Major Tsunami Events

US Nuclear Agency Rethinking Major Safety Requirements After Japan's Disaster

Martin Virgilio, NRC's deputy executive director for reactor and preparedness programs, said the commission is reanalyzing its safety requirements, both voluntary and mandatory, for combating the loss of electricity to plants and ensuring key safety equipment is operable and accessible during an emergency.

"What we once thought was not necessary for adequate protection, may in fact become necessary for adequate protection as a result of our study," Virgilio on Thursday told the Advisory Committee on Reactor Safeguards, a part-time panel of federal workers that has the authority to question NRC's decisions on licensing and reactor safety.

An NRC task force made up of senior officials and staff is slated to issue a final report on its findings on July 12, with a public release of its recommendations on July 19.

Although the task force has not found any indication U.S. reactors are unsafe, the group has revealed that nuclear plant operators rely on voluntary initiatives to safeguard reactors from catastrophic events like those that befell Japan's Fukushima Daiichi plant and that industry is not always following those guidelines.

For example, inspections earlier this month found operators are not consistently implementing voluntary "severe accident management guidelines," steps to be taken after a reactor's fuel has been damaged during an emergency and the operator is attempting to limit radioactive releases. The guidelines, or SAMGs, were implemented in the 1990s and do not fall under NRC's oversight program.

NRC inspectors found that safety equipment, mainly pumps, were found to be inoperable, missing or inaccessible because of plant modifications. NRC Chairman Gregory Jaczko and Commissioner George Apostolakis earlier this month pointed out the weakness of relying on voluntary safety standards to address rare but extreme threats to nuclear plants ( ClimateWire , June 16).

"We've been somewhat inconsistent as a function of time and also issue-specific around whether [some rules are] voluntary or whether [they are] brought into the regulations," Virgilio said. "That's one of our key findings of the task force. Where we go with that, I think it's a little bit too soon to tell."

The task force is also looking into safety assumptions underlying requirements for plants to combat loss of on-site and off-site power. Those rules, Virgilio said, do not consider major events that would wipe out both sources of electricity, like the earthquake and tsunami that struck Japan. The rules also assume that AC power at the plants would be operable within hours, he said.

saendy: Groundbreaking Tsunami and Flood Shelter System is ...

Groundbreaking Tsunami and Flood Shelter System is Unveiled, Receives US Patent

A US inventor unveiled today a revolutionary shelter system that could become the first line of defense for governments against two of the most devastating natural events on the planet, tsunamis and major floods. This novel shelter, capable of floating, could prove to be an invaluable contribution toward emergency preparedness worldwide.

San Juan, PR (PRWEB) July 27, 2010

A US inventor unveiled today a revolutionary shelter system that could become the first line of defense for governments against two of the most devastating natural events on the planet, tsunamis and major floods. This novel shelter, capable of floating, could prove to be an invaluable contribution toward emergency preparedness worldwide. 

"After watching the devastation and aftermath of the 2004 Indonesian tsunami and hurricane Katrina events, I committed myself to designing a preparedness tool capable of offering an effective level of protection against such catastrophic events" said Miguel A. Serrano, a land development consultant from Puerto Rico. "The end result is a revolutionary shelter system that is both highly effective, and cost efficient", he added.

This new system, for which a US patent has been allowed, is called the STATIM (Storm, Tornado And Tsunami Interconnected Modules) Shelter System. In essence, it is an enclosable hull comprised of a series of pre-cast concrete modules, similar to large diameter concrete drainage pipes. Once assembled via gasketed joints, and a post-tensioned cables technique, it provides a water-tight environment with positive buoyancy and self-righting capability. Inside, the shelters are equipped with secure seating arrangements for as many as 50 occupants, ventilation, and various options of survival gear and supplies capable of sustaining the occupants during and after the actual event, until available rescue resources can assist. The STATIM Shelter can be considered the equivalent of an "inland" life boat.

"Concrete is a low cost material readily available worldwide, doesn't require skilled labor, and has a long life cycle. Additionally, it is strong and provides the necessary mass and inertia for the shelters to safely handle the initial event forces.” explains Serrano. “The modular concept and post-tensioning technique allows for off-site mass manufacturing, ease of transportability, and rapid final assembly once the modules arrive to the final installation sites”.

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