Dirty bombsUrgent need: Dirty bomb detection technology which does not rely on helium

Published 4 June 2014

It has taken 4.7 billion years for Earth to accumulate our helium reserves, but these reserves are dwindling at an alarming rate, and will be exhausted by around 2025. The supplies we have originated in the very slow radioactive alpha decay that occurs in rocks, and there is no chemical way to manufacture helium. The Department of Defense and other agencies use Helium-3 (He-3) to detect neutrons emanating from Special Nuclear Material (SNM) in order to counter the threat of nuclear-fueled explosives such as dirty bombs. Since the supply of He-3 is rapidly drying up, the Defense Threat Reduction Agency (DTRA) awarded a $2.8 million contract to Alion Science and Technology to develop a replacement technology which will detect neutrons without relying on He-3.

Sophisticated detection methods are required to counter the threat of nuclear-fueled explosives such as dirty bombs. Historically, the Department of Defense and other agencies used Helium-3 (He-3) to detect neutrons emanating from Special Nuclear Material (SNM). The supply of He-3, an extremely rare non-naturally occurring substance, is rapidly drying up (see “The world is running out of helium,” HSNW, 6 October 2010; and “U.S. policy may lead to growing global shortage of helium,” HSNW, 1 May 2013).

To address the need for a means to detect neutrons that does not rely on He-3, the Defense Threat Reduction Agency (DTRA) awarded a $2.8 million contract to Alion Science and Technology to develop enhancements to a replacement technology.

Alion will support DTRA by developing new methods to use an advanced detection system which uses boron-coated “straws” — literally bundles of thin copper tubes with a coating of boron, an abundant element.

Current He-3 detectors are omnidirectional, so they can only alert users to the presence of neutrons. Under the contract, Alion will develop methods to make the boron-coated straw detector directional, so that a search team can pinpoint the location of the source of neutrons and thus react to threats more effectively.

Alion says its engineers also will research how to increase the detector’s efficiency by exploring new straw geometries and will focus on miniaturizing and speeding up the electronics.

Additionally, Alion will review various manufacturing technologies to reduce the technology’s overall production costs.

By researching the means to make the boron-coated straw detector more precise and more reasonable to produce, Alion can help DTRA employ improved technologies to mitigate threats effectively and keep warfighters and citizens safe,” said Terri Spoonhour, Alion Senior Vice President and Distributed Simulation Group Manager. “But, beyond providing a drop-in replacement for He-3 detector components, this engineering effort opens up a number of possibilities for new or enhanced portable systems that can be carried into questionable areas or permanently installed to protect ports and depots.”

Alion’s teaming partner is Proportional Technologies Inc. of Houston. The period of performance runs until 1 March 2017.