WASHINGTON, Sept 1, 2011 (AFP) - A rare earthquake on America's east coast last month caused half the radioactive waste containers at a nuclear plant to move several centimeters but they were not damaged, operators said Thursday.
Of the 53 giant containers storing waste at North Anna power station in central Virginia near the epicenter of the August 23 quake, 27 were displaced by seismic tremors, according to Dominion, the power company that runs the site.
The movements ranged between 2.5-11.4 centimeters, spokesman Richard Zuercher told AFP.
North Anna is located 150 kilometers (90 miles) west of Washington and the 5.8 magnitude quake was centered 3.7 miles (six kilometers) under the Virginia town of Mineral, 134 kilometers southwest of the US capital.
The rare quake's force was felt as far south as Alabama and as far north as Boston.
North Anna's containers store depleted uranium dioxide but helium gas is added as a safety measure and the latter is designed to escape in the event of a leakage, allowing the alarm bell to be raised.
"We tested it, there is no trace of helium which is the gas they are filled with. The containers are intact," Zuercher said, noting that North Anna could withstand such a quake, contrary to reports at the time that it may not.
Zuercher said the surprise seismic disturbance caused only "superficial cracks" in some office buildings and stressed that North Anna was capable of withstanding a 6.2 magnitude quake.