United States Nuclear Regulatory Commission - Protecting People and the Environment

Frequently Asked Questions About Security Assessments at Nuclear Power Plants

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What is the NRC doing about the possibility of a terrorist attack that could damage a nuclear power plant or spent fuel pool?

Response: After the terrorist attacks on September 11, 2001, the NRC first issued Advisories and then Orders that required nuclear power plant licensees to provide specific enhanced capabilities to respond to a terrorist attack. The NRC then began an accelerated security and engineering review based on the September 11 events. The review looked at what could possibly happen if terrorists used an aircraft to attack a nuclear power plant. Additionally, NRC reviews assessed the potential consequences of other types of terrorist attacks. The NRC analyzed what might happen as a result of such attacks and what other factors might affect the possibility or magnitude of a radiation release.

As part of this security review, the NRC conducted detailed engineering studies of a number of nuclear power plants. These studies assessed the capabilities of these plants to withstand deliberate attacks involving large commercial aircraft. The NRC studies included national experts from Department of Energy laboratories, who used state-of- the-art experiments, structural analyses, and fire analyses. The studies at the specific facilities confirmed that the plants are robust. In addition, the studies found that even in the unlikely event of a radiological release due to a terrorist attack, there would be time to implement the required offsite planning strategies already in place to protect public health and safety.

In a series of three phases (namely, Phase 1, Phase 2, and Phase 3), the NRC and the nuclear industry are analyzing the ability of nuclear power plants to withstand damage to or loss of large areas of the plant. This damage may be caused by a range of deliberate attacks that result in large fires and explosions. The assessments of spent fuel pools should be completed in early 2006. The identification of nuclear power plant mitigation strategies to protect the reactor core and containment should be completed in mid to late 2006.

In addition, the NRC is continuing to perform engineering studies and other assessments to determine the effectiveness of certain mitigation strategies.

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What actions has the NRC required nuclear power plants to implement to protect against deliberate aircraft attacks?

Response: In February 2002, the NRC ordered nuclear power plant licensees to develop specific plans and strategies to respond to a wide range of events, including the impact of an aircraft. Licensees have taken actions as a result of the NRC Advisories and Orders to mitigate the effects of a September 11-type aircraft attack. The NRC considers the list of specific actions taken to be information that potentially would benefit terrorists if released publically.

Even before these actions, nuclear power plants were designed to protect public health and safety. The plants achieved this through their robust containment buildings, redundant safety systems, highly trained operators and maintenance staff, stringent security plans, and armed security personnel. These plants are among the strongest and most difficult structures to break into in the country. They are designed to withstand extreme events, such as hurricanes, tornadoes, and earthquakes. Currently, the NRC and nuclear power plant licensees are performing site-specific safety and security assessments. These assessments are identifying ways each nuclear power plant can withstand a wide range of terrorist attacks.

The NRC has used defense-in-depth to define its safety philosophy at nuclear power plants. Defense-in-depth means there are multiple measures that could prevent an accident or lessen the effects of damage if a malfunction or accident occurs at a nuclear facility. The NRC's safety philosophy ensures that the public is protected and that emergency plans for areas surrounding a nuclear facility are well thought out and workable. In that regard, NRC-licensed nuclear power plants and other facilities have detailed, well coordinated, and tested emergency response plans. These plans work to reduce the impact on the public in the event of a radiation release.

The NRC regularly communicates with other federal agencies, including the Department of Homeland Security (DHS), the Federal Aviation Administration (FAA), and the Department of Defense (DOD), which have acted on specific occasions to protect airspace above nuclear power plants. The Aviation and Transportation Security Act of 2001 also provides additional protection against air attacks on all industrial facilities, both nuclear and non-nuclear, by strengthening aviation security.

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What is the Phase 1 effort?

Response: Phase 1 is part of a larger NRC effort to enhance the safety and security of the nation's nuclear power plants. The Phase 1 effort was initiated as part of a February 2002 NRC Order. The Order, among other things, required licensees to look at what might happen if a nuclear power plant lost large areas due to explosions or fire. The licensees then were required to identify – and later implement – strategies that would maintain or restore cooling for the reactor core, containment building, and spent fuel pool. The requirements listed in Section B.5.b of this Order directed licensees to identify "mitigative strategies" (meaning the measures licensees could take to reduce the potential consequences of a large fire or explosion) that could be implemented with resources already existing or "readily available." The NRC held inspections in 2002 and 2003 to identify whether licensees had implemented the required mitigative strategies.

These inspections, as well as additional studies, showed significant differences in the strategies implemented by the plants. As a result, the NRC developed additional mitigative strategy guidance as part of Phase 1. Among other things, the guidance was based on "lessons learned" from NRC engineering studies. In addition, the guidance included a list of "best practices" for mitigating losses of large areas of the plant. Each plant was requested to consider implementation of applicable additional strategies by August 31, 2005. The NRC inspected each plant in 2005 to review their implementation of any additional mitigative measures. The NRC is continuing to ensure licensees appropriately implement these measures.

What is Phase 2 of this effort?

Response: In Phase 2, the NRC independently looked at additional ways to protect the spent fuel pools at nuclear power plants. The NRC's plant-specific assessments identified both "readily available" and other resources that could be used to mitigate damage to spent fuel pools and the surrounding areas. The assessments considered damage that could have been caused by land, water, or air attacks. The assessment insights are being discussed and coordinated with the Department of Homeland Security as part of an overall plan to enhance the security of the nation's critical infrastructure.

Due to the sensitive nature of the information, the NRC is not releasing specific details about the assessments or what was found.

What is Phase 3 of this effort?

Response: In Phase 3, each nuclear power plant licensee identified ways to improve its ability to protect the reactor core and containment from a terrorist attack. This was done by identifying both "readily available" and other resources that could be used to mitigate loss of large areas of the plant due to fires and explosions. In addition, the NRC independently assessed the plant and audited the licensee's effort to identify additional mitigation strategies. These efforts also are being coordinated with the Department of Homeland Security.

Due to the sensitive nature of the information, the NRC is not releasing specific details about the assessments or what was found.

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Do the studies consider all reasonable terrorist threats to a nuclear power plant or do they only consider aircraft attacks?

Response: The studies consider a wide variety of possible terrorist attacks and take into account "lessons learned" from earlier NRC studies.

Did NRC conduct these studies at each nuclear power plant site or did NRC do a generic analysis of representative nuclear power plants?

Response: The NRC initially conducted detailed engineering studies on a number of representative plants that looked at damage that could be caused to plants by large commercial aircraft. These studies found that there were enough differences between the plants that site-specific studies would be worthwhile. The NRC Phase 1, 2, and 3 assessments are site-specific. They look at how potential damage to each plant might affect the reactor’s core, containment, and spent fuel pool and identify mitigating strategies for losses of large areas of the plant.

What is the schedule for performing the Phase 1, Phase 2, and Phase 3 assessments?

Response: During 2006, the NRC expects to complete the Phase 1, 2, and 3 assessments. Additionally, the NRC expects to complete the directions on what actions it wants nuclear power plants to take based on the results of these assessments.

How long do the assessments take?

Response: In general, each of the initial, detailed engineering analyses performed took about 2 years to complete. The site-specific assessments for Phases 1 and 2 that followed took about two months each to complete. The site-specific security and safety assessments currently ongoing in Phase 3 are expected to be completed by mid-2006. Each assessment takes about four staff weeks of effort for the NRC and many hundreds of hours for licensees.

What are the qualifications of the personnel who have developed the methodologies or are conducting these assessments?

Response: The analyses and assessments were conducted by highly trained experts in structural engineering, fire protection engineering, nuclear power plant operations, engineering, health physics, emergency preparedness, and risk assessment.

Are the assessment results going to be made public?

Response: The NRC is committed to openness, but must also protect public health, safety, and security. The NRC does not discuss information in public that could assist terrorists and make nuclear power plants less secure. This includes site-specific security and safety assessment results. However, the NRC expects to provide the public with general information relating to the outcome of the assessments, and will share details of the assessments with appropriate stakeholders, such as Congress and state, local, and federal officials.

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How can the public be assured that nuclear power plants are safe from terrorists if the NRC won't share the information with the public?

Response: The NRC has to perform a difficult balancing act since it desires to be open in its communications but needs to limit the type of information it releases to the public related to the security of nuclear power plants. The NRC does not publically release information that could potentially assist terrorists. However, the NRC has shared general information with the public to help people understand security actions being taken. Elected officials such as state governors and members of Congress are given briefings of sensitive unclassified or classified information, as appropriate. In addition, the NRC coordinates with many security related organizations within the Federal Government via classified briefings.

What information has the NRC released to the public about measures taken to secure nuclear power plants against potential terrorist attacks?

Response: The NRC issued a number of unclassified documents to the public to communicate the extra effort that has gone into nuclear security since 9/11. Some examples include the publication, "Protecting Our Nation," and a fact sheet titled "Safety and Security Improvements at Nuclear Plants." Both of these are publicly available. These publications provide an overview of the security actions the NRC has taken, and is taking, since 9/11. In addition, the NRC has publically released general information from the detailed engineering studies performed to assess security-related threats involving large commercial aircraft.

What actions have other federal agencies taken to reduce the potential for aircraft attack?

Response: The NRC continues to work with other federal agencies to assure consistency and effectiveness in thwarting a potential aircraft attack on a nuclear power plant. The NRC has worked with the Transportation Security Administration (TSA) and the FAA to develop guidance for general aviation pilots flying near nuclear power plants. The TSA has initiated a number of other programs to reduce the likelihood an aircraft could attack any type of facility in the U.S. Some of these include:

  • Criminal history checks on flight crew members
  • Reinforced cockpit doors
  • Checking of passenger lists against "no-fly" lists
  • Restrictions on cargo
  • Random inspections
  • Increased number of air marshals
  • Screening of passengers and baggage
  • Federal Flight Deck Officer Program
  • Controls on foreign airlines operating to and from the US
  • Controls on domestic and foreign cargo carriers
  • Additional requirements for charter aircraft

Has the Department of Homeland Security (DHS) been involved in these nuclear power plant assessments and has this information been shared with the FBI and other security agencies?

Response: Yes, the insights and results of these efforts are being shared and coordinated with DHS to further enhance the overall security of the nation's critical infrastructure. The NRC routinely interacts with the appropriate federal agencies regarding nuclear power plant security including DHS, FBI, FAA, the Coast Guard, and others.

Does the NRC consult with the CIA, FBI and other federal agencies when assessing security measures?

Response: The NRC routinely interacts with appropriate federal agencies regarding nuclear power plant security including: DHS, Federal Bureau of Investigation (FBI), Central Intelligence Agency (CIA), Federal Aviation Administration (FAA), Department of Energy, and many others. The NRC evaluates the adequacy of the security measures and coordinates these evaluations with appropriate Federal and State agencies through activities such as Force-on-Force inspections and emergency preparedness exercises.

Especially as related to spent fuel pools, why didn't the NRC work with the National Academy of Science during the assessments?

Response: Congress asked the National Academy of Science (NAS) to independently assess the nation's nuclear power plant spent fuel pools’ vulnerability to an aircraft attack. The NRC worked with the NAS to develop a public version of the report. The NRC believes this is very important. The NRC is giving the results and recommendations of the study serious consideration and is continuing to work with the NAS on this subject. In March 2005, the NRC provided Congress with a report on actions the NRC has taken to ensure the safety and security of spent nuclear fuel storage. The report also responds to the recommendations contained in the NAS study. The NRC's Phase 1 and Phase 2 efforts address a number of issues raised by the NAS study.

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Page Last Reviewed/Updated Thursday, October 31, 2013