Nuclear Power Plant Security and 
Vulnerabilities 
Mark Holt 
Specialist in Energy Policy 
Anthony Andrews 
Specialist in Energy and Defense Policy 
August 23, 2010 
Congressional Research Service
7-5700 
www.crs.gov 
RL34331 
CRS Report for Congress
P
  repared for Members and Committees of Congress        
Nuclear Power Plant Security and Vulnerabilities 
 
Summary 
The physical security of nuclear power plants and their vulnerability to deliberate acts of 
terrorism was elevated to a national security concern following the attacks of September 11, 
2001. Since the attacks, Congress has repeatedly focused oversight and legislative attention on 
nuclear power plant security requirements established and enforced by the Nuclear Regulatory 
Commission (NRC). 
The Energy Policy Act of 2005 (EPACT05, P.L. 109-58) imposed specific criteria for NRC to 
consider in revising the “Design Basis Threat” (DBT), which specifies the maximum severity of 
potential attacks that a nuclear plant’s security force must be capable of repelling. In response to 
the legislative mandate, NRC revised the DBT (10 C.F.R. Part 73.1) on April 18, 2007. Among 
other changes, the revisions expanded the assumed capabilities of adversaries to operate as one or 
more teams and attack from multiple entry points. 
To strengthen nuclear plant security inspections, EPACT05 required NRC to conduct “force-on-
force” security exercises at nuclear power plants at least once every three years. In these 
exercises, a mock adversary force from outside a nuclear plant attempts to penetrate the plant’s 
vital area and simulate damage to a “target set” of key safety components. From the start of the 
program through 2009, 112 force-on-force inspections were conducted, with each inspection 
typically including three mock attacks by the adversary force. During the 112 inspections, eight 
mock attacks resulted in the simulated destruction of complete target sets, indicating inadequate 
protection against the DBT, and additional security measures were promptly implemented, 
according to NRC. 
EPACT05 also included provisions for fingerprinting and criminal background checks of security 
personnel, their use of firearms, and the unauthorized introduction of dangerous weapons. The 
designation of facilities subject to enforcement of penalties for sabotage was expanded to include 
waste treatment and disposal facilities. 
Nuclear power plant vulnerability to deliberate aircraft crashes has been a continuing issue. After 
much consideration, NRC published final rules on June 12, 2009, to require all new nuclear 
power plants to incorporate design features that would ensure that, in the event of a crash by a 
large commercial aircraft, the reactor core would remain cooled or the reactor containment would 
remain intact, and radioactive releases would not occur from spent fuel storage pools. 
NRC rejected proposals that existing reactors also be required to protect against aircraft crashes, 
such as by adding large external steel barriers, deciding that other mitigation measures already 
required by NRC for all reactors were sufficient. In 2002, NRC ordered all nuclear power plants 
to develop strategies to mitigate the effects of large fires and explosions that could result from 
aircraft crashes or other causes. NRC published a broad final rule on nuclear reactor security 
March 27, 2009, including fire mitigation strategies and requirements that reactors establish 
procedures for responding to specific aircraft threats. 
Other ongoing nuclear plant security issues include the vulnerability of spent fuel pools, which 
hold highly radioactive nuclear fuel after its removal from the reactor, standards for nuclear plant 
security personnel, and nuclear plant emergency planning. NRC’s March 2009 security 
regulations addressed some of those concerns and included a number of other security 
enhancements. 
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Nuclear Power Plant Security and Vulnerabilities 
 
Contents 
Overview of Reactor Security ..................................................................................................... 1 
Design Basis Threat .................................................................................................................... 2 
Large Aircraft Crashes ................................................................................................................ 4 
Spent Fuel Storage ...................................................................................................................... 6 
Force-on-Force Exercises............................................................................................................ 7 
Emergency Response .................................................................................................................. 9 
Security Personnel and Other Issues ............................................................................................ 9 
 
Contacts 
Author Contact Information ...................................................................................................... 11 
 
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Nuclear Power Plant Security and Vulnerabilities 
 
Overview of Reactor Security 
Physical security at nuclear power plants involves the threat of radiological sabotage—a 
deliberate act against a plant that could directly or indirectly endanger public health and safety 
through exposure to radiation. The Nuclear Regulatory Commission (NRC) establishes security 
requirements at U.S. commercial nuclear power plants based on its assessment of plant 
vulnerabilities to, and the consequences of, potential attacks. The stringency of NRC’s security 
requirements and its enforcement program have been a significant congressional issue, especially 
since the September 11, 2001, terrorist attacks on the United States. 
While NRC establishes security requirements within the boundaries of commercial nuclear sites, 
the Department of Homeland Security (DHS) has broad responsibility for coordinating 
government-wide efforts to prevent and respond to terrorist attacks, including attacks on nuclear 
power plants. DHS works with NRC and other agencies to protect nuclear facilities and other 
critical infrastructure.1 
Nuclear plant security measures are designed to protect three primary areas of vulnerability: 
controls on the nuclear chain reaction, cooling systems that prevent hot nuclear fuel from melting 
even after the chain reaction has stopped, and storage facilities for highly radioactive spent 
nuclear fuel. U.S. plants are designed and built to prevent dispersal of radioactivity, in the event 
of an accident, by surrounding the reactor in a steel-reinforced concrete containment structure. 
NRC requires commercial nuclear power plants to have a series of physical barriers and a trained 
security force, under regulations already in place prior to the 9/11 attacks (10 C.F.R. 73—Physical 
Protection of Plants and Materials). The plant sites are divided into three zones: an “owner-
controlled” buffer region, a “protected area,” and a “vital area.” Access to the protected area is 
restricted to a portion of plant employees and monitored visitors, with stringent access barriers. 
The vital area is further restricted, with additional barriers and access requirements. The security 
force must comply with NRC requirements on pre-hiring investigations and training.2 
A fundamental concept in NRC’s physical security requirements is the design basis threat (DBT), 
which establishes the severity of the potential attacks that a nuclear plant’s security force must be 
capable of repelling. The DBT includes such characteristics as the number of attackers, their 
training, and the weapons and tactics they could use. Specific details are classified. Critics of 
nuclear plant security have contended that the DBT should be strengthened to account for 
potentially larger and more sophisticated terrorist attacks. 
Reactor vulnerability to deliberate aircraft crashes has also been a major concern since 9/11. Most 
existing nuclear power plants were not specifically designed to withstand crashes from large 
jetliners, although analyses differ as to the damage that could result. NRC has determined that 
commercial aircraft crashes are beyond the DBT but published regulations in June 2009 to require 
that new reactor designs be able to withstand such crashes without releasing radioactivity. 
Nuclear power critics have called for retrofits of existing reactors as well. 
                                                             
1 Homeland Security Presidential Directive 7: Critical Infrastructure Identification, Prioritization, and Protection, 
December 17, 2003, http://www.dhs.gov/xabout/laws/gc_1214597989952.shtm#1. 
2 General NRC requirements for nuclear power plant security can be found in 10 C.F.R. 73.55. 
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Since the 9/11 attacks, NRC and Congress have taken action to increase nuclear power plant 
security. NRC issued a series of security measures beginning in 2002, including a strengthening 
of the DBT and establishing the Office of Nuclear Security and Incident Response (NSIR). The 
office centralizes security oversight of all NRC-regulated facilities, coordinates with law 
enforcement and intelligence agencies, and handles emergency planning activities. In 2004, NRC 
implemented a program to conduct “force on force” security exercises overseen by NSIR at each 
nuclear power plant at least every three years. The Energy Policy Act of 2005 (P.L. 109-58) 
required NRC to further strengthen the DBT, codified the force-on-force program, and established 
a variety of additional nuclear plant security measures. In March 2009, NRC published a series of 
security regulations that require power plants to prepare cyber security plans, develop strategies 
for dealing with the effects of aircraft crashes, strengthen access controls, improve training for 
security personnel, and take other new security measures. 
Design Basis Threat 
The design basis threat describes general characteristics of adversaries that nuclear plants and 
nuclear fuel cycle facilities must defend against to prevent radiological sabotage and theft of 
strategic special nuclear material. NRC licensees use the DBT as the basis for implementing 
defensive strategies at specific nuclear plant sites through security plans, safeguards contingency 
plans, and guard training and qualification plans. 
General requirements for the DBT are prescribed in NRC regulations,3 while specific attributes of 
potential attackers, such as their weapons and ammunition, are contained in classified adversary 
characteristics documents (ACDs). 
Fundamental policies on nuclear plant security threats date back to the Cold War. In 1967, the 
Atomic Energy Commission (AEC) instituted a rule that nuclear plants are not required to protect 
against an attack directed by an “enemy of the United States.”4 That so-called “Enemy of the 
State Rule” specifies that nuclear power plants are 
not required to provide for design features or other measures for the specific purpose of 
protection against the effects of (a) attacks and destructive acts, including sabotage, directed 
against the facility by an enemy of the United States, whether a foreign government or other 
person, or (b) use or deployment of weapons incident to U.S. defense activities.5 
The Nuclear Regulatory Commission (NRC), the AEC’s successor regulatory agency, says that 
the rule “was primarily intended to make clear that privately-owned nuclear facilities were not 
responsible for defending against attacks that typically could only be carried out by foreign 
military organizations.”6 NRC’s initial DBT, established in the late 1970s, was intended to be 
consistent with the enemy of the state rule, which remains in effect. 
                                                             
3 10 C.F.R. § 73.1. 
4 It was feared that Cuba might launch an attack on Florida reactors. Government Accountability Office, Nuclear 
Power Plants—Efforts Made to Upgrade Security, but the Nuclear Regulatory Commission’s Design Basis Threat 
Process Should Be Improved (GAO-06-388), March 2006, p. 2. Regulations at 10 CFR 50.13. 
5 10 C.F.R. § 50.13. Attacks and destructive acts by enemies of the United States; and defense activities. 
6 Nuclear Regulatory Commission, “Design Basis Threat,” 72 Federal Register 12714, March 19, 2007. 
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However, the 9/11 attacks drew greater attention to the potential severity of credible terrorist 
threats. Following the attacks, NRC evaluated the extent to which nuclear plant security forces 
should be able to defend against such threats, and ordered a strengthening of the DBT, along with 
other security measures, on April 29, 2003. That order changed the DBT to “represent the largest 
reasonable threat against which a regulated private guard force should be expected to defend 
under existing law,” according to the NRC announcement.7 
In the Energy Policy Act of 2005 (EPACT05), Congress imposed a statutory requirement on the 
NRC to initiate rulemaking for revising the design basis threat.8 EPACT05 required NRC to 
consider 12 factors in revising the DBT, such as an assessment of various terrorist threats, sizable 
explosive devices and modern weapons, attacks by persons with sophisticated knowledge of 
facility operations, and attacks on spent fuel shipments. 
NRC approved its final rule amending the DBT (10 C.F.R. Part 73.1) on January 29, 2007, 
effective April 18, 2007.9 Although specific details of the revised DBT were not released to the 
public, in general the final rule 
•  clarifies that physical protection systems are required to protect against diversion 
and theft of fissile material; 
•  expands the assumed capabilities of adversaries to operate as one or more teams 
and attack from multiple entry points; 
•  assumes that adversaries are willing to kill or be killed and are knowledgeable 
about specific target selection; 
•  expands the scope of vehicles that licensees must defend against to include water 
vehicles and land vehicles beyond four-wheel-drive type; 
•  revises the threat posed by an insider to be more flexible in scope; and 
•  adds a new mode of attack from adversaries coordinating a vehicle bomb assault 
with another external assault. 
The DBT final rule excluded aircraft attacks as beyond the reasonable responsibility of a private 
security force, a decision that raised considerable controversy. In approving the rule, NRC 
rejected a petition from the Union of Concerned Scientists to require that nuclear plants be 
surrounded by aircraft barriers made of steel beams and cables (the so-called “beamhenge” 
concept). Critics of NRC’s final rule charged that deliberate aircraft crashes were a highly 
plausible mode of attack, given the events of 9/11. However, NRC contended that power plants 
were already required to mitigate the effects of aircraft crashes and that “active protection against 
airborne threats is addressed by other federal organizations, including the military.”10 Additional 
NRC action on aircraft threats is discussed in the next section. 
                                                             
7 Federal Register, May 7, 2003 (vol. 68, no. 88). NRC, All Operating Power Reactor Licensees; Order Modifying 
Licenses. 
8 P.L. 109-58, Title VI, Subtitle D—Nuclear Security (Secs. 651-657). Sec. 651 adds Atomic Energy Act Sec. 170E. 
Design Basis Threat Rulemaking. 
9 Federal Register, March 19, 2007 (vol. 72, no. 52), NRC, Design Basis Threat, Final Rule, pp. 12705-12727. 
10 NRC, “NRC Approves Final Rule Amending Security Requirements,” News Release No. 07-012, January 29, 2007. 
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NRC Commissioners in January 2009 rejected a proposal by the NRC staff to strengthen the 
classified portion of the DBT to include additional capabilities by potential attackers, according to 
news reports. The staff proposal lost in a 2-2 vote, with one commissioner position vacant. In an 
interview afterward, NRC Chairman Dale Klein said the vote could be reconsidered after 
completion of an ongoing interagency study.11 Critics contend that the DBT excludes major types 
of weapons used by terrorists, such as rocket-propelled grenades, and is generally not based on 
the maximum credible threat identified by the intelligence community.12 
Critics of NRC’s security regulations also have pointed out that licensees are required to employ 
only a minimum of 10 security personnel on duty per plant, which they argue is not enough for 
the job.13 Nuclear spokespersons have responded that the actual security force for the nation’s 65 
nuclear plant sites numbers more than 5,000, an average of about 75 per site (covering multiple 
shifts). The industry also points out that nuclear plants all have integrated communications and 
emergency response plans that include local, state, and federal security forces. The integrated 
response by outside security forces is intended to handle attacks that might overwhelm an 
individual plant’s security force.14 
Large Aircraft Crashes 
Nuclear power plants were designed to withstand hurricanes, earthquakes, and other extreme 
events. But deliberate attacks by large airliners loaded with fuel, such as those that crashed into 
the World Trade Center and Pentagon, were not analyzed when design requirements for today’s 
reactors were determined.15 Concern about aircraft crashes was intensified by a taped interview 
shown September 10, 2002, on the Arab TV station al-Jazeera, which contained a statement that 
Al Qaeda initially planned to include a nuclear plant in its list of 2001 attack sites. 
In light of the possibility that an air attack might penetrate the containment structure of a nuclear 
plant or a spent fuel storage facility, some interest groups have suggested that such an event could 
be followed by a meltdown or spent fuel fire and widespread radiation exposure. Nuclear industry 
spokespersons have countered by pointing out that relatively small, low-lying nuclear power 
plants are difficult targets for attack, and have argued that penetration of the containment is 
unlikely, and that even if such penetration occurred it probably would not reach the reactor vessel. 
They suggest that a sustained fire, such as that which melted the steel support structures in the 
World Trade Center buildings, would be impossible unless an attacking plane penetrated the 
containment completely, including its fuel-bearing wings. According to former NRC Chairman 
Nils Diaz, NRC studies, which have not been released, “confirm that the likelihood of both 
                                                             
11 Jeff Beattie, “NRC Chairman Questions Case for Tougher DBT,” Energy Daily, February 17, 2009, p. 1. 
12 Edwin S. Lyman, “Security Since September 11th,” Nuclear Engineering International, March 2010, pp. 14-19. 
13 10 C.F.R. 73.55 (k)(5)(ii) states: “The number of armed responders shall not be less than ten (10).” The previous 
requirement, in 10 C.F.R. 73.55 (h)(3), stated: “The total number of guards, and armed, trained personnel immediately 
available at the facility to fulfill these response requirements shall nominally be ten (10), unless specifically required 
otherwise on a case by case basis by the Commission; however, this number may not be reduced to less than five (5) 
guards.” The change was made in NRC final regulations published in March 2009, op. cit. 
14 Doug Walters, “Security Since March,” Nuclear Engineering International, May 2010. 
15 Meserve, Richard A., NRC Chairman, “Research: Strengthening the Foundation of the Nuclear Industry,” Speech to 
Nuclear Safety Research Conference, October 29, 2002. 
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damaging the reactor core and releasing radioactivity that could affect public health and safety is 
low.”16 
NRC proposed in October 2007 to amend its regulations to require newly designed power 
reactors to take into account the potential effects of the impact of a large commercial aircraft. 17 
As discussed in the previous section, NRC considers an aircraft attack to be beyond the design 
basis threat that plants must be able to withstand, so the requirements of the proposed rule were 
intended to provide an additional margin of safety. The proposed rule would affect only new 
reactor designs not previously certified by NRC, because the previous designs were still 
considered adequately safe. Nevertheless, Westinghouse submitted changes in the certified design 
of its AP1000 reactor to NRC on May 29, 2007, proposing to line the inside and outside of the 
reactor’s concrete containment structure with steel plates to increase resistance to aircraft 
penetration.18 
Under NRC’s 2007 proposed rule, applicants for new certified designs or for new reactor licenses 
using uncertified designs would have been required to assess the effects that a large aircraft crash 
would have on the proposed facilities. Each applicant would then describe how the plant’s design 
features, capabilities, and operations would avoid or mitigate the effects of such a crash, 
particularly on core cooling, containment integrity, and spent fuel storage pools. 
In response to comments, the NRC staff proposed in October 2008 that the aircraft impact 
assessments be conducted by all new reactors, including those using previously certified 
designs.19 The NRC Commissioners, in a 3-1 vote, approved the change February 17, 2009, 20 and 
it was published in the Federal Register June 12, 2009.21 The new rule added specific design 
requirements that all new reactors would have to meet: 
Each applicant subject to this section shall perform a design-specific assessment of the 
effects on the facility of the impact of a large, commercial aircraft. Using realistic analyses, 
the applicant shall identify and incorporate into the design those design features and 
functional capabilities to show that, with reduced use of operator actions: 
(A) the reactor core remains cooled, or the containment remains intact; and 
(B) spent fuel cooling or spent fuel pool integrity is maintained. 
As noted above, NRC rejected proposals that existing reactors—in addition to new reactors—be 
required to protect against aircraft crashes, such as by adding “beamhenge” barriers. NRC 
determined that damage from aircraft crashes at existing reactors would be sufficiently mitigated 
                                                             
16 Letter from NRC Chairman Nils J. Diaz to Secretary of Homeland Security Tom Ridge, September 8, 2004. 
17 Federal Register, October 3, 2007 (vol. 72, no. 191), Consideration of Aircraft Impacts for New Nuclear Power 
Reactor Designs. 
18 MacLachlan, Ann, “Westinghouse Changes AP1000 Design to Improve Plane Crash Resistance,” Nucleonics Week, 
June 21, 2007. 
19 Nuclear Regulatory Commission, Final Rule—Consideration of Aircraft Impacts for New Nuclear Power Reactors, 
Rulemaking Issue Affirmation, SECY-08-0152, October 15, 2008. 
20 Nuclear Regulatory Commission, Final Rule—Consideration of Aircraft Impacts for New Nuclear Power Reactors, 
Commission Voting Record, SECY-08-0152, February 17, 2009. 
21 Nuclear Regulatory Commission, Consideration of Aircraft Impacts for New Nuclear Power Reactors, Final Rule, 74 
Federal Register 28111, June 12, 2009. This provision is codified at 10 CFR 50.150. 
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by measures that had already been required by all reactors. In 2002, NRC ordered all nuclear 
power plants to develop strategies to mitigate the effects of large fires and explosions that could 
result from aircraft crashes or other causes.22 As part of a broad security rulemaking effort, NRC 
proposed in October 2006 to incorporate the 2002 order on fire and explosion strategies into its 
security regulations (10 CFR Part 73).23 In response to comments, NRC published a supplemental 
proposed rule in April 2008 to move the fire and explosion requirements into its reactor licensing 
regulations at 10 CFR Part 50, along with requirements that reactors establish procedures for 
responding to specific aircraft threat notifications.24 Those regulations received final approval by 
the NRC Commissioners December 17, 2008,25 and were published in the Federal Register March 
27, 2009.26 A key provision in the new rule states: 
Each licensee shall develop and implement guidance and strategies intended to maintain or 
restore core cooling, containment, and spent fuel pool cooling capabilities under the 
circumstances associated with loss of large areas of the plant due to explosions or fire, to 
include strategies in the following areas: 
(i) Fire fighting; 
(ii) Operations to mitigate fuel damage; and 
(iii) Actions to minimize radiological release.27 
Spent Fuel Storage 
When no longer capable of sustaining a nuclear chain reaction, highly radioactive “spent” nuclear 
fuel is removed from the reactor and stored in a pool of water in the reactor building and at many 
sites later transferred to dry casks on the plant grounds. Because both types of storage are located 
outside the reactor containment structure, particular concern has been raised about the 
vulnerability of spent fuel to attack by aircraft or other means. If terrorists could breach a spent 
fuel pool’s concrete walls and drain the cooling water, the spent fuel’s zirconium cladding could 
overheat and catch fire. 
The National Academy of Sciences (NAS) released a report in April 2005 that found that 
“successful terrorist attacks on spent fuel pools, though difficult, are possible,” and that “if an 
attack leads to a propagating zirconium cladding fire, it could result in the release of large 
amounts of radioactive material.” NAS recommended that the hottest spent fuel be interspersed 
with cooler spent fuel to reduce the likelihood of fire, and that water-spray systems be installed to 
                                                             
22 Nuclear Regulatory Commission, Final Rule—Consideration of Aircraft Impacts for New Nuclear Power Reactors, 
Rulemaking Issue Affirmation, SECY-08-0152, October 15, 2008, p. 2. 
23 Nuclear Regulatory Commission, “Power Reactor Security Requirements, Proposed Rule,” 71 Federal Register 
62664, October 26, 2006. 
24 Nuclear Regulatory Commission, “Power Reactor Security Requirements, Supplemental Proposed Rule,” 73 Federal 
Register 19443, April 10, 2008. 
25 Nuclear Regulatory Commission, “NRC Approves Final Rule Expanding Security Requirements for Nuclear Power 
Plants,” press release, December 17, 2008, http://www.nrc.gov/reading-rm/doc-collections/news/2008/08-227.html. 
26 Nuclear Regulatory Commission, Power Reactor Security Requirements, Final Rule, 74 Federal Register 13925, 
March 27, 2009. 
27 10 CFR 50.54(hh)(2). 
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cool spent fuel if pool water were lost. The report also called for NRC to conduct more analysis 
of the issue and consider earlier movement of spent fuel from pools into dry storage.28 
NRC agreed with some of findings of the NAS study but disagreed in several areas. In a report to 
Congress in response to the NAS report, NRC stated: 
In summary, the NRC believes based on information developed in NRC vulnerability 
assessments, that the Committee has identified some scenarios that are unreasonable. The 
NRC also disagrees with some NAS recommendations and its conclusion lacks a sound 
technical basis. The NAS finding that earlier movement of spent fuel from pools into dry 
storage would be prudent is one such example.29 
NRC conducted the site-specific analyses recommended by NAS with funding provided by the 
FY2006 Energy and Water Development Appropriations Act (P.L. 109-103, H.Rept. 109-275). 
NRC’s March 2009 regulations cited above include “spent fuel pool cooling capabilities” as a 
function that must be addressed by nuclear plants’ mitigation strategies for large fires and 
explosions. Protection of spent fuel cooling also is included in the design requirements for new 
reactors under NRC’s June 2009 aircraft impact regulations. 
NRC has long contended that the potential effects of terrorist attacks are not “reasonably 
foreseeable” impacts that must be included in environmental studies for proposed spent fuel 
storage and other nuclear facilities. However, the U.S. Court of Appeals for the 9th Circuit ruled in 
June 2006 that terrorist attacks must be included in the environmental study of a dry storage 
facility at California’s Diablo Canyon nuclear plant. NRC reissued the Diablo Canyon study May 
29, 2007, to comply with the court ruling, but it did not include terrorism in other recent 
environmental studies outside the jurisdiction of the 9th Circuit.30 The U.S. Court of Appeals for 
the 3rd Circuit subsequently ruled that NRC did not have to consider the impact of terrorist attacks 
in the license renewal application for the Oyster Creek plant in New Jersey.31 
Long-term management of spent nuclear fuel is currently undergoing review, but spent fuel stored 
at reactor sites is expected to be moved eventually to central storage, permanent disposal, or 
reprocessing facilities. (For details, see CRS Report RL33461, Civilian Nuclear Waste Disposal, 
by Mark Holt.) Large-scale transportation campaigns would increase public attention to NRC 
transportation security requirements and related security issues. 
Force-on-Force Exercises 
EPACT05 codified an NRC requirement that each nuclear power plant conduct security exercises 
every three years to test its ability to defend against the design basis threat. In these “force-on-
force” exercises, closely monitored and evaluated by NRC, a mock adversary force from outside 
the plant attempts to penetrate the plant’s vital area and simulate damage to a “target set” of key 
                                                             
28 National Academy of Sciences, Board on Radioactive Waste Management, Safety and Security of Commercial Spent 
Nuclear Fuel Storage, Public Report (online version), released April 6, 2005. 
29 U.S. Nuclear Regulatory Commission Report to Congress on the National Academy of Sciences Study on the Safety 
and Security of Commercial Spent Nuclear Fuel Storage, March 2005, p. iii, http://www.nrc.gov/reading-rm/doc-
collections/congress-docs/correspondence/2005/domenici-03142005.pdf. 
30 Beattie, Jeff, “NRC Takes Two Roads on Terror Review Issue,” Energy Daily, February 27, 2007. 
31 U.S. Court of Appeals for the Third Circuit, New Jersey Department of Environmental Protection v. U.S. Nuclear 
Regulatory Commission, March 31, 2009, http://www.ca3.uscourts.gov/opinarch/072271p.pdf. 
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safety components. Actual damage to such components could result in radioactive releases from 
the plant. Participants in the tightly controlled exercises carry weapons modified to fire only 
blanks and laser bursts to simulate bullets, and they wear laser sensors to indicate hits. Other 
weapons and explosives, as well as destruction or breaching of physical security barriers, may 
also be simulated. While one squad of the plant’s guard force is participating in a force-on-force 
exercise, another squad is also on duty to maintain normal plant security. Plant defenders know 
that a mock attack will take place sometime during a specific period of several hours, but they do 
not know what the attack scenario will be. Multiple attack scenarios are conducted over several 
days of exercises. 
Full implementation of the force-on-force program began in late 2004. Standard procedures and 
other requirements have been developed for using the force-on-force exercises to evaluate plant 
security and as a basis for taking regulatory enforcement action. Many tradeoffs are necessary to 
make the exercises as realistic and consistent as possible without endangering participants or 
regular plant operations and security. 
NRC required the nuclear industry to develop and train, under NRC standards, a “composite 
adversary force” comprising security officers from many plants to simulate terrorist attacks in all 
force-on-force exercises conducted after October 2004. However, in September 2004 testimony, 
GAO criticized the industry’s selection of Wackenhut (now G4S Regulated Security Solutions), a 
security company that guards many U.S. nuclear plants, to manage the adversary force, including 
non-Wackenhut employees. In addition to raising “questions about the force’s independence,” 
GAO noted that Wackenhut had been accused of cheating on previous force-on-force exercises by 
the Department of Energy.32 Exelon terminated its security contracts with Wackenhut in late 2007 
after guards at the Peach Bottom reactor in York County, Pennsylvania, were discovered sleeping 
while on duty.33 
EPACT05 requires NRC to “mitigate any potential conflict of interest that could influence the 
results of a force-on-force exercise, as the Commission determines to be necessary and 
appropriate.” NRC prohibits officers in the adversary force from participating in exercises at their 
home plants. As in previous years, NRC’s 2009 annual security report to Congress found that the 
industry adversary teams “continued to meet expectations for a credible, well-trained, and 
consistent mock adversary force.”34 
Through calendar year 2009, NRC had completed two-thirds of the second three-year cycle of 
force-on-force exercises at the 64 U.S. nuclear plant sites.35 From the start of the program in 2004 
through 2009, 112 force-on-force inspections were conducted, with each inspection typically 
                                                             
32 GAO. “Nuclear Regulatory Commission: Preliminary Observations on Efforts to Improve Security at Nuclear Power 
Plants.” Statement of Jim Wells, Director, Natural Resources and Environment to the Subcommittee on National 
Security, Emerging Threats, and International Relations, House Committee on Government Reform. September 14, 
2004. p. 14. 
33 Washington Post, “Executive Resigns in Storm Over Sleeping Guards,” January 10, 2008. 
34 Nuclear Regulatory Commission, Office of Nuclear Security and Incident Response, Report to Congress on the 
Security Inspection Program for Commercial Power Reactor and Category 1 Fuel Cycle Facilities: Results and Status 
Update; Annual Report for Calendar Year 2009, NUREG-1885, Rev. 3, July 2010, p. 8, http://www.nrc.gov/reading-
rm/doc-collections/nuregs/staff/sr1885/r3/sr1885r3.pdf. 
35 NRC generally lists 65 U.S. plant sites, but the adjacent Hope Creek and Salem sites in New Jersey are considered to 
be a single site for security exercises. E-mail message from David Decker, NRC Office of Congressional Affairs, 
March 13, 2009. 
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including three mock attacks by the adversary force. During the 112 inspections, 8 complete 
target sets were simulated to be damaged or destroyed, indicating inadequate protection against 
the DBT, and additional security measures were promptly implemented, according to NRC. The 
inspections resulted in a total of 49 findings of security deficiencies, 40 of which were of 
relatively low significance. Follow-up force-on-force exercises are sometimes conducted to verify 
that the necessary security improvements have been made.36 
Emergency Response 
After the 1979 accident at the Three Mile Island nuclear plant near Harrisburg, PA, Congress 
required that all nuclear power plants be covered by emergency plans. NRC requires each plant to 
have an Emergency Planning Zone (EPZ) with an approximately 10-mile radius. Within the 
emergency EPZ, the plant operator must maintain warning sirens or other systems and regularly 
conduct emergency response exercises evaluated by NRC and the Federal Emergency 
Management Agency (FEMA). 
In light of the increased possibility of terrorist attacks that, if successful, could result in the 
release of radioactive material, proposals have been made to expand the EPZ to include larger 
population centers. NRC determined that the 10-mile EPZ remained adequate, but it issued a 
bulletin in July 2005 identifying enhancements for emergency response plans in the case of 
“security-based events at a nuclear power plant.”37 
The potential release of radioactive iodine during a nuclear incident is a particular concern, 
because iodine tends to concentrate in the thyroid gland of persons exposed to it. Emergency 
plans in many states include distribution of iodine pills to the population within the EPZ. Taking 
non-radioactive iodine before exposure would prevent absorption of radioactive iodine but would 
afford no protection against other radioactive elements. In 2002, NRC began providing iodine 
pills to states requesting them for populations within the 10-mile EPZ. 
Security Personnel and Other Issues 
After video recordings of inattentive security officers at the Peach Bottom (PA) nuclear power 
plant were aired on local television, an NRC inspection in late September 2007 confirmed that 
there had been multiple occasions on which multiple security officers were inattentive.38 
However, after a follow-up inspection into security issues at the Peach Bottom plant, run by 
Exelon Nuclear, the NRC concluded that the plant’s security program had not been significantly 
degraded as a result of the guards’ inattentiveness. NRC issued a bulletin December 12, 2007, 
requiring all nuclear power plants to provide written descriptions of their “managerial controls to 
deter and address inattentiveness and complicity among licensee security personnel.”39 
                                                             
36NRC Office of Nuclear Security and Incident Response, op. cit. 
37 NRC Office of Nuclear Security and Incident Response, Emergency Preparedness and Response Actions for 
Security-Based Events, NRC Bulletin 2005-02, July 18, 2005, http://www.nrc.gov/reading-rm/doc-collections/gen-
comm/bulletins/2005/bl200502.pdf. 
38 NRC, NRC Commences Follow-up Security Inspection at Peach Bottom, November 5, 2007, http://www.nrc.gov/
reading-rm/doc-collections/news/2007/07-057.i.html. 
39 Nuclear Regulatory Commission, Security Officer Attentiveness, NRC Bulletin 2007-1, Washington, DC, December 
(continued...) 
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Nuclear Power Plant Security and Vulnerabilities 
 
The incident drew harsh criticism from the House Committee on Energy and Commerce. “The 
NRC’s stunning failure to act on credible allegations of sleeping security guards, coupled with its 
unwillingness to protect the whistleblower who uncovered the problem, raises troubling 
questions,” said Representative John D. Dingell, then-Chairman of the Committee.40 NRC 
proposed a $65,000 fine on Exelon Nuclear on January 6, 2009.41 
Following the 9/11 terrorist attacks, NRC conducted a “top-to-bottom” review of its nuclear 
power plant security requirements. On February 25, 2002, the agency issued “interim 
compensatory security measures” to deal with the “generalized high-level threat environment” 
that continued to exist, and on January 7, 2003, it issued regulatory orders that tightened nuclear 
plant access. On April 29, 2003, NRC issued orders to restrict security officer work hours, 
establish new security force training and qualification requirements, and increase the DBT that 
nuclear security forces must be able to defend against, as discussed previously. 
In October 2006, NRC proposed to amend the security regulations and add new security 
requirements that would codify the series of orders issued after 9/11 and respond to requirements 
in the Energy Policy Act of 2005.42 The new security regulations were approved by the NRC 
Commissioners on December 17, 2008, and published March 27, 200943: 
•  Safety and Security Interface. Explicit requirements are established for nuclear 
plants to ensure that necessary security measures do not compromise plant safety. 
•  Mixed-Oxide Fuel. Enhanced physical security requirements are established to 
prevent theft or diversion of plutonium-bearing mixed-oxide (MOX) fuel. 
•  Cyber Security. Nuclear plants must submit security plans that describe how 
digital computer and communications systems and safety-related networks are 
protected from cyber attacks. 
•  Aircraft Attack Mitigative Strategies and Response. As discussed in the earlier 
section on vulnerability to aircraft crashes, nuclear plants must prepare strategies 
for responding to warnings of an aircraft attack and for mitigating the effects of 
large explosions and fires. 
•  Plant Access Authorization. Nuclear plants must implement more rigorous 
programs for authorizing access, including enhanced psychological assessments 
and behavioral observation. 
•  Security Personnel Training and Qualification. Modifications to security 
personnel requirements include additional physical fitness standards, increased 
minimum qualification scores for mandatory personnel tests, and requirements 
for on-the-job training. 
                                                             
(...continued) 
12, 2007. 
40 Committee on Energy and Commerce, Energy and Commerce Committee to Probe Breakdowns in NRC Oversight, 
January 7, 2008 http://energycommerce.house.gov/Press_110/110nr149.shtml. 
41 Nuclear Regulatory Commission, “NRC Proposes $65,000 Fine for Violations Associated with Inattentive Security 
Guards at Peach Bottom Nuclear Plant,” press release, January 6, 2009, http://www.nrc.gov/reading-rm/doc-
collections/news/2009/09-001.i.html. 
42 Federal Register, October 26, 2006 (vol. 71, no. 207), NRC, Power Reactor Security Requirements, Proposed Rule. 
43 Federal Register, March 27, 2009, op. cit. 
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Nuclear Power Plant Security and Vulnerabilities 
 
•  Physical Security Enhancements. New requirements are intended to ensure the 
availability of backup security command centers, uninterruptible power supplies 
to detection systems, enhanced video capability, and protection from waterborne 
vehicles. 
A proposal by NRC staff to release more details about the results of nuclear plant security 
inspections was defeated by the NRC Commissioners in a 2-2 vote on January 21, 2009. Under 
current policy, NRC announces after a security inspection whether any violations that were found 
were of low safety significance or moderate-or-higher safety significance. Critics of the current 
policy contend that the public needs more detail to be assured of plant security. The policy’s 
supporters counter that greater information about security inspection findings could inadvertently 
provide useful information to terrorists.44 
 
 
Author Contact Information 
 
Mark Holt 
  Anthony Andrews 
Specialist in Energy Policy 
Specialist in Energy and Defense Policy 
mholt@crs.loc.gov, 7-1704 
aandrews@crs.loc.gov, 7-6843 
 
 
                                                             
44 Jenny Weil, “Commissioners Reach Stalemate on Security-Related Amendment,” Inside NRC, February 2, 2009. 
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