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  4. Written testimony of DNDO for a House Homeland Security Subcommittee on Infrastructure Protection, and Security Technologies hearing titled “Preventing Nuclear Terrorism: Does DHS have an Effective and Efficient Nuclear Detection Strategy”

Written testimony of Domestic Nuclear Detection Office Acting Director Dr. Huban Gowadia for a House Committee on Homeland Security, Subcommittee on Infrastructure Protection, and Security Technologies hearing titled “Preventing Nuclear Terrorism: Does DHS have an Effective and Efficient Nuclear Detection Strategy”

Release Date: July 26, 2012

311 Cannon House Office Building

Good morning Chairman Lungren, Ranking Member Clarke, and distinguished Members of the Subcommittee. As Acting Director of the Department of Homeland Security’s (DHS) Domestic Nuclear Detection Office (DNDO), I am pleased to testify today with my distinguished colleagues to discuss nuclear detection. My testimony today will focus on the DNDO’s progress in coordinating the global nuclear detection architecture (GNDA) and implementing the domestic portion.

DNDO is a unique interagency organization, with staff expertise in technical, law enforcement, military, and interagency issues, focused exclusively on preventing nuclear terrorism. Countering nuclear terrorism is a whole-of-government challenge, and DNDO works with Federal, state, local, tribal, territorial, international, and private sector partners to fulfill this mission. Working in coordination with partners from across the U.S. government (USG), including DHS components, the Departments of Energy (DOE), State, Defense (DOD), Justice, the Intelligence Community, and the Nuclear Regulatory Commission, DNDO develops the global nuclear detection architecture (GNDA) and implements the domestic component of the architecture. DNDO also works with its partners to coordinate interagency efforts to develop technical nuclear detection capabilities, measure detector system performance, ensure effective response to detection alarms, integrate USG nuclear forensics efforts, and conduct transformational research and development for advanced detection and forensics technologies.

DNDO continues to build upon the concept of an interagency GNDA. We are working with partners to build a flexible, multi-layered, architecture that will strategically integrate Federal, state, local, territorial, and tribal assets and capabilities into a unified response when intelligence or information indicates there may be a credible nuclear threat. The USG must be able to respond effectively to credible information that indicates an imminent threat to our national security, and, if necessary, surge all available resources in a coordinated manner. Since a surge relies on detection resources that are in place at the time, this places a premium on identifying what is needed to respond to threats and ensuring it will be available if needed. The USG strategy leverages the integrated efforts of Federal, state, local, territorial, and tribal responders to perform nuclear detection in concentrated regions or areas when information indicates there may be a need for responsive search operations for preventive detection or interdiction. DNDO continues to develop new equipment and technology that is flexible and mobile, enhancing the ability of the USG to respond to radiological and nuclear threats.

DHS GNDA Implementation Plan

Building upon the interagency GNDA Strategic Plan, which we submitted to Congress in December of 2010, DNDO led the Department’s development of the DHS GNDA Implementation Plan. This plan represents the next step in the development of the Department’s operational and coordinated capability to respond to radiological and nuclear threats against the homeland. The planning team was made up of representatives from across DHS operational components and headquarters offices, as well as interagency representatives.

The DHS GNDA Implementation Plan identifies specific DHS-led programs and activities that will support the mission, goals, and responsibilities detailed in the GNDA Strategic Plan.

As requested by Congress, the plan also includes current resource planning information based on the Future Years Homeland Security Program.

The GNDA will require constant review to account for changing threats, missions, and technology. Through this implementation planning process, DHS has developed metrics associated with GNDA Strategic Plan performance goals. These metrics define achievement and timelines for each performance goal.

Maintaining and Enhancing Capabilities at Ports of Entry

Over the past decade, DHS has made considerable progress in deploying systems at our borders and seaports to scan cargo and vehicles for radiological and nuclear threats. Through the Radiation Portal Monitor (RPM) program, detection equipment is procured and installed at domestic ports of entry to scan containerized cargo for radiological and nuclear threats, addressing the requirements of the Security and Accountability For Every (SAFE) Port Act of 2006 (Pub. L. No. 109-347). Our ongoing work with U.S. Customs and Border Protection (CBP) to facilitate container security has resulted in the scanning of over 99 percent of all incoming containerized cargo for radiological and nuclear threats entering via truck at our land borders and at our seaports, utilizing RPMs. RPMs, coupled with handheld radioisotope identification devices (RIIDs), are the workhorses of our on-going deployments.

Scanning of containerized cargo at seaports of entry will continue, in accordance with SAFE Port Act requirements. However, given the current fiscal environment, DNDO and CBP, working together, will continue to work to balance risk reduction, effectiveness of radiological and nuclear scanning, flow and volume of commerce, and life cycle costs when determining RPM deployment priorities.

Improvements to Current Generation RPMs
We are looking ahead in anticipation of a future need for enhanced capabilities or new systems for scanning cargo at ports of entry. The RPM program began deployment of the current generation poly-vinyl toluene (PVT) RPMs in 2003 and many of these are approaching the 10 year service life mark. While recent DNDO-funded studies have shown that the service life of PVT RPMs may be significantly longer than was previously anticipated, the oldest RPMs will eventually need to be replaced or refurbished. Given the very significant DHS investment in the RPM program, DNDO has been studying the issue of how to extend the usefulness of this investment and develop the system to its full potential. DNDO’s PVT Improvement Program examines technical methods to improve the operations and capabilities of currently deployed PVT RPMs. DNDO plans to complete developmental testing and field validation testing of selected PVT improvement solutions in FY 2013.

Next Generation Handheld Detectors
Radioisotope Identification Devices (RIIDs) are used by law enforcement officers and technical experts during routine operations. To further improve operational nuclear detection capability, DNDO has led the development of a next-generation RIID. We worked closely with CBP, USCG, the TSA, and state and local operators, to identify key operational requirements that drove the design of the new system. Based on an enhanced detection material, lanthanum bromide, and improved algorithms, this new handheld technology is easy-to-use, lightweight, and more reliable, and because it has built in calibration and diagnostics, has a much lower annual maintenance cost. We are currently in the process of deploying these with CBP at POEs.

Advanced Spectroscopic Portals (ASP)
Last year, my predecessor announced the Department’s decision to cancel full-scale deployment of the ASP system for either primary or secondary scanning. At the recommendation of the Department’s Acquisition Review Board, Secretary Napolitano directed DNDO and CBP to end the ASP program as originally conceived and to instead use hardware left over from the ASP program to collect spectroscopic data from operational environments that can be used to characterize future models and refine operational requirements. Based upon a careful review of needs and resources, DNDO is working with CBP, as well as state authorities, to determine locations for data collection purposes. The data gathered will be used for modeling and to refine requirements, especially in the areas of detecting special nuclear materials in the presence of masking, and for characterizing the effect of conveyance speed control on isotope identification.

DNDO Acquisition and Commercial Engagement Strategy

Recognizing the important contributions and innovations of private industry, national laboratories, and academia, DNDO has evolved its acquisition focus from one that is predominantly fueled by a government-funded, government-managed development process to one that relies upon industry-led development. As such, all DNDO technology development programs now proceed with a “commercial first” approach – engaging first with the private sector for solutions and only moving to a government-sponsored and managed development effort if necessary. This approach takes advantage of industry’s innate flexibility and ability to rapidly improve technologies, leveraging industry-led innovation.

This transition will also include a new approach at the systems level, in which strategic interfaces will be clearly defined in the detector/system architecture, allowing system upgrades without wholesale changes. We have shared the DNDO Acquisition and Commercial Engagement Strategy with industry through DHS’s Private Sector Office to ensure the commercial sector remains aligned with DNDO’s current development and acquisition approach. In some cases, shifting to commercial-based acquisitions will reduce the total time to test, acquire, and field technology.

Research and Development to Support and Enhance the Architecture

Along with intelligence and law enforcement, technology is fundamental in our ability to detect nuclear threats. In recent years, there have been dramatic advancements in nuclear detection technology. Thirty years ago, identification of detected nuclear material required laboratory specialists and large, complicated equipment. Now, newer detection materials that can be integrated into mobile and human-portable devices, coupled with advanced algorithms, allow for significantly improved operations. As a result, frontline responders and law enforcement officials now regularly use detection equipment to search for, find, and identify nuclear materials in the field. Technological advances in computing, communications, software, and hardware have also contributed to this revolution in nuclear detection technology.

Despite these advancements, however, developing nuclear detection technology for homeland security applications is an inherently difficult technical task. The fundamental technical challenge for nuclear detection is one of distinguishing signal from noise. Sensors can detect radiation, but detection is limited by several factors, including speed, distance, shielding, and source strength. Compounding these challenges is the difficulty in distinguishing ever-present background radiation from radiation that poses a threat. Additionally, to mitigate risk across all pathways in the GNDA, detection technologies must be capable of operations in challenging environments, such as on the water and in rugged terrain between ports of entry.

While DNDO’s work to develop, evaluate, and deploy systems supports the ongoing enhancement of the GNDA, significant technical challenges remain. These challenges include:

  • Cost effective equipment with sufficient technical performance to ensure widespread deployment;
  • Enhanced wide area search capabilities in a variety of scenarios to include urban and highly cluttered environments;
  • Monitoring along challenging GNDA pathways, to include scanning of general aviation and small maritime vessels, and searching for nuclear threats between ports of entry; and
  • Detection of nuclear threats even when heavily shielded.

Additionally, our programs must be able to reach out to operators for user requirements and to balance both “technology push” and “technology pull” efforts, as appropriate. For the former, the technology developer is pushing a new concept out for examination by the operator. These systems may be otherwise unknown to operators, and are often state-of-the-art with enhanced or improved threat detection capabilities and may further allow for simplified operational use. Technology pull refers to equipment and programs where operators have identified new concepts of operation and/or features that they need in order to achieve their missions. The operators are constantly pulling the technologies in directions that guide our development of detection systems.

DNDO works to address these challenges through a robust, long term, multi-faceted transformational and applied research and development (R&D) program. I would like to highlight a few of the projects in our transformational R&D portfolio that are showing significant progress and promise.

Helium-3 Alternatives
Helium-3 has been widely used as a neutron detection component for radiation detection devices, such as RPMs. However, in recent years, our country has faced a helium-3 shortage. Years before the recent helium-3 shortage, DNDO was already exploring options for better, more cost-effective, alternatives for neutron detection. DNDO’s transformational and applied research efforts included fourteen different technologies that could be used instead of helium-3 tubes, including those based on boron or lithium.

Once the shortage was identified, DNDO accelerated this progress and led an interagency working group to address the use of alternate neutron detection technologies. DNDO also queried the commercial marketplace for available systems. At a recently-completed test, present and next generation alternatives from DNDO’s research and development and the private sector were evaluated and multiple systems proved to have sufficient performance to replace helium-3 in RPMs. As a result of DNDO’s efforts, alternative neutron detection technologies are now commercially available and large quantities of helium-3 will no longer be necessary for use in RPMs. Importantly, due to a collaborative, USG-wide effort to address the shortfall, our U.S. strategic reserve of helium-3 has increased by 40 percent since 2009.

Advanced Radiation Monitoring Device (ARMD)
Our Advanced Radiation Monitoring Device (ARMD) project focuses on enhancing our ability to distinguish benign radiological and nuclear materials, from those that potentially pose a threat. The ARMD project capitalizes on the efficiency and energy resolution of emerging detector crystals, such as strontium iodide (SrI2) and cesium lithium yttrium chloride, or “CLYC”, to develop smaller, more capable detection systems. Through DNDO’s efforts, the detector materials have sufficiently matured to the point where they are now commercially available. New handheld detector systems using these crystals are being designed, built, and will soon be ready for formal evaluation by DNDO.

Long Range Radiation Detection (LRRD) Project
Our Long Range Radiation Detection (LRRD) project has the potential to have broad operational impact by significantly improving the range of detectors. Through the LRRD project, DNDO has been developing advanced technologies to detect, identify, and precisely locate radiation sources at stand-off distances, through passive gamma-ray imaging technology. We have focused on two systems: Stand-Off Radiation Detection Systems, which uses a mobile system to locate stationary sources; and the Road Side Tracker, which is a rapidly re-locatable monitoring system capable of identifying and tracking threats in moving vehicles across multiple lanes of traffic. Recent LRRD demonstrations included interagency partners from the technical and law enforcement communities, utilizing a “technology push” to allow operators to use the prototype systems in simulated and operational environments. DNDO is assessing the potential for further development based upon operator feedback and evaluations obtained during the demonstrations.

Networked Detectors
To address nuclear detection in challenging operational environments, DNDO is working on networked detectors. These detectors, being developed in the Intelligent Radiation Sensor System (IRSS) project, are intended to facilitate situational awareness and improve capabilities to detect, identify, locate, and track threats across distributed sensors. The IRSS integrates data from across multiple portable detectors with the goal of improving overall system performance compared to a non-networked system. This technology will support operations where scanning for nuclear threats by routing traffic through checkpoints is not tenable. These operations are conducted at some special security events, between ports of entry along the land border, and include scanning general aviation or small maritime vessels for illicit radiological or nuclear materials.

Detecting Shielded Nuclear Threats
Nuclear threats may be shielded or masked, increasing the challenge for passive detection techniques. To address shielded nuclear threats, DNDO has several important projects. The Shielded Nuclear Alarm Resolution project seeks to develop and characterize advanced active interrogation systems with improved ability to uniquely detect special nuclear material and to resolve alarms with confidence, even in the presence of significant countermeasures (such as shielding). This technology may substantially reduce the number of manual inspections required to resolve alarms, while increasing the probability of nuclear threat detection even when heavily shielded. Technologies of interest include induced fission, high energy backscatter, and nuclear resonance fluorescence.

Recent advancements in the commercial sector have also resulted in technologies that combine the merits of passive and active technologies into a single system through either muon tomography or by integrating radiation detectors into x-ray radiography systems. In theory, these systems should be able to automatically detect nuclear threats, regardless of the shielding level, while providing an image for detecting other anomalies. In order to characterize the full performance capability of these technologies, DNDO recently solicited proposals for our Nuclear and Radiological Imaging Platform Advanced Technology Demonstration. This project will characterize imaging systems for scanning conveyances and identifying possible shielded threats. Results from this demonstration will be available in 2014.

Testing, Evaluation, and Standards for Nuclear Detection Technologies

Over the years, DNDO’s test program has grown and matured. To date, DNDO has conducted more than 70 test and evaluation campaigns at over 20 experimental and operational venues. These test campaigns were planned and executed with interagency partners using rigorous, reproducible, peer-reviewed processes. Tested nuclear detection systems include pagers, handhelds, portals, backpacks, and vehicle-, boat- and spreader bar-mounted detectors, as well as next-generation radiography technologies. The results from DNDO’s test campaigns have informed federal, state, local and tribal operational users on the technical and operational performance of nuclear detection systems, allowing them to select the most suitable equipment and implement effective concepts of operations to detect nuclear threats.

DNDO has also supported the development, publication and adoption of national consensus standards for radiation detection equipment. Several such standards now exist for use in homeland security. DNDO collaborated with the National Institute of Standards and Technology to conduct a review of all national and international consensus standards for nuclear detection systems, and formed an interagency working group to draft government-unique technical capability standards (TCS). Earlier this year, we finalized the first TCS for handheld systems.

The success of the nuclear detection mission is contingent on timely information exchanges. To this end, DNDO successfully collaborated with the National Institute of Standards and Technology to create a major update of the Data Format Standard for Radiation Detectors used for Homeland Security. This standard facilitates the exchange of detection information by ensuring that the systems create and distribute data in a specified format to enable interoperability. Through the International Electrotechnical Commission (IEC) and the American National Standard Institute, this significantly improved standard (IEC 62755) is now internationally accepted. IEC 62755 was approved in late February 2012.

The DNDO Graduated Radiological/Nuclear Detector Evaluation and Reporting (GRaDERSM) Program builds upon these standards to determine if commercially-available nuclear detection equipment complies with established standards. DNDO created the infrastructure for voluntary, vendor testing of commercial nuclear detection technologies by independent, accredited laboratories against national consensus standards and government-unique TCS. This program encourages vendors to develop better nuclear detection and identification systems that meet evolving Homeland Security requirements.

With the maturation of our test and evaluation program, DNDO’s collaboration with interagency partners, such as DOE and DOD, and international partners, such as the United Kingdom, Canada, Israel, the European Union, and the International Atomic Energy Agency (IAEA)), has increased significantly. For example, our close partnership with the DOE Second Line of Defense program, European Commission, and the IAEA for the Illicit Trafficking Radiation Assessment Program+10 (ITRAP+10) will result in a comprehensive evaluation of the performance of nearly one hundred commercially-available radiation detection systems against national and international standards. ITRAP+10 will allow for the refinement of nuclear detection standards and promote greater homogeneity in US and international detection standards. The test program will conclude in the spring of 2013.

Increased Collaboration with Federal, State, and Local Partners

Our ability to counter the nuclear threat is fundamentally based on the critical triad of intelligence, law enforcement and technology. To maximize our ability to detect and interdict nuclear threats, it is imperative that we apply detection technologies in operations that are driven by intelligence indicators and place them in the hands of well-trained law enforcement and public safety personnel.

We have increased our collaboration with the intelligence community. By sharing information, personnel, and requirements, we continue to improve our ability to successfully bring technologies to bear on the nuclear detection mission. Additionally, we have made significant progress in ensuring that law enforcement officers are appropriately trained and equipped for the nuclear detection mission.

DNDO has facilitated the delivery of radiation and nuclear detection training to thousands of Federal, state, and local officers and first responders nationwide. Our work with DHS partners has developed cross-sector capabilities for radiation and nuclear detection: All U.S. Coast Guard (USCG) boarding teams and Transportation Security Administration (TSA) Visible Intermodal Prevention and Response teams are equipped with detection capabilities.

DNDO has also made considerable progress in deploying detection equipment. For example, DNDO has made available radiological and nuclear detection training to over 23,000 state and local law enforcement officers and first responders. In the New York City region, the Securing the Cities (STC) program has funded the deployment of nearly 8,500 pieces of detection equipment and provided the requisite training to over 13,000 personnel. This year, DNDO will also select a second region to implement a phased STC program, tailored to build a regional nuclear detection architecture and integrate state and local capabilities into the Federal response framework. DNDO will assist regional partners in implementing self-supported sustainment of capabilities and sharing of data from fixed, mobile, maritime and human-portable radiation detection systems.

DNDO also supports five Mobile Detection Deployment Units that are operated by our state and local law enforcement partners to provide enhanced detection capability at large public gatherings and special events. With regular use, these units, which are available upon request, are being integrated into exercises, operations, and planning for nuclear search operations in response to threats.


DNDO has come a long way since its creation in 2005. With our integrated approach to GNDA planning, testing and assessments, research and development, acquisition, and operational support, we continue to strengthen the nation’s capabilities to detect and interdict nuclear threats. We appreciate your continued support as we work with our partners to develop, evaluate, deploy, and support the necessary systems to implement a nuclear detection architecture that can effectively respond to credible intelligence and threat information.

Chairman Lungren, Ranking Member Clarke, I thank you for this opportunity to discuss the nuclear detection architecture and the progress of DNDO. I am happy to answer any questions the Subcommittee may have.

Last Updated: 03/10/2022
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