Virginia earthquake caused massive nuclear storage casks to move - quake's motion may have exceeded nuclear plant's design

[Emily]

http://latimesblogs.latimes.com/nationnow/2011/08/virginia-quakes-motion-may-have-exceeded-nuclear-plants-design.html

Virginia quake's motion may have exceeded nuclear plant's design
August 29, 2011 | 4:05 pm

More federal inspectors are en route to Virginia's North Anna nuclear power station after early data indicated the plant may have experienced more shaking than it was designed to withstand during last week's 5.8 earthquake....

http://en.wikipedia.org/wiki/North_Anna_Nuclear_Generating_Station

 

[Emily]

Re: Virginia quake's motion may have exceeded nuclear plant's design

Re: Virginia quake's motion may have exceeded nuclear plant's design

No radiation release or other hazards reported, but what would a larger earthquake do if casks are not secured to the pads?

http://www2.timesdispatch.com/business/2011/aug/31/2/earthquake-caused-massive-nuclear-storage-casks-to-ar-1277791/

Earthquake caused massive nuclear storage casks to move
North Anna

The shifting of spent-fuel casks at Dominion Virginia Power's North Anna nuclear power plant last week was the first caused by an earthquake.

By: PETER BACQU? | Richmond Times-Dispatch
Published: August 31, 2011
Updated: August 31, 2011 - 11:30 PM


Last week's central Virginia earthquake caused 25 spent-fuel storage casks ? each weighing 115 tons ? to move on their concrete pad at Dominion Virginia Power's North Anna nuclear power plant....

 

[Emily]

Re: Virginia earthquake caused massive nuclear storage casks to move - quake's motion may have exceeded nuclear plant's design

According to a preliminary NRC review, the North Anna reactors are among 27 in the eastern and central U.S. that might need upgrades because those plants are more likely to get hit with an earthquake larger than the one they were designed to withstand.

http://www.whsv.com/news/headlines/129269648.html?ref=648

Posted: 5:37 PM Sep 5, 2011
Dominion: North Anna Reactors Won't Restart Until Safety Assured
LOUISA, Va. (AP)
[snip]
Based on preliminary data, the plant did exceed some seismic measures for its site design but was still within safety margins, Stoddard said.
[snip]
Within seconds of the afternoon tremor, the plant automatically shut down. At that time, the facility lost off-site power and control rods dropped into the reactor core and stopped the nuclear chain reaction, shutting down the reactor. Officials are unsure whether the rods fell due to the shaking or loss of power, but the rods dropping is not unusual and can happen even during something as simple as a blown fuse.....

 

[Emily]

Re: Virginia earthquake caused massive nuclear storage casks to move - quake's motion may have exceeded nuclear plant's design

http://www.bloomberg.com/news/2011-09-14/old-equipment-may-skew-dominion-s-seismic-data-scientist-says.html

Old Equipment May Skew Dominion?s Quake Data, Scientist Says
By Brian Wingfield - Sep 14, 2011 2:59 PM PT

Here's an abstract from a study done in the area of the Virginia EQ after the power plant was built:

http://bulletin.geoscienceworld.org/cgi/content/abstract/96/12/1580

GSA Bulletin; December 1985; v. 96; no. 12; p. 1580-1584; DOI: 10.1130/0016-7606(1985)96<1580:SSRGAG>2.0.CO;2
? 1985 Geological Society of America

Seismicity, seismic reflection, gravity, and geology of the central Virginia seismic zone: Part 3. Gravity
M. R. KELLER1, E. S. ROBINSON1 and LYNN GLOVER, III1

1 Department of Geological Sciences, Virginia Polytechnic Institute and State University, Blacksburg, Virginia 24061

Bouguer gravity anomalies at 1,870 locations on the central Piedmont of Virginia from 37?37'N to 37?52'N and 77?44'W to 78?23'W display patterns of variation produced by upper-crustal density contrasts and thickening of the crust in a west-northwest direction.
[snip]
Gravity anomalies are consistent with the existence of a major thrust fault, at depths between 9 km and 16 km, that probably separates Grenville Basement rocks from younger, Catoctin/Lynchburg rocks. These anomalies confirm that the slight eastward dip of this thrust fault beneath the western part of the area increases significantly east of 78?05'W.

The Virginia quake was not far north of that study area above:

Magnitude 5.8 - VIRGINIA
2011 August 23 17:51:03 UTC
Date-Time Tuesday, August 23, 2011 at 17:51:03 UTC
Tuesday, August 23, 2011 at 01:51:03 PM at epicenter
Location 37.875?N, 77.908?W
Depth 6 km (3.7 miles)

 

[Emily]

U.S. Justice Department Memo says utility, U.S. covered up fault line's existence North Anna[

U.S. Justice Department Memo says utility, U.S. covered up fault line's existence North Anna[

http://www2.timesdispatch.com/news/news/2011/nov/06/tdmain01-utility-and-federal-regulators-covered-up-ar-1438362/

Memo says utility, U.S. covered up fault line's existence
North Anna

Credit: JOE MAHONEY/TIMES-DISPATCH

Dominion?s two 980-megawatt nuclear reactors at North Anna have been shut down since Aug. 23, when a magnitude-5.8 earthquake hit central Virginia.

By: PETER BACQU? | Richmond Times-Dispatch
Published: November 06, 2011

Dominion Virginia Power and federal nuclear regulatory staff members covered up knowledge of geologic faulting at the North Anna Power Station site in 1973, according to a U.S. Justice Department memo...

http://fredericksburg.com/News/FLS/2011/112011/11022011/662362

Decision on North Anna may come soon
NRC staff provides an update on North Anna's restart review
Date published: 11/2/2011

By RUSTY DENNEN
[snip]
Among those in the crowd were a group of about 40 pro-nuclear power employees of Areva North America, who were bused in for the occasion from Lynchburg....