Near-Miss Accident at Nine Mile Point Nuclear Reactor to be Cited by NRC

[kristopher]

Following the press release are two links, one to the NRCs finding, and the other to a powerpoint slideshow that will walk you through the event.

Near-Miss Accident at Nine Mile Point to be Cited by NRC

Media Advisory

September 25, 2013

Contact: Tim Judson, Nuclear Information and Resource Service [phone]
David Lochbaum, Union of Concerned Scientists [phone]


Oswego, NY Nuclear Plant to be Cited for Safety Violation
Near-Miss Accident in April Due to Operator Errors, “Inadequate Procedures”
Agency Cites Inadequate Time to Evacuate Local Residents


Alliance for a Green Economy and Nuclear Information and Resource Service received notice that the U.S. Nuclear Regulatory Commission is preparing to cite the operator of the Nine Mile Point nuclear station for safety violations in relation to a near-miss accident on April 16, 2013. The event was loss of power to shutdown cooling systems, during which the reactor was within two hours from boiling and releasing radioactive steam into the reactor building.


Details: Constellation operators lost all power to the shutdown cooling systems for over 30 minutes, at the beginning of the refueling outage. Operators were preparing to defuel the reactor, and had opened containment seals and disconnected steam vent to the reactor vessel, effectively removing all barriers to a radiation release and disabling one of the essential backup cooling systems. Constellation had not removed the reactor vessel head, and all of the fuel was still in the reactor.

The incident happened just two days after shutdown for refueling, so the fuel in the reactor was still at its hottest, and the water in the vessel heated up by 27 degrees in a half-hour. NRC estimates the reactor would have begun boiling within 110 minutes -- or less than 80 minutes from when Constellation workers managed to get the pumps working again – thereby spewing steam into the building that houses the reactor and many of its key safety systems.

NRC says it would have taken about 9 hours before the water boiled down to where the fuel was exposed, which could have led to a meltdown. (NRC letter, page A-2)

The NRC notice also cites a major concern over the lack of time to evacuate the public in the vicinity, due to the fast-breaking nature of the radiation release that could have occurred. With the reactor vessel and containment both open, there were no barriers to the release of radiation, and local residents might not have gotten enough notice to leave the area before they were exposed.

http://allianceforagreeneconomy.org/content/near-miss-accident-nine-mile-point-be-cited-nrc

[Demeter]

1. again?

didn't they shut down 9 mile island for good?

[kristopher]

2. Some of the corporations seem to prefer running them until they break down.

Screw the consequences, the public will pick up the tab for damages.

[Sirveri]

4. I think you're thinking of Three Mile.

I think that was unit 2 that melted there, though they're still running unit 1 last I heard.

[Demeter]

5. My mistake, you are correct

[madokie]

3. Its only a matter of time until we have a serious nuclear accident here in the USA

since many of our nukes are sited near large metropolitan areas it could be devastating when it does happen

[FBaggins]

6. It's amazing what nonsense will get labeled as a "near miss" among the usual suspects, eh?

The likelyhood of core damage or significant release plunged to a low of about one-in-one-million-years. This is based on the liklihood that they would be unable to restore SDC (two other pumps available with simple manual action) and also be unable to add water to offset any boil-off (incredbily easy from a number of systems) for nine hours.

With "near misses" like that... lol.

The incident happened just two days after shutdown for refueling, so the fuel in the reactor was still at its hottest

Painful to see a "scientist" screw up so badly on the difference between temperature and heat (an error a highschool physics student should catch)... but whatever. It certainly was nowhere near "its hottest". The core was obviously at atmospheric pressure and well below the boiling point.

effectively removing all barriers to a radiation release

All barriers apart from the water? Just like a spent fuel pool? Big deal. They know how to pump water.

thereby spewing steam into the building that houses the reactor and many of its key safety systems.

Yep... steam. Apart from a tiny amount of tritium... it wouldn't be radioactive steam since the core temperature wouldn't rise above the boiling point of water.

It's a screwup/accident... but it's hardly a "near miss"

[PamW]

7. I concur; it's NONSENSE

FBaggins,

Unfortunately, this is what we get when we have people that don't know the technology, and refuse to learn.

Someone can make any fool claim they want; and if people don't know the technology, they can't properly evaluate the claim; and run off like a bunch of scared lemmings.

It's like take-off in a commercial airliner in a light snow. The plane is de-iced before take-off; but during the few minutes it takes the plane to taxi from the de-icing station to the runway, the wings get a light dusting of snow.

That light dust of snow is INCONSEQUENTIAL and is blown off in the first few seconds of the take-off run. However, the people who don't know aerodynamics, and have heard that snow and ice on the wings is bad; but can't quantitatively evaluate it; can go nuts about a light dust of snow.

If you don't have the mental horsepower to understand the science; then leave the science up to the people who are smart enough to do science.

PamW