United States Government Accountability Office

GAO Testimony 

Before the Subcommittee on National 

Security, Emerging Threats, and 

International Relations, House Committee 

on Government Reform

NUCLEAR POWER 

Plants Have Upgraded 

Security, but the Nuclear 

Regulatory Commission 

Needs to Improve Its 

Process for Revising the 

Design Basis Threat 

Statement of Jim Wells, Director 

Natural Resources and Environment 

For Release on Delivery

Expected at 2:00 p.m. EDT

Tuesday, April 4, 2006

 

GAO-06-555T 
What GAO Found

United States Government Accountability Office

Why GAO Did This Study

Highlights

Accountability Integrity Reliability

April 4, 2006

NUCLEAR POWER

Plants Have Upgraded Security, but the 

Nuclear Regulatory Commission Needs to 

Improve Its Process for Revising the 

Design Basis Threat 

Highlights of GAO-06-555T, a testimony 

before the Subcommittee on National 

Security, Emerging Threats, and 

International Relations, Committee on 

Government Reform, House of 

Representatives 

The nation’s commercial nuclear 

power plants are potential targets 

for terrorists seeking to cause the 

release of radioactive material. 

The Nuclear Regulatory

Commission (NRC), an

independent agency headed by five

commissioners, regulates and 

oversees security at the plants. In

April 2003, in response to the 

terrorist attacks of September 11, 

2001, NRC revised the design basis 

threat (DBT), which describes the

threat that plants must be prepared

to defend against in terms of the 

number of attackers and their 

training, weapons, and tactics. 

NRC also restructured its program

for testing security at the plants

through force-on-force inspections

(mock terrorist attacks). This 

testimony addresses the following: 

(1) the process NRC used to 

develop the April 2003 DBT for

nuclear power plants, (2) the 

actions nuclear power plants have 

taken to enhance security in

response to the revised DBT, and

(3) NRC’s efforts to strengthen the 

conduct of its force-on-force 

inspections. This testimony is 

based on GAO’s report on security 

at nuclear power plants, issued on

March 14, 2006 (GAO-06-388). 

What GAO Recommends

In its March 2006 report, GAO 

recommended that NRC improve 

its process for making changes to 

the DBT and evaluate and 

implement measures to further 

strengthen its force-on-force 

inspection program. 

NRC revised the DBT for nuclear power plants using a process that was 

generally logical and well-defined. Specifically, trained threat assessment 

staff made recommendations for changes based on an analysis of 

demonstrated terrorist capabilities. The resulting DBT requires plants to 

defend against a larger terrorist threat, including a larger number of 

attackers, a refined and expanded list of weapons, and an increase in the 

maximum size of a vehicle bomb. Key elements of the revised DBT, such as 

the number of attackers, generally correspond to the NRC threat assessment 

staff’s original recommendations, but other important elements do not. For 

example, the NRC staff made changes to some recommendations after 

obtaining feedback from stakeholders, including the nuclear industry, which 

objected to certain proposed changes, such as the inclusion of certain 

weapons. NRC officials said the changes resulted from further analysis of 

intelligence information. Nevertheless, GAO found that the process used to 

obtain stakeholder feedback created the appearance that changes were

made based on what the industry considered reasonable and feasible to 

defend against rather than on what an assessment of the terrorist threat 

called for. 

Nuclear power plants made substantial security improvements in response 

to the September 11, 2001, attacks and the revised DBT, including security 

barriers and detection equipment, new protective strategies, and additional 

security officers. It is too early, however, to conclude that all sites are 

capable of defending against the DBT because, as of March 30, 2006, NRC 

had conducted force-on-force inspections at 27, or less than half, of the 65 

nuclear power plant sites. 

NRC has improved its force-on-force inspections—for example, by 

conducting inspections more frequently at each site. Nevertheless, in 

observing three inspections and discussing the program with NRC, GAO 

noted potential issues in the inspections that warrant NRC’s continued 

attention. For example, a lapse in the protection of information about the 

planned scenario for a mock attack GAO observed may have given the 

plant’s security officers knowledge that allowed them to perform better than 

they otherwise would have. A classified version of GAO’s report provides 

additional details about the DBT and security at nuclear power plants. 

www.gao.gov/cgi-bin/getrpt?GAO-06-555T.

To view the full product, including the scope 

and methodology, click on the link above. 

For more information, contact Jim Wells at 

(202) 512-3841 or wellsj@gao.gov. 
Mr. Chairman and Members of the Subcommittee: 

I am pleased to be here today to discuss our recent work on security of the 

nation’s 103 operating commercial nuclear power plants, located at 65

sites in 31 states. My testimony today is based on our report being released 

today, entitled Nuclear Power Plants: Efforts Made to Upgrade Security, 

but the Nuclear Regulatory Commission’s Design Basis Threat Process 

Should Be Improved (GAO-06-388).1

As you know, nuclear power plants were among the targets considered in

the original plan for the September 11, 2001, terrorist attacks. 

Furthermore, according to the Nuclear Regulatory Commission (NRC), 

which regulates and oversees the safe operation and security of nuclear 

power plants, there continues to be a general credible threat of a terrorist 

attack on the nation’s commercial nuclear power plants, in particular by al

Qaeda and like-minded Islamic terrorist groups. Such an attack could 

cause a release of radioactive material and endanger public health and

safety through exposure to an elevated level of radiation. 

To defend against a potential terrorist attack, NRC issues and enforces 

security-related regulations and orders, and nuclear power plant licensees 

implement security measures to meet NRC requirements. In particular, 

NRC formulates a design basis threat (DBT)—the threat that plants must 

defend against—and tests plants’ ability to defend against the DBT. The 

DBT characterizes the elements of a potential attack, including the 

number of attackers, their training, and the weapons and tactics they are

capable of employing. NRC periodically reviews the potential terrorist 

threat to determine whether to make changes to the DBT. Most recently, 

NRC revised the DBT in April 2003 in response to the September 11 

terrorist attacks. After revising the DBT, NRC required nuclear power 

plant sites to submit new security plans by April 29, 2004, for its review 

and approval and to implement the security described in their new plans 

by October 29, 2004. In November 2004, NRC began using its force-onforce inspection program to test sites’ ability to defend against the revised 

 1

We also prepared a classified version of our report, which includes additional details about

the DBT and security at nuclear power plants that NRC does not release to the public. For 

more information on NRC’s oversight of security at nuclear power plants, see GAO,

Nuclear Regulatory Commission: Preliminary Observations on Efforts to Improve 

Security at Nuclear Power Plants, GAO-04-1064T (Washington, D.C.: Sept. 14, 2004); and

Nuclear Regulatory Commission: Oversight of Security at Commercial Nuclear Power

Plants Needs to Be Strengthened, GAO-03-752 (Washington, D.C.: Sept. 4, 2003). 

Page 1 GAO-06-555T 
DBT. This program employs mock terrorist attacks as the principal means 

to test the sites’ security. 

The DBT does not represent the maximum size and capability of a terrorist 

attack that is possible but, rather, NRC’s assessment of the threat that the 

nuclear power plants must at all times be prepared to defend against “to 

ensure adequate protection of public health and safety.” Furthermore, 

NRC regulations do not require nuclear power plants to protect against 

attacks by an “enemy of the United States,” whether a foreign government

or other person.2

 NRC originally included this provision in its regulations 

in 1967 (prior to issuing the first DBT for nuclear power plants). According 

to NRC officials, the provision was intended to address the possibility that 

Cuba might launch an attack on a nuclear power plant in Florida. In 

revising the DBT in April 2003, NRC did not use this provision to exempt 

plants from defending against terrorist groups such as al Qaeda but, 

rather, stated that a private security force (such as at a nuclear power 

plant) cannot reasonably be expected to defend against all threats—for 

example, airborne attacks. Importantly, NRC works with other federal 

agencies to coordinate an integrated response to a terrorist threat or 

attack on a nuclear power plant. 

Our March 2006 report examined (1) the process NRC used to develop the

April 2003 DBT for nuclear power plants, (2) the actions nuclear power 

plants have taken to enhance security in response to the revised DBT, and 

(3) NRC’s efforts to strengthen the conduct of its force-on-force 

inspections. For the report, we reviewed documents detailing the process 

NRC used to revise the DBT and interviewed the NRC commissioners and 

staff. We also visited four nuclear power plant sites (one in each of the 

four NRC regions) to observe the security enhancements that sites made 

to address the revised DBT, and we reviewed a sample of NRC’s baseline 

and force-on-force inspection reports. GAO staff with security expertise 

accompanied us on our visits in order to assist in our review of the sites’ 

security strategies. Finally, we observed a total of three force-on-force 

inspections at two other sites. We performed our work from November 

2004 through January 2006 in accordance with generally accepted 

government auditing standards. 

 2

0 C.F.R. § 50.13. 

Page 2 GAO-06-555T 
NRC revised the DBT for nuclear power plants using a process that was 

generally logical and well-defined. Specifically, trained threat assessment

staff made recommendations for changes based on an analysis of 

demonstrated terrorist capabilities. To enhance the predictability and 

consistency of its assessments and its recommendations to the NRC 

commissioners for changes to the DBT, the NRC threat assessment staff 

developed and used a comprehensive screening tool to analyze 

intelligence information and to evaluate particular terrorist capabilities, or

“adversary characteristics,” for inclusion in the DBT. The resulting DBT 

requires plants to defend against a larger terrorist threat, including a larger 

number of attackers, a refined and expanded list of weapons, and an 

increase in the maximum size of a vehicle bomb. The revised DBT 

generally, but not always, corresponded to the original recommendations 

of the threat assessment staff. For example, the maximum number of 

attackers in the revised DBT is based, in part, on the staff’s analysis of the 

size of terrorist cells worldwide. However, for other important elements of 

the DBT, such as the weapons that attackers could use against a plant, the 

final version of the revised DBT does not correspond to the staff’s original 

recommendations. We identified the following two principal reasons for 

these differences: 

Summary 

• First, the threat assessment staff made changes to its initial 

recommendations after obtaining feedback from stakeholders, including 

the nuclear industry, on a draft of the DBT. A number of the changes 

reflected industry objections to the draft. For example, following meetings

with industry, the staff decided not to recommend including certain 

weapons in the list of adversary characteristics that nuclear power plants 

should be prepared to defend against. In its comments, the industry had 

pressed for NRC to remove such adversary characteristics from the draft 

DBT. The industry considered them to be prohibitively expensive to 

defend against or to be representative of an enemy of the United States,

which is the responsibility of the government, rather than the industry, to 

defend against. NRC officials told us the changes resulted from further 

analysis of the intelligence data and the reasonableness of required 

defensive measures rather than the industry objections. Nevertheless, in 

our view, this situation created the appearance that changes were made 

based on what industry considered reasonable and feasible to defend 

against, rather than an assessment of the terrorist threat. 

• Second, in deciding on the revised DBT, the commissioners largely 

supported the staff’s recommendations but also made some significant 

changes. These changes reflected their policy judgments on what is 

reasonable for a private security force to defend against. However, the 

commissioners did not identify explicit criteria for what is and what is not 

Page 3 GAO-06-555T 
reasonable for a private security force to defend against, such as the cost

of defending against particular adversary characteristics. For example, the 

commissioners decided against including two weapons that the threat 

assessment staff had concluded could plausibly be used against a U.S. 

nuclear power plant. Furthermore, instead of providing a reason for its 

decision to remove these weapons, the commission’s voting record 

showed that individual commissioners used differing criteria and 

emphasized different factors, such as cost or practicality of defensive 

measures. We believe the absence of reviewable criteria reduced the 

transparency of the decision-making process. The absence of criteria also

potentially reduced the rigor of the decision-making process. 

Licensees of nuclear power plants have made substantial changes to their 

security in response to the September 11, 2001, attacks and the 2003 

revisions to the DBT. At the sites we visited, these actions included, for 

example, adding security barriers and detection equipment, implementing 

new protective strategies, enhancing access control, and hiring additional 

security officers. In some cases, the sites went beyond what NRC required. 

For example, one site added electronic intrusion detection equipment to 

its outer perimeter, which was not required. According to NRC, other sites 

implemented security enhancements similar to what we saw at the sites 

we visited. Despite these considerable efforts, it is too early to conclude

that all sites are capable of defending against the DBT because, as of 

March 30, 2006, NRC had conducted force-on-force inspections at 27, or 

less than half, of the 65 sites. According to NRC, sites have generally 

performed well during force-on-force inspections, and the results of 

baseline inspections show that sites have generally complied with their 

security plans. However, a number of sites have experienced problems 

and have not always met security requirements. Most notably, we 

observed a force-on-force inspection at a site in which the licensee’s 

performance at the time was at best questionable in its ability to defend 

against the DBT. 

NRC has made a number of improvements to its force-on-force inspection 

program. For example, NRC is implementing a schedule to conduct the 

inspections more frequently at each site—every 3 years rather than every 8 

years—and has instituted measures to make the inspections more realistic, 

such as using laser equipment to better simulate the weapons that 

attackers and security officers would likely employ during an actual attack

on a nuclear power plant. These improvements are important because, as 

we noted from our observation of three force-on-force inspections and our 

review of NRC reports on others, the inspections have the ability to detect 

weaknesses in sites’ protective strategies, which can then be corrected. 

Page 4 GAO-06-555T 
Nevertheless, in observing three inspections and discussing the program 

with NRC officials, we noted issues in the force-on-force program that 

warrant continued NRC attention. For example, the level of security 

expertise and training among controllers, who observe exercise 

participants to ensure the safety and effectiveness of the exercises, was 

inconsistent. 

Our report included two recommendations to address the shortcomings in 

the process NRC used to revise the DBT. First, we recommended that NRC 

assign responsibility for obtaining feedback from the nuclear industry and 

other stakeholders on proposed changes to the DBT to an office within 

NRC other than the threat assessment section, thereby insulating the staff 

and mitigating the appearance of undue industry influence on the threat 

assessment itself. Second, we recommended that NRC develop explicit 

criteria to guide the commissioners in their deliberations to approve 

changes to the DBT. These criteria should include setting out the specific 

factors and how they will be weighed in deciding what is reasonable for a 

private guard force to defend against. In addition, we recommended that

NRC continue to evaluate and implement measures to further strengthen 

the force-on-force inspection program. In commenting on a draft of our 

report, NRC commended our efforts to ensure that the report was accurate

and constructive. NRC also provided additional clarifying comments 

pertaining to the process it used to revise the DBT for nuclear power 

plants. For example, NRC requested that we revise the report to explain 

that it made a deliberate decision to develop the revised DBT while 

simultaneously seeking input from stakeholders in order to expedite its 

response to the September 11, 2001 terrorist attacks. We revised the report 

accordingly.

NRC is an independent agency established by the Energy Reorganization 

Act of 1974 to regulate the civilian use of nuclear materials. It is headed by

a five-member commission, with one commission member designated by 

the President to serve as chairman and official spokesperson. The 

commission as a whole formulates policies and regulations governing 

nuclear reactor and materials safety and security, issues orders to 

licensees, and adjudicates legal matters brought before it. Security for 

commercial nuclear power plants is addressed by NRC’s Office of Nuclear

Security and Incident Response. This office develops policy on security at

nuclear facilities and is the agency’s security interface with the 

Department of Homeland Security (DHS), the intelligence and law 

enforcement communities, the Department of Energy (DOE), and other 

agencies. Within this office, the Threat Assessment Section assesses 

Background 

Page 5 GAO-06-555T 
security threats involving NRC-licensed activities and develops 

recommendations regarding the DBT for the commission’s consideration. 

The DBT for radiological sabotage applied to nuclear power plants 

identifies the terrorist capabilities (or “adversary characteristics”) that 

sites are required to defend against. The adversary characteristics 

generally describe the components of a ground assault and include the 

number of attackers; the size of a vehicle bomb; and the weapons, 

equipment, and tactics that could be used in an attack. Other threats in the 

DBT include a waterborne assault and the threat of an insider. The DBT 

does not include the threat of an airborne attack.

Force-on-force inspections are NRC’s performance-based means for 

testing the effectiveness of nuclear power plant security programs. These 

inspections are intended to demonstrate how well a nuclear power plant 

might defend against a real-life threat. In a force-on-force inspection, a 

professional team of adversaries attempts to reach specific “target sets” 

within a nuclear power plant that would allow them to commit 

radiological sabotage. These target sets represent the minimum pieces of 

equipment or infrastructure an attacker would need to destroy or disable 

in order to commit radiological sabotage that results in an elevated release 

of radioactive material to the environment. NRC also conducts baseline 

inspections at nuclear power plants. During these inspections, security 

inspectors examine areas such as officer training, fitness for duty, 

positioning and operational readiness of multiple physical and technical 

security components, and the controls the licensee has in place to ensure 

that unauthorized personnel do not gain access to the protected area.

NRC’s policy is to conduct a baseline inspection at each site every year, 

with the complete range of baseline inspection activities conducted over a 

3-year cycle. For both force-on-force and baseline inspections, licensees 

are responsible for immediately correcting or compensating for any 

deficiency in which NRC concludes that security is not in accordance with 

the approved security plans or other security orders. 

Page 6 GAO-06-555T 
The process by which NRC revised the DBT for nuclear power plants was 

generally logical and well defined in that trained threat assessment staff 

made recommendations for changes based on an analysis of demonstrated 

terrorist capabilities. The NRC commissioners evaluated the 

recommendations and considered whether the proposed changes 

constituted characteristics representative of an enemy of the United 

States, or were otherwise not reasonable for a private security force to 

defend against. However, while the final version of the revised DBT 

generally corresponded to the original recommendations of the threat 

assessment staff, some elements did not, which raised questions about the 

extent to which the revised DBT represents the terrorist threat. 

NRC made its 2003 revisions to the DBT for nuclear power plants using a 

process that the agency has had in place since issuing the first DBT in the 

late 1970s. In this process, NRC staff trained in threat assessment use 

reports and secure databases provided by the intelligence community to 

monitor information on terrorist activities worldwide. (NRC does not 

directly gather intelligence information but rather receives intelligence 

from other agencies that it uses to formulate the DBT for nuclear power 

plants.) The staff analyze this information both to identify specific 

references to nuclear power plants and to determine what capabilities 

terrorists have acquired and how they might use those capabilities to 

attack nuclear power plants in the United States. The staff normally 

summarize applicable intelligence information and any recommendations 

for changes to the DBT in semiannual reports to the NRC commissioners 

on the threat environment. 

In 1999, the NRC staff began developing a set of criteria—the adversary 

characteristics screening process—to decide whether to recommend 

particular adversary characteristics for inclusion in the DBT and to 

enhance the predictability and consistency of their recommendations. The 

staff use initial screening criteria to exclude from further consideration 

certain adversary characteristics, such as those that would more likely be

used by a foreign military than by a terrorist group. For adversary 

characteristics that pass the initial round of screening, the threat 

assessment staff apply additional screening factors, such as the type of 

terrorist group that demonstrated the characteristic. For example, the staff 

consider whether an adversary characteristic has been demonstrated by 

transnational or terrorist groups operating in the United States, or by 

terrorist groups that operate only in foreign countries. Finally, on the basis

of their analysis and interaction with intelligence and other agencies, the

staff decide whether to recommend that the commission include the 

NRC’s Process for 

Revising the DBT Was 

Generally Logical and 

Well Defined, but 

Some Changes Were 

Not Clearly Linked to 

an Analysis of the 

Terrorist Threat 

NRC’s Process for Revising 

Its DBT Was Generally 

Logical and Well Defined 

Page 7 GAO-06-555T 
adversary characteristics in the DBT for nuclear power plants. NRC’s 

Office of Nuclear Security and Incident Response, which includes the 

Threat Assessment Section, reviews and endorses the threat assessment 

staff’s analysis and recommendations. 

Terrorist attacks have generally occurred outside the United States, and 

intelligence information specific to nuclear power plants is very limited. 

As a result, one of the NRC threat assessment staff’s major challenges has 

been to decide how to apply this limited information to nuclear power 

plants in the United States. For example, one of the key elements in the 

revised DBT, the number of attackers, is based on NRC’s analysis of the 

group size of previous terrorist attacks worldwide. According to NRC 

threat assessment staff, the number of attackers in the revised DBT falls 

within the range of most known terrorist cells worldwide.3

 NRC staff 

recommendations regarding other adversary characteristics also reflected 

the staff’s interpretation of intelligence information. For example, the staff 

considered a range of sizes for increasing the vehicle bomb in the revised 

DBT and ultimately recommended a size that was based on an analysis of

previous terrorist attacks using vehicle bombs. Intelligence and law 

enforcement officials we spoke with did not have information 

contradicting NRC’s interpretation regarding the number of attackers or 

other parts of the NRC DBT but did point to the uncertainty regarding the 

size of potential attacks and the relative lack of intelligence on the 

terrorist threat to nuclear power plants. 

In addition to analyzing intelligence information, NRC monitored and 

exchanged information with DOE, which also has a DBT for comparable

facilities that process or store radiological materials and are, therefore, 

potential targets for radiological sabotage.4

 However, while certain aspects

of the two agencies’ DBTs for radiological sabotage are similar, NRC 

generally established less rigorous requirements than DOE— for example, 

with regard to the types of equipment that could be used in an attack. The 

DOE DBT includes a number of weapons not included in the NRC DBT. 

Inclusion of such weapons in the NRC DBT for nuclear power plants 

 3

In this report, “terrorist cell” refers only to terrorists who participate in an attack, not

those who support but do not participate in an attack.

4

For further information on the DOE DBT, see GAO, Nuclear Security: DOE’s Office of the 

Under Secretary for Energy, Science and Environment Needs to Take Prompt, 

Coordinated Action to Meet the New Design Basis Threat, GAO-05-611 (Washington, D.C.: 

July 15, 2005); and Nuclear Security: DOE Needs to Resolve Significant Issues before It

Fully Meets the New Design Basis Threat, GAO-04-623 (Washington, D.C.: Apr. 27, 2004).

Page 8 GAO-06-555T 
would have required plants to take substantial additional security 

measures. Furthermore, DOE included other capabilities in its DBT that 

are not included in the NRC DBT. Despite these differences, both agencies

used similar intelligence information to derive key aspects of their DBTs. 

For example, both DOE and NRC based the number of attackers on 

intelligence on the size of terrorist cells, and DOE officials told us they 

used intelligence similar to NRC’s to derive the number of attackers. 

Likewise, DOE and NRC officials provided us with similar analyses of 

intelligence information on previous terrorist attacks using vehicle bombs. 

DOE and NRC officials also told us that most vehicle bombs used in 

terrorist attacks are smaller than the size of the vehicle bomb in NRC’s 

revised DBT. 

While NRC followed a generally logical and well-defined process to revise 

the DBT for nuclear power plants, two aspects of the process raised a 

fundamental question—the extent to which the DBT represents the 

terrorist threat as indicated by intelligence data compared with the extent 

to which it represents the threat that NRC considers reasonable for the 

plants to defend against. These two aspects were (1) the process NRC 

used to obtain stakeholder feedback on a draft of the DBT and (2) changes 

made by the commissioners to the NRC staff’s recommended DBT. 

With regard to the first aspect, the process NRC used to obtain feedback 

from stakeholders, including the nuclear industry, created the appearance 

of industry influence on the threat assessment regarding the 

characteristics of an attack. NRC staff sent a draft DBT to stakeholders in 

January 2003, held a series of meetings with them to obtain their 

comments, and received written comments. NRC specifically sought and 

received feedback from the nuclear industry on what is reasonable for a 

private security force to defend against and the cost of and time frame for 

implementing security measures to defend against specific adversary 

characteristics. During this same period, the threat assessment staff 

continued to analyze intelligence information and modify the draft DBT. 

In its written comments on the January 2003 draft DBT, the Nuclear 

Energy Institute (NEI), which represents the nuclear power industry, 

objected to a number of the adversary characteristics the NRC staff had 

included. Subsequently, the NRC staff made changes to the draft DBT, 

Changes to the Threat 

Assessment Staff’s Initial 

Recommendations Were 

Not Clearly Linked to an 

Analysis of the Terrorist 

Threat 

Page 9 GAO-06-555T 
which they then submitted to the NRC commissioners.5

 The changes made

by the NRC staff—in particular, the size of the vehicle bomb and list of 

weapons that could be used in an attack—reflected some (but not all) of 

NEI’s objections. For example, NEI wrote that some sites would not be 

able to protect against the size of the vehicle bomb proposed by NRC 

because of insufficient land for installation of vehicle barrier systems at a 

necessary distance. Instead, NEI agreed that it would be reasonable to 

protect against a smaller vehicle bomb. Similarly, NEI argued against the 

inclusion of certain weapons because of the cost of protecting against the 

weapons. NEI wrote that such weapons (as well as the vehicle bomb size 

initially proposed by the NRC staff) would be indicative of an enemy of the 

United States, which sites are not required to protect against under NRC 

regulations. In its final recommendations to the commissioners, the NRC 

staff reduced the size of the vehicle bomb to the amount NEI had 

proposed and removed a number of weapons NEI had objected to. On the 

other hand, NRC did not make changes that reflected all of the industry’s 

objections. For example, NRC staff did not remove one particular weapon

NEI had objected to, which, according to NRC’s analysis, has been a staple

in the terrorist arsenal since the 1970s and has been used extensively 

worldwide. 

With regard to the commissioners’ review and approval of the NRC staff’s 

recommendations, the commissioners largely supported the staff’s 

recommendations but also made some significant changes that reflected

policy judgments. Specifically, the commissioners considered whether any 

of the recommended changes to the DBT constituted characteristics 

representative of an enemy of the United States, which sites are not 

required to protect against under NRC regulations. In approving the 

revised DBT, the commission stated that nuclear power plants’ civilian 

security forces cannot reasonably be expected to defend against all 

threats, and that defense against certain threats (such as an airborne 

attack) is the primary responsibility of the federal government, in 

coordination with state and local law enforcement officials. Based on such 

considerations, the commission voted to remove two weapons the NRC 

staff had recommended for inclusion in the revised DBT based on its 

threat assessment. However, the document summarizing the commission’s 

decision to approve the revised DBT did not provide a reason for 

excluding these weapons. For example, the commission did not indicate 

 5

The NRC staff submitted their final draft DBT to the commissioners for their review and 

approval in April 2003, together with a summary of stakeholder comments. 

Page 10 GAO-06-555T 
whether its decision was based on criteria, such as the cost for nuclear 

power plants to defend against an adversary characteristic or the efforts of 

local, state, and federal agencies to address particular threats. In our view, 

the lack of such criteria reduced the transparency of the commission’s 

decisions to make changes to the threat assessment staff’s 

recommendations. 

The four nuclear power plant sites we visited made substantial changes in

response to the revised DBT, including measures to detect, delay, and 

respond to the increased number of attackers and to address the increased

vehicle bomb size. These security enhancements were in addition to other

measures licensees implemented—such as stricter requirements for 

obtaining physical access to nuclear power plants—in response to a series

of security orders NRC issued after September 11, 2001. According to NEI, 

as of June 2004, the cost of security enhancements made since September

11, 2001, for all sites amounts to over $1.2 billion.

To enhance their detection capabilities, the four sites we visited installed 

additional cameras throughout different areas of the sites and instituted 

random patrols in the owner-controlled areas.6

 Furthermore, the sites we 

visited installed a variety of devices designed to delay attackers and allow 

security officers more time to respond to their posts and fire upon 

attackers. The sites generally installed these delay devices throughout the 

protected areas as well as inside the reactor and other buildings. Sites also

enhanced their ability to respond to an attack by constructing bulletresistant structures at various locations in the protected area or within 

buildings, increasing the minimum number of security officers defending 

the sites at all times, and expanding the amount of training provided to 

them. (See fig. 1 for an example of a bullet-resistant structure.) According 

to NRC, other sites took comparable actions to defend against the revised

DBT. 

Nuclear Power Plants 

Made Substantial 

Changes to Their 

Security to Address 

the Revised DBT, but 

NRC Inspections 

Have Uncovered 

Problems 

 6

The owner-controlled area refers to the land and buildings within the site boundary that

the owner can limit or allow access to for any reason. The protected area is within the 

owner-controlled area and requires a higher level of access control. The vital area contains 

the sites’ vital equipment, the destruction of which could directly or indirectly endanger 

public health and safety through exposure to radiation. 

Page 11 GAO-06-555T 
Figure 1: Example of a Bullet-Resistant Structure 

In addition to adding measures designed to detect, delay, and respond to 

an attack, the licensees at the four sites we visited installed new vehicle

barrier systems to defend against the larger vehicle bomb in the revised 

DBT. In particular, the licensees designed comprehensive systems that 

included sturdy barriers to (1) prevent a potential vehicle bomb from 

approaching the sites and (2) channel vehicles to entrances where security

officers could search them for explosives and other prohibited items. The 

vehicle barrier systems either completely encircled the plants (except for 

entrances manned by armed security officers) or formed a continuous 

barrier in combination with natural or manmade terrain features, such as 

bodies of water or trenches, that would prevent a vehicle from 

approaching the sites. 

In general, the four sites we visited all implemented a “defense-in-depth” 

strategy, with multiple layers of security systems that attackers would 

have to defeat before reaching vital areas or equipment and destroying or 

disabling systems sufficient to cause an elevated release of radiation off 

Page 12 GAO-06-555T 
site. The sites varied in how they implemented these measures, primarily 

depending on site-specific characteristics such as topography and on the 

degree to which they planned to interdict attackers within the ownercontrolled area and far from the sites’ vital area, as opposed to inside the 

protected area but before they could reach the vital equipment. For 

example, one site with a predominantly external strategy installed an

intrusion detection system in the owner-controlled area so that security 

officers would be able to identify intruders as early as possible. The site 

was able to install such a system because of the large amount of open, 

unobstructed space in the owner-controlled area. In contrast, security 

managers at another site we visited described a protective strategy that 

combined elements of an external strategy and an internal strategy. For 

example, the site identified “choke points”—locations attackers would 

need to pass before reaching their targets—inside the protected area and 

installed bullet-resistant structures at the choke points where officers 

would be waiting to interdict the attackers. NRC officials told us that 

licensees have the freedom to design their protective strategies to 

accommodate site-specific conditions, so long as the strategies satisfy 

NRC requirements and prove successful in a force-on-force inspection. 

In addition to the security enhancements we observed, security managers

at each site described ways in which they had exceeded NRC requirements 

and changes they plan to make as they continue to improve their 

protective strategies. For example, security managers at three of the sites 

we visited told us the number of security officers on duty at any one shift 

exceeded the minimum number of security officers that NRC requires be 

dedicated to responding to attacks. Similarly, in at least some areas of the 

sites, the new vehicle barrier systems were farther from the reactors and 

other vital equipment than necessary to protect the sites against the size of 

vehicle bomb in the revised DBT. 

Despite the substantial security improvements we observed at the four 

sites we visited, it is too early to conclude, either from NRC’s force-onforce or baseline inspections, that all nuclear power plant sites are capable 

of defending against the revised DBT for the following two reasons: 

• First, as of March 30, 2006, NRC had completed force-on-force inspections

at 27 of the 65 sites, and it is not planning to complete force-on-force 

inspections at all sites until 2007, in accordance with its 3-year schedule. 

NRC officials told us that plants have generally performed well during 

force-on-force inspections. However, we observed a force-on-force 

inspection at one site in which the site’s ability to defend against the DBT 

was at best questionable. The site’s security measures appeared 

Page 13 GAO-06-555T 
impressive and were similar to those we observed at other sites. 

Nevertheless, some or all of the attackers were able to enter the protected

area in each of the three exercise scenarios. Furthermore, attackers made

it to the targets in two of the scenarios, although the outcomes of the two 

scenarios were called into question by uncertainties regarding whether the 

attackers had actually been neutralized before reaching the targets. As a 

result, NRC decided to conduct another force-on-force inspection at the 

site, which we also observed. The site made substantial additional security 

improvements—at a cost of $37 million, according to the licensee—and 

NRC concluded after the second force-on-force inspection that the site 

had adequately defended against a DBT-style attack. 

• Second, we noted from our review of 18 baseline inspection reports and 9 

force-on-force inspection reports that sites have encountered a range of 

problems in meeting NRC’s security requirements. NRC officials told us 

that all sites have implemented all of the security measures described in

their new plans submitted in response to the revised DBT. However, 12 of 

the 18 baseline inspection reports and 4 of the 9 force-on-force inspection 

reports we reviewed identified problems or items needing correction. For 

example, during two different baseline inspections, NRC found (1) an 

intrusion detection system in which multiple alarms were not functioning 

properly, making the entire intrusion detection system inoperable, 

according to the site, and (2) three examples of failure to properly search 

personnel entering the protected area, which NRC concluded could reduce 

the overall effectiveness of the protective strategy by allowing the 

uncontrolled introduction of weapons or explosives into the protected 

area. According to NRC, the licensees at these two sites, as well as at the 

other sites where NRC inspection reports noted other problems, took 

immediate corrective actions. 

NRC has made a number of improvements to the force-on-force inspection 

program, several of which address recommendations we made in our 

September 2003 report on NRC’s oversight of security at commercial 

nuclear power plants. We had made our recommendations when NRC was 

restructuring the force-on-force program to provide a more rigorous test 

of security at the sites in accordance with the DBT, which was also under 

revision. For example, we recommended that NRC conduct the 

inspections more frequently at each site, use laser equipment to better 

simulate attackers’ and security officers’ weapons, and require the 

inspections to make use of the full terrorist capabilities stated in the DBT. 

Actions NRC has taken that satisfy these recommendations include 

conducting the exercises more frequently at each site (every 3 years rather 

than every 8 years), and NRC so far is on track to complete the first round 

NRC Has Significantly 

Improved the Forceon-Force Inspection 

Program, but 

Challenges Remain 

Page 14 GAO-06-555T 
of force-on-force inspections on schedule, by 2007. Furthermore, NRC is 

using laser equipment to simulate weapons, and the attackers in the forceon-force exercise inspections that we observed used key adversary 

characteristics of the revised DBT, including the number of attackers, a 

vehicle bomb, a passive insider, and explosives. 

Nevertheless, we identified issues in the force-on-force inspection 

program that could affect the quality of the inspections and that continue 

to warrant NRC’s attention. For example, the level of security expertise 

and training among controllers—individuals provided by the licensee who

observe each security officer and attacker to ensure the safety and 

effectiveness of the exercise—varied in the force-on-force inspections we 

observed. One site used personnel with security backgrounds while 

another site used plant employees who did not have security-related 

backgrounds but who volunteered to help. In its force-on-force inspection 

report for this latter site, NRC concluded that the level of controller 

training contributed to the uncertain outcome of the force-on-force 

exercises, which resulted in NRC’s conducting a second force-on-force 

inspection at the site. 

Furthermore, we noted that the force-on-force exercises end when a site’s

security force successfully stops an attack. Consequently, at sites that 

successfully defeat the mock adversary force early in the exercise 

scenario, NRC does not have an opportunity to observe the performance 

of sites’ internal security—that is, the strategies sites would use to defeat 

attackers inside the vital area. When we raised this issue, NRC officials 

appeared to recognize the benefit of designing the force-on-force 

inspections to test sites’ internal security strategies but said that doing so

would require further consideration of how to implement changes to the 

force-on-force inspections. Based on our observations of three force-onforce inspections, other areas where NRC may be able to make further 

improvements included the following: 

• ensuring the proper use of laser equipment; 

• varying the timing of inspection activities, such as the starting times of the 

mock attacks, in order to minimize the artificiality of the inspections; 

• ensuring the protection of information about the planned scenarios for the 

mock attacks so that security officers do not obtain knowledge that would 

allow them to perform better than they otherwise would; and 

Page 15 GAO-06-555T 
• providing complete feedback to licensees on NRC inspectors’ observations 

on the results of the force-on-force exercises. 

Mr. Chairman, this completes my prepared statement. I would be happy to

respond to any questions you or the other Members of the Subcommittee 

may have at this time. 

For further information about this testimony, please contact me at (202) 

512-3841 (or at wellsj@gao.gov). Raymond H. Smith, Jr. (Assistant 

Director), Joseph H. Cook, Carol Herrnstadt Shulman, and Michelle K. 

Treistman made key contributions to this testimony. 

GAO Contact and 

Staff 

Acknowledgments 

Page 16 GAO-06-555T (360681) 
This is a work of the U.S. government and is not subject to copyright protection in the 

United States. It may be reproduced and distributed in its entirety without further 

permission from GAO. However, because this work may contain copyrighted images or 

other material, permission from the copyright holder may be necessary if you wish to 

reproduce this material separately. 
GAO’s Mission The Government Accountability Office, the audit, evaluation and 

investigative arm of Congress, exists to support Congress in meeting its 

constitutional responsibilities and to help improve the performance and 

accountability of the federal government for the American people. GAO 

examines the use of public funds; evaluates federal programs and policies; 

and provides analyses, recommendations, and other assistance to help

Congress make informed oversight, policy, and funding decisions. GAO’s 

commitment to good government is reflected in its core values of 

accountability, integrity, and reliability. 

The fastest and easiest way to obtain copies of GAO documents at no cost

is through GAO’s Web site (www.gao.gov). Each weekday, GAO posts 

newly released reports, testimony, and correspondence on its Web site. To

have GAO e-mail you a list of newly posted products every afternoon, go 

to www.gao.gov and select “Subscribe to Updates.” 

The first copy of each printed report is free. Additional copies are $2 each. 

A check or money order should be made out to the Superintendent of 

Documents. GAO also accepts VISA and Mastercard. Orders for 100 or 

more copies mailed to a single address are discounted 25 percent. Orders 

should be sent to: 

U.S. Government Accountability Office 

441 G Street NW, Room LM 

Washington, D.C. 20548 

To order by Phone: Voice: (202) 512-6000 

TDD: (202) 512-2537 

Fax: (202) 512-6061 

Contact: 

Web site: www.gao.gov/fraudnet/fraudnet.htm

E-mail: fraudnet@gao.gov

Automated answering system: (800) 424-5454 or (202) 512-7470 

Gloria Jarmon, Managing Director, JarmonG@gao.gov (202) 512-4400 

U.S. Government Accountability Office, 441 G Street NW, Room 7125 

Washington, D.C. 20548 

Paul Anderson, Managing Director, AndersonP1@gao.gov (202) 512-4800

U.S. Government Accountability Office, 441 G Street NW, Room 7149 

Washington, D.C. 20548 

Obtaining Copies of 

GAO Reports and 

Testimony

Order by Mail or Phone 

To Report Fraud,

Waste, and Abuse in 

Federal Programs 

Congressional 

Relations 

Public Affairs 

PRINTED ON RECYCLED PAPER