Combating nuclear terrorism

Posted: February 7, 2013 - 6:42pm | Y-12 Report | Volume 9, Issue 2 | 2013

Researchers have the unique opportunity to measure uranium in multiple forms and enrichments to test nuclear detection devices.

Y-12's Nuclear Detection and Sensor Testing Center and other site programs are invaluable in blocking the illicit trafficking and use of nuclear materials.

For seven decades, Y-12 has served a primarily defense-oriented mission, providing parts for every nuclear weapon in the U.S. stockpile. Today the site is expanding its mission to support nuclear nonproliferation and global security initiatives aimed at securing nuclear materials, and associated weapon technologies, worldwide. One such endeavor, the commission of the Y-12 Nuclear Detection and Sensor Testing Center, is designed to combat the diversion and illicit trafficking of nuclear materials.

“Diversion is a significant threat as terrorist groups are attempting to acquire sufficient quantities of fissile materials to improvise nuclear weapons — weapons that could be smuggled into our country and used on American soil,” NDSTC Director Carter Hull said. The NDSTC was created to provide researchers with dedicated facilities to test radiation sensors, detector instrumentation and associated systems. The center has two testing venues: Site 1 is for classified applications, and Site 2 provides testing opportunities for university research groups and nuclear instrumentation companies, as well as for colleagues from national laboratories.

NDSTC offers unique testing opportunities — radiation measurements with uranium in a wide variety of forms and uranium-235 enrichments, including highly enriched uranium in specific configurations,” Hull said. “Tests conducted at the center help to improve the systems used for detecting and characterizing nuclear materials, especially fissile materials. These tests contribute to our nation's defense.”

Researchers may propose experiments to determine the capabilities of their detection equipment under various conditions and operational scenarios. After undergoing a rigid review and approval process, user groups may deploy their detection systems at NDSTC and conduct passive or active interrogation measurements. Passive measurements are for detecting natural radiation emissions from uranium. Active interrogation uses an external energy source, such as a neutron generator, to enhance or create a detectable signal from special nuclear materials such as highly enriched uranium.

Readying NDSTC for operation was no simple matter. Program Manager Scott Creasey, who served as the center's first operations manager, had to coordinate numerous safety and technical reviews and integrate the project with ongoing nuclear operations. The Y-12 Plant Directed Research and Development program provided funds for developing the facility.

“Without the significant support and investments provided by the PDRD program, the testing center would not have been possible,” said Hull. “Their assistance has been invaluable.” Personnel from a number of Y-12 organizations have contributed greatly to the center's establishment and successful operations. After nearly two years of planning and preparations, the NDSTC officially welcomed user groups in late 2010. Researchers from various U.S. national laboratories have performed measurements at both sites.

NDSTC Operations Manager Julia Cantrell is completing approvals for active interrogation measurements at Site 2. “Active measurements are important because of the difficulties in detecting passive radiation from shielded highly enriched uranium,” Cantrell said. “It's relatively easy to shield the lower energies of gamma-ray radiation and limited neutrons that highly enriched uranium emits naturally.”

Ultimately, the center reflects the varying ways in which Y-12 serves national security interests. Gerald DeVault, director of Nuclear Nonproliferation and Global Security Programs, recognizes this as an important step for Y-12's nonproliferation work: “The NDSTC is a great example of how Y-12 is applying our people, facilities and materials to solve the nuclear security challenges of the 21st century.”