding TMI received two dental x-ray's-worth of ionizing radiation.

[Palladin]

Well, I was there. My neighbor's son, a nuclear physicist with the government, called her on the first day of the crisis and told her to GET THE HELL OUT OF TOWN.

She and all the neighbors did just that.

By the second day, all the doctors and nurses left.

By the third day, you couldn't get gas at the gas station or cash from the ATM because all the SMART people had drained them before evacuating.

[coloradan]

Well, I was there. My neighbor's son, a nuclear physicist with the government, called her on the first day of the crisis and told her to GET THE HELL OUT OF TOWN.

She and all the neighbors did just that.

By the second day, all the doctors and nurses left.

Well, given that the accident caused zero immediate deaths, and maybe, MAYBE one statistical death over a background of thousands, I'd say the reaction of all of you was simply hysterical.

By the third day, you couldn't get gas at the gas station or cash from the ATM because all the SMART people had drained them before evacuating.

Nice. Are you feeling happy for yourself, knowing how greatly you inconvienced others - for nothing?

[Palladin]

No, I'm feeling happy for myself because I don't have cancer. The cancer rate went up exponentially in a 20 mile radius aound TMI 20 years after the accident.

Fortunately, I moved out of the area in 1981. Many of my friends who stayed behind have since died of cancer.

You should have seen the freakish farm animals born in York County during the years after TMI.

So much has been covered up.

[RightWhale]

The Civil Defense counters had a knob that could be turned to adjust the range.

[JEH_Boston]

A licensee working on the industrial coolers on top of the industrial building, standing on a ladder, fell off the ladder when OTSG relief valve opened. Licensee either broke or badly sprained his leg....and needed to wash his shorts.

[coloradan]

The cancer rate went up exponentially in a 20 mile radius aound TMI 20 years after the accident.

Source?

Many of my friends who stayed behind have since died of cancer.

That's funny, I know a lot of people who died of cancer too, and they weren't anywhere near TMI. Cancer didn't begin at TMI.

You should have seen the freakish farm animals born in York County during the years after TMI.

I wonder if you have any explanation for the burgeoning wild animal population around Chernobyl, which has, today, thousands of times more environmental radioactivity than TMI did or does?

[burzum]

Don't you know, it's been covered up! This allows him to make any statement without justification. And you questioning that the government hides information allows him to claim that *you* are detached from reality.

Really, saying the government has covered something up is always the perfect explanation for any conspiracy theory. You don't need anything beyond it other than a bold imagination!

The assassination of JFK? Government cover up.
Moon landings? Government cover up.
9/11? Government cover up.
TMI? Government cover up.
Missing socks in laundry? Government cover up.

[WWTraveler]

If they were wearing white suit, they just did not want to get dirty. If they had show up in yellow suits , then I would worry.

[WWTraveler]

I have heard that over 20 nuclear plants are on the "books". A lot well depend on the next Admin.

[Popman]

Was Al Gore seen leaving the site?