Non-Proliferation Nuclear Forensics: Canadian Perspective

By Slobodan V. Jovanovic

In this monograph, the authors provide an overview of Canada’s NF capability in addition to general aspects of the nuclear forensics that is useful for both nuclear forensic practitioners and for countries that are signatories to the Nuclear Non-proliferation treaty in establishing their NF capability. The authors summarize challenges that first responders face at crime scenes involving RN materials. Next, they describe the RN materials from the uranium fuel cycle in Canada that are most relevant to NF and a summary of their use and construction, possible NF signatures, and how those signatures were used in the Canadian exercise. Then there is an overview of selected NF laboratory methods, along with an important example of radiochronometric measurements. The importance of Certified Reference Materials specific for NF is described, along with the Canadian perspective. The Laboratory Network chapter provides the Canadian experience in establishing the nuclear forensic capability, while Nuclear Forensic Library chapter describes in general the need and establishment of the NNFL, with some details on the Canadian project. In the final chapter, the authors discuss the Canadian experience in using its nuclear forensic capability in two international exercises.

• Language: English
• Publisher: ASME Press
• Release date: May 1, 2020
• ISBN: 9780791862049

Book preview

1. Introduction

Nuclear forensics (NF) is by no means new. It is as old as the first use of nuclear materials in weapons. For example, in 1944 the U.S. Air Force searched for evidence of radioactive xenon gas (¹³³Xe) in the atmosphere to monitor the German nuclear program [1]. Such monitoring activities are being practiced both internationally through the framework of the Csomprehensive Nuclear-Test-Ban Treaty Organization (CTBTO) [2] and nationally by many countries across the world. For example, in September 2017, South Korea’s radionuclide monitoring system recorded and reported the detection of ¹³³Xe subsequent to nuclear bomb tests allegedly performed by North Korea (see [3]).

NF is an emerging field in the law enforcement community [1, 4, 5, 6, 7, 8]. The discipline is pertinent to a criminal or terrorist activity involving radioactive or nuclear (RN) material. One definition of nuclear forensics, a sub-discipline of forensic science (referred to as forensics), is as follows [9]:

Nuclear forensics is the examination of nuclear or other radioactive material or of evidence that is contaminated with radionuclides, in the context of legal proceedings under international or national law related to nuclear security.

Possession and transfer of RN materials are very strictly controlled in most countries through nuclear security laws and regulations. At first glance it is difficult to imagine how those materials may escape regulatory control and end up in the wrong hands. So why bother?

There are numerous known attempts to smuggle and sell RN materials worldwide, especially from countries where the regulatory control over those materials is not fully established or has deteriorated [8, 10]. Some recent news articles, such as Nuclear smugglers shopped radioactive material to ISIS and other extremists [11] and Rise in Armenians Arrested for Nuclear-Materials Smuggling Is Worrisome [12], are illustrations of the challenges which the international law enforcement community faces in fighting the attempts to acquire RN materials and use them for terrorist or criminal activities.

Furthermore, several known cases of malevolent use of RN material highlight the importance of having the means to perform forensic analysis [7]. Perhaps the most well-known is the Litvinenko poisoning by ²¹⁰Po in the United Kingdom in 2005 [13]. A recent report on the investigation of Yasser Arafat’s sudden demise and death in 2004 [14] explores the possibility of ²¹⁰Po poisoning in that case as well.

There are several lines of defence when it comes to a malicious act involving RN material. The first line of defence is to take preventive measures to deter such activity by enhancing physical control and tracking through national and international accountancy and other legal instruments. The second line of defence is to have a broad and comprehensive radiation detection capability. Radiation detection instruments can be stationary, installed at key locations, for example at points of entry into a country, such as, ports, airports, border crossings and post offices, or deployed in mobile vehicle laboratories as well as aircrafts and helicopters. Lastly, there are response measures following a nuclear security event including consequence management, investigation, and nuclear forensic analysis.

In Canada, the Canada Border Services Agency (CBSA) has installations of radiation detection portals at several border crossings and marine ports to monitor and screen various cargo containers. Furthermore, there are a number of other organizations equipped with mobile nuclear laboratories (MNL), for example the Royal Canadian Mounted Police (RCMP) and Health Canada. The Canadian MNLs have detection systems capable of detecting and locating radioactive sources in large areas, as well as sample collection equipment, such as air samplers, swipe collection kits, water grabbers and soil augers. The detection equipment includes gamma-ray detectors, such as germanium and sodium iodide (NaI) detectors, liquid scintillation counters for detecting alpha- and beta-emitting radionuclides, as well as survey meters to perform in-situ doserate measurements. Recently, the National Research Council of Canada (NRC) and Natural Resources Canada (NRCan) have developed a Compton gamma imager [15] to complement the existing technologies. When deployed as a mobile survey device, the Compton imager makes possible locating a source discretely without drawing unwanted attention or compromising evidence at the crime scene.

NF has been the focus of the International Atomic Energy Agency (IAEA) efforts to strengthen global nuclear security [9, 16-20], aiming both to achieve credible deterrence to criminals and terrorists and support the detection and investigation of illegal activities with RN material.

When an unlawful activity with RN material is uncovered by law enforcement officials, forensic analysis of that material would normally be required to assist with the investigation. Typical questions for the nuclear forensic professionals are: Is the material safe to handle? What is the composition of the material? From which part of the nuclear fuel cycle does it comes? From where does the material originate? Is it possible to connect the material to any suspect or individual? What would be the use of the material in criminal activity? Is there more of that material outside of regulatory control? Those and similar questions may be answered by highly trained professionals working in specially equipped laboratories.

At present there are two excellent books on NF [4, 5]and numerous review articles [6, 21-30].Overall, nuclear forensic science is rapidly evolving due to progress in chemical and physical methods of analysis of RN materials. In addition, the knowledge base for data interpretation continues to expand, followed by the development of various algorithms for data mining and attribution (nuclear forensic libraries). What is missing at present is strict documentation and validation, i.e. standardization of the analytical methodologies to meet the rigorous requirements for the use of science in the courts. The Canadian requirements for expert witness and laboratory results, established by the Department of Justice and discussed on its web site, (see [31]), may be used as an illustration of the expectations. A similar line of thought was put forward by the U.S. National Research Council [1].

A recent article by the American Physical Society and the American Association for the Advancement of Science [25] provides an analysis of the challenges facing the nuclear forensic field and gives recommendations for overcoming those challenges. Among the most important are the following:

Despite rapid progress in analytical techniques and methods, the databases of RN material signatures are not centralized, which makes comparison of the analytical data with known signatures challenging. It is recommended to increase international cooperation and establish the mechanisms for interrogation of multiple national databases to enable rapid attribution of RN on the basis of comparative signatures. Nuclear forensic experts are highly trained individuals in insufficient numbers and often close to retirement age. It is highly desirable to have accelerated training programs for increasing the numbers of practitioners.

The Nuclear Forensics International Technical Working Group (ITWG) (web site [32]), was established in 1995 to foster international collaboration in the field of NF [33]. The ITWG organizes annual meetings (most recently ITWG-24 in Bucharest, Romania, 2019) to facilitate the exchange of scientific and technical information, offer technical seminars, and hold task group workshops (exercises, guidelines, evidence etc.). It has issued numerous Guidelines, which can be found on its web site, aiming to inform legal experts and laboratory managers about state-of-the-art nuclear forensic techniques and methodologies. The ITWG also organizes collaborative materials exercises (CMX) bi-annually to enable the NF community to practice and advance capabilities in the analysis of RN materials and the interpretation of results.

In this monograph we talk about non-proliferation nuclear forensics, a term coined by Hutcheon et al., in 2015 [34]. To quote the original authors,

Non-proliferation nuclear forensics (NNF) supports international efforts to safeguard the nuclear fuel cycle by supplying information necessary to verify declarations, e.g., compliance with the Nuclear Non-proliferation Treaty, as well as attribute illegally transferred materials.

Since Canada is a signatory to the Nuclear Non-proliferation Treaty [35], this definition aligns perfectly with the Canadian approach in establishing a nuclear forensic capability.

In 2013 the Government of Canada officially launched the Canadian National Nuclear Forensics Capability Project [36] led by the Canadian Nuclear Safety Commission (CNSC), Canada’s nuclear regulator. The mandate of the CNSC is, among others, to implement Canada’s international obligations, which include safeguarding nuclear material and ensuring security of radioactive sources in Canada. As reported in 2015 [36], Canada established a network of nuclear forensic laboratories and began building the National Nuclear Forensic Library (NNFL).

In building Canada’s nuclear forensic capability, we have realized that Canada has well-established expertise arising from a mature nuclear industry and associated regulation. In this monograph, we provide the reader with an overview of Canada’s NF capability in addition to general aspects of the nuclear forensics. We believe that this may be useful for both nuclear forensic practitioners and for countries that are signatories to the Nuclear Non-proliferation treaty in establishing their NF capability.

In the second chapter of the monograph, From Crime Scene to the Laboratory, we summarize challenges, which the first responders are facing at the crime scene involving RN materials. In the following chapter, Nuclear Fuel Cycle, we describe the RN materials from the uranium fuel cycle in Canada that are most relevant to NF. These include uranium ore concentrates, uranium fluorides, uranium oxide fuel pellets, and irradiated fuel. Radioactive Sealed Sources, Chapter 4, provides summary of their use and construction, possible NF signatures and how those signatures were used in the Canadian exercise. In the Nuclear Forensic Methods, Chapter 5, we provide an overview of selected NF laboratory methods, along with an important example of radiochronometric measurements. The importance of Certified Reference Materials specific for NF is described in Chapter 6, along with the Canadian perspective. The Laboratory Network chapter (Chapter 7) provides the Canadian experience in establishing the nuclear forensic capability, while Nuclear Forensic Library (Chapter 8) describes in general the need and establishment of the NNFL, with some details on the Canadian project. Finally, in Chapter 9, we discuss the Canadian experience in using its nuclear forensic capability in two international exercises.

2. From Crime Scene to the Laboratory

Following a catastrophic event, such as a dirty bomb explosion, the crime scene may have victims, weapons, parts of the dirty bomb, as well as RN materials in various degrees of dispersion (intact or distributed). The primary task of the first responders and law enforcement officials would be to assess and secure the crime scene and control the evacuation of the wounded. These are extremely complex tasks for which the first responders are extensively trained. Of paramount importance is the safety of the first responders with respect to radiation hazards while tackling the management of a radiological crime scene. Therefore, the responding law-enforcement and paramedic staff require adequate training in the full assessment of a radiological crime scene for RN materials to ensure the risks due to radiation hazards are minimized and the safety of the persons operating within the environment maximized.

The questions asked at this stage are simply: Is radioactive contamination present? How wide spread is it? Which radionuclide (s) are involved?

To answer those questions, first responders must establish control the crime scene (Figure 2.1) and then collect, package and ship samples to the supporting laboratory (Figure 2.2).

In managing the crime scene, the first responders will [16, 37]:

1)confirm that RN material is present